kernel-fxtec-pro1x/drivers/base/property.c
Linus Torvalds 2481bc7528 Power management and ACPI updates for v4.1-rc1
- Generic PM domains support update including new PM domain
    callbacks to handle device initialization better (Russell King,
    Rafael J Wysocki, Kevin Hilman).
 
  - Unified device properties API update including a new mechanism
    for accessing data provided by platform initialization code
    (Rafael J Wysocki, Adrian Hunter).
 
  - ARM cpuidle update including ARM32/ARM64 handling consolidation
    (Daniel Lezcano).
 
  - intel_idle update including support for the Silvermont Core in
    the Baytrail SOC and for the Airmont Core in the Cherrytrail and
    Braswell SOCs (Len Brown, Mathias Krause).
 
  - New cpufreq driver for Hisilicon ACPU (Leo Yan).
 
  - intel_pstate update including support for the Knights Landing
    chip (Dasaratharaman Chandramouli, Kristen Carlson Accardi).
 
  - QorIQ cpufreq driver update (Tang Yuantian, Arnd Bergmann).
 
  - powernv cpufreq driver update (Shilpasri G Bhat).
 
  - devfreq update including Tegra support changes (Tomeu Vizoso,
    MyungJoo Ham, Chanwoo Choi).
 
  - powercap RAPL (Running-Average Power Limit) driver update
    including support for Intel Broadwell server chips (Jacob Pan,
    Mathias Krause).
 
  - ACPI device enumeration update related to the handling of the
    special PRP0001 device ID allowing DT-style 'compatible' property
    to be used for ACPI device identification (Rafael J Wysocki).
 
  - ACPI EC driver update including limited _DEP support (Lan Tianyu,
    Lv Zheng).
 
  - ACPI backlight driver update including a new mechanism to allow
    native backlight handling to be forced on non-Windows 8 systems
    and a new quirk for Lenovo Ideapad Z570 (Aaron Lu, Hans de Goede).
 
  - New Windows Vista compatibility quirk for Sony VGN-SR19XN (Chen Yu).
 
  - Assorted ACPI fixes and cleanups (Aaron Lu, Martin Kepplinger,
    Masanari Iida, Mika Westerberg, Nan Li, Rafael J Wysocki).
 
  - Fixes related to suspend-to-idle for the iTCO watchdog driver and
    the ACPI core system suspend/resume code (Rafael J Wysocki, Chen Yu).
 
  - PM tracing support for the suspend phase of system suspend/resume
    transitions (Zhonghui Fu).
 
  - Configurable delay for the system suspend/resume testing facility
    (Brian Norris).
 
  - PNP subsystem cleanups (Peter Huewe, Rafael J Wysocki).
 
 /
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Merge tag 'pm+acpi-4.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management and ACPI updates from Rafael Wysocki:
 "These are mostly fixes and cleanups all over, although there are a few
  items that sort of fall into the new feature category.

  First off, we have new callbacks for PM domains that should help us to
  handle some issues related to device initialization in a better way.

  There also is some consolidation in the unified device properties API
  area allowing us to use that inferface for accessing data coming from
  platform initialization code in addition to firmware-provided data.

  We have some new device/CPU IDs in a few drivers, support for new
  chips and a new cpufreq driver too.

  Specifics:

   - Generic PM domains support update including new PM domain callbacks
     to handle device initialization better (Russell King, Rafael J
     Wysocki, Kevin Hilman)

   - Unified device properties API update including a new mechanism for
     accessing data provided by platform initialization code (Rafael J
     Wysocki, Adrian Hunter)

   - ARM cpuidle update including ARM32/ARM64 handling consolidation
     (Daniel Lezcano)

   - intel_idle update including support for the Silvermont Core in the
     Baytrail SOC and for the Airmont Core in the Cherrytrail and
     Braswell SOCs (Len Brown, Mathias Krause)

   - New cpufreq driver for Hisilicon ACPU (Leo Yan)

