kernel-fxtec-pro1x/drivers/acpi/scan.c

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/*
* scan.c - support for transforming the ACPI namespace into individual objects
*/
#include <linux/module.h>
#include <linux/init.h>
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 02:04:11 -06:00
#include <linux/slab.h>
#include <linux/kernel.h>
#include <linux/acpi.h>
#include <linux/signal.h>
#include <linux/kthread.h>
#include <linux/dmi.h>
ACPI: Add new sysfs interface to export device description Add support to export the device description obtained from the ACPI _STR method, if one exists for a device, to user-space via a sysfs interface. This new interface provides a standard and platform neutral way for users to obtain the description text stored in the ACPI _STR method. If no _STR method exists for the device, no sysfs 'description' file will be created. The 'description' file will be located in the /sys/devices/ directory using the device's path. /sys/device/<bus>/<bridge path>/<device path>.../firmware_node/description Example: /sys/devices/pci0000:00/0000:00.07.0/0000:0e:00.0/firmware_node/description It can also be located using the ACPI device path, for example: /sys/devices/LNXSYSTM:00/device:00/ACPI0004:00/PNP0A08:00/device:13/device:15/description /sys/devices/LNXSYSTM:00/device:00/ACPI0004:00/ACPI0004:01/ACPI0007:02/description Execute the 'cat' command on the 'description' file to obtain the description string for that device. This patch also includes documentation describing how the new sysfs interface works Changes from v1-v2 based on comments by Len Brown and Fengguang Wu * Removed output "No Description" and leaving a NULL attribute if the _STR method failed to evaluate. * In acpi_device_remove_files() removed the redundent check of dev->pnp.str_obj before calling free. This check triggered a message from smatch. Signed-off-by: Lance Ortiz <lance.ortiz@hp.com> Signed-off-by: Len Brown <len.brown@intel.com>
2012-10-02 12:43:23 -06:00
#include <linux/nls.h>
#include <asm/pgtable.h>
#include "internal.h"
#define _COMPONENT ACPI_BUS_COMPONENT
ACPI_MODULE_NAME("scan");
extern struct acpi_device *acpi_root;
#define ACPI_BUS_CLASS "system_bus"
#define ACPI_BUS_HID "LNXSYBUS"
#define ACPI_BUS_DEVICE_NAME "System Bus"
#define ACPI_IS_ROOT_DEVICE(device) (!(device)->parent)
#define INVALID_ACPI_HANDLE ((acpi_handle)empty_zero_page)
/*
* If set, devices will be hot-removed even if they cannot be put offline
* gracefully (from the kernel's standpoint).
*/
bool acpi_force_hot_remove;
static const char *dummy_hid = "device";
static LIST_HEAD(acpi_bus_id_list);
static DEFINE_MUTEX(acpi_scan_lock);
static LIST_HEAD(acpi_scan_handlers_list);
DEFINE_MUTEX(acpi_device_lock);
LIST_HEAD(acpi_wakeup_device_list);
static DEFINE_MUTEX(acpi_hp_context_lock);
struct acpi_device_bus_id{
char bus_id[15];
unsigned int instance_no;
struct list_head node;
};
ACPI / hotplug: Fix concurrency issues and memory leaks This changeset is aimed at fixing a few different but related problems in the ACPI hotplug infrastructure. First of all, since notify handlers may be run in parallel with acpi_bus_scan(), acpi_bus_trim() and acpi_bus_hot_remove_device() and some of them are installed for ACPI handles that have no struct acpi_device objects attached (i.e. before those objects are created), those notify handlers have to take acpi_scan_lock to prevent races from taking place (e.g. a struct acpi_device is found to be present for the given ACPI handle, but right after that it is removed by acpi_bus_trim() running in parallel to the given notify handler). Moreover, since some of them call acpi_bus_scan() and acpi_bus_trim(), this leads to the conclusion that acpi_scan_lock should be acquired by the callers of these two funtions rather by these functions themselves. For these reasons, make all notify handlers that can handle device addition and eject events take acpi_scan_lock and remove the acpi_scan_lock locking from acpi_bus_scan() and acpi_bus_trim(). Accordingly, update all of their users to make sure that they are always called under acpi_scan_lock. Furthermore, since eject operations are carried out asynchronously with respect to the notify events that trigger them, with the help of acpi_bus_hot_remove_device(), even if notify handlers take the ACPI scan lock, it still is possible that, for example, acpi_bus_trim() will run between acpi_bus_hot_remove_device() and the notify handler that scheduled its execution and that acpi_bus_trim() will remove the device node passed to acpi_bus_hot_remove_device() for ejection. In that case, the struct acpi_device object obtained by acpi_bus_hot_remove_device() will be invalid and not-so-funny things will ensue. To protect agaist that, make the users of acpi_bus_hot_remove_device() run get_device() on ACPI device node objects that are about to be passed to it and make acpi_bus_hot_remove_device() run put_device() on them and check if their ACPI handles are not NULL (make acpi_device_unregister() clear the device nodes' ACPI handles for that check to work). Finally, observe that acpi_os_hotplug_execute() actually can fail, in which case its caller ought to free memory allocated for the context object to prevent leaks from happening. It also needs to run put_device() on the device node that it ran get_device() on previously in that case. Modify the code accordingly. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Yinghai Lu <yinghai@kernel.org>
2013-02-13 06:36:47 -07:00
void acpi_scan_lock_acquire(void)
{
mutex_lock(&acpi_scan_lock);
}
EXPORT_SYMBOL_GPL(acpi_scan_lock_acquire);
void acpi_scan_lock_release(void)
{
mutex_unlock(&acpi_scan_lock);
}
EXPORT_SYMBOL_GPL(acpi_scan_lock_release);
void acpi_lock_hp_context(void)
{
mutex_lock(&acpi_hp_context_lock);
}
void acpi_unlock_hp_context(void)
{
mutex_unlock(&acpi_hp_context_lock);
}
void acpi_initialize_hp_context(struct acpi_device *adev,
struct acpi_hotplug_context *hp,
int (*notify)(struct acpi_device *, u32),
void (*uevent)(struct acpi_device *, u32))
{
acpi_lock_hp_context();
hp->notify = notify;
hp->uevent = uevent;
acpi_set_hp_context(adev, hp);
acpi_unlock_hp_context();
}
EXPORT_SYMBOL_GPL(acpi_initialize_hp_context);
int acpi_scan_add_handler(struct acpi_scan_handler *handler)
{
if (!handler)
return -EINVAL;
list_add_tail(&handler->list_node, &acpi_scan_handlers_list);
return 0;
}
int acpi_scan_add_handler_with_hotplug(struct acpi_scan_handler *handler,
const char *hotplug_profile_name)
{
int error;
error = acpi_scan_add_handler(handler);
if (error)
return error;
acpi_sysfs_add_hotplug_profile(&handler->hotplug, hotplug_profile_name);
return 0;
}
/*
* Creates hid/cid(s) string needed for modalias and uevent
* e.g. on a device with hid:IBM0001 and cid:ACPI0001 you get:
* char *modalias: "acpi:IBM0001:ACPI0001"
* Return: 0: no _HID and no _CID
* -EINVAL: output error
* -ENOMEM: output is truncated
*/
static int create_modalias(struct acpi_device *acpi_dev, char *modalias,
int size)
{
int len;
int count;
struct acpi_hardware_id *id;
if (list_empty(&acpi_dev->pnp.ids))
return 0;
len = snprintf(modalias, size, "acpi:");
size -= len;
list_for_each_entry(id, &acpi_dev->pnp.ids, list) {
count = snprintf(&modalias[len], size, "%s:", id->id);
if (count < 0)
return -EINVAL;
if (count >= size)
return -ENOMEM;
len += count;
size -= count;
}
modalias[len] = '\0';
return len;
}
ACPI: Use ACPI companion to match only the first physical device Commit 6ab3430129e2 ("mfd: Add ACPI support") made the MFD subdevices share the parent MFD ACPI companion if no _HID/_CID is specified for the subdevice in mfd_cell description. However, since all the subdevices share the ACPI companion, the match and modalias generation logic started to use the ACPI companion as well resulting this: # cat /sys/bus/platform/devices/HID-SENSOR-200041.6.auto/modalias acpi:INT33D1:PNP0C50: instead of the expected one # cat /sys/bus/platform/devices/HID-SENSOR-200041.6.auto/modalias platform:HID-SENSOR-200041 In other words the subdevice modalias is overwritten by the one taken from ACPI companion. This causes udev not to load the driver anymore. It is useful to be able to share the ACPI companion so that MFD subdevices (and possibly other devices as well) can access the ACPI resources even if they do not have ACPI representation in the namespace themselves. An example where this is used is Minnowboard LPC driver that creates GPIO as a subdevice among other things. Without the ACPI companion gpiolib is not able to lookup the corresponding GPIO controller from ACPI GpioIo resource. To fix this, restrict the match and modalias logic to be limited to the first (primary) physical device associated with the given ACPI comapnion. The secondary devices will still be able to access the ACPI companion, but they will be matched in a different way. Fixes: 6ab3430129e2 (mfd: Add ACPI support) Reported-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-10-24 08:40:54 -06:00
/*
* acpi_companion_match() - Can we match via ACPI companion device
* @dev: Device in question
*
* Check if the given device has an ACPI companion and if that companion has
* a valid list of PNP IDs, and if the device is the first (primary) physical
* device associated with it.
*
* If multiple physical devices are attached to a single ACPI companion, we need
* to be careful. The usage scenario for this kind of relationship is that all
* of the physical devices in question use resources provided by the ACPI
* companion. A typical case is an MFD device where all the sub-devices share
* the parent's ACPI companion. In such cases we can only allow the primary
* (first) physical device to be matched with the help of the companion's PNP
* IDs.
*
* Additional physical devices sharing the ACPI companion can still use
* resources available from it but they will be matched normally using functions
* provided by their bus types (and analogously for their modalias).
*/
static bool acpi_companion_match(const struct device *dev)
{
struct acpi_device *adev;
bool ret;
adev = ACPI_COMPANION(dev);
if (!adev)
return false;
if (list_empty(&adev->pnp.ids))
return false;
mutex_lock(&adev->physical_node_lock);
if (list_empty(&adev->physical_node_list)) {
ret = false;
} else {
const struct acpi_device_physical_node *node;
node = list_first_entry(&adev->physical_node_list,
struct acpi_device_physical_node, node);
ret = node->dev == dev;
}
mutex_unlock(&adev->physical_node_lock);
return ret;
}
ACPI: add module autoloading support for ACPI enumerated devices An ACPI enumerated device may have its compatible id strings. To support the compatible ACPI ids (acpi_device->pnp.ids), we introduced acpi_driver_match_device() to match the driver->acpi_match_table and acpi_device->pnp.ids. For those drivers, MODULE_DEVICE_TABLE(acpi, xxx) is used to exports the driver module alias in the format of "acpi:device_compatible_ids". But in the mean time, the current code does not export the ACPI compatible strings as part of the module_alias for the ACPI enumerated devices, which will break the module autoloading. Take the following piece of code for example, static const struct acpi_device_id xxx_acpi_match[] = { { "INTABCD", 0 }, { } }; MODULE_DEVICE_TABLE(acpi, xxx_acpi_match); If this piece of code is used in a platform driver for an ACPI enumerated platform device, the platform driver module_alias is "acpi:INTABCD", but the uevent attribute of its platform device node is "platform:INTABCD:00" (PREFIX:platform_device->name). If this piece of code is used in an i2c driver for an ACPI enumerated i2c device, the i2c driver module_alias is "acpi:INTABCD", but the uevent of its i2c device node is "i2c:INTABCD:00" (PREFIX:i2c_client->name). If this piece of code is used in an spi driver for an ACPI enumerated spi device, the spi driver module_alias is "acpi:INTABCD", but the uevent of its spi device node is "spi:INTABCD" (PREFIX:spi_device->modalias). The reason why the module autoloading is not broken for now is that the uevent file of the ACPI device node is "acpi:INTABCD". Thus it is the ACPI device node creation that loads the platform/i2c/spi driver. So this is a problem that will affect us the day when the ACPI bus is removed from device model. This patch introduces two new APIs, one for exporting ACPI ids in uevent MODALIAS field, and another for exporting ACPI ids in device' modalias sysfs attribute. For any bus that supports ACPI enumerated devices, it needs to invoke these two functions for their uevent and modalias attribute. Signed-off-by: Zhang Rui <rui.zhang@intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-01-14 01:46:36 -07:00
/*
* Creates uevent modalias field for ACPI enumerated devices.
* Because the other buses does not support ACPI HIDs & CIDs.
* e.g. for a device with hid:IBM0001 and cid:ACPI0001 you get:
* "acpi:IBM0001:ACPI0001"
*/
int acpi_device_uevent_modalias(struct device *dev, struct kobj_uevent_env *env)
{
int len;
ACPI: Use ACPI companion to match only the first physical device Commit 6ab3430129e2 ("mfd: Add ACPI support") made the MFD subdevices share the parent MFD ACPI companion if no _HID/_CID is specified for the subdevice in mfd_cell description. However, since all the subdevices share the ACPI companion, the match and modalias generation logic started to use the ACPI companion as well resulting this: # cat /sys/bus/platform/devices/HID-SENSOR-200041.6.auto/modalias acpi:INT33D1:PNP0C50: instead of the expected one # cat /sys/bus/platform/devices/HID-SENSOR-200041.6.auto/modalias platform:HID-SENSOR-200041 In other words the subdevice modalias is overwritten by the one taken from ACPI companion. This causes udev not to load the driver anymore. It is useful to be able to share the ACPI companion so that MFD subdevices (and possibly other devices as well) can access the ACPI resources even if they do not have ACPI representation in the namespace themselves. An example where this is used is Minnowboard LPC driver that creates GPIO as a subdevice among other things. Without the ACPI companion gpiolib is not able to lookup the corresponding GPIO controller from ACPI GpioIo resource. To fix this, restrict the match and modalias logic to be limited to the first (primary) physical device associated with the given ACPI comapnion. The secondary devices will still be able to access the ACPI companion, but they will be matched in a different way. Fixes: 6ab3430129e2 (mfd: Add ACPI support) Reported-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-10-24 08:40:54 -06:00
if (!acpi_companion_match(dev))
ACPI: add module autoloading support for ACPI enumerated devices An ACPI enumerated device may have its compatible id strings. To support the compatible ACPI ids (acpi_device->pnp.ids), we introduced acpi_driver_match_device() to match the driver->acpi_match_table and acpi_device->pnp.ids. For those drivers, MODULE_DEVICE_TABLE(acpi, xxx) is used to exports the driver module alias in the format of "acpi:device_compatible_ids". But in the mean time, the current code does not export the ACPI compatible strings as part of the module_alias for the ACPI enumerated devices, which will break the module autoloading. Take the following piece of code for example, static const struct acpi_device_id xxx_acpi_match[] = { { "INTABCD", 0 }, { } }; MODULE_DEVICE_TABLE(acpi, xxx_acpi_match); If this piece of code is used in a platform driver for an ACPI enumerated platform device, the platform driver module_alias is "acpi:INTABCD", but the uevent attribute of its platform device node is "platform:INTABCD:00" (PREFIX:platform_device->name). If this piece of code is used in an i2c driver for an ACPI enumerated i2c device, the i2c driver module_alias is "acpi:INTABCD", but the uevent of its i2c device node is "i2c:INTABCD:00" (PREFIX:i2c_client->name). If this piece of code is used in an spi driver for an ACPI enumerated spi device, the spi driver module_alias is "acpi:INTABCD", but the uevent of its spi device node is "spi:INTABCD" (PREFIX:spi_device->modalias). The reason why the module autoloading is not broken for now is that the uevent file of the ACPI device node is "acpi:INTABCD". Thus it is the ACPI device node creation that loads the platform/i2c/spi driver. So this is a problem that will affect us the day when the ACPI bus is removed from device model. This patch introduces two new APIs, one for exporting ACPI ids in uevent MODALIAS field, and another for exporting ACPI ids in device' modalias sysfs attribute. For any bus that supports ACPI enumerated devices, it needs to invoke these two functions for their uevent and modalias attribute. Signed-off-by: Zhang Rui <rui.zhang@intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-01-14 01:46:36 -07:00
return -ENODEV;
if (add_uevent_var(env, "MODALIAS="))
return -ENOMEM;
ACPI: Use ACPI companion to match only the first physical device Commit 6ab3430129e2 ("mfd: Add ACPI support") made the MFD subdevices share the parent MFD ACPI companion if no _HID/_CID is specified for the subdevice in mfd_cell description. However, since all the subdevices share the ACPI companion, the match and modalias generation logic started to use the ACPI companion as well resulting this: # cat /sys/bus/platform/devices/HID-SENSOR-200041.6.auto/modalias acpi:INT33D1:PNP0C50: instead of the expected one # cat /sys/bus/platform/devices/HID-SENSOR-200041.6.auto/modalias platform:HID-SENSOR-200041 In other words the subdevice modalias is overwritten by the one taken from ACPI companion. This causes udev not to load the driver anymore. It is useful to be able to share the ACPI companion so that MFD subdevices (and possibly other devices as well) can access the ACPI resources even if they do not have ACPI representation in the namespace themselves. An example where this is used is Minnowboard LPC driver that creates GPIO as a subdevice among other things. Without the ACPI companion gpiolib is not able to lookup the corresponding GPIO controller from ACPI GpioIo resource. To fix this, restrict the match and modalias logic to be limited to the first (primary) physical device associated with the given ACPI comapnion. The secondary devices will still be able to access the ACPI companion, but they will be matched in a different way. Fixes: 6ab3430129e2 (mfd: Add ACPI support) Reported-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-10-24 08:40:54 -06:00
len = create_modalias(ACPI_COMPANION(dev), &env->buf[env->buflen - 1],
ACPI: add module autoloading support for ACPI enumerated devices An ACPI enumerated device may have its compatible id strings. To support the compatible ACPI ids (acpi_device->pnp.ids), we introduced acpi_driver_match_device() to match the driver->acpi_match_table and acpi_device->pnp.ids. For those drivers, MODULE_DEVICE_TABLE(acpi, xxx) is used to exports the driver module alias in the format of "acpi:device_compatible_ids". But in the mean time, the current code does not export the ACPI compatible strings as part of the module_alias for the ACPI enumerated devices, which will break the module autoloading. Take the following piece of code for example, static const struct acpi_device_id xxx_acpi_match[] = { { "INTABCD", 0 }, { } }; MODULE_DEVICE_TABLE(acpi, xxx_acpi_match); If this piece of code is used in a platform driver for an ACPI enumerated platform device, the platform driver module_alias is "acpi:INTABCD", but the uevent attribute of its platform device node is "platform:INTABCD:00" (PREFIX:platform_device->name). If this piece of code is used in an i2c driver for an ACPI enumerated i2c device, the i2c driver module_alias is "acpi:INTABCD", but the uevent of its i2c device node is "i2c:INTABCD:00" (PREFIX:i2c_client->name). If this piece of code is used in an spi driver for an ACPI enumerated spi device, the spi driver module_alias is "acpi:INTABCD", but the uevent of its spi device node is "spi:INTABCD" (PREFIX:spi_device->modalias). The reason why the module autoloading is not broken for now is that the uevent file of the ACPI device node is "acpi:INTABCD". Thus it is the ACPI device node creation that loads the platform/i2c/spi driver. So this is a problem that will affect us the day when the ACPI bus is removed from device model. This patch introduces two new APIs, one for exporting ACPI ids in uevent MODALIAS field, and another for exporting ACPI ids in device' modalias sysfs attribute. For any bus that supports ACPI enumerated devices, it needs to invoke these two functions for their uevent and modalias attribute. Signed-off-by: Zhang Rui <rui.zhang@intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-01-14 01:46:36 -07:00
sizeof(env->buf) - env->buflen);
if (len <= 0)
return len;
env->buflen += len;
return 0;
}
EXPORT_SYMBOL_GPL(acpi_device_uevent_modalias);
/*
* Creates modalias sysfs attribute for ACPI enumerated devices.
* Because the other buses does not support ACPI HIDs & CIDs.
* e.g. for a device with hid:IBM0001 and cid:ACPI0001 you get:
* "acpi:IBM0001:ACPI0001"
*/
int acpi_device_modalias(struct device *dev, char *buf, int size)
{
int len;
ACPI: Use ACPI companion to match only the first physical device Commit 6ab3430129e2 ("mfd: Add ACPI support") made the MFD subdevices share the parent MFD ACPI companion if no _HID/_CID is specified for the subdevice in mfd_cell description. However, since all the subdevices share the ACPI companion, the match and modalias generation logic started to use the ACPI companion as well resulting this: # cat /sys/bus/platform/devices/HID-SENSOR-200041.6.auto/modalias acpi:INT33D1:PNP0C50: instead of the expected one # cat /sys/bus/platform/devices/HID-SENSOR-200041.6.auto/modalias platform:HID-SENSOR-200041 In other words the subdevice modalias is overwritten by the one taken from ACPI companion. This causes udev not to load the driver anymore. It is useful to be able to share the ACPI companion so that MFD subdevices (and possibly other devices as well) can access the ACPI resources even if they do not have ACPI representation in the namespace themselves. An example where this is used is Minnowboard LPC driver that creates GPIO as a subdevice among other things. Without the ACPI companion gpiolib is not able to lookup the corresponding GPIO controller from ACPI GpioIo resource. To fix this, restrict the match and modalias logic to be limited to the first (primary) physical device associated with the given ACPI comapnion. The secondary devices will still be able to access the ACPI companion, but they will be matched in a different way. Fixes: 6ab3430129e2 (mfd: Add ACPI support) Reported-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-10-24 08:40:54 -06:00
if (!acpi_companion_match(dev))
ACPI: add module autoloading support for ACPI enumerated devices An ACPI enumerated device may have its compatible id strings. To support the compatible ACPI ids (acpi_device->pnp.ids), we introduced acpi_driver_match_device() to match the driver->acpi_match_table and acpi_device->pnp.ids. For those drivers, MODULE_DEVICE_TABLE(acpi, xxx) is used to exports the driver module alias in the format of "acpi:device_compatible_ids". But in the mean time, the current code does not export the ACPI compatible strings as part of the module_alias for the ACPI enumerated devices, which will break the module autoloading. Take the following piece of code for example, static const struct acpi_device_id xxx_acpi_match[] = { { "INTABCD", 0 }, { } }; MODULE_DEVICE_TABLE(acpi, xxx_acpi_match); If this piece of code is used in a platform driver for an ACPI enumerated platform device, the platform driver module_alias is "acpi:INTABCD", but the uevent attribute of its platform device node is "platform:INTABCD:00" (PREFIX:platform_device->name). If this piece of code is used in an i2c driver for an ACPI enumerated i2c device, the i2c driver module_alias is "acpi:INTABCD", but the uevent of its i2c device node is "i2c:INTABCD:00" (PREFIX:i2c_client->name). If this piece of code is used in an spi driver for an ACPI enumerated spi device, the spi driver module_alias is "acpi:INTABCD", but the uevent of its spi device node is "spi:INTABCD" (PREFIX:spi_device->modalias). The reason why the module autoloading is not broken for now is that the uevent file of the ACPI device node is "acpi:INTABCD". Thus it is the ACPI device node creation that loads the platform/i2c/spi driver. So this is a problem that will affect us the day when the ACPI bus is removed from device model. This patch introduces two new APIs, one for exporting ACPI ids in uevent MODALIAS field, and another for exporting ACPI ids in device' modalias sysfs attribute. For any bus that supports ACPI enumerated devices, it needs to invoke these two functions for their uevent and modalias attribute. Signed-off-by: Zhang Rui <rui.zhang@intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-01-14 01:46:36 -07:00
return -ENODEV;
ACPI: Use ACPI companion to match only the first physical device Commit 6ab3430129e2 ("mfd: Add ACPI support") made the MFD subdevices share the parent MFD ACPI companion if no _HID/_CID is specified for the subdevice in mfd_cell description. However, since all the subdevices share the ACPI companion, the match and modalias generation logic started to use the ACPI companion as well resulting this: # cat /sys/bus/platform/devices/HID-SENSOR-200041.6.auto/modalias acpi:INT33D1:PNP0C50: instead of the expected one # cat /sys/bus/platform/devices/HID-SENSOR-200041.6.auto/modalias platform:HID-SENSOR-200041 In other words the subdevice modalias is overwritten by the one taken from ACPI companion. This causes udev not to load the driver anymore. It is useful to be able to share the ACPI companion so that MFD subdevices (and possibly other devices as well) can access the ACPI resources even if they do not have ACPI representation in the namespace themselves. An example where this is used is Minnowboard LPC driver that creates GPIO as a subdevice among other things. Without the ACPI companion gpiolib is not able to lookup the corresponding GPIO controller from ACPI GpioIo resource. To fix this, restrict the match and modalias logic to be limited to the first (primary) physical device associated with the given ACPI comapnion. The secondary devices will still be able to access the ACPI companion, but they will be matched in a different way. Fixes: 6ab3430129e2 (mfd: Add ACPI support) Reported-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-10-24 08:40:54 -06:00
len = create_modalias(ACPI_COMPANION(dev), buf, size -1);
ACPI: add module autoloading support for ACPI enumerated devices An ACPI enumerated device may have its compatible id strings. To support the compatible ACPI ids (acpi_device->pnp.ids), we introduced acpi_driver_match_device() to match the driver->acpi_match_table and acpi_device->pnp.ids. For those drivers, MODULE_DEVICE_TABLE(acpi, xxx) is used to exports the driver module alias in the format of "acpi:device_compatible_ids". But in the mean time, the current code does not export the ACPI compatible strings as part of the module_alias for the ACPI enumerated devices, which will break the module autoloading. Take the following piece of code for example, static const struct acpi_device_id xxx_acpi_match[] = { { "INTABCD", 0 }, { } }; MODULE_DEVICE_TABLE(acpi, xxx_acpi_match); If this piece of code is used in a platform driver for an ACPI enumerated platform device, the platform driver module_alias is "acpi:INTABCD", but the uevent attribute of its platform device node is "platform:INTABCD:00" (PREFIX:platform_device->name). If this piece of code is used in an i2c driver for an ACPI enumerated i2c device, the i2c driver module_alias is "acpi:INTABCD", but the uevent of its i2c device node is "i2c:INTABCD:00" (PREFIX:i2c_client->name). If this piece of code is used in an spi driver for an ACPI enumerated spi device, the spi driver module_alias is "acpi:INTABCD", but the uevent of its spi device node is "spi:INTABCD" (PREFIX:spi_device->modalias). The reason why the module autoloading is not broken for now is that the uevent file of the ACPI device node is "acpi:INTABCD". Thus it is the ACPI device node creation that loads the platform/i2c/spi driver. So this is a problem that will affect us the day when the ACPI bus is removed from device model. This patch introduces two new APIs, one for exporting ACPI ids in uevent MODALIAS field, and another for exporting ACPI ids in device' modalias sysfs attribute. For any bus that supports ACPI enumerated devices, it needs to invoke these two functions for their uevent and modalias attribute. Signed-off-by: Zhang Rui <rui.zhang@intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-01-14 01:46:36 -07:00
if (len <= 0)
return len;
buf[len++] = '\n';
return len;
}
EXPORT_SYMBOL_GPL(acpi_device_modalias);
static ssize_t
acpi_device_modalias_show(struct device *dev, struct device_attribute *attr, char *buf) {
struct acpi_device *acpi_dev = to_acpi_device(dev);
int len;
len = create_modalias(acpi_dev, buf, 1024);
if (len <= 0)
return len;
buf[len++] = '\n';
return len;
}
static DEVICE_ATTR(modalias, 0444, acpi_device_modalias_show, NULL);
ACPI / hotplug / driver core: Handle containers in a special way ACPI container devices require special hotplug handling, at least on some systems, since generally user space needs to carry out system-specific cleanup before it makes sense to offline devices in the container. However, the current ACPI hotplug code for containers first attempts to offline devices in the container and only then it notifies user space of the container offline. Moreover, after commit 202317a573b2 (ACPI / scan: Add acpi_device objects for all device nodes in the namespace), ACPI device objects representing containers are present as long as the ACPI namespace nodes corresponding to them are present, which may be forever, even if the container devices are physically detached from the system (the return values of the corresponding _STA methods change in those cases, but generally the namespace nodes themselves are still there). Thus it is useful to introduce entities representing containers that will go away during container hot-unplug. The goal of this change is to address both the above issues. The idea is to create a "companion" container system device for each of the ACPI container device objects during the initial namespace scan or on a hotplug event making the container present. That system device will be unregistered on container removal. A new bus type for container devices is added for this purpose, because device offline and online operations need to be defined for them. The online operation is a trivial function that is always successful and the offline uses a callback pointed to by the container device's offline member. For ACPI containers that callback simply walks the list of ACPI device objects right below the container object (its children) and checks if all of their physical companion devices are offline. If that's not the case, it returns -EBUSY and the container system devivce cannot be put offline. Consequently, to put the container system device offline, it is necessary to put all of the physical devices depending on its ACPI companion object offline beforehand. Container system devices created for ACPI container objects are initially online. They are created by the container ACPI scan handler whose hotplug.demand_offline flag is set. That causes acpi_scan_hot_remove() to check if the companion container system device is offline before attempting to remove an ACPI container or any devices below it. If the check fails, a KOBJ_CHANGE uevent is emitted for the container system device in question and user space is expected to offline all devices below the container and the container itself in response to it. Then, user space can finalize the removal of the container with the help of its ACPI device object's eject attribute in sysfs. Tested-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-12-29 07:25:48 -07:00
bool acpi_scan_is_offline(struct acpi_device *adev, bool uevent)
{
struct acpi_device_physical_node *pn;
bool offline = true;
mutex_lock(&adev->physical_node_lock);
list_for_each_entry(pn, &adev->physical_node_list, node)
if (device_supports_offline(pn->dev) && !pn->dev->offline) {
ACPI / hotplug / driver core: Handle containers in a special way ACPI container devices require special hotplug handling, at least on some systems, since generally user space needs to carry out system-specific cleanup before it makes sense to offline devices in the container. However, the current ACPI hotplug code for containers first attempts to offline devices in the container and only then it notifies user space of the container offline. Moreover, after commit 202317a573b2 (ACPI / scan: Add acpi_device objects for all device nodes in the namespace), ACPI device objects representing containers are present as long as the ACPI namespace nodes corresponding to them are present, which may be forever, even if the container devices are physically detached from the system (the return values of the corresponding _STA methods change in those cases, but generally the namespace nodes themselves are still there). Thus it is useful to introduce entities representing containers that will go away during container hot-unplug. The goal of this change is to address both the above issues. The idea is to create a "companion" container system device for each of the ACPI container device objects during the initial namespace scan or on a hotplug event making the container present. That system device will be unregistered on container removal. A new bus type for container devices is added for this purpose, because device offline and online operations need to be defined for them. The online operation is a trivial function that is always successful and the offline uses a callback pointed to by the container device's offline member. For ACPI containers that callback simply walks the list of ACPI device objects right below the container object (its children) and checks if all of their physical companion devices are offline. If that's not the case, it returns -EBUSY and the container system devivce cannot be put offline. Consequently, to put the container system device offline, it is necessary to put all of the physical devices depending on its ACPI companion object offline beforehand. Container system devices created for ACPI container objects are initially online. They are created by the container ACPI scan handler whose hotplug.demand_offline flag is set. That causes acpi_scan_hot_remove() to check if the companion container system device is offline before attempting to remove an ACPI container or any devices below it. If the check fails, a KOBJ_CHANGE uevent is emitted for the container system device in question and user space is expected to offline all devices below the container and the container itself in response to it. Then, user space can finalize the removal of the container with the help of its ACPI device object's eject attribute in sysfs. Tested-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-12-29 07:25:48 -07:00
if (uevent)
kobject_uevent(&pn->dev->kobj, KOBJ_CHANGE);
offline = false;
break;
}
mutex_unlock(&adev->physical_node_lock);
return offline;
}
static acpi_status acpi_bus_offline(acpi_handle handle, u32 lvl, void *data,
void **ret_p)
{
struct acpi_device *device = NULL;
struct acpi_device_physical_node *pn;
bool second_pass = (bool)data;
acpi_status status = AE_OK;
if (acpi_bus_get_device(handle, &device))
return AE_OK;
if (device->handler && !device->handler->hotplug.enabled) {
*ret_p = &device->dev;
return AE_SUPPORT;
}
mutex_lock(&device->physical_node_lock);
list_for_each_entry(pn, &device->physical_node_list, node) {
int ret;
if (second_pass) {
/* Skip devices offlined by the first pass. */
if (pn->put_online)
continue;
} else {
pn->put_online = false;
}
ret = device_offline(pn->dev);
if (acpi_force_hot_remove)
continue;
if (ret >= 0) {
pn->put_online = !ret;
} else {
*ret_p = pn->dev;
if (second_pass) {
status = AE_ERROR;
break;
}
}
}
mutex_unlock(&device->physical_node_lock);
return status;
}
static acpi_status acpi_bus_online(acpi_handle handle, u32 lvl, void *data,
void **ret_p)
{
struct acpi_device *device = NULL;
struct acpi_device_physical_node *pn;
if (acpi_bus_get_device(handle, &device))
return AE_OK;
mutex_lock(&device->physical_node_lock);
list_for_each_entry(pn, &device->physical_node_list, node)
if (pn->put_online) {
device_online(pn->dev);
pn->put_online = false;
}
mutex_unlock(&device->physical_node_lock);
return AE_OK;
}
static int acpi_scan_try_to_offline(struct acpi_device *device)
{
acpi_handle handle = device->handle;
struct device *errdev = NULL;
acpi_status status;
/*
* Carry out two passes here and ignore errors in the first pass,
* because if the devices in question are memory blocks and
* CONFIG_MEMCG is set, one of the blocks may hold data structures
* that the other blocks depend on, but it is not known in advance which
* block holds them.
*
* If the first pass is successful, the second one isn't needed, though.
*/
status = acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
NULL, acpi_bus_offline, (void *)false,
(void **)&errdev);
if (status == AE_SUPPORT) {
dev_warn(errdev, "Offline disabled.\n");
acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
acpi_bus_online, NULL, NULL, NULL);
return -EPERM;
}
acpi_bus_offline(handle, 0, (void *)false, (void **)&errdev);
if (errdev) {
errdev = NULL;
acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
NULL, acpi_bus_offline, (void *)true,
(void **)&errdev);
if (!errdev || acpi_force_hot_remove)
acpi_bus_offline(handle, 0, (void *)true,
(void **)&errdev);
if (errdev && !acpi_force_hot_remove) {
dev_warn(errdev, "Offline failed.\n");
acpi_bus_online(handle, 0, NULL, NULL);
acpi_walk_namespace(ACPI_TYPE_ANY, handle,
ACPI_UINT32_MAX, acpi_bus_online,
NULL, NULL, NULL);
return -EBUSY;
}
}
return 0;
}
static int acpi_scan_hot_remove(struct acpi_device *device)
{
acpi_handle handle = device->handle;
unsigned long long sta;
acpi_status status;
ACPI / hotplug: Check scan handlers in acpi_scan_hot_remove() When ACPI_HOTPLUG_MEMORY is not configured, memory_device_handler.attach is not set. In acpi_scan_attach_handler(), the acpi_device->handler will not be initialized. In acpi_scan_hot_remove(), it doesn't check if acpi_device->handler is NULL. If we do memory hot-remove without ACPI_HOTPLUG_MEMORY configured, the kernel will panic. BUG: unable to handle kernel NULL pointer dereference at 0000000000000088 IP: [<ffffffff813e318f>] acpi_device_hotplug+0x1d7/0x4c4 PGD 0 Oops: 0000 [#1] SMP Modules linked in: sd_mod(E) sr_mod(E) cdrom(E) crc_t10dif(E) crct10dif_common(E) ata_piix(E) libata(E) CPU: 0 PID: 41 Comm: kworker/u2:1 Tainted: G E 3.16.0-rc7--3.16-rc7-tangchen+ #20 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.7.5-0-ge51488c-20140602_164612-nilsson.home.kraxel.org 04/01/2014 Workqueue: kacpi_hotplug acpi_hotplug_work_fn task: ffff8800182436c0 ti: ffff880018254000 task.ti: ffff880018254000 RIP: 0010:[<ffffffff813e318f>] [<ffffffff813e318f>] acpi_device_hotplug+0x1d7/0x4c4 RSP: 0000:ffff880018257da8 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffff88001cd8d800 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffff88001e40e6f8 RDI: 0000000000000246 RBP: ffff880018257df0 R08: 0000000000000096 R09: 00000000000011a0 R10: 63735f6970636120 R11: 725f746f685f6e61 R12: 0000000000000003 R13: ffff88001cc1c400 R14: ffff88001e062028 R15: 0000000000000040 FS: 0000000000000000(0000) GS:ffff88001e400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: 0000000000000088 CR3: 000000001a9a2000 CR4: 00000000000006f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 0000000000000000 DR7: 0000000000000000 Stack: 00000000523cab58 ffff88001cd8d9f8 ffff88001852d480 00000000523cab58 ffff88001852d480 ffff880018221e40 ffff88001cc1c400 ffff88001cce2d00 0000000000000040 ffff880018257e08 ffffffff813dc31d ffff88001852d480 Call Trace: [<ffffffff813dc31d>] acpi_hotplug_work_fn+0x1e/0x29 [<ffffffff8108eefb>] process_one_work+0x17b/0x460 [<ffffffff8108f69d>] worker_thread+0x11d/0x5b0 [<ffffffff8108f580>] ? rescuer_thread+0x3a0/0x3a0 [<ffffffff81096811>] kthread+0xe1/0x100 [<ffffffff81096730>] ? kthread_create_on_node+0x1a0/0x1a0 [<ffffffff816cc6bc>] ret_from_fork+0x7c/0xb0 [<ffffffff81096730>] ? kthread_create_on_node+0x1a0/0x1a0 This patch fixes this problem by checking if acpi_device->handler is NULL in acpi_scan_hot_remove(). Fixes: d22ddcbc4fb7 (ACPI / hotplug: Add demand_offline hotplug profile flag) Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> Cc: 3.14+ <stable@vger.kernel.org> # 3.14+ [rjw: Subject] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-08-07 20:30:45 -06:00
if (device->handler && device->handler->hotplug.demand_offline
&& !acpi_force_hot_remove) {
ACPI / hotplug / driver core: Handle containers in a special way ACPI container devices require special hotplug handling, at least on some systems, since generally user space needs to carry out system-specific cleanup before it makes sense to offline devices in the container. However, the current ACPI hotplug code for containers first attempts to offline devices in the container and only then it notifies user space of the container offline. Moreover, after commit 202317a573b2 (ACPI / scan: Add acpi_device objects for all device nodes in the namespace), ACPI device objects representing containers are present as long as the ACPI namespace nodes corresponding to them are present, which may be forever, even if the container devices are physically detached from the system (the return values of the corresponding _STA methods change in those cases, but generally the namespace nodes themselves are still there). Thus it is useful to introduce entities representing containers that will go away during container hot-unplug. The goal of this change is to address both the above issues. The idea is to create a "companion" container system device for each of the ACPI container device objects during the initial namespace scan or on a hotplug event making the container present. That system device will be unregistered on container removal. A new bus type for container devices is added for this purpose, because device offline and online operations need to be defined for them. The online operation is a trivial function that is always successful and the offline uses a callback pointed to by the container device's offline member. For ACPI containers that callback simply walks the list of ACPI device objects right below the container object (its children) and checks if all of their physical companion devices are offline. If that's not the case, it returns -EBUSY and the container system devivce cannot be put offline. Consequently, to put the container system device offline, it is necessary to put all of the physical devices depending on its ACPI companion object offline beforehand. Container system devices created for ACPI container objects are initially online. They are created by the container ACPI scan handler whose hotplug.demand_offline flag is set. That causes acpi_scan_hot_remove() to check if the companion container system device is offline before attempting to remove an ACPI container or any devices below it. If the check fails, a KOBJ_CHANGE uevent is emitted for the container system device in question and user space is expected to offline all devices below the container and the container itself in response to it. Then, user space can finalize the removal of the container with the help of its ACPI device object's eject attribute in sysfs. Tested-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-12-29 07:25:48 -07:00
if (!acpi_scan_is_offline(device, true))
return -EBUSY;
} else {
int error = acpi_scan_try_to_offline(device);
if (error)
return error;
}
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
"Hot-removing device %s...\n", dev_name(&device->dev)));
acpi_bus_trim(device);
acpi_evaluate_lck(handle, 0);
/*
* TBD: _EJD support.
*/
status = acpi_evaluate_ej0(handle);
if (status == AE_NOT_FOUND)
return -ENODEV;
else if (ACPI_FAILURE(status))
return -EIO;
/*
* Verify if eject was indeed successful. If not, log an error
* message. No need to call _OST since _EJ0 call was made OK.
*/
status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
if (ACPI_FAILURE(status)) {
acpi_handle_warn(handle,
"Status check after eject failed (0x%x)\n", status);
} else if (sta & ACPI_STA_DEVICE_ENABLED) {
acpi_handle_warn(handle,
"Eject incomplete - status 0x%llx\n", sta);
}
return 0;
}
static int acpi_scan_device_not_present(struct acpi_device *adev)
{
if (!acpi_device_enumerated(adev)) {
dev_warn(&adev->dev, "Still not present\n");
return -EALREADY;
}
acpi_bus_trim(adev);
return 0;
}
static int acpi_scan_device_check(struct acpi_device *adev)
{
ACPI / hotplug: Remove containers synchronously The current protocol for handling hot remove of containers is very fragile and causes acpi_eject_store() to acquire acpi_scan_lock which may deadlock with the removal of the device that it is called for (the reason is that device sysfs attributes cannot be removed while their callbacks are being executed and ACPI device objects are removed under acpi_scan_lock). The problem is related to the fact that containers are handled by acpi_bus_device_eject() in a special way, which is to emit an offline uevent instead of just removing the container. Then, user space is expected to handle that uevent and use the container's "eject" attribute to actually remove it. That is fragile, because user space may fail to complete the ejection (for example, by not using the container's "eject" attribute at all) leaving the BIOS kind of in a limbo. Moreover, if the eject event is not signaled for a container itself, but for its parent device object (or generally, for an ancestor above it in the ACPI namespace), the container will be removed straight away without doing that whole dance. For this reason, modify acpi_bus_device_eject() to remove containers synchronously like any other objects (user space will get its uevent anyway in case it does some other things in response to it) and remove the eject_pending ACPI device flag that is not used any more. This way acpi_eject_store() doesn't have a reason to acquire acpi_scan_lock any more and one possible deadlock scenario goes away (plus the code is simplified a bit). Reported-and-tested-by: Gu Zheng <guz.fnst@cn.fujitsu.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Toshi Kani <toshi.kani@hp.com>
2013-08-28 13:41:07 -06:00
int error;
acpi_bus_get_status(adev);
if (adev->status.present || adev->status.functional) {
/*
* This function is only called for device objects for which
* matching scan handlers exist. The only situation in which
* the scan handler is not attached to this device object yet
* is when the device has just appeared (either it wasn't
* present at all before or it was removed and then added
* again).