   - intel_pstate update including support for the Knights Landing chip
     (Dasaratharaman Chandramouli, Kristen Carlson Accardi)

   - QorIQ cpufreq driver update (Tang Yuantian, Arnd Bergmann)

   - powernv cpufreq driver update (Shilpasri G Bhat)

   - devfreq update including Tegra support changes (Tomeu Vizoso,
     MyungJoo Ham, Chanwoo Choi)

   - powercap RAPL (Running-Average Power Limit) driver update including
     support for Intel Broadwell server chips (Jacob Pan, Mathias Krause)

   - ACPI device enumeration update related to the handling of the
     special PRP0001 device ID allowing DT-style 'compatible' property
     to be used for ACPI device identification (Rafael J Wysocki)

   - ACPI EC driver update including limited _DEP support (Lan Tianyu,
     Lv Zheng)

   - ACPI backlight driver update including a new mechanism to allow
     native backlight handling to be forced on non-Windows 8 systems and
     a new quirk for Lenovo Ideapad Z570 (Aaron Lu, Hans de Goede)

   - New Windows Vista compatibility quirk for Sony VGN-SR19XN (Chen Yu)

   - Assorted ACPI fixes and cleanups (Aaron Lu, Martin Kepplinger,
     Masanari Iida, Mika Westerberg, Nan Li, Rafael J Wysocki)

   - Fixes related to suspend-to-idle for the iTCO watchdog driver and
     the ACPI core system suspend/resume code (Rafael J Wysocki, Chen Yu)

   - PM tracing support for the suspend phase of system suspend/resume
     transitions (Zhonghui Fu)

   - Configurable delay for the system suspend/resume testing facility
     (Brian Norris)

   - PNP subsystem cleanups (Peter Huewe, Rafael J Wysocki)"

* tag 'pm+acpi-4.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (74 commits)
  ACPI / scan: Fix NULL pointer dereference in acpi_companion_match()
  ACPI / scan: Rework modalias creation when "compatible" is present
  intel_idle: mark cpu id array as __initconst
  powercap / RAPL: mark rapl_ids array as __initconst
  powercap / RAPL: add ID for Broadwell server
  intel_pstate: Knights Landing support
  intel_pstate: remove MSR test
  cpufreq: fix qoriq uniprocessor build
  ACPI / scan: Take the PRP0001 position in the list of IDs into account
  ACPI / scan: Simplify acpi_match_device()
  ACPI / scan: Generalize of_compatible matching
  device property: Introduce firmware node type for platform data
  device property: Make it possible to use secondary firmware nodes
  PM / watchdog: iTCO: stop watchdog during system suspend
  cpufreq: hisilicon: add acpu driver
  ACPI / EC: Call acpi_walk_dep_device_list() after installing EC opregion handler
  cpufreq: powernv: Report cpu frequency throttling
  intel_idle: Add support for the Airmont Core in the Cherrytrail and Braswell SOCs
  intel_idle: Update support for Silvermont Core in Baytrail SOC
  PM / devfreq: tegra: Register governor on module init
  ...
2015-04-14 20:21:54 -07:00