*/
if (adev->handler) {
dev_warn(&adev->dev, "Already enumerated\n");
return -EALREADY;
}
error = acpi_bus_scan(adev->handle);
if (error) {
dev_warn(&adev->dev, "Namespace scan failure\n");
return error;
}
if (!adev->handler) {
dev_warn(&adev->dev, "Enumeration failure\n");
error = -ENODEV;
}
} else {
error = acpi_scan_device_not_present(adev);
}
return error;
}
static int acpi_scan_bus_check(struct acpi_device *adev)
{
struct acpi_scan_handler *handler = adev->handler;
struct acpi_device *child;
int error;
acpi_bus_get_status(adev);
if (!(adev->status.present || adev->status.functional)) {
acpi_scan_device_not_present(adev);
return 0;
}
if (handler && handler->hotplug.scan_dependent)
return handler->hotplug.scan_dependent(adev);
error = acpi_bus_scan(adev->handle);
if (error) {
dev_warn(&adev->dev, "Namespace scan failure\n");
return error;
}
list_for_each_entry(child, &adev->children, node) {
error = acpi_scan_bus_check(child);
if (error)
return error;
}
return 0;
}
ACPI / hotplug / PCI: Consolidate ACPIPHP with ACPI core hotplug The ACPI-based PCI hotplug (ACPIPHP) code currently attaches its hotplug context objects directly to ACPI namespace nodes representing hotplug devices. However, after recent changes causing struct acpi_device to be created for every namespace node representing a device (regardless of its status), that is not necessary any more. Moreover, it's vulnerable to the theoretical issue that the ACPI handle passed in the context between handle_hotplug_event() and hotplug_event_work() may become invalid in the meantime (as a result of a concurrent table unload). In principle, this issue might be addressed by adding a non-empty release handler for ACPIPHP hotplug context objects analogous to acpi_scan_drop_device(), but that would duplicate the code in that function and in acpi_device_del_work_fn(). For this reason, it's better to modify ACPIPHP to attach its device hotplug contexts to struct device objects representing hotplug devices and make it use acpi_hotplug_notify_cb() as its notify handler. At the same time, acpi_device_hotplug() can be modified to dispatch the new .hp.event() callback pointing to acpiphp_hotplug_event() from ACPI device objects associated with PCI devices or use the generic ACPI device hotplug code for device objects with matching scan handlers. This allows the existing code duplication between ACPIPHP and the ACPI core to be reduced too and makes further ACPI-based device hotplug consolidation possible. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-06 09:31:37 -07:00
static int acpi_generic_hotplug_event(struct acpi_device *adev, u32 type)
{
switch (type) {
case ACPI_NOTIFY_BUS_CHECK:
return acpi_scan_bus_check(adev);
case ACPI_NOTIFY_DEVICE_CHECK:
return acpi_scan_device_check(adev);
case ACPI_NOTIFY_EJECT_REQUEST:
case ACPI_OST_EC_OSPM_EJECT:
if (adev->handler && !adev->handler->hotplug.enabled) {
dev_info(&adev->dev, "Eject disabled\n");
return -EPERM;
}
acpi_evaluate_ost(adev->handle, ACPI_NOTIFY_EJECT_REQUEST,
ACPI_OST_SC_EJECT_IN_PROGRESS, NULL);
ACPI / hotplug / PCI: Consolidate ACPIPHP with ACPI core hotplug The ACPI-based PCI hotplug (ACPIPHP) code currently attaches its hotplug context objects directly to ACPI namespace nodes representing hotplug devices. However, after recent changes causing struct acpi_device to be created for every namespace node representing a device (regardless of its status), that is not necessary any more. Moreover, it's vulnerable to the theoretical issue that the ACPI handle passed in the context between handle_hotplug_event() and hotplug_event_work() may become invalid in the meantime (as a result of a concurrent table unload). In principle, this issue might be addressed by adding a non-empty release handler for ACPIPHP hotplug context objects analogous to acpi_scan_drop_device(), but that would duplicate the code in that function and in acpi_device_del_work_fn(). For this reason, it's better to modify ACPIPHP to attach its device hotplug contexts to struct device objects representing hotplug devices and make it use acpi_hotplug_notify_cb() as its notify handler. At the same time, acpi_device_hotplug() can be modified to dispatch the new .hp.event() callback pointing to acpiphp_hotplug_event() from ACPI device objects associated with PCI devices or use the generic ACPI device hotplug code for device objects with matching scan handlers. This allows the existing code duplication between ACPIPHP and the ACPI core to be reduced too and makes further ACPI-based device hotplug consolidation possible. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-06 09:31:37 -07:00
return acpi_scan_hot_remove(adev);
}
return -EINVAL;
}
void acpi_device_hotplug(struct acpi_device *adev, u32 src)
{
u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
ACPI / hotplug / PCI: Consolidate ACPIPHP with ACPI core hotplug The ACPI-based PCI hotplug (ACPIPHP) code currently attaches its hotplug context objects directly to ACPI namespace nodes representing hotplug devices. However, after recent changes causing struct acpi_device to be created for every namespace node representing a device (regardless of its status), that is not necessary any more. Moreover, it's vulnerable to the theoretical issue that the ACPI handle passed in the context between handle_hotplug_event() and hotplug_event_work() may become invalid in the meantime (as a result of a concurrent table unload). In principle, this issue might be addressed by adding a non-empty release handler for ACPIPHP hotplug context objects analogous to acpi_scan_drop_device(), but that would duplicate the code in that function and in acpi_device_del_work_fn(). For this reason, it's better to modify ACPIPHP to attach its device hotplug contexts to struct device objects representing hotplug devices and make it use acpi_hotplug_notify_cb() as its notify handler. At the same time, acpi_device_hotplug() can be modified to dispatch the new .hp.event() callback pointing to acpiphp_hotplug_event() from ACPI device objects associated with PCI devices or use the generic ACPI device hotplug code for device objects with matching scan handlers. This allows the existing code duplication between ACPIPHP and the ACPI core to be reduced too and makes further ACPI-based device hotplug consolidation possible. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-06 09:31:37 -07:00
int error = -ENODEV;
lock_device_hotplug();
mutex_lock(&acpi_scan_lock);
/*
* The device object's ACPI handle cannot become invalid as long as we
ACPI / hotplug / PCI: Consolidate ACPIPHP with ACPI core hotplug The ACPI-based PCI hotplug (ACPIPHP) code currently attaches its hotplug context objects directly to ACPI namespace nodes representing hotplug devices. However, after recent changes causing struct acpi_device to be created for every namespace node representing a device (regardless of its status), that is not necessary any more. Moreover, it's vulnerable to the theoretical issue that the ACPI handle passed in the context between handle_hotplug_event() and hotplug_event_work() may become invalid in the meantime (as a result of a concurrent table unload). In principle, this issue might be addressed by adding a non-empty release handler for ACPIPHP hotplug context objects analogous to acpi_scan_drop_device(), but that would duplicate the code in that function and in acpi_device_del_work_fn(). For this reason, it's better to modify ACPIPHP to attach its device hotplug contexts to struct device objects representing hotplug devices and make it use acpi_hotplug_notify_cb() as its notify handler. At the same time, acpi_device_hotplug() can be modified to dispatch the new .hp.event() callback pointing to acpiphp_hotplug_event() from ACPI device objects associated with PCI devices or use the generic ACPI device hotplug code for device objects with matching scan handlers. This allows the existing code duplication between ACPIPHP and the ACPI core to be reduced too and makes further ACPI-based device hotplug consolidation possible. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-06 09:31:37 -07:00
* are holding acpi_scan_lock, but it might have become invalid before
* that lock was acquired.
*/
if (adev->handle == INVALID_ACPI_HANDLE)
ACPI / hotplug / PCI: Consolidate ACPIPHP with ACPI core hotplug The ACPI-based PCI hotplug (ACPIPHP) code currently attaches its hotplug context objects directly to ACPI namespace nodes representing hotplug devices. However, after recent changes causing struct acpi_device to be created for every namespace node representing a device (regardless of its status), that is not necessary any more. Moreover, it's vulnerable to the theoretical issue that the ACPI handle passed in the context between handle_hotplug_event() and hotplug_event_work() may become invalid in the meantime (as a result of a concurrent table unload). In principle, this issue might be addressed by adding a non-empty release handler for ACPIPHP hotplug context objects analogous to acpi_scan_drop_device(), but that would duplicate the code in that function and in acpi_device_del_work_fn(). For this reason, it's better to modify ACPIPHP to attach its device hotplug contexts to struct device objects representing hotplug devices and make it use acpi_hotplug_notify_cb() as its notify handler. At the same time, acpi_device_hotplug() can be modified to dispatch the new .hp.event() callback pointing to acpiphp_hotplug_event() from ACPI device objects associated with PCI devices or use the generic ACPI device hotplug code for device objects with matching scan handlers. This allows the existing code duplication between ACPIPHP and the ACPI core to be reduced too and makes further ACPI-based device hotplug consolidation possible. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-06 09:31:37 -07:00
goto err_out;
ACPI / dock: Dispatch dock notifications from the global notify handler The ACPI dock station code carries out an extra namespace scan before the main one in order to find and register all of the dock device objects. Then, it registers a notify handler for each of them for handling dock events. However, dock device objects need not be scanned for upfront. They very well can be enumerated and registered during the first phase of the main namespace scan, before attaching scan handlers and ACPI drivers to ACPI device objects. Then, the dependent devices can be added to the in the second phase. That makes it possible to drop the extra namespace scan, so do it. Moreover, it is not necessary to register notify handlers for all of the dock stations' namespace nodes, becuase notifications may be dispatched from the global notify handler for them. Do that and drop two functions used for dock notify handling, acpi_dock_deferred_cb() and dock_notify_handler(), that aren't necessary any more. Finally, some dock station objects have _HID objects matching the ACPI container scan handler which causes it to claim those objects and try to handle their hotplug, but that is not a good idea, because those objects have their own special hotplug handling anyway. For this reason, the hotplug_notify flag should not be set for ACPI device objects representing dock stations and the container scan handler should be made ignore those objects, so make that happen. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-15 17:51:01 -07:00
if (adev->flags.is_dock_station) {
error = dock_notify(adev, src);
} else if (adev->flags.hotplug_notify) {
ACPI / hotplug / PCI: Consolidate ACPIPHP with ACPI core hotplug The ACPI-based PCI hotplug (ACPIPHP) code currently attaches its hotplug context objects directly to ACPI namespace nodes representing hotplug devices. However, after recent changes causing struct acpi_device to be created for every namespace node representing a device (regardless of its status), that is not necessary any more. Moreover, it's vulnerable to the theoretical issue that the ACPI handle passed in the context between handle_hotplug_event() and hotplug_event_work() may become invalid in the meantime (as a result of a concurrent table unload). In principle, this issue might be addressed by adding a non-empty release handler for ACPIPHP hotplug context objects analogous to acpi_scan_drop_device(), but that would duplicate the code in that function and in acpi_device_del_work_fn(). For this reason, it's better to modify ACPIPHP to attach its device hotplug contexts to struct device objects representing hotplug devices and make it use acpi_hotplug_notify_cb() as its notify handler. At the same time, acpi_device_hotplug() can be modified to dispatch the new .hp.event() callback pointing to acpiphp_hotplug_event() from ACPI device objects associated with PCI devices or use the generic ACPI device hotplug code for device objects with matching scan handlers. This allows the existing code duplication between ACPIPHP and the ACPI core to be reduced too and makes further ACPI-based device hotplug consolidation possible. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-06 09:31:37 -07:00
error = acpi_generic_hotplug_event(adev, src);
if (error == -EPERM) {
ost_code = ACPI_OST_SC_EJECT_NOT_SUPPORTED;
goto err_out;
}
ACPI / hotplug / PCI: Consolidate ACPIPHP with ACPI core hotplug The ACPI-based PCI hotplug (ACPIPHP) code currently attaches its hotplug context objects directly to ACPI namespace nodes representing hotplug devices. However, after recent changes causing struct acpi_device to be created for every namespace node representing a device (regardless of its status), that is not necessary any more. Moreover, it's vulnerable to the theoretical issue that the ACPI handle passed in the context between handle_hotplug_event() and hotplug_event_work() may become invalid in the meantime (as a result of a concurrent table unload). In principle, this issue might be addressed by adding a non-empty release handler for ACPIPHP hotplug context objects analogous to acpi_scan_drop_device(), but that would duplicate the code in that function and in acpi_device_del_work_fn(). For this reason, it's better to modify ACPIPHP to attach its device hotplug contexts to struct device objects representing hotplug devices and make it use acpi_hotplug_notify_cb() as its notify handler. At the same time, acpi_device_hotplug() can be modified to dispatch the new .hp.event() callback pointing to acpiphp_hotplug_event() from ACPI device objects associated with PCI devices or use the generic ACPI device hotplug code for device objects with matching scan handlers. This allows the existing code duplication between ACPIPHP and the ACPI core to be reduced too and makes further ACPI-based device hotplug consolidation possible. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-06 09:31:37 -07:00
} else {
int (*notify)(struct acpi_device *, u32);
ACPI / hotplug / PCI: Consolidate ACPIPHP with ACPI core hotplug The ACPI-based PCI hotplug (ACPIPHP) code currently attaches its hotplug context objects directly to ACPI namespace nodes representing hotplug devices. However, after recent changes causing struct acpi_device to be created for every namespace node representing a device (regardless of its status), that is not necessary any more. Moreover, it's vulnerable to the theoretical issue that the ACPI handle passed in the context between handle_hotplug_event() and hotplug_event_work() may become invalid in the meantime (as a result of a concurrent table unload). In principle, this issue might be addressed by adding a non-empty release handler for ACPIPHP hotplug context objects analogous to acpi_scan_drop_device(), but that would duplicate the code in that function and in acpi_device_del_work_fn(). For this reason, it's better to modify ACPIPHP to attach its device hotplug contexts to struct device objects representing hotplug devices and make it use acpi_hotplug_notify_cb() as its notify handler. At the same time, acpi_device_hotplug() can be modified to dispatch the new .hp.event() callback pointing to acpiphp_hotplug_event() from ACPI device objects associated with PCI devices or use the generic ACPI device hotplug code for device objects with matching scan handlers. This allows the existing code duplication between ACPIPHP and the ACPI core to be reduced too and makes further ACPI-based device hotplug consolidation possible. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-06 09:31:37 -07:00
acpi_lock_hp_context();
notify = adev->hp ? adev->hp->notify : NULL;
ACPI / hotplug / PCI: Consolidate ACPIPHP with ACPI core hotplug The ACPI-based PCI hotplug (ACPIPHP) code currently attaches its hotplug context objects directly to ACPI namespace nodes representing hotplug devices. However, after recent changes causing struct acpi_device to be created for every namespace node representing a device (regardless of its status), that is not necessary any more. Moreover, it's vulnerable to the theoretical issue that the ACPI handle passed in the context between handle_hotplug_event() and hotplug_event_work() may become invalid in the meantime (as a result of a concurrent table unload). In principle, this issue might be addressed by adding a non-empty release handler for ACPIPHP hotplug context objects analogous to acpi_scan_drop_device(), but that would duplicate the code in that function and in acpi_device_del_work_fn(). For this reason, it's better to modify ACPIPHP to attach its device hotplug contexts to struct device objects representing hotplug devices and make it use acpi_hotplug_notify_cb() as its notify handler. At the same time, acpi_device_hotplug() can be modified to dispatch the new .hp.event() callback pointing to acpiphp_hotplug_event() from ACPI device objects associated with PCI devices or use the generic ACPI device hotplug code for device objects with matching scan handlers. This allows the existing code duplication between ACPIPHP and the ACPI core to be reduced too and makes further ACPI-based device hotplug consolidation possible. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-06 09:31:37 -07:00
acpi_unlock_hp_context();
/*
* There may be additional notify handlers for device objects
* without the .event() callback, so ignore them here.
*/
if (notify)
error = notify(adev, src);
ACPI / hotplug / PCI: Consolidate ACPIPHP with ACPI core hotplug The ACPI-based PCI hotplug (ACPIPHP) code currently attaches its hotplug context objects directly to ACPI namespace nodes representing hotplug devices. However, after recent changes causing struct acpi_device to be created for every namespace node representing a device (regardless of its status), that is not necessary any more. Moreover, it's vulnerable to the theoretical issue that the ACPI handle passed in the context between handle_hotplug_event() and hotplug_event_work() may become invalid in the meantime (as a result of a concurrent table unload). In principle, this issue might be addressed by adding a non-empty release handler for ACPIPHP hotplug context objects analogous to acpi_scan_drop_device(), but that would duplicate the code in that function and in acpi_device_del_work_fn(). For this reason, it's better to modify ACPIPHP to attach its device hotplug contexts to struct device objects representing hotplug devices and make it use acpi_hotplug_notify_cb() as its notify handler. At the same time, acpi_device_hotplug() can be modified to dispatch the new .hp.event() callback pointing to acpiphp_hotplug_event() from ACPI device objects associated with PCI devices or use the generic ACPI device hotplug code for device objects with matching scan handlers. This allows the existing code duplication between ACPIPHP and the ACPI core to be reduced too and makes further ACPI-based device hotplug consolidation possible. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-06 09:31:37 -07:00
else
goto out;
}
if (!error)
ost_code = ACPI_OST_SC_SUCCESS;
ACPI / hotplug / PCI: Consolidate ACPIPHP with ACPI core hotplug The ACPI-based PCI hotplug (ACPIPHP) code currently attaches its hotplug context objects directly to ACPI namespace nodes representing hotplug devices. However, after recent changes causing struct acpi_device to be created for every namespace node representing a device (regardless of its status), that is not necessary any more. Moreover, it's vulnerable to the theoretical issue that the ACPI handle passed in the context between handle_hotplug_event() and hotplug_event_work() may become invalid in the meantime (as a result of a concurrent table unload). In principle, this issue might be addressed by adding a non-empty release handler for ACPIPHP hotplug context objects analogous to acpi_scan_drop_device(), but that would duplicate the code in that function and in acpi_device_del_work_fn(). For this reason, it's better to modify ACPIPHP to attach its device hotplug contexts to struct device objects representing hotplug devices and make it use acpi_hotplug_notify_cb() as its notify handler. At the same time, acpi_device_hotplug() can be modified to dispatch the new .hp.event() callback pointing to acpiphp_hotplug_event() from ACPI device objects associated with PCI devices or use the generic ACPI device hotplug code for device objects with matching scan handlers. This allows the existing code duplication between ACPIPHP and the ACPI core to be reduced too and makes further ACPI-based device hotplug consolidation possible. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-06 09:31:37 -07:00
err_out:
acpi_evaluate_ost(adev->handle, src, ost_code, NULL);
ACPI / hotplug / PCI: Consolidate ACPIPHP with ACPI core hotplug The ACPI-based PCI hotplug (ACPIPHP) code currently attaches its hotplug context objects directly to ACPI namespace nodes representing hotplug devices. However, after recent changes causing struct acpi_device to be created for every namespace node representing a device (regardless of its status), that is not necessary any more. Moreover, it's vulnerable to the theoretical issue that the ACPI handle passed in the context between handle_hotplug_event() and hotplug_event_work() may become invalid in the meantime (as a result of a concurrent table unload). In principle, this issue might be addressed by adding a non-empty release handler for ACPIPHP hotplug context objects analogous to acpi_scan_drop_device(), but that would duplicate the code in that function and in acpi_device_del_work_fn(). For this reason, it's better to modify ACPIPHP to attach its device hotplug contexts to struct device objects representing hotplug devices and make it use acpi_hotplug_notify_cb() as its notify handler. At the same time, acpi_device_hotplug() can be modified to dispatch the new .hp.event() callback pointing to acpiphp_hotplug_event() from ACPI device objects associated with PCI devices or use the generic ACPI device hotplug code for device objects with matching scan handlers. This allows the existing code duplication between ACPIPHP and the ACPI core to be reduced too and makes further ACPI-based device hotplug consolidation possible. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-06 09:31:37 -07:00
out:
ACPI / hotplug: Fix potential race in acpi_bus_notify() There is a slight possibility for the ACPI device object pointed to by adev in acpi_hotplug_notify_cb() to become invalid between the acpi_bus_get_device() that it comes from and the subsequent dereference of that pointer under get_device(). Namely, if acpi_scan_drop_device() runs in parallel with acpi_hotplug_notify_cb(), acpi_device_del_work_fn() queued up by it may delete the device object in question right after a successful execution of acpi_bus_get_device() in acpi_bus_notify(). An analogous problem is present in acpi_bus_notify() where the device pointer coming from acpi_bus_get_device() may become invalid before it subsequent dereference in the "if" block. To prevent that from happening, introduce a new function, acpi_bus_get_acpi_device(), working analogously to acpi_bus_get_device() except that it will grab a reference to the ACPI device object returned by it and it will do that under the ACPICA's namespace mutex. Then, make both acpi_hotplug_notify_cb() and acpi_bus_notify() use acpi_bus_get_acpi_device() instead of acpi_bus_get_device() so as to ensure that the pointers used by them will not become stale at one point. In addition to that, introduce acpi_bus_put_acpi_device() as a wrapper around put_device() to be used along with acpi_bus_get_acpi_device() and make the (new) users of the latter use acpi_bus_put_acpi_device() too. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2014-02-03 16:43:05 -07:00
acpi_bus_put_acpi_device(adev);
mutex_unlock(&acpi_scan_lock);
unlock_device_hotplug();
}
static ssize_t real_power_state_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct acpi_device *adev = to_acpi_device(dev);
int state;
int ret;
ret = acpi_device_get_power(adev, &state);
if (ret)
return ret;
return sprintf(buf, "%s\n", acpi_power_state_string(state));
}
static DEVICE_ATTR(real_power_state, 0444, real_power_state_show, NULL);
static ssize_t power_state_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct acpi_device *adev = to_acpi_device(dev);
return sprintf(buf, "%s\n", acpi_power_state_string(adev->power.state));
}
static DEVICE_ATTR(power_state, 0444, power_state_show, NULL);
static ssize_t
acpi_eject_store(struct device *d, struct device_attribute *attr,
const char *buf, size_t count)
{
struct acpi_device *acpi_device = to_acpi_device(d);
acpi_object_type not_used;
acpi_status status;
if (!count || buf[0] != '1')
return -EINVAL;
if ((!acpi_device->handler || !acpi_device->handler->hotplug.enabled)
&& !acpi_device->driver)
return -ENODEV;
status = acpi_get_type(acpi_device->handle, &not_used);
if (ACPI_FAILURE(status) || !acpi_device->flags.ejectable)
return -ENODEV;
get_device(&acpi_device->dev);
status = acpi_hotplug_schedule(acpi_device, ACPI_OST_EC_OSPM_EJECT);
ACPI / hotplug: Remove containers synchronously The current protocol for handling hot remove of containers is very fragile and causes acpi_eject_store() to acquire acpi_scan_lock which may deadlock with the removal of the device that it is called for (the reason is that device sysfs attributes cannot be removed while their callbacks are being executed and ACPI device objects are removed under acpi_scan_lock). The problem is related to the fact that containers are handled by acpi_bus_device_eject() in a special way, which is to emit an offline uevent instead of just removing the container. Then, user space is expected to handle that uevent and use the container's "eject" attribute to actually remove it. That is fragile, because user space may fail to complete the ejection (for example, by not using the container's "eject" attribute at all) leaving the BIOS kind of in a limbo. Moreover, if the eject event is not signaled for a container itself, but for its parent device object (or generally, for an ancestor above it in the ACPI namespace), the container will be removed straight away without doing that whole dance. For this reason, modify acpi_bus_device_eject() to remove containers synchronously like any other objects (user space will get its uevent anyway in case it does some other things in response to it) and remove the eject_pending ACPI device flag that is not used any more. This way acpi_eject_store() doesn't have a reason to acquire acpi_scan_lock any more and one possible deadlock scenario goes away (plus the code is simplified a bit). Reported-and-tested-by: Gu Zheng <guz.fnst@cn.fujitsu.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Toshi Kani <toshi.kani@hp.com>
2013-08-28 13:41:07 -06:00
if (ACPI_SUCCESS(status))
return count;
ACPI / hotplug: Remove containers synchronously The current protocol for handling hot remove of containers is very fragile and causes acpi_eject_store() to acquire acpi_scan_lock which may deadlock with the removal of the device that it is called for (the reason is that device sysfs attributes cannot be removed while their callbacks are being executed and ACPI device objects are removed under acpi_scan_lock). The problem is related to the fact that containers are handled by acpi_bus_device_eject() in a special way, which is to emit an offline uevent instead of just removing the container. Then, user space is expected to handle that uevent and use the container's "eject" attribute to actually remove it. That is fragile, because user space may fail to complete the ejection (for example, by not using the container's "eject" attribute at all) leaving the BIOS kind of in a limbo. Moreover, if the eject event is not signaled for a container itself, but for its parent device object (or generally, for an ancestor above it in the ACPI namespace), the container will be removed straight away without doing that whole dance. For this reason, modify acpi_bus_device_eject() to remove containers synchronously like any other objects (user space will get its uevent anyway in case it does some other things in response to it) and remove the eject_pending ACPI device flag that is not used any more. This way acpi_eject_store() doesn't have a reason to acquire acpi_scan_lock any more and one possible deadlock scenario goes away (plus the code is simplified a bit). Reported-and-tested-by: Gu Zheng <guz.fnst@cn.fujitsu.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Toshi Kani <toshi.kani@hp.com>
2013-08-28 13:41:07 -06:00
put_device(&acpi_device->dev);
acpi_evaluate_ost(acpi_device->handle, ACPI_OST_EC_OSPM_EJECT,
ACPI_OST_SC_NON_SPECIFIC_FAILURE, NULL);
return status == AE_NO_MEMORY ? -ENOMEM : -EAGAIN;
}
static DEVICE_ATTR(eject, 0200, NULL, acpi_eject_store);
static ssize_t
acpi_device_hid_show(struct device *dev, struct device_attribute *attr, char *buf) {
struct acpi_device *acpi_dev = to_acpi_device(dev);
return sprintf(buf, "%s\n", acpi_device_hid(acpi_dev));
}
static DEVICE_ATTR(hid, 0444, acpi_device_hid_show, NULL);
static ssize_t acpi_device_uid_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct acpi_device *acpi_dev = to_acpi_device(dev);
return sprintf(buf, "%s\n", acpi_dev->pnp.unique_id);
}
static DEVICE_ATTR(uid, 0444, acpi_device_uid_show, NULL);
static ssize_t acpi_device_adr_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct acpi_device *acpi_dev = to_acpi_device(dev);
return sprintf(buf, "0x%08x\n",
(unsigned int)(acpi_dev->pnp.bus_address));
}
static DEVICE_ATTR(adr, 0444, acpi_device_adr_show, NULL);
static ssize_t
acpi_device_path_show(struct device *dev, struct device_attribute *attr, char *buf) {
struct acpi_device *acpi_dev = to_acpi_device(dev);
struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
int result;
result = acpi_get_name(acpi_dev->handle, ACPI_FULL_PATHNAME, &path);
if (result)
goto end;
result = sprintf(buf, "%s\n", (char*)path.pointer);
kfree(path.pointer);
end:
return result;
}
static DEVICE_ATTR(path, 0444, acpi_device_path_show, NULL);
ACPI: Add new sysfs interface to export device description Add support to export the device description obtained from the ACPI _STR method, if one exists for a device, to user-space via a sysfs interface. This new interface provides a standard and platform neutral way for users to obtain the description text stored in the ACPI _STR method. If no _STR method exists for the device, no sysfs 'description' file will be created. The 'description' file will be located in the /sys/devices/ directory using the device's path. /sys/device/<bus>/<bridge path>/<device path>.../firmware_node/description Example: /sys/devices/pci0000:00/0000:00.07.0/0000:0e:00.0/firmware_node/description It can also be located using the ACPI device path, for example: /sys/devices/LNXSYSTM:00/device:00/ACPI0004:00/PNP0A08:00/device:13/device:15/description /sys/devices/LNXSYSTM:00/device:00/ACPI0004:00/ACPI0004:01/ACPI0007:02/description Execute the 'cat' command on the 'description' file to obtain the description string for that device. This patch also includes documentation describing how the new sysfs interface works Changes from v1-v2 based on comments by Len Brown and Fengguang Wu * Removed output "No Description" and leaving a NULL attribute if the _STR method failed to evaluate. * In acpi_device_remove_files() removed the redundent check of dev->pnp.str_obj before calling free. This check triggered a message from smatch. Signed-off-by: Lance Ortiz <lance.ortiz@hp.com> Signed-off-by: Len Brown <len.brown@intel.com>
2012-10-02 12:43:23 -06:00
/* sysfs file that shows description text from the ACPI _STR method */
static ssize_t description_show(struct device *dev,
struct device_attribute *attr,
char *buf) {
struct acpi_device *acpi_dev = to_acpi_device(dev);
int result;
if (acpi_dev->pnp.str_obj == NULL)
return 0;
/*
* The _STR object contains a Unicode identifier for a device.
* We need to convert to utf-8 so it can be displayed.
*/
result = utf16s_to_utf8s(
(wchar_t *)acpi_dev->pnp.str_obj->buffer.pointer,
acpi_dev->pnp.str_obj->buffer.length,
UTF16_LITTLE_ENDIAN, buf,
PAGE_SIZE);
buf[result++] = '\n';
return result;
}
static DEVICE_ATTR(description, 0444, description_show, NULL);
static ssize_t
acpi_device_sun_show(struct device *dev, struct device_attribute *attr,
char *buf) {
struct acpi_device *acpi_dev = to_acpi_device(dev);
acpi_status status;
unsigned long long sun;
status = acpi_evaluate_integer(acpi_dev->handle, "_SUN", NULL, &sun);
if (ACPI_FAILURE(status))
return -ENODEV;
return sprintf(buf, "%llu\n", sun);
}
static DEVICE_ATTR(sun, 0444, acpi_device_sun_show, NULL);
static ssize_t status_show(struct device *dev, struct device_attribute *attr,
char *buf) {
struct acpi_device *acpi_dev = to_acpi_device(dev);
acpi_status status;
unsigned long long sta;
status = acpi_evaluate_integer(acpi_dev->handle, "_STA", NULL, &sta);
if (ACPI_FAILURE(status))
return -ENODEV;
return sprintf(buf, "%llu\n", sta);
}
static DEVICE_ATTR_RO(status);
static int acpi_device_setup_files(struct acpi_device *dev)
{
ACPI: Add new sysfs interface to export device description Add support to export the device description obtained from the ACPI _STR method, if one exists for a device, to user-space via a sysfs interface. This new interface provides a standard and platform neutral way for users to obtain the description text stored in the ACPI _STR method. If no _STR method exists for the device, no sysfs 'description' file will be created. The 'description' file will be located in the /sys/devices/ directory using the device's path. /sys/device/<bus>/<bridge path>/<device path>.../firmware_node/description Example: /sys/devices/pci0000:00/0000:00.07.0/0000:0e:00.0/firmware_node/description It can also be located using the ACPI device path, for example: /sys/devices/LNXSYSTM:00/device:00/ACPI0004:00/PNP0A08:00/device:13/device:15/description /sys/devices/LNXSYSTM:00/device:00/ACPI0004:00/ACPI0004:01/ACPI0007:02/description Execute the 'cat' command on the 'description' file to obtain the description string for that device. This patch also includes documentation describing how the new sysfs interface works Changes from v1-v2 based on comments by Len Brown and Fengguang Wu * Removed output "No Description" and leaving a NULL attribute if the _STR method failed to evaluate. * In acpi_device_remove_files() removed the redundent check of dev->pnp.str_obj before calling free. This check triggered a message from smatch. Signed-off-by: Lance Ortiz <lance.ortiz@hp.com> Signed-off-by: Len Brown <len.brown@intel.com>
2012-10-02 12:43:23 -06:00
struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
acpi_status status;
int result = 0;
/*
* Devices gotten from FADT don't have a "path" attribute
*/
if (dev->handle) {
result = device_create_file(&dev->dev, &dev_attr_path);
if (result)
goto end;
}
if (!list_empty(&dev->pnp.ids)) {
result = device_create_file(&dev->dev, &dev_attr_hid);
if (result)
goto end;
result = device_create_file(&dev->dev, &dev_attr_modalias);
if (result)
goto end;
}
ACPI: Add new sysfs interface to export device description Add support to export the device description obtained from the ACPI _STR method, if one exists for a device, to user-space via a sysfs interface. This new interface provides a standard and platform neutral way for users to obtain the description text stored in the ACPI _STR method. If no _STR method exists for the device, no sysfs 'description' file will be created. The 'description' file will be located in the /sys/devices/ directory using the device's path. /sys/device/<bus>/<bridge path>/<device path>.../firmware_node/description Example: /sys/devices/pci0000:00/0000:00.07.0/0000:0e:00.0/firmware_node/description It can also be located using the ACPI device path, for example: /sys/devices/LNXSYSTM:00/device:00/ACPI0004:00/PNP0A08:00/device:13/device:15/description /sys/devices/LNXSYSTM:00/device:00/ACPI0004:00/ACPI0004:01/ACPI0007:02/description Execute the 'cat' command on the 'description' file to obtain the description string for that device. This patch also includes documentation describing how the new sysfs interface works Changes from v1-v2 based on comments by Len Brown and Fengguang Wu * Removed output "No Description" and leaving a NULL attribute if the _STR method failed to evaluate. * In acpi_device_remove_files() removed the redundent check of dev->pnp.str_obj before calling free. This check triggered a message from smatch. Signed-off-by: Lance Ortiz <lance.ortiz@hp.com> Signed-off-by: Len Brown <len.brown@intel.com>
2012-10-02 12:43:23 -06:00
/*
* If device has _STR, 'description' file is created
*/
if (acpi_has_method(dev->handle, "_STR")) {
ACPI: Add new sysfs interface to export device description Add support to export the device description obtained from the ACPI _STR method, if one exists for a device, to user-space via a sysfs interface. This new interface provides a standard and platform neutral way for users to obtain the description text stored in the ACPI _STR method. If no _STR method exists for the device, no sysfs 'description' file will be created. The 'description' file will be located in the /sys/devices/ directory using the device's path. /sys/device/<bus>/<bridge path>/<device path>.../firmware_node/description Example: /sys/devices/pci0000:00/0000:00.07.0/0000:0e:00.0/firmware_node/description It can also be located using the ACPI device path, for example: /sys/devices/LNXSYSTM:00/device:00/ACPI0004:00/PNP0A08:00/device:13/device:15/description /sys/devices/LNXSYSTM:00/device:00/ACPI0004:00/ACPI0004:01/ACPI0007:02/description Execute the 'cat' command on the 'description' file to obtain the description string for that device. This patch also includes documentation describing how the new sysfs interface works Changes from v1-v2 based on comments by Len Brown and Fengguang Wu * Removed output "No Description" and leaving a NULL attribute if the _STR method failed to evaluate. * In acpi_device_remove_files() removed the redundent check of dev->pnp.str_obj before calling free. This check triggered a message from smatch. Signed-off-by: Lance Ortiz <lance.ortiz@hp.com> Signed-off-by: Len Brown <len.brown@intel.com>
2012-10-02 12:43:23 -06:00
status = acpi_evaluate_object(dev->handle, "_STR",
NULL, &buffer);
if (ACPI_FAILURE(status))
buffer.pointer = NULL;
dev->pnp.str_obj = buffer.pointer;
result = device_create_file(&dev->dev, &dev_attr_description);
if (result)
goto end;
}
if (dev->pnp.type.bus_address)
result = device_create_file(&dev->dev, &dev_attr_adr);
if (dev->pnp.unique_id)
result = device_create_file(&dev->dev, &dev_attr_uid);
if (acpi_has_method(dev->handle, "_SUN")) {
result = device_create_file(&dev->dev, &dev_attr_sun);
if (result)
goto end;
}
if (acpi_has_method(dev->handle, "_STA")) {
result = device_create_file(&dev->dev, &dev_attr_status);
if (result)
goto end;
}
/*
* If device has _EJ0, 'eject' file is created that is used to trigger
* hot-removal function from userland.
*/
if (acpi_has_method(dev->handle, "_EJ0")) {
result = device_create_file(&dev->dev, &dev_attr_eject);
if (result)
return result;
}
if (dev->flags.power_manageable) {
result = device_create_file(&dev->dev, &dev_attr_power_state);
if (result)
return result;
if (dev->power.flags.power_resources)
result = device_create_file(&dev->dev,
&dev_attr_real_power_state);
}
end:
return result;
}
static void acpi_device_remove_files(struct acpi_device *dev)
{
if (dev->flags.power_manageable) {
device_remove_file(&dev->dev, &dev_attr_power_state);
if (dev->power.flags.power_resources)
device_remove_file(&dev->dev,
&dev_attr_real_power_state);
}
/*
ACPI: Add new sysfs interface to export device description Add support to export the device description obtained from the ACPI _STR method, if one exists for a device, to user-space via a sysfs interface. This new interface provides a standard and platform neutral way for users to obtain the description text stored in the ACPI _STR method. If no _STR method exists for the device, no sysfs 'description' file will be created. The 'description' file will be located in the /sys/devices/ directory using the device's path. /sys/device/<bus>/<bridge path>/<device path>.../firmware_node/description Example: /sys/devices/pci0000:00/0000:00.07.0/0000:0e:00.0/firmware_node/description It can also be located using the ACPI device path, for example: /sys/devices/LNXSYSTM:00/device:00/ACPI0004:00/PNP0A08:00/device:13/device:15/description /sys/devices/LNXSYSTM:00/device:00/ACPI0004:00/ACPI0004:01/ACPI0007:02/description Execute the 'cat' command on the 'description' file to obtain the description string for that device. This patch also includes documentation describing how the new sysfs interface works Changes from v1-v2 based on comments by Len Brown and Fengguang Wu * Removed output "No Description" and leaving a NULL attribute if the _STR method failed to evaluate. * In acpi_device_remove_files() removed the redundent check of dev->pnp.str_obj before calling free. This check triggered a message from smatch. Signed-off-by: Lance Ortiz <lance.ortiz@hp.com> Signed-off-by: Len Brown <len.brown@intel.com>
2012-10-02 12:43:23 -06:00
* If device has _STR, remove 'description' file
*/
if (acpi_has_method(dev->handle, "_STR")) {
ACPI: Add new sysfs interface to export device description Add support to export the device description obtained from the ACPI _STR method, if one exists for a device, to user-space via a sysfs interface. This new interface provides a standard and platform neutral way for users to obtain the description text stored in the ACPI _STR method. If no _STR method exists for the device, no sysfs 'description' file will be created. The 'description' file will be located in the /sys/devices/ directory using the device's path. /sys/device/<bus>/<bridge path>/<device path>.../firmware_node/description Example: /sys/devices/pci0000:00/0000:00.07.0/0000:0e:00.0/firmware_node/description It can also be located using the ACPI device path, for example: /sys/devices/LNXSYSTM:00/device:00/ACPI0004:00/PNP0A08:00/device:13/device:15/description /sys/devices/LNXSYSTM:00/device:00/ACPI0004:00/ACPI0004:01/ACPI0007:02/description Execute the 'cat' command on the 'description' file to obtain the description string for that device. This patch also includes documentation describing how the new sysfs interface works Changes from v1-v2 based on comments by Len Brown and Fengguang Wu * Removed output "No Description" and leaving a NULL attribute if the _STR method failed to evaluate. * In acpi_device_remove_files() removed the redundent check of dev->pnp.str_obj before calling free. This check triggered a message from smatch. Signed-off-by: Lance Ortiz <lance.ortiz@hp.com> Signed-off-by: Len Brown <len.brown@intel.com>
2012-10-02 12:43:23 -06:00
kfree(dev->pnp.str_obj);
device_remove_file(&dev->dev, &dev_attr_description);
}
/*
* If device has _EJ0, remove 'eject' file.
*/
if (acpi_has_method(dev->handle, "_EJ0"))
device_remove_file(&dev->dev, &dev_attr_eject);
if (acpi_has_method(dev->handle, "_SUN"))
device_remove_file(&dev->dev, &dev_attr_sun);
if (dev->pnp.unique_id)
device_remove_file(&dev->dev, &dev_attr_uid);
if (dev->pnp.type.bus_address)
device_remove_file(&dev->dev, &dev_attr_adr);
device_remove_file(&dev->dev, &dev_attr_modalias);
device_remove_file(&dev->dev, &dev_attr_hid);
if (acpi_has_method(dev->handle, "_STA"))
device_remove_file(&dev->dev, &dev_attr_status);
if (dev->handle)
device_remove_file(&dev->dev, &dev_attr_path);
}
/* --------------------------------------------------------------------------
ACPI Bus operations
-------------------------------------------------------------------------- */
static const struct acpi_device_id *__acpi_match_device(
struct acpi_device *device, const struct acpi_device_id *ids)
{
const struct acpi_device_id *id;
struct acpi_hardware_id *hwid;
/*
* If the device is not present, it is unnecessary to load device
* driver for it.
*/
if (!device->status.present)
return NULL;
for (id = ids; id->id[0]; id++)
list_for_each_entry(hwid, &device->pnp.ids, list)
if (!strcmp((char *) id->id, hwid->id))
return id;
return NULL;
}
/**
* acpi_match_device - Match a struct device against a given list of ACPI IDs
* @ids: Array of struct acpi_device_id object to match against.
* @dev: The device structure to match.
*
* Check if @dev has a valid ACPI handle and if there is a struct acpi_device
* object for that handle and use that object to match against a given list of
* device IDs.
*
* Return a pointer to the first matching ID on success or %NULL on failure.
*/
const struct acpi_device_id *acpi_match_device(const struct acpi_device_id *ids,
const struct device *dev)
{
struct acpi_device *adev;
acpi_handle handle = ACPI_HANDLE(dev);
if (!ids || !handle || acpi_bus_get_device(handle, &adev))
return NULL;
ACPI: Use ACPI companion to match only the first physical device Commit 6ab3430129e2 ("mfd: Add ACPI support") made the MFD subdevices share the parent MFD ACPI companion if no _HID/_CID is specified for the subdevice in mfd_cell description. However, since all the subdevices share the ACPI companion, the match and modalias generation logic started to use the ACPI companion as well resulting this: # cat /sys/bus/platform/devices/HID-SENSOR-200041.6.auto/modalias acpi:INT33D1:PNP0C50: instead of the expected one # cat /sys/bus/platform/devices/HID-SENSOR-200041.6.auto/modalias platform:HID-SENSOR-200041 In other words the subdevice modalias is overwritten by the one taken from ACPI companion. This causes udev not to load the driver anymore. It is useful to be able to share the ACPI companion so that MFD subdevices (and possibly other devices as well) can access the ACPI resources even if they do not have ACPI representation in the namespace themselves. An example where this is used is Minnowboard LPC driver that creates GPIO as a subdevice among other things. Without the ACPI companion gpiolib is not able to lookup the corresponding GPIO controller from ACPI GpioIo resource. To fix this, restrict the match and modalias logic to be limited to the first (primary) physical device associated with the given ACPI comapnion. The secondary devices will still be able to access the ACPI companion, but they will be matched in a different way. Fixes: 6ab3430129e2 (mfd: Add ACPI support) Reported-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-10-24 08:40:54 -06:00
if (!acpi_companion_match(dev))
return NULL;
return __acpi_match_device(adev, ids);
}
EXPORT_SYMBOL_GPL(acpi_match_device);
int acpi_match_device_ids(struct acpi_device *device,
const struct acpi_device_id *ids)
{
return __acpi_match_device(device, ids) ? 0 : -ENOENT;
}
EXPORT_SYMBOL(acpi_match_device_ids);
static void acpi_free_power_resources_lists(struct acpi_device *device)
{
int i;
if (device->wakeup.flags.valid)
acpi_power_resources_list_free(&device->wakeup.resources);
if (!device->flags.power_manageable)
return;
for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
struct acpi_device_power_state *ps = &device->power.states[i];
acpi_power_resources_list_free(&ps->resources);
}
}
static void acpi_device_release(struct device *dev)
{
struct acpi_device *acpi_dev = to_acpi_device(dev);
acpi_free_pnp_ids(&acpi_dev->pnp);
acpi_free_power_resources_lists(acpi_dev);
kfree(acpi_dev);
}
static int acpi_bus_match(struct device *dev, struct device_driver *drv)
{
struct acpi_device *acpi_dev = to_acpi_device(dev);
struct acpi_driver *acpi_drv = to_acpi_driver(drv);
return acpi_dev->flags.match_driver
ACPI: Separate adding ACPI device objects from probing ACPI drivers Split the ACPI namespace scanning for devices into two passes, such that struct acpi_device objects are registerd in the first pass without probing ACPI drivers and the drivers are probed against them directly in the second pass. There are two main reasons for doing that. First, the ACPI PCI root bridge driver's .add() routine, acpi_pci_root_add(), causes struct pci_dev objects to be created for all PCI devices under the given root bridge. Usually, there are corresponding ACPI device nodes in the ACPI namespace for some of those devices and therefore there should be "companion" struct acpi_device objects to attach those struct pci_dev objects to. These struct acpi_device objects should exist when the corresponding struct pci_dev objects are created, but that is only guaranteed during boot and not during hotplug. This leads to a number of functional differences between the boot and the hotplug cases which are not strictly necessary and make the code more complicated. For example, this forces the ACPI PCI root bridge driver to defer the registration of the just created struct pci_dev objects and to use a special .start() callback routine, acpi_pci_root_start(), to make sure that all of the "companion" struct acpi_device objects will be present at PCI devices registration time during hotplug. If those differences can be eliminated, we will be able to consolidate the boot and hotplug code paths for the enumeration and registration of PCI devices and to reduce the complexity of that code quite a bit. The second reason is that, in general, it should be possible to resolve conflicts of resources assigned by the BIOS to different devices represented by ACPI namespace nodes before any drivers bind to them and before they are attached to "companion" objects representing physical devices (such as struct pci_dev). However, for this purpose we first need to enumerate all ACPI device nodes in the given namespace scope. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Yinghai Lu <yinghai@kernel.org> Acked-by: Toshi Kani <toshi.kani@hp.com>
2012-12-20 16:36:39 -07:00
&& !acpi_match_device_ids(acpi_dev, acpi_drv->ids);
}
static int acpi_device_uevent(struct device *dev, struct kobj_uevent_env *env)
{
struct acpi_device *acpi_dev = to_acpi_device(dev);
int len;
if (list_empty(&acpi_dev->pnp.ids))
return 0;
if (add_uevent_var(env, "MODALIAS="))
return -ENOMEM;
len = create_modalias(acpi_dev, &env->buf[env->buflen - 1],
sizeof(env->buf) - env->buflen);
if (len <= 0)
return len;
env->buflen += len;
return 0;
}
static void acpi_device_notify(acpi_handle handle, u32 event, void *data)
{
struct acpi_device *device = data;
device->driver->ops.notify(device, event);
}
static void acpi_device_notify_fixed(void *data)
{
struct acpi_device *device = data;
/* Fixed hardware devices have no handles */
acpi_device_notify(NULL, ACPI_FIXED_HARDWARE_EVENT, device);
}
static acpi_status acpi_device_fixed_event(void *data)
{
acpi_os_execute(OSL_NOTIFY_HANDLER, acpi_device_notify_fixed, data);
return AE_OK;
}
static int acpi_device_install_notify_handler(struct acpi_device *device)
{
acpi_status status;
if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
status =
acpi_install_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
acpi_device_fixed_event,
device);
else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
status =
acpi_install_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
acpi_device_fixed_event,
device);
else
status = acpi_install_notify_handler(device->handle,
ACPI_DEVICE_NOTIFY,
acpi_device_notify,
device);
if (ACPI_FAILURE(status))
return -EINVAL;
return 0;
}
static void acpi_device_remove_notify_handler(struct acpi_device *device)
{
if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
acpi_remove_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
acpi_device_fixed_event);
else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
acpi_remove_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
acpi_device_fixed_event);
else
acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
acpi_device_notify);
}
static int acpi_device_probe(struct device *dev)
{
struct acpi_device *acpi_dev = to_acpi_device(dev);
struct acpi_driver *acpi_drv = to_acpi_driver(dev->driver);
int ret;
if (acpi_dev->handler && !acpi_is_pnp_device(acpi_dev))
return -EINVAL;
if (!acpi_drv->ops.add)
return -ENOSYS;
ret = acpi_drv->ops.add(acpi_dev);
if (ret)
return ret;
acpi_dev->driver = acpi_drv;
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
"Driver [%s] successfully bound to device [%s]\n",
acpi_drv->name, acpi_dev->pnp.bus_id));
if (acpi_drv->ops.notify) {
ret = acpi_device_install_notify_handler(acpi_dev);
if (ret) {
if (acpi_drv->ops.remove)
acpi_drv->ops.remove(acpi_dev);
acpi_dev->driver = NULL;
acpi_dev->driver_data = NULL;
return ret;
}
}
ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found driver [%s] for device [%s]\n",
acpi_drv->name, acpi_dev->pnp.bus_id));
get_device(dev);
return 0;
}
static int acpi_device_remove(struct device * dev)
{
struct acpi_device *acpi_dev = to_acpi_device(dev);
struct acpi_driver *acpi_drv = acpi_dev->driver;
if (acpi_drv) {
if (acpi_drv->ops.notify)
acpi_device_remove_notify_handler(acpi_dev);
if (acpi_drv->ops.remove)
acpi_drv->ops.remove(acpi_dev);
}
acpi_dev->driver = NULL;
acpi_dev->driver_data = NULL;
put_device(dev);
return 0;
}
struct bus_type acpi_bus_type = {
.name = "acpi",
.match = acpi_bus_match,
.probe = acpi_device_probe,
.remove = acpi_device_remove,
.uevent = acpi_device_uevent,
};
static void acpi_device_del(struct acpi_device *device)
{
mutex_lock(&acpi_device_lock);
if (device->parent)
list_del(&device->node);
list_del(&device->wakeup_list);
mutex_unlock(&acpi_device_lock);
acpi_power_add_remove_device(device, false);
acpi_device_remove_files(device);
if (device->remove)
device->remove(device);
device_del(&device->dev);
}
static LIST_HEAD(acpi_device_del_list);
static DEFINE_MUTEX(acpi_device_del_lock);
static void acpi_device_del_work_fn(struct work_struct *work_not_used)
{
for (;;) {
struct acpi_device *adev;
mutex_lock(&acpi_device_del_lock);
if (list_empty(&acpi_device_del_list)) {
mutex_unlock(&acpi_device_del_lock);
break;
}
adev = list_first_entry(&acpi_device_del_list,
struct acpi_device, del_list);
list_del(&adev->del_list);
mutex_unlock(&acpi_device_del_lock);
acpi_device_del(adev);
/*
* Drop references to all power resources that might have been
* used by the device.