521 lines
18 KiB
C

/*
* property.c - Unified device property interface.
*
* Copyright (C) 2014, Intel Corporation
* Authors: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* Mika Westerberg <mika.westerberg@linux.intel.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/acpi.h>
#include <linux/export.h>
#include <linux/kernel.h>
#include <linux/of.h>
#include <linux/property.h>
/**
* device_add_property_set - Add a collection of properties to a device object.
* @dev: Device to add properties to.
* @pset: Collection of properties to add.
*
* Associate a collection of device properties represented by @pset with @dev
* as its secondary firmware node.
*/
void device_add_property_set(struct device *dev, struct property_set *pset)
{
if (pset)
pset->fwnode.type = FWNODE_PDATA;
set_secondary_fwnode(dev, &pset->fwnode);
}
EXPORT_SYMBOL_GPL(device_add_property_set);
static inline bool is_pset(struct fwnode_handle *fwnode)
{
return fwnode && fwnode->type == FWNODE_PDATA;
}
static inline struct property_set *to_pset(struct fwnode_handle *fwnode)
{
return is_pset(fwnode) ?
container_of(fwnode, struct property_set, fwnode) : NULL;
}
static struct property_entry *pset_prop_get(struct property_set *pset,
const char *name)
{
struct property_entry *prop;
if (!pset || !pset->properties)
return NULL;
for (prop = pset->properties; prop->name; prop++)
if (!strcmp(name, prop->name))
return prop;
return NULL;
}
static int pset_prop_read_array(struct property_set *pset, const char *name,
enum dev_prop_type type, void *val, size_t nval)
{
struct property_entry *prop;
unsigned int item_size;
prop = pset_prop_get(pset, name);
if (!prop)
return -ENODATA;
if (prop->type != type)
return -EPROTO;
if (!val)
return prop->nval;
if (prop->nval < nval)
return -EOVERFLOW;
switch (type) {
case DEV_PROP_U8:
item_size = sizeof(u8);
break;
case DEV_PROP_U16:
item_size = sizeof(u16);
break;
case DEV_PROP_U32:
item_size = sizeof(u32);
break;
case DEV_PROP_U64:
item_size = sizeof(u64);
break;
case DEV_PROP_STRING:
item_size = sizeof(const char *);
break;
default:
return -EINVAL;
}
memcpy(val, prop->value.raw_data, nval * item_size);
return 0;
}
static inline struct fwnode_handle *dev_fwnode(struct device *dev)
{
return IS_ENABLED(CONFIG_OF) && dev->of_node ?
&dev->of_node->fwnode : dev->fwnode;
}
/**
* device_property_present - check if a property of a device is present
* @dev: Device whose property is being checked
* @propname: Name of the property
*
* Check if property @propname is present in the device firmware description.
*/
bool device_property_present(struct device *dev, const char *propname)
{
return fwnode_property_present(dev_fwnode(dev), propname);
}
EXPORT_SYMBOL_GPL(device_property_present);
/**
* fwnode_property_present - check if a property of a firmware node is present
* @fwnode: Firmware node whose property to check
* @propname: Name of the property
*/
bool fwnode_property_present(struct fwnode_handle *fwnode, const char *propname)
{
if (is_of_node(fwnode))
return of_property_read_bool(of_node(fwnode), propname);
else if (is_acpi_node(fwnode))
return !acpi_dev_prop_get(acpi_node(fwnode), propname, NULL);
return !!pset_prop_get(to_pset(fwnode), propname);
}
EXPORT_SYMBOL_GPL(fwnode_property_present);
/**
* device_property_read_u8_array - return a u8 array property of a device
* @dev: Device to get the property of
* @propname: Name of the property
* @val: The values are stored here or %NULL to return the number of values
* @nval: Size of the @val array
*
* Function reads an array of u8 properties with @propname from the device
* firmware description and stores them to @val if found.
*
* Return: number of values if @val was %NULL,
* %0 if the property was found (success),
* %-EINVAL if given arguments are not valid,
* %-ENODATA if the property does not have a value,
* %-EPROTO if the property is not an array of numbers,
* %-EOVERFLOW if the size of the property is not as expected.
*/
int device_property_read_u8_array(struct device *dev, const char *propname,
u8 *val, size_t nval)
{
return fwnode_property_read_u8_array(dev_fwnode(dev), propname, val, nval);
}
EXPORT_SYMBOL_GPL(device_property_read_u8_array);
/**
* device_property_read_u16_array - return a u16 array property of a device
* @dev: Device to get the property of
* @propname: Name of the property