*/
acpi_power_transition(adev, ACPI_STATE_D3_COLD);
put_device(&adev->dev);
}
}
/**
* acpi_scan_drop_device - Drop an ACPI device object.
* @handle: Handle of an ACPI namespace node, not used.
* @context: Address of the ACPI device object to drop.
*
* This is invoked by acpi_ns_delete_node() during the removal of the ACPI
* namespace node the device object pointed to by @context is attached to.
*
* The unregistration is carried out asynchronously to avoid running
* acpi_device_del() under the ACPICA's namespace mutex and the list is used to
* ensure the correct ordering (the device objects must be unregistered in the
* same order in which the corresponding namespace nodes are deleted).
*/
static void acpi_scan_drop_device(acpi_handle handle, void *context)
{
static DECLARE_WORK(work, acpi_device_del_work_fn);
struct acpi_device *adev = context;
mutex_lock(&acpi_device_del_lock);
/*
* Use the ACPI hotplug workqueue which is ordered, so this work item
* won't run after any hotplug work items submitted subsequently. That
* prevents attempts to register device objects identical to those being
* deleted from happening concurrently (such attempts result from
* hotplug events handled via the ACPI hotplug workqueue). It also will
* run after all of the work items submitted previosuly, which helps
* those work items to ensure that they are not accessing stale device
* objects.
*/
if (list_empty(&acpi_device_del_list))
acpi_queue_hotplug_work(&work);
list_add_tail(&adev->del_list, &acpi_device_del_list);
/* Make acpi_ns_validate_handle() return NULL for this handle. */
adev->handle = INVALID_ACPI_HANDLE;
mutex_unlock(&acpi_device_del_lock);
}
ACPI / hotplug: Fix potential race in acpi_bus_notify() There is a slight possibility for the ACPI device object pointed to by adev in acpi_hotplug_notify_cb() to become invalid between the acpi_bus_get_device() that it comes from and the subsequent dereference of that pointer under get_device(). Namely, if acpi_scan_drop_device() runs in parallel with acpi_hotplug_notify_cb(), acpi_device_del_work_fn() queued up by it may delete the device object in question right after a successful execution of acpi_bus_get_device() in acpi_bus_notify(). An analogous problem is present in acpi_bus_notify() where the device pointer coming from acpi_bus_get_device() may become invalid before it subsequent dereference in the "if" block. To prevent that from happening, introduce a new function, acpi_bus_get_acpi_device(), working analogously to acpi_bus_get_device() except that it will grab a reference to the ACPI device object returned by it and it will do that under the ACPICA's namespace mutex. Then, make both acpi_hotplug_notify_cb() and acpi_bus_notify() use acpi_bus_get_acpi_device() instead of acpi_bus_get_device() so as to ensure that the pointers used by them will not become stale at one point. In addition to that, introduce acpi_bus_put_acpi_device() as a wrapper around put_device() to be used along with acpi_bus_get_acpi_device() and make the (new) users of the latter use acpi_bus_put_acpi_device() too. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2014-02-03 16:43:05 -07:00
static int acpi_get_device_data(acpi_handle handle, struct acpi_device **device,
void (*callback)(void *))
{
acpi_status status;
if (!device)
return -EINVAL;
ACPI / hotplug: Fix potential race in acpi_bus_notify() There is a slight possibility for the ACPI device object pointed to by adev in acpi_hotplug_notify_cb() to become invalid between the acpi_bus_get_device() that it comes from and the subsequent dereference of that pointer under get_device(). Namely, if acpi_scan_drop_device() runs in parallel with acpi_hotplug_notify_cb(), acpi_device_del_work_fn() queued up by it may delete the device object in question right after a successful execution of acpi_bus_get_device() in acpi_bus_notify(). An analogous problem is present in acpi_bus_notify() where the device pointer coming from acpi_bus_get_device() may become invalid before it subsequent dereference in the "if" block. To prevent that from happening, introduce a new function, acpi_bus_get_acpi_device(), working analogously to acpi_bus_get_device() except that it will grab a reference to the ACPI device object returned by it and it will do that under the ACPICA's namespace mutex. Then, make both acpi_hotplug_notify_cb() and acpi_bus_notify() use acpi_bus_get_acpi_device() instead of acpi_bus_get_device() so as to ensure that the pointers used by them will not become stale at one point. In addition to that, introduce acpi_bus_put_acpi_device() as a wrapper around put_device() to be used along with acpi_bus_get_acpi_device() and make the (new) users of the latter use acpi_bus_put_acpi_device() too. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2014-02-03 16:43:05 -07:00
status = acpi_get_data_full(handle, acpi_scan_drop_device,
(void **)device, callback);
if (ACPI_FAILURE(status) || !*device) {
ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No context for object [%p]\n",
handle));
return -ENODEV;
}
return 0;
}
ACPI / hotplug: Fix potential race in acpi_bus_notify() There is a slight possibility for the ACPI device object pointed to by adev in acpi_hotplug_notify_cb() to become invalid between the acpi_bus_get_device() that it comes from and the subsequent dereference of that pointer under get_device(). Namely, if acpi_scan_drop_device() runs in parallel with acpi_hotplug_notify_cb(), acpi_device_del_work_fn() queued up by it may delete the device object in question right after a successful execution of acpi_bus_get_device() in acpi_bus_notify(). An analogous problem is present in acpi_bus_notify() where the device pointer coming from acpi_bus_get_device() may become invalid before it subsequent dereference in the "if" block. To prevent that from happening, introduce a new function, acpi_bus_get_acpi_device(), working analogously to acpi_bus_get_device() except that it will grab a reference to the ACPI device object returned by it and it will do that under the ACPICA's namespace mutex. Then, make both acpi_hotplug_notify_cb() and acpi_bus_notify() use acpi_bus_get_acpi_device() instead of acpi_bus_get_device() so as to ensure that the pointers used by them will not become stale at one point. In addition to that, introduce acpi_bus_put_acpi_device() as a wrapper around put_device() to be used along with acpi_bus_get_acpi_device() and make the (new) users of the latter use acpi_bus_put_acpi_device() too. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2014-02-03 16:43:05 -07:00
int acpi_bus_get_device(acpi_handle handle, struct acpi_device **device)
{
return acpi_get_device_data(handle, device, NULL);
}
EXPORT_SYMBOL(acpi_bus_get_device);
ACPI / hotplug: Fix potential race in acpi_bus_notify() There is a slight possibility for the ACPI device object pointed to by adev in acpi_hotplug_notify_cb() to become invalid between the acpi_bus_get_device() that it comes from and the subsequent dereference of that pointer under get_device(). Namely, if acpi_scan_drop_device() runs in parallel with acpi_hotplug_notify_cb(), acpi_device_del_work_fn() queued up by it may delete the device object in question right after a successful execution of acpi_bus_get_device() in acpi_bus_notify(). An analogous problem is present in acpi_bus_notify() where the device pointer coming from acpi_bus_get_device() may become invalid before it subsequent dereference in the "if" block. To prevent that from happening, introduce a new function, acpi_bus_get_acpi_device(), working analogously to acpi_bus_get_device() except that it will grab a reference to the ACPI device object returned by it and it will do that under the ACPICA's namespace mutex. Then, make both acpi_hotplug_notify_cb() and acpi_bus_notify() use acpi_bus_get_acpi_device() instead of acpi_bus_get_device() so as to ensure that the pointers used by them will not become stale at one point. In addition to that, introduce acpi_bus_put_acpi_device() as a wrapper around put_device() to be used along with acpi_bus_get_acpi_device() and make the (new) users of the latter use acpi_bus_put_acpi_device() too. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2014-02-03 16:43:05 -07:00
static void get_acpi_device(void *dev)
{
if (dev)
get_device(&((struct acpi_device *)dev)->dev);
}
struct acpi_device *acpi_bus_get_acpi_device(acpi_handle handle)
{
struct acpi_device *adev = NULL;
acpi_get_device_data(handle, &adev, get_acpi_device);
return adev;
}
void acpi_bus_put_acpi_device(struct acpi_device *adev)
{
put_device(&adev->dev);
}
int acpi_device_add(struct acpi_device *device,
void (*release)(struct device *))
{
int result;
struct acpi_device_bus_id *acpi_device_bus_id, *new_bus_id;
int found = 0;
if (device->handle) {
acpi_status status;
status = acpi_attach_data(device->handle, acpi_scan_drop_device,
device);
if (ACPI_FAILURE(status)) {
acpi_handle_err(device->handle,
"Unable to attach device data\n");
return -ENODEV;
}
}
/*
* Linkage
* -------
* Link this device to its parent and siblings.
*/
INIT_LIST_HEAD(&device->children);
INIT_LIST_HEAD(&device->node);
INIT_LIST_HEAD(&device->wakeup_list);
INIT_LIST_HEAD(&device->physical_node_list);
INIT_LIST_HEAD(&device->del_list);
mutex_init(&device->physical_node_lock);
new_bus_id = kzalloc(sizeof(struct acpi_device_bus_id), GFP_KERNEL);
if (!new_bus_id) {
pr_err(PREFIX "Memory allocation error\n");
result = -ENOMEM;
goto err_detach;
}
mutex_lock(&acpi_device_lock);
/*
* Find suitable bus_id and instance number in acpi_bus_id_list
* If failed, create one and link it into acpi_bus_id_list
*/
list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
if (!strcmp(acpi_device_bus_id->bus_id,
acpi_device_hid(device))) {
acpi_device_bus_id->instance_no++;
found = 1;
kfree(new_bus_id);
break;
}
}
if (!found) {
acpi_device_bus_id = new_bus_id;
strcpy(acpi_device_bus_id->bus_id, acpi_device_hid(device));
acpi_device_bus_id->instance_no = 0;
list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
}
dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, acpi_device_bus_id->instance_no);
if (device->parent)
list_add_tail(&device->node, &device->parent->children);
if (device->wakeup.flags.valid)
list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
mutex_unlock(&acpi_device_lock);
if (device->parent)
device->dev.parent = &device->parent->dev;
device->dev.bus = &acpi_bus_type;
device->dev.release = release;
result = device_add(&device->dev);
if (result) {
dev_err(&device->dev, "Error registering device\n");
goto err;
}
result = acpi_device_setup_files(device);
if (result)
printk(KERN_ERR PREFIX "Error creating sysfs interface for device %s\n",
dev_name(&device->dev));
return 0;
err:
mutex_lock(&acpi_device_lock);
if (device->parent)
list_del(&device->node);
list_del(&device->wakeup_list);
mutex_unlock(&acpi_device_lock);
err_detach:
acpi_detach_data(device->handle, acpi_scan_drop_device);
return result;
}
/* --------------------------------------------------------------------------
Driver Management
-------------------------------------------------------------------------- */
/**
* acpi_bus_register_driver - register a driver with the ACPI bus
* @driver: driver being registered
*
* Registers a driver with the ACPI bus. Searches the namespace for all
* devices that match the driver's criteria and binds. Returns zero for
* success or a negative error status for failure.
*/
int acpi_bus_register_driver(struct acpi_driver *driver)
{
int ret;
if (acpi_disabled)
return -ENODEV;
driver->drv.name = driver->name;
driver->drv.bus = &acpi_bus_type;
driver->drv.owner = driver->owner;
ret = driver_register(&driver->drv);
return ret;
}
EXPORT_SYMBOL(acpi_bus_register_driver);
/**
* acpi_bus_unregister_driver - unregisters a driver with the ACPI bus
* @driver: driver to unregister
*
* Unregisters a driver with the ACPI bus. Searches the namespace for all
* devices that match the driver's criteria and unbinds.
*/
void acpi_bus_unregister_driver(struct acpi_driver *driver)
{
driver_unregister(&driver->drv);
}
EXPORT_SYMBOL(acpi_bus_unregister_driver);
/* --------------------------------------------------------------------------
Device Enumeration
-------------------------------------------------------------------------- */
static struct acpi_device *acpi_bus_get_parent(acpi_handle handle)
{
struct acpi_device *device = NULL;
acpi_status status;
/*
* Fixed hardware devices do not appear in the namespace and do not
* have handles, but we fabricate acpi_devices for them, so we have
* to deal with them specially.
*/
if (!handle)
return acpi_root;
do {
status = acpi_get_parent(handle, &handle);
if (ACPI_FAILURE(status))
return status == AE_NULL_ENTRY ? NULL : acpi_root;
} while (acpi_bus_get_device(handle, &device));
return device;
}
acpi_status
acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
{
acpi_status status;
acpi_handle tmp;
struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
union acpi_object *obj;
status = acpi_get_handle(handle, "_EJD", &tmp);
if (ACPI_FAILURE(status))
return status;
status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
if (ACPI_SUCCESS(status)) {
obj = buffer.pointer;
status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
ejd);
kfree(buffer.pointer);
}
return status;
}
EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
static int acpi_bus_extract_wakeup_device_power_package(acpi_handle handle,
struct acpi_device_wakeup *wakeup)
{
struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
union acpi_object *package = NULL;
union acpi_object *element = NULL;
acpi_status status;
int err = -ENODATA;
if (!wakeup)
return -EINVAL;
INIT_LIST_HEAD(&wakeup->resources);
/* _PRW */
status = acpi_evaluate_object(handle, "_PRW", NULL, &buffer);
if (ACPI_FAILURE(status)) {
ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
return err;
}
package = (union acpi_object *)buffer.pointer;
if (!package || package->package.count < 2)
goto out;
element = &(package->package.elements[0]);
if (!element)
goto out;
if (element->type == ACPI_TYPE_PACKAGE) {
if ((element->package.count < 2) ||
(element->package.elements[0].type !=
ACPI_TYPE_LOCAL_REFERENCE)
|| (element->package.elements[1].type != ACPI_TYPE_INTEGER))
goto out;
wakeup->gpe_device =
element->package.elements[0].reference.handle;
wakeup->gpe_number =
(u32) element->package.elements[1].integer.value;
} else if (element->type == ACPI_TYPE_INTEGER) {
wakeup->gpe_device = NULL;
wakeup->gpe_number = element->integer.value;
} else {
goto out;
}
element = &(package->package.elements[1]);
if (element->type != ACPI_TYPE_INTEGER)
goto out;
wakeup->sleep_state = element->integer.value;
err = acpi_extract_power_resources(package, 2, &wakeup->resources);
if (err)
goto out;
if (!list_empty(&wakeup->resources)) {
int sleep_state;
ACPI / PM: Take unusual configurations of power resources into account Commit d2e5f0c (ACPI / PCI: Rework the setup and cleanup of device wakeup) moved the initial disabling of system wakeup for PCI devices into a place where it can actually work and that exposed a hidden old issue with crap^Wunusual system designs where the same power resources are used for both wakeup power and device power control at run time. Namely, say there is one power resource such that the ACPI power state D0 of a PCI device depends on that power resource (i.e. the device is in D0 when that power resource is "on") and it is used as a wakeup power resource for the same device. Then, calling acpi_pci_sleep_wake(pci_dev, false) for the device in question will cause the reference counter of that power resource to drop to 0, which in turn will cause it to be turned off. As a result, the device will go into D3cold at that point, although it should have stayed in D0. As it turns out, that happens to USB controllers on some laptops and USB becomes unusable on those machines as a result, which is a major regression from v3.8. To fix this problem, (1) increment the reference counters of wakup power resources during their initialization if they are "on" initially, (2) prevent acpi_disable_wakeup_device_power() from decrementing the reference counters of wakeup power resources that were not enabled for wakeup power previously, and (3) prevent acpi_enable_wakeup_device_power() from incrementing the reference counters of wakeup power resources that already are enabled for wakeup power. In addition to that, if it is impossible to determine the initial states of wakeup power resources, avoid enabling wakeup for devices whose wakeup power depends on those power resources. Reported-by: Dave Jones <davej@redhat.com> Reported-by: Fabio Baltieri <fabio.baltieri@linaro.org> Tested-by: Fabio Baltieri <fabio.baltieri@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-02-23 15:15:21 -07:00
err = acpi_power_wakeup_list_init(&wakeup->resources,
&sleep_state);
if (err) {
acpi_handle_warn(handle, "Retrieving current states "
"of wakeup power resources failed\n");
acpi_power_resources_list_free(&wakeup->resources);
goto out;
}
if (sleep_state < wakeup->sleep_state) {
acpi_handle_warn(handle, "Overriding _PRW sleep state "
"(S%d) by S%d from power resources\n",
(int)wakeup->sleep_state, sleep_state);
wakeup->sleep_state = sleep_state;
}
}
ACPI / ACPICA: Do not execute _PRW methods during initialization Currently, during initialization ACPICA walks the entire ACPI namespace in search of any device objects with assciated _PRW methods. All of the _PRW methods found are executed in the process to extract the GPE information returned by them, so that the GPEs in question can be marked as "able to wakeup" (more precisely, the ACPI_GPE_CAN_WAKE flag is set for them). The only purpose of this exercise is to avoid enabling the CAN_WAKE GPEs automatically, even if there are _Lxx/_Exx methods associated with them. However, it is both costly and unnecessary, because the host OS has to execute the _PRW methods anyway to check which devices can wake up the system from sleep states. Moreover, it then uses full information returned by _PRW, including the GPE information, so it can take care of disabling the GPEs if necessary. Remove the code that walks the namespace and executes _PRW from ACPICA and modify comments to reflect that change. Make acpi_bus_set_run_wake_flags() disable GPEs for wakeup devices so that they don't cause spurious wakeup events to be signaled. This not only reduces the complexity of the ACPICA initialization code, but in some cases it should reduce the kernel boot time as well. Unfortunately, for this purpose we need a new ACPICA function, acpi_gpe_can_wake(), to be called by the host OS in order to disable the GPEs that can wake up the system and were previously enabled by acpi_ev_initialize_gpe_block() or acpi_ev_update_gpes() (such a GPE should be disabled only once, because the initialization code enables it only once, but it may be pointed to by _PRW for multiple devices and that's why the additional function is necessary). Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Len Brown <len.brown@intel.com>
2010-07-07 16:43:36 -06:00
out:
kfree(buffer.pointer);
return err;
}
static void acpi_wakeup_gpe_init(struct acpi_device *device)
{
struct acpi_device_id button_device_ids[] = {
{"PNP0C0C", 0},
{"PNP0C0D", 0},
{"PNP0C0E", 0},
{"", 0},
};
struct acpi_device_wakeup *wakeup = &device->wakeup;
acpi_status status;
acpi_event_status event_status;
wakeup->flags.notifier_present = 0;
/* Power button, Lid switch always enable wakeup */
if (!acpi_match_device_ids(device, button_device_ids)) {
wakeup->flags.run_wake = 1;
if (!acpi_match_device_ids(device, &button_device_ids[1])) {
/* Do not use Lid/sleep button for S5 wakeup */
if (wakeup->sleep_state == ACPI_STATE_S5)
wakeup->sleep_state = ACPI_STATE_S4;
}
acpi_mark_gpe_for_wake(wakeup->gpe_device, wakeup->gpe_number);
device_set_wakeup_capable(&device->dev, true);
return;
}
acpi_setup_gpe_for_wake(device->handle, wakeup->gpe_device,
wakeup->gpe_number);
status = acpi_get_gpe_status(wakeup->gpe_device, wakeup->gpe_number,
&event_status);
if (ACPI_FAILURE(status))
return;
wakeup->flags.run_wake = !!(event_status & ACPI_EVENT_FLAG_HAS_HANDLER);
}
static void acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
{
int err;
/* Presence of _PRW indicates wake capable */
if (!acpi_has_method(device->handle, "_PRW"))
return;
err = acpi_bus_extract_wakeup_device_power_package(device->handle,
&device->wakeup);
if (err) {
dev_err(&device->dev, "_PRW evaluation error: %d\n", err);
return;
}
device->wakeup.flags.valid = 1;
device->wakeup.prepare_count = 0;
acpi_wakeup_gpe_init(device);
/* Call _PSW/_DSW object to disable its ability to wake the sleeping
* system for the ACPI device with the _PRW object.
* The _PSW object is depreciated in ACPI 3.0 and is replaced by _DSW.
* So it is necessary to call _DSW object first. Only when it is not
* present will the _PSW object used.
*/
err = acpi_device_sleep_wake(device, 0, 0, 0);
if (err)
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
"error in _DSW or _PSW evaluation\n"));
}
static void acpi_bus_init_power_state(struct acpi_device *device, int state)
{
struct acpi_device_power_state *ps = &device->power.states[state];
char pathname[5] = { '_', 'P', 'R', '0' + state, '\0' };
struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
acpi_status status;
INIT_LIST_HEAD(&ps->resources);
/* Evaluate "_PRx" to get referenced power resources */
status = acpi_evaluate_object(device->handle, pathname, NULL, &buffer);
if (ACPI_SUCCESS(status)) {
union acpi_object *package = buffer.pointer;
if (buffer.length && package
&& package->type == ACPI_TYPE_PACKAGE
&& package->package.count) {
int err = acpi_extract_power_resources(package, 0,
&ps->resources);
if (!err)
device->power.flags.power_resources = 1;
}
ACPI_FREE(buffer.pointer);
}
/* Evaluate "_PSx" to see if we can do explicit sets */
pathname[2] = 'S';
if (acpi_has_method(device->handle, pathname))
ps->flags.explicit_set = 1;
/*
* State is valid if there are means to put the device into it.
* D3hot is only valid if _PR3 present.
*/
if (!list_empty(&ps->resources)
|| (ps->flags.explicit_set && state < ACPI_STATE_D3_HOT)) {
ps->flags.valid = 1;
ps->flags.os_accessible = 1;
}
ps->power = -1; /* Unknown - driver assigned */
ps->latency = -1; /* Unknown - driver assigned */
}
static void acpi_bus_get_power_flags(struct acpi_device *device)
{
u32 i;
/* Presence of _PS0|_PR0 indicates 'power manageable' */
if (!acpi_has_method(device->handle, "_PS0") &&
!acpi_has_method(device->handle, "_PR0"))
return;
device->flags.power_manageable = 1;
/*
* Power Management Flags
*/
if (acpi_has_method(device->handle, "_PSC"))
device->power.flags.explicit_get = 1;
if (acpi_has_method(device->handle, "_IRC"))
device->power.flags.inrush_current = 1;
if (acpi_has_method(device->handle, "_DSW"))
device->power.flags.dsw_present = 1;
/*
* Enumerate supported power management states
*/
for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++)
acpi_bus_init_power_state(device, i);
INIT_LIST_HEAD(&device->power.states[ACPI_STATE_D3_COLD].resources);
/* Set defaults for D0 and D3 states (always valid) */
device->power.states[ACPI_STATE_D0].flags.valid = 1;
device->power.states[ACPI_STATE_D0].power = 100;
device->power.states[ACPI_STATE_D3_COLD].flags.valid = 1;
device->power.states[ACPI_STATE_D3_COLD].power = 0;
ACPI / PCI / PM: Fix device PM regression related to D3hot/D3cold Commit 1cc0c998fdf2 ("ACPI: Fix D3hot v D3cold confusion") introduced a bug in __acpi_bus_set_power() and changed the behavior of acpi_pci_set_power_state() in such a way that it generally doesn't work as expected if PCI_D3hot is passed to it as the second argument. First off, if ACPI_STATE_D3 (equal to ACPI_STATE_D3_COLD) is passed to __acpi_bus_set_power() and the explicit_set flag is set for the D3cold state, the function will try to execute AML method called "_PS4", which doesn't exist. Fix this by adding a check to ensure that the name of the AML method to execute for transitions to ACPI_STATE_D3_COLD is correct in __acpi_bus_set_power(). Also make sure that the explicit_set flag for ACPI_STATE_D3_COLD will be set if _PS3 is present and modify acpi_power_transition() to avoid accessing power resources for ACPI_STATE_D3_COLD, because they don't exist. Second, if PCI_D3hot is passed to acpi_pci_set_power_state() as the target state, the function will request a transition to ACPI_STATE_D3_HOT instead of ACPI_STATE_D3. However, ACPI_STATE_D3_HOT is now only marked as supported if the _PR3 AML method is defined for the given device, which is rare. This causes problems to happen on systems where devices were successfully put into ACPI D3 by pci_set_power_state(PCI_D3hot) which doesn't work now. In particular, some unused graphics adapters are not turned off as a result. To fix this issue restore the old behavior of acpi_pci_set_power_state(), which is to request a transition to ACPI_STATE_D3 (equal to ACPI_STATE_D3_COLD) if either PCI_D3hot or PCI_D3cold is passed to it as the argument. This approach is not ideal, because generally power should not be removed from devices if PCI_D3hot is the target power state, but since this behavior is relied on, we have no choice but to restore it at the moment and spend more time on designing a better solution in the future. References: https://bugzilla.kernel.org/show_bug.cgi?id=43228 Reported-by: rocko <rockorequin@hotmail.com> Reported-by: Cristian Rodríguez <crrodriguez@opensuse.org> Reported-and-tested-by: Peter <lekensteyn@gmail.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-17 16:39:35 -06:00
/* Set D3cold's explicit_set flag if _PS3 exists. */
if (device->power.states[ACPI_STATE_D3_HOT].flags.explicit_set)
device->power.states[ACPI_STATE_D3_COLD].flags.explicit_set = 1;
/* Presence of _PS3 or _PRx means we can put the device into D3 cold */
if (device->power.states[ACPI_STATE_D3_HOT].flags.explicit_set ||
device->power.flags.power_resources)
device->power.states[ACPI_STATE_D3_COLD].flags.os_accessible = 1;
if (acpi_bus_init_power(device)) {
acpi_free_power_resources_lists(device);
device->flags.power_manageable = 0;
}
}
static void acpi_bus_get_flags(struct acpi_device *device)
{
/* Presence of _STA indicates 'dynamic_status' */
if (acpi_has_method(device->handle, "_STA"))
device->flags.dynamic_status = 1;
/* Presence of _RMV indicates 'removable' */
if (acpi_has_method(device->handle, "_RMV"))
device->flags.removable = 1;
/* Presence of _EJD|_EJ0 indicates 'ejectable' */
if (acpi_has_method(device->handle, "_EJD") ||
acpi_has_method(device->handle, "_EJ0"))
device->flags.ejectable = 1;
}
static void acpi_device_get_busid(struct acpi_device *device)
{
char bus_id[5] = { '?', 0 };
struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
int i = 0;
/*
* Bus ID
* ------
* The device's Bus ID is simply the object name.
* TBD: Shouldn't this value be unique (within the ACPI namespace)?
*/
if (ACPI_IS_ROOT_DEVICE(device)) {
strcpy(device->pnp.bus_id, "ACPI");
return;
}
switch (device->device_type) {
case ACPI_BUS_TYPE_POWER_BUTTON:
strcpy(device->pnp.bus_id, "PWRF");
break;
case ACPI_BUS_TYPE_SLEEP_BUTTON:
strcpy(device->pnp.bus_id, "SLPF");
break;
default:
acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
/* Clean up trailing underscores (if any) */
for (i = 3; i > 1; i--) {
if (bus_id[i] == '_')
bus_id[i] = '\0';
else
break;
}
strcpy(device->pnp.bus_id, bus_id);
break;
}
}
/*
* acpi_ata_match - see if an acpi object is an ATA device
*
* If an acpi object has one of the ACPI ATA methods defined,
* then we can safely call it an ATA device.
*/
bool acpi_ata_match(acpi_handle handle)
{
return acpi_has_method(handle, "_GTF") ||
acpi_has_method(handle, "_GTM") ||
acpi_has_method(handle, "_STM") ||
acpi_has_method(handle, "_SDD");
}
/*
* acpi_bay_match - see if an acpi object is an ejectable driver bay
*
* If an acpi object is ejectable and has one of the ACPI ATA methods defined,
* then we can safely call it an ejectable drive bay
*/
bool acpi_bay_match(acpi_handle handle)
{
acpi_handle phandle;
if (!acpi_has_method(handle, "_EJ0"))
return false;
if (acpi_ata_match(handle))
return true;
if (ACPI_FAILURE(acpi_get_parent(handle, &phandle)))
return false;
return acpi_ata_match(phandle);
}
bool acpi_device_is_battery(struct acpi_device *adev)
ACPI / dock: Dispatch dock notifications from the global notify handler The ACPI dock station code carries out an extra namespace scan before the main one in order to find and register all of the dock device objects. Then, it registers a notify handler for each of them for handling dock events. However, dock device objects need not be scanned for upfront. They very well can be enumerated and registered during the first phase of the main namespace scan, before attaching scan handlers and ACPI drivers to ACPI device objects. Then, the dependent devices can be added to the in the second phase. That makes it possible to drop the extra namespace scan, so do it. Moreover, it is not necessary to register notify handlers for all of the dock stations' namespace nodes, becuase notifications may be dispatched from the global notify handler for them. Do that and drop two functions used for dock notify handling, acpi_dock_deferred_cb() and dock_notify_handler(), that aren't necessary any more. Finally, some dock station objects have _HID objects matching the ACPI container scan handler which causes it to claim those objects and try to handle their hotplug, but that is not a good idea, because those objects have their own special hotplug handling anyway. For this reason, the hotplug_notify flag should not be set for ACPI device objects representing dock stations and the container scan handler should be made ignore those objects, so make that happen. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-15 17:51:01 -07:00
{
struct acpi_hardware_id *hwid;
ACPI / dock: Dispatch dock notifications from the global notify handler The ACPI dock station code carries out an extra namespace scan before the main one in order to find and register all of the dock device objects. Then, it registers a notify handler for each of them for handling dock events. However, dock device objects need not be scanned for upfront. They very well can be enumerated and registered during the first phase of the main namespace scan, before attaching scan handlers and ACPI drivers to ACPI device objects. Then, the dependent devices can be added to the in the second phase. That makes it possible to drop the extra namespace scan, so do it. Moreover, it is not necessary to register notify handlers for all of the dock stations' namespace nodes, becuase notifications may be dispatched from the global notify handler for them. Do that and drop two functions used for dock notify handling, acpi_dock_deferred_cb() and dock_notify_handler(), that aren't necessary any more. Finally, some dock station objects have _HID objects matching the ACPI container scan handler which causes it to claim those objects and try to handle their hotplug, but that is not a good idea, because those objects have their own special hotplug handling anyway. For this reason, the hotplug_notify flag should not be set for ACPI device objects representing dock stations and the container scan handler should be made ignore those objects, so make that happen. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-15 17:51:01 -07:00
list_for_each_entry(hwid, &adev->pnp.ids, list)
if (!strcmp("PNP0C0A", hwid->id))
return true;
ACPI / dock: Dispatch dock notifications from the global notify handler The ACPI dock station code carries out an extra namespace scan before the main one in order to find and register all of the dock device objects. Then, it registers a notify handler for each of them for handling dock events. However, dock device objects need not be scanned for upfront. They very well can be enumerated and registered during the first phase of the main namespace scan, before attaching scan handlers and ACPI drivers to ACPI device objects. Then, the dependent devices can be added to the in the second phase. That makes it possible to drop the extra namespace scan, so do it. Moreover, it is not necessary to register notify handlers for all of the dock stations' namespace nodes, becuase notifications may be dispatched from the global notify handler for them. Do that and drop two functions used for dock notify handling, acpi_dock_deferred_cb() and dock_notify_handler(), that aren't necessary any more. Finally, some dock station objects have _HID objects matching the ACPI container scan handler which causes it to claim those objects and try to handle their hotplug, but that is not a good idea, because those objects have their own special hotplug handling anyway. For this reason, the hotplug_notify flag should not be set for ACPI device objects representing dock stations and the container scan handler should be made ignore those objects, so make that happen. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-15 17:51:01 -07:00
return false;
ACPI / dock: Dispatch dock notifications from the global notify handler The ACPI dock station code carries out an extra namespace scan before the main one in order to find and register all of the dock device objects. Then, it registers a notify handler for each of them for handling dock events. However, dock device objects need not be scanned for upfront. They very well can be enumerated and registered during the first phase of the main namespace scan, before attaching scan handlers and ACPI drivers to ACPI device objects. Then, the dependent devices can be added to the in the second phase. That makes it possible to drop the extra namespace scan, so do it. Moreover, it is not necessary to register notify handlers for all of the dock stations' namespace nodes, becuase notifications may be dispatched from the global notify handler for them. Do that and drop two functions used for dock notify handling, acpi_dock_deferred_cb() and dock_notify_handler(), that aren't necessary any more. Finally, some dock station objects have _HID objects matching the ACPI container scan handler which causes it to claim those objects and try to handle their hotplug, but that is not a good idea, because those objects have their own special hotplug handling anyway. For this reason, the hotplug_notify flag should not be set for ACPI device objects representing dock stations and the container scan handler should be made ignore those objects, so make that happen. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-15 17:51:01 -07:00
}
static bool is_ejectable_bay(struct acpi_device *adev)
ACPI / dock: Dispatch dock notifications from the global notify handler The ACPI dock station code carries out an extra namespace scan before the main one in order to find and register all of the dock device objects. Then, it registers a notify handler for each of them for handling dock events. However, dock device objects need not be scanned for upfront. They very well can be enumerated and registered during the first phase of the main namespace scan, before attaching scan handlers and ACPI drivers to ACPI device objects. Then, the dependent devices can be added to the in the second phase. That makes it possible to drop the extra namespace scan, so do it. Moreover, it is not necessary to register notify handlers for all of the dock stations' namespace nodes, becuase notifications may be dispatched from the global notify handler for them. Do that and drop two functions used for dock notify handling, acpi_dock_deferred_cb() and dock_notify_handler(), that aren't necessary any more. Finally, some dock station objects have _HID objects matching the ACPI container scan handler which causes it to claim those objects and try to handle their hotplug, but that is not a good idea, because those objects have their own special hotplug handling anyway. For this reason, the hotplug_notify flag should not be set for ACPI device objects representing dock stations and the container scan handler should be made ignore those objects, so make that happen. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-15 17:51:01 -07:00
{
acpi_handle handle = adev->handle;
if (acpi_has_method(handle, "_EJ0") && acpi_device_is_battery(adev))
ACPI / dock: Dispatch dock notifications from the global notify handler The ACPI dock station code carries out an extra namespace scan before the main one in order to find and register all of the dock device objects. Then, it registers a notify handler for each of them for handling dock events. However, dock device objects need not be scanned for upfront. They very well can be enumerated and registered during the first phase of the main namespace scan, before attaching scan handlers and ACPI drivers to ACPI device objects. Then, the dependent devices can be added to the in the second phase. That makes it possible to drop the extra namespace scan, so do it. Moreover, it is not necessary to register notify handlers for all of the dock stations' namespace nodes, becuase notifications may be dispatched from the global notify handler for them. Do that and drop two functions used for dock notify handling, acpi_dock_deferred_cb() and dock_notify_handler(), that aren't necessary any more. Finally, some dock station objects have _HID objects matching the ACPI container scan handler which causes it to claim those objects and try to handle their hotplug, but that is not a good idea, because those objects have their own special hotplug handling anyway. For this reason, the hotplug_notify flag should not be set for ACPI device objects representing dock stations and the container scan handler should be made ignore those objects, so make that happen. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-15 17:51:01 -07:00
return true;
return acpi_bay_match(handle);
}
/*
* acpi_dock_match - see if an acpi object has a _DCK method
*/
bool acpi_dock_match(acpi_handle handle)
{
return acpi_has_method(handle, "_DCK");
}
const char *acpi_device_hid(struct acpi_device *device)
{
struct acpi_hardware_id *hid;
if (list_empty(&device->pnp.ids))
return dummy_hid;
hid = list_first_entry(&device->pnp.ids, struct acpi_hardware_id, list);
return hid->id;
}
EXPORT_SYMBOL(acpi_device_hid);
static void acpi_add_id(struct acpi_device_pnp *pnp, const char *dev_id)
{
struct acpi_hardware_id *id;
id = kmalloc(sizeof(*id), GFP_KERNEL);
if (!id)
return;
id->id = kstrdup(dev_id, GFP_KERNEL);
if (!id->id) {
kfree(id);
return;
}
list_add_tail(&id->list, &pnp->ids);
pnp->type.hardware_id = 1;
}
/*
* Old IBM workstations have a DSDT bug wherein the SMBus object
* lacks the SMBUS01 HID and the methods do not have the necessary "_"
* prefix. Work around this.
*/
static bool acpi_ibm_smbus_match(acpi_handle handle)
{
char node_name[ACPI_PATH_SEGMENT_LENGTH];
struct acpi_buffer path = { sizeof(node_name), node_name };
if (!dmi_name_in_vendors("IBM"))
return false;
/* Look for SMBS object */
if (ACPI_FAILURE(acpi_get_name(handle, ACPI_SINGLE_NAME, &path)) ||
strcmp("SMBS", path.pointer))
return false;
/* Does it have the necessary (but misnamed) methods? */
if (acpi_has_method(handle, "SBI") &&
acpi_has_method(handle, "SBR") &&
acpi_has_method(handle, "SBW"))
return true;
return false;
}
static bool acpi_object_is_system_bus(acpi_handle handle)
{
acpi_handle tmp;
if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_SB", &tmp)) &&
tmp == handle)
return true;
if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_TZ", &tmp)) &&
tmp == handle)
return true;
return false;
}
static void acpi_set_pnp_ids(acpi_handle handle, struct acpi_device_pnp *pnp,
int device_type)
{
acpi_status status;
struct acpi_device_info *info;
struct acpi_pnp_device_id_list *cid_list;
int i;
switch (device_type) {
case ACPI_BUS_TYPE_DEVICE:
if (handle == ACPI_ROOT_OBJECT) {
acpi_add_id(pnp, ACPI_SYSTEM_HID);
break;
}
status = acpi_get_object_info(handle, &info);
if (ACPI_FAILURE(status)) {
pr_err(PREFIX "%s: Error reading device info\n",
__func__);
return;
}
if (info->valid & ACPI_VALID_HID) {
acpi_add_id(pnp, info->hardware_id.string);
pnp->type.platform_id = 1;
}
if (info->valid & ACPI_VALID_CID) {
cid_list = &info->compatible_id_list;
for (i = 0; i < cid_list->count; i++)
acpi_add_id(pnp, cid_list->ids[i].string);
}
if (info->valid & ACPI_VALID_ADR) {
pnp->bus_address = info->address;
pnp->type.bus_address = 1;
}
if (info->valid & ACPI_VALID_UID)
pnp->unique_id = kstrdup(info->unique_id.string,
GFP_KERNEL);
kfree(info);
/*
* Some devices don't reliably have _HIDs & _CIDs, so add
* synthetic HIDs to make sure drivers can find them.
*/
if (acpi_is_video_device(handle))
acpi_add_id(pnp, ACPI_VIDEO_HID);
else if (acpi_bay_match(handle))
acpi_add_id(pnp, ACPI_BAY_HID);
else if (acpi_dock_match(handle))
acpi_add_id(pnp, ACPI_DOCK_HID);
else if (acpi_ibm_smbus_match(handle))
acpi_add_id(pnp, ACPI_SMBUS_IBM_HID);
else if (list_empty(&pnp->ids) &&
acpi_object_is_system_bus(handle)) {
/* \_SB, \_TZ, LNXSYBUS */
acpi_add_id(pnp, ACPI_BUS_HID);
strcpy(pnp->device_name, ACPI_BUS_DEVICE_NAME);
strcpy(pnp->device_class, ACPI_BUS_CLASS);
}
break;
case ACPI_BUS_TYPE_POWER:
acpi_add_id(pnp, ACPI_POWER_HID);
break;
case ACPI_BUS_TYPE_PROCESSOR:
acpi_add_id(pnp, ACPI_PROCESSOR_OBJECT_HID);
break;
case ACPI_BUS_TYPE_THERMAL:
acpi_add_id(pnp, ACPI_THERMAL_HID);
break;
case ACPI_BUS_TYPE_POWER_BUTTON:
acpi_add_id(pnp, ACPI_BUTTON_HID_POWERF);
break;
case ACPI_BUS_TYPE_SLEEP_BUTTON:
acpi_add_id(pnp, ACPI_BUTTON_HID_SLEEPF);
break;
}
}
void acpi_free_pnp_ids(struct acpi_device_pnp *pnp)
{
struct acpi_hardware_id *id, *tmp;
list_for_each_entry_safe(id, tmp, &pnp->ids, list) {
kfree(id->id);
kfree(id);
}
kfree(pnp->unique_id);
}
void acpi_init_device_object(struct acpi_device *device, acpi_handle handle,
int type, unsigned long long sta)
{
INIT_LIST_HEAD(&device->pnp.ids);
device->device_type = type;
device->handle = handle;
device->parent = acpi_bus_get_parent(handle);
acpi_set_device_status(device, sta);
acpi_device_get_busid(device);
acpi_set_pnp_ids(handle, &device->pnp, type);
acpi_bus_get_flags(device);
device->flags.match_driver = false;
ACPI / scan: Add acpi_device objects for all device nodes in the namespace Modify the ACPI namespace scanning code to register a struct acpi_device object for every namespace node representing a device, processor and so on, even if the device represented by that namespace node is reported to be not present and not functional by _STA. There are multiple reasons to do that. First of all, it avoids quite a lot of overhead when struct acpi_device objects are deleted every time acpi_bus_trim() is run and then added again by a subsequent acpi_bus_scan() for the same scope, although the namespace objects they correspond to stay in memory all the time (which always is the case on a vast majority of systems). Second, it will allow user space to see that there are namespace nodes representing devices that are not present at the moment and may be added to the system. It will also allow user space to evaluate _SUN for those nodes to check what physical slots the "missing" devices may be put into and it will make sense to add a sysfs attribute for _STA evaluation after this change (that will be useful for thermal management on some systems). Next, it will help to consolidate the ACPI hotplug handling among subsystems by making it possible to store hotplug-related information in struct acpi_device objects in a standard common way. Finally, it will help to avoid a race condition related to the deletion of ACPI namespace nodes. Namely, namespace nodes may be deleted as a result of a table unload triggered by _EJ0 or _DCK. If a hotplug notification for one of those nodes is triggered right before the deletion and it executes a hotplug callback via acpi_hotplug_execute(), the ACPI handle passed to that callback may be stale when the callback actually runs. One way to work around that is to always pass struct acpi_device pointers to hotplug callbacks after doing a get_device() on the objects in question which eliminates the use-after-free possibility (the ACPI handles in those objects are invalidated by acpi_scan_drop_device(), so they will trigger ACPICA errors on attempts to use them). Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2013-11-22 13:54:37 -07:00
device->flags.initialized = true;
device->flags.visited = false;
device_initialize(&device->dev);
dev_set_uevent_suppress(&device->dev, true);
}
void acpi_device_add_finalize(struct acpi_device *device)
{
dev_set_uevent_suppress(&device->dev, false);
kobject_uevent(&device->dev.kobj, KOBJ_ADD);
}
static int acpi_add_single_object(struct acpi_device **child,
acpi_handle handle, int type,
unsigned long long sta)
{
int result;
struct acpi_device *device;
struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
if (!device) {
printk(KERN_ERR PREFIX "Memory allocation error\n");
return -ENOMEM;
}
acpi_init_device_object(device, handle, type, sta);
acpi_bus_get_power_flags(device);
acpi_bus_get_wakeup_device_flags(device);
result = acpi_device_add(device, acpi_device_release);
if (result) {
acpi_device_release(&device->dev);
return result;
}
acpi_power_add_remove_device(device, true);
acpi_device_add_finalize(device);
acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Added %s [%s] parent %s\n",
dev_name(&device->dev), (char *) buffer.pointer,
device->parent ? dev_name(&device->parent->dev) : "(null)"));
kfree(buffer.pointer);
*child = device;
return 0;
}
static int acpi_bus_type_and_status(acpi_handle handle, int *type,
unsigned long long *sta)
{
acpi_status status;
acpi_object_type acpi_type;
status = acpi_get_type(handle, &acpi_type);
if (ACPI_FAILURE(status))
return -ENODEV;
switch (acpi_type) {
case ACPI_TYPE_ANY: /* for ACPI_ROOT_OBJECT */
case ACPI_TYPE_DEVICE:
*type = ACPI_BUS_TYPE_DEVICE;
status = acpi_bus_get_status_handle(handle, sta);
if (ACPI_FAILURE(status))
return -ENODEV;
break;
case ACPI_TYPE_PROCESSOR:
*type = ACPI_BUS_TYPE_PROCESSOR;
status = acpi_bus_get_status_handle(handle, sta);
if (ACPI_FAILURE(status))
return -ENODEV;
break;
case ACPI_TYPE_THERMAL:
*type = ACPI_BUS_TYPE_THERMAL;
*sta = ACPI_STA_DEFAULT;
break;
case ACPI_TYPE_POWER:
*type = ACPI_BUS_TYPE_POWER;
*sta = ACPI_STA_DEFAULT;
break;
default:
return -ENODEV;
}
return 0;
}
ACPI / scan: Add acpi_device objects for all device nodes in the namespace Modify the ACPI namespace scanning code to register a struct acpi_device object for every namespace node representing a device, processor and so on, even if the device represented by that namespace node is reported to be not present and not functional by _STA. There are multiple reasons to do that. First of all, it avoids quite a lot of overhead when struct acpi_device objects are deleted every time acpi_bus_trim() is run and then added again by a subsequent acpi_bus_scan() for the same scope, although the namespace objects they correspond to stay in memory all the time (which always is the case on a vast majority of systems). Second, it will allow user space to see that there are namespace nodes representing devices that are not present at the moment and may be added to the system. It will also allow user space to evaluate _SUN for those nodes to check what physical slots the "missing" devices may be put into and it will make sense to add a sysfs attribute for _STA evaluation after this change (that will be useful for thermal management on some systems). Next, it will help to consolidate the ACPI hotplug handling among subsystems by making it possible to store hotplug-related information in struct acpi_device objects in a standard common way. Finally, it will help to avoid a race condition related to the deletion of ACPI namespace nodes. Namely, namespace nodes may be deleted as a result of a table unload triggered by _EJ0 or _DCK. If a hotplug notification for one of those nodes is triggered right before the deletion and it executes a hotplug callback via acpi_hotplug_execute(), the ACPI handle passed to that callback may be stale when the callback actually runs. One way to work around that is to always pass struct acpi_device pointers to hotplug callbacks after doing a get_device() on the objects in question which eliminates the use-after-free possibility (the ACPI handles in those objects are invalidated by acpi_scan_drop_device(), so they will trigger ACPICA errors on attempts to use them). Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2013-11-22 13:54:37 -07:00
bool acpi_device_is_present(struct acpi_device *adev)
{
if (adev->status.present || adev->status.functional)
return true;
adev->flags.initialized = false;
return false;
}
static bool acpi_scan_handler_matching(struct acpi_scan_handler *handler,
char *idstr,
const struct acpi_device_id **matchid)
{
const struct acpi_device_id *devid;
if (handler->match)
return handler->match(idstr, matchid);
for (devid = handler->ids; devid->id[0]; devid++)
if (!strcmp((char *)devid->id, idstr)) {
if (matchid)
*matchid = devid;
return true;
}
return false;
}
static struct acpi_scan_handler *acpi_scan_match_handler(char *idstr,
const struct acpi_device_id **matchid)
{
struct acpi_scan_handler *handler;
list_for_each_entry(handler, &acpi_scan_handlers_list, list_node)
if (acpi_scan_handler_matching(handler, idstr, matchid))
return handler;
return NULL;
}
void acpi_scan_hotplug_enabled(struct acpi_hotplug_profile *hotplug, bool val)
{
if (!!hotplug->enabled == !!val)
return;
mutex_lock(&acpi_scan_lock);
hotplug->enabled = val;
mutex_unlock(&acpi_scan_lock);
}
ACPI / hotplug / PCI: Consolidate ACPIPHP with ACPI core hotplug The ACPI-based PCI hotplug (ACPIPHP) code currently attaches its hotplug context objects directly to ACPI namespace nodes representing hotplug devices. However, after recent changes causing struct acpi_device to be created for every namespace node representing a device (regardless of its status), that is not necessary any more. Moreover, it's vulnerable to the theoretical issue that the ACPI handle passed in the context between handle_hotplug_event() and hotplug_event_work() may become invalid in the meantime (as a result of a concurrent table unload). In principle, this issue might be addressed by adding a non-empty release handler for ACPIPHP hotplug context objects analogous to acpi_scan_drop_device(), but that would duplicate the code in that function and in acpi_device_del_work_fn(). For this reason, it's better to modify ACPIPHP to attach its device hotplug contexts to struct device objects representing hotplug devices and make it use acpi_hotplug_notify_cb() as its notify handler. At the same time, acpi_device_hotplug() can be modified to dispatch the new .hp.event() callback pointing to acpiphp_hotplug_event() from ACPI device objects associated with PCI devices or use the generic ACPI device hotplug code for device objects with matching scan handlers. This allows the existing code duplication between ACPIPHP and the ACPI core to be reduced too and makes further ACPI-based device hotplug consolidation possible. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-06 09:31:37 -07:00
static void acpi_scan_init_hotplug(struct acpi_device *adev)
{
struct acpi_hardware_id *hwid;
if (acpi_dock_match(adev->handle) || is_ejectable_bay(adev)) {
ACPI / dock: Dispatch dock notifications from the global notify handler The ACPI dock station code carries out an extra namespace scan before the main one in order to find and register all of the dock device objects. Then, it registers a notify handler for each of them for handling dock events. However, dock device objects need not be scanned for upfront. They very well can be enumerated and registered during the first phase of the main namespace scan, before attaching scan handlers and ACPI drivers to ACPI device objects. Then, the dependent devices can be added to the in the second phase. That makes it possible to drop the extra namespace scan, so do it. Moreover, it is not necessary to register notify handlers for all of the dock stations' namespace nodes, becuase notifications may be dispatched from the global notify handler for them. Do that and drop two functions used for dock notify handling, acpi_dock_deferred_cb() and dock_notify_handler(), that aren't necessary any more. Finally, some dock station objects have _HID objects matching the ACPI container scan handler which causes it to claim those objects and try to handle their hotplug, but that is not a good idea, because those objects have their own special hotplug handling anyway. For this reason, the hotplug_notify flag should not be set for ACPI device objects representing dock stations and the container scan handler should be made ignore those objects, so make that happen. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-15 17:51:01 -07:00
acpi_dock_add(adev);
return;
}
ACPI / hotplug / PCI: Consolidate ACPIPHP with ACPI core hotplug The ACPI-based PCI hotplug (ACPIPHP) code currently attaches its hotplug context objects directly to ACPI namespace nodes representing hotplug devices. However, after recent changes causing struct acpi_device to be created for every namespace node representing a device (regardless of its status), that is not necessary any more. Moreover, it's vulnerable to the theoretical issue that the ACPI handle passed in the context between handle_hotplug_event() and hotplug_event_work() may become invalid in the meantime (as a result of a concurrent table unload). In principle, this issue might be addressed by adding a non-empty release handler for ACPIPHP hotplug context objects analogous to acpi_scan_drop_device(), but that would duplicate the code in that function and in acpi_device_del_work_fn(). For this reason, it's better to modify ACPIPHP to attach its device hotplug contexts to struct device objects representing hotplug devices and make it use acpi_hotplug_notify_cb() as its notify handler. At the same time, acpi_device_hotplug() can be modified to dispatch the new .hp.event() callback pointing to acpiphp_hotplug_event() from ACPI device objects associated with PCI devices or use the generic ACPI device hotplug code for device objects with matching scan handlers. This allows the existing code duplication between ACPIPHP and the ACPI core to be reduced too and makes further ACPI-based device hotplug consolidation possible. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-06 09:31:37 -07:00
list_for_each_entry(hwid, &adev->pnp.ids, list) {
struct acpi_scan_handler *handler;
handler = acpi_scan_match_handler(hwid->id, NULL);
if (handler) {
adev->flags.hotplug_notify = true;
break;
}
ACPI / hotplug / PCI: Consolidate ACPIPHP with ACPI core hotplug The ACPI-based PCI hotplug (ACPIPHP) code currently attaches its hotplug context objects directly to ACPI namespace nodes representing hotplug devices. However, after recent changes causing struct acpi_device to be created for every namespace node representing a device (regardless of its status), that is not necessary any more. Moreover, it's vulnerable to the theoretical issue that the ACPI handle passed in the context between handle_hotplug_event() and hotplug_event_work() may become invalid in the meantime (as a result of a concurrent table unload). In principle, this issue might be addressed by adding a non-empty release handler for ACPIPHP hotplug context objects analogous to acpi_scan_drop_device(), but that would duplicate the code in that function and in acpi_device_del_work_fn(). For this reason, it's better to modify ACPIPHP to attach its device hotplug contexts to struct device objects representing hotplug devices and make it use acpi_hotplug_notify_cb() as its notify handler. At the same time, acpi_device_hotplug() can be modified to dispatch the new .hp.event() callback pointing to acpiphp_hotplug_event() from ACPI device objects associated with PCI devices or use the generic ACPI device hotplug code for device objects with matching scan handlers. This allows the existing code duplication between ACPIPHP and the ACPI core to be reduced too and makes further ACPI-based device hotplug consolidation possible. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-06 09:31:37 -07:00
}
}
static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl_not_used,
void *not_used, void **return_value)
{
ACPI: Separate adding ACPI device objects from probing ACPI drivers Split the ACPI namespace scanning for devices into two passes, such that struct acpi_device objects are registerd in the first pass without probing ACPI drivers and the drivers are probed against them directly in the second pass. There are two main reasons for doing that. First, the ACPI PCI root bridge driver's .add() routine, acpi_pci_root_add(), causes struct pci_dev objects to be created for all PCI devices under the given root bridge. Usually, there are corresponding ACPI device nodes in the ACPI namespace for some of those devices and therefore there should be "companion" struct acpi_device objects to attach those struct pci_dev objects to. These struct acpi_device objects should exist when the corresponding struct pci_dev objects are created, but that is only guaranteed during boot and not during hotplug. This leads to a number of functional differences between the boot and the hotplug cases which are not strictly necessary and make the code more complicated. For example, this forces the ACPI PCI root bridge driver to defer the registration of the just created struct pci_dev objects and to use a special .start() callback routine, acpi_pci_root_start(), to make sure that all of the "companion" struct acpi_device objects will be present at PCI devices registration time during hotplug. If those differences can be eliminated, we will be able to consolidate the boot and hotplug code paths for the enumeration and registration of PCI devices and to reduce the complexity of that code quite a bit. The second reason is that, in general, it should be possible to resolve conflicts of resources assigned by the BIOS to different devices represented by ACPI namespace nodes before any drivers bind to them and before they are attached to "companion" objects representing physical devices (such as struct pci_dev). However, for this purpose we first need to enumerate all ACPI device nodes in the given namespace scope. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Yinghai Lu <yinghai@kernel.org> Acked-by: Toshi Kani <toshi.kani@hp.com>
2012-12-20 16:36:39 -07:00
struct acpi_device *device = NULL;
int type;
unsigned long long sta;
int result;
acpi_bus_get_device(handle, &device);
if (device)
goto out;
result = acpi_bus_type_and_status(handle, &type, &sta);
if (result)
return AE_OK;
if (type == ACPI_BUS_TYPE_POWER) {
acpi_add_power_resource(handle);
return AE_OK;
}
acpi_add_single_object(&device, handle, type, sta);
if (!device)
return AE_CTRL_DEPTH;
ACPI / hotplug / PCI: Consolidate ACPIPHP with ACPI core hotplug The ACPI-based PCI hotplug (ACPIPHP) code currently attaches its hotplug context objects directly to ACPI namespace nodes representing hotplug devices. However, after recent changes causing struct acpi_device to be created for every namespace node representing a device (regardless of its status), that is not necessary any more. Moreover, it's vulnerable to the theoretical issue that the ACPI handle passed in the context between handle_hotplug_event() and hotplug_event_work() may become invalid in the meantime (as a result of a concurrent table unload). In principle, this issue might be addressed by adding a non-empty release handler for ACPIPHP hotplug context objects analogous to acpi_scan_drop_device(), but that would duplicate the code in that function and in acpi_device_del_work_fn(). For this reason, it's better to modify ACPIPHP to attach its device hotplug contexts to struct device objects representing hotplug devices and make it use acpi_hotplug_notify_cb() as its notify handler. At the same time, acpi_device_hotplug() can be modified to dispatch the new .hp.event() callback pointing to acpiphp_hotplug_event() from ACPI device objects associated with PCI devices or use the generic ACPI device hotplug code for device objects with matching scan handlers. This allows the existing code duplication between ACPIPHP and the ACPI core to be reduced too and makes further ACPI-based device hotplug consolidation possible. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-06 09:31:37 -07:00
acpi_scan_init_hotplug(device);
out:
if (!*return_value)
*return_value = device;
ACPI: Separate adding ACPI device objects from probing ACPI drivers Split the ACPI namespace scanning for devices into two passes, such that struct acpi_device objects are registerd in the first pass without probing ACPI drivers and the drivers are probed against them directly in the second pass. There are two main reasons for doing that. First, the ACPI PCI root bridge driver's .add() routine, acpi_pci_root_add(), causes struct pci_dev objects to be created for all PCI devices under the given root bridge. Usually, there are corresponding ACPI device nodes in the ACPI namespace for some of those devices and therefore there should be "companion" struct acpi_device objects to attach those struct pci_dev objects to. These struct acpi_device objects should exist when the corresponding struct pci_dev objects are created, but that is only guaranteed during boot and not during hotplug. This leads to a number of functional differences between the boot and the hotplug cases which are not strictly necessary and make the code more complicated. For example, this forces the ACPI PCI root bridge driver to defer the registration of the just created struct pci_dev objects and to use a special .start() callback routine, acpi_pci_root_start(), to make sure that all of the "companion" struct acpi_device objects will be present at PCI devices registration time during hotplug. If those differences can be eliminated, we will be able to consolidate the boot and hotplug code paths for the enumeration and registration of PCI devices and to reduce the complexity of that code quite a bit. The second reason is that, in general, it should be possible to resolve conflicts of resources assigned by the BIOS to different devices represented by ACPI namespace nodes before any drivers bind to them and before they are attached to "companion" objects representing physical devices (such as struct pci_dev). However, for this purpose we first need to enumerate all ACPI device nodes in the given namespace scope. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Yinghai Lu <yinghai@kernel.org> Acked-by: Toshi Kani <toshi.kani@hp.com>
2012-12-20 16:36:39 -07:00
return AE_OK;
}
static int acpi_check_spi_i2c_slave(struct acpi_resource *ares, void *data)
{
bool *is_spi_i2c_slave_p = data;
if (ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS)
return 1;
/*
* devices that are connected to UART still need to be enumerated to
* platform bus
*/
if (ares->data.common_serial_bus.type != ACPI_RESOURCE_SERIAL_TYPE_UART)
*is_spi_i2c_slave_p = true;
/* no need to do more checking */
return -1;
}
static void acpi_default_enumeration(struct acpi_device *device)
{
struct list_head resource_list;
bool is_spi_i2c_slave = false;
if (!device->pnp.type.platform_id || device->handler)
return;
/*
* Do not enemerate SPI/I2C slaves as they will be enuerated by their
* respective parents.
*/
INIT_LIST_HEAD(&resource_list);
acpi_dev_get_resources(device, &resource_list, acpi_check_spi_i2c_slave,
&is_spi_i2c_slave);
acpi_dev_free_resource_list(&resource_list);
if (!is_spi_i2c_slave)
acpi_create_platform_device(device);
}
static int acpi_scan_attach_handler(struct acpi_device *device)
{
struct acpi_hardware_id *hwid;
int ret = 0;
list_for_each_entry(hwid, &device->pnp.ids, list) {
const struct acpi_device_id *devid;
struct acpi_scan_handler *handler;
handler = acpi_scan_match_handler(hwid->id, &devid);
if (handler) {
if (!handler->attach) {
device->pnp.type.platform_id = 0;
continue;
}
device->handler = handler;
ret = handler->attach(device, devid);
if (ret > 0)
break;
device->handler = NULL;
if (ret < 0)
break;
}
}
if (!ret)
acpi_default_enumeration(device);
return ret;
}
static void acpi_bus_attach(struct acpi_device *device)
{
struct acpi_device *child;
ACPI / dock: Dispatch dock notifications from the global notify handler The ACPI dock station code carries out an extra namespace scan before the main one in order to find and register all of the dock device objects. Then, it registers a notify handler for each of them for handling dock events. However, dock device objects need not be scanned for upfront. They very well can be enumerated and registered during the first phase of the main namespace scan, before attaching scan handlers and ACPI drivers to ACPI device objects. Then, the dependent devices can be added to the in the second phase. That makes it possible to drop the extra namespace scan, so do it. Moreover, it is not necessary to register notify handlers for all of the dock stations' namespace nodes, becuase notifications may be dispatched from the global notify handler for them. Do that and drop two functions used for dock notify handling, acpi_dock_deferred_cb() and dock_notify_handler(), that aren't necessary any more. Finally, some dock station objects have _HID objects matching the ACPI container scan handler which causes it to claim those objects and try to handle their hotplug, but that is not a good idea, because those objects have their own special hotplug handling anyway. For this reason, the hotplug_notify flag should not be set for ACPI device objects representing dock stations and the container scan handler should be made ignore those objects, so make that happen. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-15 17:51:01 -07:00
acpi_handle ejd;
int ret;
ACPI / dock: Dispatch dock notifications from the global notify handler The ACPI dock station code carries out an extra namespace scan before the main one in order to find and register all of the dock device objects. Then, it registers a notify handler for each of them for handling dock events. However, dock device objects need not be scanned for upfront. They very well can be enumerated and registered during the first phase of the main namespace scan, before attaching scan handlers and ACPI drivers to ACPI device objects. Then, the dependent devices can be added to the in the second phase. That makes it possible to drop the extra namespace scan, so do it. Moreover, it is not necessary to register notify handlers for all of the dock stations' namespace nodes, becuase notifications may be dispatched from the global notify handler for them. Do that and drop two functions used for dock notify handling, acpi_dock_deferred_cb() and dock_notify_handler(), that aren't necessary any more. Finally, some dock station objects have _HID objects matching the ACPI container scan handler which causes it to claim those objects and try to handle their hotplug, but that is not a good idea, because those objects have their own special hotplug handling anyway. For this reason, the hotplug_notify flag should not be set for ACPI device objects representing dock stations and the container scan handler should be made ignore those objects, so make that happen. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-15 17:51:01 -07:00
if (ACPI_SUCCESS(acpi_bus_get_ejd(device->handle, &ejd)))
register_dock_dependent_device(device, ejd);
acpi_bus_get_status(device);
ACPI / scan: Add acpi_device objects for all device nodes in the namespace Modify the ACPI namespace scanning code to register a struct acpi_device object for every namespace node representing a device, processor and so on, even if the device represented by that namespace node is reported to be not present and not functional by _STA. There are multiple reasons to do that. First of all, it avoids quite a lot of overhead when struct acpi_device objects are deleted every time acpi_bus_trim() is run and then added again by a subsequent acpi_bus_scan() for the same scope, although the namespace objects they correspond to stay in memory all the time (which always is the case on a vast majority of systems). Second, it will allow user space to see that there are namespace nodes representing devices that are not present at the moment and may be added to the system. It will also allow user space to evaluate _SUN for those nodes to check what physical slots the "missing" devices may be put into and it will make sense to add a sysfs attribute for _STA evaluation after this change (that will be useful for thermal management on some systems). Next, it will help to consolidate the ACPI hotplug handling among subsystems by making it possible to store hotplug-related information in struct acpi_device objects in a standard common way. Finally, it will help to avoid a race condition related to the deletion of ACPI namespace nodes. Namely, namespace nodes may be deleted as a result of a table unload triggered by _EJ0 or _DCK. If a hotplug notification for one of those nodes is triggered right before the deletion and it executes a hotplug callback via acpi_hotplug_execute(), the ACPI handle passed to that callback may be stale when the callback actually runs. One way to work around that is to always pass struct acpi_device pointers to hotplug callbacks after doing a get_device() on the objects in question which eliminates the use-after-free possibility (the ACPI handles in those objects are invalidated by acpi_scan_drop_device(), so they will trigger ACPICA errors on attempts to use them). Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2013-11-22 13:54:37 -07:00
/* Skip devices that are not present. */
if (!acpi_device_is_present(device)) {
device->flags.visited = false;
return;
}
if (device->handler)
goto ok;
ACPI / scan: Add acpi_device objects for all device nodes in the namespace Modify the ACPI namespace scanning code to register a struct acpi_device object for every namespace node representing a device, processor and so on, even if the device represented by that namespace node is reported to be not present and not functional by _STA. There are multiple reasons to do that. First of all, it avoids quite a lot of overhead when struct acpi_device objects are deleted every time acpi_bus_trim() is run and then added again by a subsequent acpi_bus_scan() for the same scope, although the namespace objects they correspond to stay in memory all the time (which always is the case on a vast majority of systems). Second, it will allow user space to see that there are namespace nodes representing devices that are not present at the moment and may be added to the system. It will also allow user space to evaluate _SUN for those nodes to check what physical slots the "missing" devices may be put into and it will make sense to add a sysfs attribute for _STA evaluation after this change (that will be useful for thermal management on some systems). Next, it will help to consolidate the ACPI hotplug handling among subsystems by making it possible to store hotplug-related information in struct acpi_device objects in a standard common way. Finally, it will help to avoid a race condition related to the deletion of ACPI namespace nodes. Namely, namespace nodes may be deleted as a result of a table unload triggered by _EJ0 or _DCK. If a hotplug notification for one of those nodes is triggered right before the deletion and it executes a hotplug callback via acpi_hotplug_execute(), the ACPI handle passed to that callback may be stale when the callback actually runs. One way to work around that is to always pass struct acpi_device pointers to hotplug callbacks after doing a get_device() on the objects in question which eliminates the use-after-free possibility (the ACPI handles in those objects are invalidated by acpi_scan_drop_device(), so they will trigger ACPICA errors on attempts to use them). Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2013-11-22 13:54:37 -07:00
if (!device->flags.initialized) {
acpi_bus_update_power(device, NULL);
device->flags.initialized = true;
}
device->flags.visited = false;
ret = acpi_scan_attach_handler(device);
if (ret < 0)
return;
device->flags.match_driver = true;
if (!ret) {
ret = device_attach(&device->dev);
if (ret < 0)
return;
}
ACPI / scan: Add acpi_device objects for all device nodes in the namespace Modify the ACPI namespace scanning code to register a struct acpi_device object for every namespace node representing a device, processor and so on, even if the device represented by that namespace node is reported to be not present and not functional by _STA. There are multiple reasons to do that. First of all, it avoids quite a lot of overhead when struct acpi_device objects are deleted every time acpi_bus_trim() is run and then added again by a subsequent acpi_bus_scan() for the same scope, although the namespace objects they correspond to stay in memory all the time (which always is the case on a vast majority of systems). Second, it will allow user space to see that there are namespace nodes representing devices that are not present at the moment and may be added to the system. It will also allow user space to evaluate _SUN for those nodes to check what physical slots the "missing" devices may be put into and it will make sense to add a sysfs attribute for _STA evaluation after this change (that will be useful for thermal management on some systems). Next, it will help to consolidate the ACPI hotplug handling among subsystems by making it possible to store hotplug-related information in struct acpi_device objects in a standard common way. Finally, it will help to avoid a race condition related to the deletion of ACPI namespace nodes. Namely, namespace nodes may be deleted as a result of a table unload triggered by _EJ0 or _DCK. If a hotplug notification for one of those nodes is triggered right before the deletion and it executes a hotplug callback via acpi_hotplug_execute(), the ACPI handle passed to that callback may be stale when the callback actually runs. One way to work around that is to always pass struct acpi_device pointers to hotplug callbacks after doing a get_device() on the objects in question which eliminates the use-after-free possibility (the ACPI handles in those objects are invalidated by acpi_scan_drop_device(), so they will trigger ACPICA errors on attempts to use them). Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2013-11-22 13:54:37 -07:00
device->flags.visited = true;
ok:
list_for_each_entry(child, &device->children, node)
acpi_bus_attach(child);
if (device->handler && device->handler->hotplug.notify_online)
device->handler->hotplug.notify_online(device);
}
/**
* acpi_bus_scan - Add ACPI device node objects in a given namespace scope.
* @handle: Root of the namespace scope to scan.
*
* Scan a given ACPI tree (probably recently hot-plugged) and create and add
* found devices.
*
* If no devices were found, -ENODEV is returned, but it does not mean that
* there has been a real error. There just have been no suitable ACPI objects
* in the table trunk from which the kernel could create a device and add an
* appropriate driver.
ACPI / hotplug: Fix concurrency issues and memory leaks This changeset is aimed at fixing a few different but related problems in the ACPI hotplug infrastructure. First of all, since notify handlers may be run in parallel with acpi_bus_scan(), acpi_bus_trim() and acpi_bus_hot_remove_device() and some of them are installed for ACPI handles that have no struct acpi_device objects attached (i.e. before those objects are created), those notify handlers have to take acpi_scan_lock to prevent races from taking place (e.g. a struct acpi_device is found to be present for the given ACPI handle, but right after that it is removed by acpi_bus_trim() running in parallel to the given notify handler). Moreover, since some of them call acpi_bus_scan() and acpi_bus_trim(), this leads to the conclusion that acpi_scan_lock should be acquired by the callers of these two funtions rather by these functions themselves. For these reasons, make all notify handlers that can handle device addition and eject events take acpi_scan_lock and remove the acpi_scan_lock locking from acpi_bus_scan() and acpi_bus_trim(). Accordingly, update all of their users to make sure that they are always called under acpi_scan_lock. Furthermore, since eject operations are carried out asynchronously with respect to the notify events that trigger them, with the help of acpi_bus_hot_remove_device(), even if notify handlers take the ACPI scan lock, it still is possible that, for example, acpi_bus_trim() will run between acpi_bus_hot_remove_device() and the notify handler that scheduled its execution and that acpi_bus_trim() will remove the device node passed to acpi_bus_hot_remove_device() for ejection. In that case, the struct acpi_device object obtained by acpi_bus_hot_remove_device() will be invalid and not-so-funny things will ensue. To protect agaist that, make the users of acpi_bus_hot_remove_device() run get_device() on ACPI device node objects that are about to be passed to it and make acpi_bus_hot_remove_device() run put_device() on them and check if their ACPI handles are not NULL (make acpi_device_unregister() clear the device nodes' ACPI handles for that check to work). Finally, observe that acpi_os_hotplug_execute() actually can fail, in which case its caller ought to free memory allocated for the context object to prevent leaks from happening. It also needs to run put_device() on the device node that it ran get_device() on previously in that case. Modify the code accordingly. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Yinghai Lu <yinghai@kernel.org>
2013-02-13 06:36:47 -07:00
*
* Must be called under acpi_scan_lock.
*/
int acpi_bus_scan(acpi_handle handle)
{
void *device = NULL;
if (ACPI_SUCCESS(acpi_bus_check_add(handle, 0, NULL, &device)))
acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
acpi_bus_check_add, NULL, NULL, &device);
if (device) {
acpi_bus_attach(device);
return 0;
}
return -ENODEV;
}
EXPORT_SYMBOL(acpi_bus_scan);
ACPI / hotplug: Fix concurrency issues and memory leaks This changeset is aimed at fixing a few different but related problems in the ACPI hotplug infrastructure. First of all, since notify handlers may be run in parallel with acpi_bus_scan(), acpi_bus_trim() and acpi_bus_hot_remove_device() and some of them are installed for ACPI handles that have no struct acpi_device objects attached (i.e. before those objects are created), those notify handlers have to take acpi_scan_lock to prevent races from taking place (e.g. a struct acpi_device is found to be present for the given ACPI handle, but right after that it is removed by acpi_bus_trim() running in parallel to the given notify handler). Moreover, since some of them call acpi_bus_scan() and acpi_bus_trim(), this leads to the conclusion that acpi_scan_lock should be acquired by the callers of these two funtions rather by these functions themselves. For these reasons, make all notify handlers that can handle device addition and eject events take acpi_scan_lock and remove the acpi_scan_lock locking from acpi_bus_scan() and acpi_bus_trim(). Accordingly, update all of their users to make sure that they are always called under acpi_scan_lock. Furthermore, since eject operations are carried out asynchronously with respect to the notify events that trigger them, with the help of acpi_bus_hot_remove_device(), even if notify handlers take the ACPI scan lock, it still is possible that, for example, acpi_bus_trim() will run between acpi_bus_hot_remove_device() and the notify handler that scheduled its execution and that acpi_bus_trim() will remove the device node passed to acpi_bus_hot_remove_device() for ejection. In that case, the struct acpi_device object obtained by acpi_bus_hot_remove_device() will be invalid and not-so-funny things will ensue. To protect agaist that, make the users of acpi_bus_hot_remove_device() run get_device() on ACPI device node objects that are about to be passed to it and make acpi_bus_hot_remove_device() run put_device() on them and check if their ACPI handles are not NULL (make acpi_device_unregister() clear the device nodes' ACPI handles for that check to work). Finally, observe that acpi_os_hotplug_execute() actually can fail, in which case its caller ought to free memory allocated for the context object to prevent leaks from happening. It also needs to run put_device() on the device node that it ran get_device() on previously in that case. Modify the code accordingly. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Yinghai Lu <yinghai@kernel.org>
2013-02-13 06:36:47 -07:00
/**
* acpi_bus_trim - Detach scan handlers and drivers from ACPI device objects.
* @adev: Root of the ACPI namespace scope to walk.
ACPI / hotplug: Fix concurrency issues and memory leaks This changeset is aimed at fixing a few different but related problems in the ACPI hotplug infrastructure. First of all, since notify handlers may be run in parallel with acpi_bus_scan(), acpi_bus_trim() and acpi_bus_hot_remove_device() and some of them are installed for ACPI handles that have no struct acpi_device objects attached (i.e. before those objects are created), those notify handlers have to take acpi_scan_lock to prevent races from taking place (e.g. a struct acpi_device is found to be present for the given ACPI handle, but right after that it is removed by acpi_bus_trim() running in parallel to the given notify handler). Moreover, since some of them call acpi_bus_scan() and acpi_bus_trim(), this leads to the conclusion that acpi_scan_lock should be acquired by the callers of these two funtions rather by these functions themselves. For these reasons, make all notify handlers that can handle device addition and eject events take acpi_scan_lock and remove the acpi_scan_lock locking from acpi_bus_scan() and acpi_bus_trim(). Accordingly, update all of their users to make sure that they are always called under acpi_scan_lock. Furthermore, since eject operations are carried out asynchronously with respect to the notify events that trigger them, with the help of acpi_bus_hot_remove_device(), even if notify handlers take the ACPI scan lock, it still is possible that, for example, acpi_bus_trim() will run between acpi_bus_hot_remove_device() and the notify handler that scheduled its execution and that acpi_bus_trim() will remove the device node passed to acpi_bus_hot_remove_device() for ejection. In that case, the struct acpi_device object obtained by acpi_bus_hot_remove_device() will be invalid and not-so-funny things will ensue. To protect agaist that, make the users of acpi_bus_hot_remove_device() run get_device() on ACPI device node objects that are about to be passed to it and make acpi_bus_hot_remove_device() run put_device() on them and check if their ACPI handles are not NULL (make acpi_device_unregister() clear the device nodes' ACPI handles for that check to work). Finally, observe that acpi_os_hotplug_execute() actually can fail, in which case its caller ought to free memory allocated for the context object to prevent leaks from happening. It also needs to run put_device() on the device node that it ran get_device() on previously in that case. Modify the code accordingly. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Yinghai Lu <yinghai@kernel.org>
2013-02-13 06:36:47 -07:00
*
* Must be called under acpi_scan_lock.
*/
void acpi_bus_trim(struct acpi_device *adev)
{
struct acpi_scan_handler *handler = adev->handler;
struct acpi_device *child;
list_for_each_entry_reverse(child, &adev->children, node)
acpi_bus_trim(child);
adev->flags.match_driver = false;
if (handler) {
if (handler->detach)
handler->detach(adev);
adev->handler = NULL;
} else {
device_release_driver(&adev->dev);
}
/*
* Most likely, the device is going away, so put it into D3cold before
* that.
*/
acpi_device_set_power(adev, ACPI_STATE_D3_COLD);
adev->flags.initialized = false;
adev->flags.visited = false;
}
EXPORT_SYMBOL_GPL(acpi_bus_trim);
static int acpi_bus_scan_fixed(void)
{
int result = 0;
/*
* Enumerate all fixed-feature devices.
*/
if (!(acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON)) {
struct acpi_device *device = NULL;
result = acpi_add_single_object(&device, NULL,
ACPI_BUS_TYPE_POWER_BUTTON,
ACPI_STA_DEFAULT);
if (result)
return result;
device->flags.match_driver = true;
result = device_attach(&device->dev);
if (result < 0)
return result;
device_init_wakeup(&device->dev, true);
}
if (!(acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON)) {
struct acpi_device *device = NULL;
result = acpi_add_single_object(&device, NULL,
ACPI_BUS_TYPE_SLEEP_BUTTON,
ACPI_STA_DEFAULT);
if (result)
return result;
device->flags.match_driver = true;
result = device_attach(&device->dev);
}
return result < 0 ? result : 0;
}
int __init acpi_scan_init(void)
{
int result;
result = bus_register(&acpi_bus_type);
if (result) {
/* We don't want to quit even if we failed to add suspend/resume */
printk(KERN_ERR PREFIX "Could not register bus type\n");
}
acpi_pci_root_init();
acpi_pci_link_init();
ACPI / processor: Use common hotplug infrastructure Split the ACPI processor driver into two parts, one that is non-modular, resides in the ACPI core and handles the enumeration and hotplug of processors and one that implements the rest of the existing processor driver functionality. The non-modular part uses an ACPI scan handler object to enumerate processors on the basis of information provided by the ACPI namespace and to hook up with the common ACPI hotplug infrastructure. It also populates the ACPI handle of each processor device having a corresponding object in the ACPI namespace, which allows the driver proper to bind to those devices, and makes the driver bind to them if it is readily available (i.e. loaded) when the scan handler's .attach() routine is running. There are a few reasons to make this change. First, switching the ACPI processor driver to using the common ACPI hotplug infrastructure reduces code duplication and size considerably, even though a new file is created along with a header comment etc. Second, since the common hotplug code attempts to offline devices before starting the (non-reversible) removal procedure, it will abort (and possibly roll back) hot-remove operations involving processors if cpu_down() returns an error code for one of them instead of continuing them blindly (if /sys/firmware/acpi/hotplug/force_remove is unset). That is a more desirable behavior than what the current code does. Finally, the separation of the scan/hotplug part from the driver proper makes it possible to simplify the driver's .remove() routine, because it doesn't need to worry about the possible cleanup related to processor removal any more (the scan/hotplug part is responsible for that now) and can handle device removal and driver removal symmetricaly (i.e. as appropriate). Some user-visible changes in sysfs are made (for example, the 'sysdev' link from the ACPI device node to the processor device's directory is gone and a 'physical_node' link is present instead and a corresponding 'firmware_node' is present in the processor device's directory, the processor driver is now visible under /sys/bus/cpu/drivers/ and bound to the processor device), but that shouldn't affect the functionality that users care about (frequency scaling, C-states and thermal management). Tested on my venerable Toshiba Portege R500. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Toshi Kani <toshi.kani@hp.com>
2013-05-02 16:26:22 -06:00
acpi_processor_init();
ACPI / scan: Add special handler for Intel Lynxpoint LPSS devices Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have some common features that aren't shared with any other platform devices, including the clock and LTR (Latency Tolerance Reporting) registers. It is better to handle those features in common code than to bother device drivers with doing that (I/O functionality-wise the LPSS devices are generally compatible with other devices that don't have those special registers and may be handled by the same drivers). The clock registers of the LPSS devices are now taken care of by the special clk-x86-lpss driver, but the MMIO mappings used for accessing those registers can also be used for accessing the LTR registers on those devices (LTR support for the Lynxpoint LPSS is going to be added by a subsequent patch). Thus it is convenient to add a special ACPI scan handler for the Lynxpoint LPSS devices that will create the MMIO mappings for accessing the clock (and LTR in the future) registers and will register the LPSS devices' clocks, so the clk-x86-lpss driver will only need to take care of the main Lynxpoint LPSS clock. Introduce a special ACPI scan handler for Intel Lynxpoint LPSS devices as described above. This also reduces overhead related to browsing the ACPI namespace in search of the LPSS devices before the registration of their clocks, removes some LPSS-specific (and somewhat ugly) code from acpi_platform.c and shrinks the overall code size slightly. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Mike Turquette <mturquette@linaro.org>
2013-03-06 15:46:20 -07:00
acpi_lpss_init();
acpi_cmos_rtc_init();
acpi_container_init();
acpi_memory_hotplug_init();
ACPI / PNP: use device ID list for PNPACPI device enumeration ACPI can be used to enumerate PNP devices, but the code does not handle this in the right way currently. Namely, if an ACPI device object 1. Has a _CRS method, 2. Has an identification of "three capital characters followed by four hex digits", 3. Is not in the excluded IDs list, it will be enumerated to PNP bus (that is, a PNP device object will be create for it). This means that, actually, the PNP bus type is used as the default bus type for enumerating _HID devices in ACPI. However, more and more _HID devices need to be enumerated to the platform bus instead (that is, platform device objects need to be created for them). As a result, the device ID list in acpi_platform.c is used to enforce creating platform device objects rather than PNP device objects for matching devices. That list has been continuously growing recently, unfortunately, and it is pretty much guaranteed to grow even more in the future. To address that problem it is better to enumerate _HID devices as platform devices by default. To this end, change the way of enumerating PNP devices by adding a PNP ACPI scan handler that will use a device ID list to create PNP devices for the ACPI device objects whose device IDs are present in that list. The initial device ID list in the PNP ACPI scan handler contains all of the pnp_device_id strings from all the existing PNP drivers, so this change should be transparent to the PNP core and all of the PNP drivers. Still, in the future it should be possible to reduce its size by converting PNP drivers that need not be PNP for any technical reasons into platform drivers. Signed-off-by: Zhang Rui <rui.zhang@intel.com> [rjw: Rewrote the changelog, modified the PNP ACPI scan handler code] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2014-05-29 20:23:01 -06:00
acpi_pnp_init();
acpi_int340x_thermal_init();
ACPI / hotplug: Fix concurrency issues and memory leaks This changeset is aimed at fixing a few different but related problems in the ACPI hotplug infrastructure. First of all, since notify handlers may be run in parallel with acpi_bus_scan(), acpi_bus_trim() and acpi_bus_hot_remove_device() and some of them are installed for ACPI handles that have no struct acpi_device objects attached (i.e. before those objects are created), those notify handlers have to take acpi_scan_lock to prevent races from taking place (e.g. a struct acpi_device is found to be present for the given ACPI handle, but right after that it is removed by acpi_bus_trim() running in parallel to the given notify handler). Moreover, since some of them call acpi_bus_scan() and acpi_bus_trim(), this leads to the conclusion that acpi_scan_lock should be acquired by the callers of these two funtions rather by these functions themselves. For these reasons, make all notify handlers that can handle device addition and eject events take acpi_scan_lock and remove the acpi_scan_lock locking from acpi_bus_scan() and acpi_bus_trim(). Accordingly, update all of their users to make sure that they are always called under acpi_scan_lock. Furthermore, since eject operations are carried out asynchronously with respect to the notify events that trigger them, with the help of acpi_bus_hot_remove_device(), even if notify handlers take the ACPI scan lock, it still is possible that, for example, acpi_bus_trim() will run between acpi_bus_hot_remove_device() and the notify handler that scheduled its execution and that acpi_bus_trim() will remove the device node passed to acpi_bus_hot_remove_device() for ejection. In that case, the struct acpi_device object obtained by acpi_bus_hot_remove_device() will be invalid and not-so-funny things will ensue. To protect agaist that, make the users of acpi_bus_hot_remove_device() run get_device() on ACPI device node objects that are about to be passed to it and make acpi_bus_hot_remove_device() run put_device() on them and check if their ACPI handles are not NULL (make acpi_device_unregister() clear the device nodes' ACPI handles for that check to work). Finally, observe that acpi_os_hotplug_execute() actually can fail, in which case its caller ought to free memory allocated for the context object to prevent leaks from happening. It also needs to run put_device() on the device node that it ran get_device() on previously in that case. Modify the code accordingly. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Yinghai Lu <yinghai@kernel.org>
2013-02-13 06:36:47 -07:00
mutex_lock(&acpi_scan_lock);
/*
* Enumerate devices in the ACPI namespace.
*/
result = acpi_bus_scan(ACPI_ROOT_OBJECT);
if (result)
ACPI / hotplug: Fix concurrency issues and memory leaks This changeset is aimed at fixing a few different but related problems in the ACPI hotplug infrastructure. First of all, since notify handlers may be run in parallel with acpi_bus_scan(), acpi_bus_trim() and acpi_bus_hot_remove_device() and some of them are installed for ACPI handles that have no struct acpi_device objects attached (i.e. before those objects are created), those notify handlers have to take acpi_scan_lock to prevent races from taking place (e.g. a struct acpi_device is found to be present for the given ACPI handle, but right after that it is removed by acpi_bus_trim() running in parallel to the given notify handler). Moreover, since some of them call acpi_bus_scan() and acpi_bus_trim(), this leads to the conclusion that acpi_scan_lock should be acquired by the callers of these two funtions rather by these functions themselves. For these reasons, make all notify handlers that can handle device addition and eject events take acpi_scan_lock and remove the acpi_scan_lock locking from acpi_bus_scan() and acpi_bus_trim(). Accordingly, update all of their users to make sure that they are always called under acpi_scan_lock. Furthermore, since eject operations are carried out asynchronously with respect to the notify events that trigger them, with the help of acpi_bus_hot_remove_device(), even if notify handlers take the ACPI scan lock, it still is possible that, for example, acpi_bus_trim() will run between acpi_bus_hot_remove_device() and the notify handler that scheduled its execution and that acpi_bus_trim() will remove the device node passed to acpi_bus_hot_remove_device() for ejection. In that case, the struct acpi_device object obtained by acpi_bus_hot_remove_device() will be invalid and not-so-funny things will ensue. To protect agaist that, make the users of acpi_bus_hot_remove_device() run get_device() on ACPI device node objects that are about to be passed to it and make acpi_bus_hot_remove_device() run put_device() on them and check if their ACPI handles are not NULL (make acpi_device_unregister() clear the device nodes' ACPI handles for that check to work). Finally, observe that acpi_os_hotplug_execute() actually can fail, in which case its caller ought to free memory allocated for the context object to prevent leaks from happening. It also needs to run put_device() on the device node that it ran get_device() on previously in that case. Modify the code accordingly. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Yinghai Lu <yinghai@kernel.org>
2013-02-13 06:36:47 -07:00
goto out;
result = acpi_bus_get_device(ACPI_ROOT_OBJECT, &acpi_root);
if (result)
ACPI / hotplug: Fix concurrency issues and memory leaks This changeset is aimed at fixing a few different but related problems in the ACPI hotplug infrastructure. First of all, since notify handlers may be run in parallel with acpi_bus_scan(), acpi_bus_trim() and acpi_bus_hot_remove_device() and some of them are installed for ACPI handles that have no struct acpi_device objects attached (i.e. before those objects are created), those notify handlers have to take acpi_scan_lock to prevent races from taking place (e.g. a struct acpi_device is found to be present for the given ACPI handle, but right after that it is removed by acpi_bus_trim() running in parallel to the given notify handler). Moreover, since some of them call acpi_bus_scan() and acpi_bus_trim(), this leads to the conclusion that acpi_scan_lock should be acquired by the callers of these two funtions rather by these functions themselves. For these reasons, make all notify handlers that can handle device addition and eject events take acpi_scan_lock and remove the acpi_scan_lock locking from acpi_bus_scan() and acpi_bus_trim(). Accordingly, update all of their users to make sure that they are always called under acpi_scan_lock. Furthermore, since eject operations are carried out asynchronously with respect to the notify events that trigger them, with the help of acpi_bus_hot_remove_device(), even if notify handlers take the ACPI scan lock, it still is possible that, for example, acpi_bus_trim() will run between acpi_bus_hot_remove_device() and the notify handler that scheduled its execution and that acpi_bus_trim() will remove the device node passed to acpi_bus_hot_remove_device() for ejection. In that case, the struct acpi_device object obtained by acpi_bus_hot_remove_device() will be invalid and not-so-funny things will ensue. To protect agaist that, make the users of acpi_bus_hot_remove_device() run get_device() on ACPI device node objects that are about to be passed to it and make acpi_bus_hot_remove_device() run put_device() on them and check if their ACPI handles are not NULL (make acpi_device_unregister() clear the device nodes' ACPI handles for that check to work). Finally, observe that acpi_os_hotplug_execute() actually can fail, in which case its caller ought to free memory allocated for the context object to prevent leaks from happening. It also needs to run put_device() on the device node that it ran get_device() on previously in that case. Modify the code accordingly. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Yinghai Lu <yinghai@kernel.org>
2013-02-13 06:36:47 -07:00
goto out;
/* Fixed feature devices do not exist on HW-reduced platform */
if (!acpi_gbl_reduced_hardware) {
result = acpi_bus_scan_fixed();
if (result) {
acpi_detach_data(acpi_root->handle,
acpi_scan_drop_device);
acpi_device_del(acpi_root);
put_device(&acpi_root->dev);
goto out;
}
}
acpi_update_all_gpes();
ACPI / hotplug: Fix concurrency issues and memory leaks This changeset is aimed at fixing a few different but related problems in the ACPI hotplug infrastructure. First of all, since notify handlers may be run in parallel with acpi_bus_scan(), acpi_bus_trim() and acpi_bus_hot_remove_device() and some of them are installed for ACPI handles that have no struct acpi_device objects attached (i.e. before those objects are created), those notify handlers have to take acpi_scan_lock to prevent races from taking place (e.g. a struct acpi_device is found to be present for the given ACPI handle, but right after that it is removed by acpi_bus_trim() running in parallel to the given notify handler). Moreover, since some of them call acpi_bus_scan() and acpi_bus_trim(), this leads to the conclusion that acpi_scan_lock should be acquired by the callers of these two funtions rather by these functions themselves. For these reasons, make all notify handlers that can handle device addition and eject events take acpi_scan_lock and remove the acpi_scan_lock locking from acpi_bus_scan() and acpi_bus_trim(). Accordingly, update all of their users to make sure that they are always called under acpi_scan_lock. Furthermore, since eject operations are carried out asynchronously with respect to the notify events that trigger them, with the help of acpi_bus_hot_remove_device(), even if notify handlers take the ACPI scan lock, it still is possible that, for example, acpi_bus_trim() will run between acpi_bus_hot_remove_device() and the notify handler that scheduled its execution and that acpi_bus_trim() will remove the device node passed to acpi_bus_hot_remove_device() for ejection. In that case, the struct acpi_device object obtained by acpi_bus_hot_remove_device() will be invalid and not-so-funny things will ensue. To protect agaist that, make the users of acpi_bus_hot_remove_device() run get_device() on ACPI device node objects that are about to be passed to it and make acpi_bus_hot_remove_device() run put_device() on them and check if their ACPI handles are not NULL (make acpi_device_unregister() clear the device nodes' ACPI handles for that check to work). Finally, observe that acpi_os_hotplug_execute() actually can fail, in which case its caller ought to free memory allocated for the context object to prevent leaks from happening. It also needs to run put_device() on the device node that it ran get_device() on previously in that case. Modify the code accordingly. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Yinghai Lu <yinghai@kernel.org>
2013-02-13 06:36:47 -07:00
out:
mutex_unlock(&acpi_scan_lock);
return result;
}