* @val: The values are stored here or %NULL to return the number of values
* @nval: Size of the @val array
*
* Function reads an array of u16 properties with @propname from the device
* firmware description and stores them to @val if found.
*
* Return: number of values if @val was %NULL,
* %0 if the property was found (success),
* %-EINVAL if given arguments are not valid,
* %-ENODATA if the property does not have a value,
* %-EPROTO if the property is not an array of numbers,
* %-EOVERFLOW if the size of the property is not as expected.
*/
int device_property_read_u16_array(struct device *dev, const char *propname,
u16 *val, size_t nval)
{
return fwnode_property_read_u16_array(dev_fwnode(dev), propname, val, nval);
}
EXPORT_SYMBOL_GPL(device_property_read_u16_array);
/**
* device_property_read_u32_array - return a u32 array property of a device
* @dev: Device to get the property of
* @propname: Name of the property
* @val: The values are stored here or %NULL to return the number of values
* @nval: Size of the @val array
*
* Function reads an array of u32 properties with @propname from the device
* firmware description and stores them to @val if found.
*
* Return: number of values if @val was %NULL,
* %0 if the property was found (success),
* %-EINVAL if given arguments are not valid,
* %-ENODATA if the property does not have a value,
* %-EPROTO if the property is not an array of numbers,
* %-EOVERFLOW if the size of the property is not as expected.
*/
int device_property_read_u32_array(struct device *dev, const char *propname,
u32 *val, size_t nval)
{
return fwnode_property_read_u32_array(dev_fwnode(dev), propname, val, nval);
}
EXPORT_SYMBOL_GPL(device_property_read_u32_array);
/**
* device_property_read_u64_array - return a u64 array property of a device
* @dev: Device to get the property of
* @propname: Name of the property
* @val: The values are stored here or %NULL to return the number of values
* @nval: Size of the @val array
*
* Function reads an array of u64 properties with @propname from the device
* firmware description and stores them to @val if found.
*
* Return: number of values if @val was %NULL,
* %0 if the property was found (success),
* %-EINVAL if given arguments are not valid,
* %-ENODATA if the property does not have a value,
* %-EPROTO if the property is not an array of numbers,
* %-EOVERFLOW if the size of the property is not as expected.
*/
int device_property_read_u64_array(struct device *dev, const char *propname,
u64 *val, size_t nval)
{
return fwnode_property_read_u64_array(dev_fwnode(dev), propname, val, nval);
}
EXPORT_SYMBOL_GPL(device_property_read_u64_array);
/**
* device_property_read_string_array - return a string array property of device
* @dev: Device to get the property of
* @propname: Name of the property
* @val: The values are stored here or %NULL to return the number of values
* @nval: Size of the @val array
*
* Function reads an array of string properties with @propname from the device
* firmware description and stores them to @val if found.
*
* Return: number of values if @val was %NULL,
* %0 if the property was found (success),
* %-EINVAL if given arguments are not valid,
* %-ENODATA if the property does not have a value,
* %-EPROTO or %-EILSEQ if the property is not an array of strings,
* %-EOVERFLOW if the size of the property is not as expected.
*/
int device_property_read_string_array(struct device *dev, const char *propname,
const char **val, size_t nval)
{
return fwnode_property_read_string_array(dev_fwnode(dev), propname, val, nval);
}
EXPORT_SYMBOL_GPL(device_property_read_string_array);
/**
* device_property_read_string - return a string property of a device
* @dev: Device to get the property of
* @propname: Name of the property
* @val: The value is stored here
*
* Function reads property @propname from the device firmware description and
* stores the value into @val if found. The value is checked to be a string.
*
* Return: %0 if the property was found (success),
* %-EINVAL if given arguments are not valid,
* %-ENODATA if the property does not have a value,
* %-EPROTO or %-EILSEQ if the property type is not a string.
*/
int device_property_read_string(struct device *dev, const char *propname,
const char **val)
{
return fwnode_property_read_string(dev_fwnode(dev), propname, val);
}
EXPORT_SYMBOL_GPL(device_property_read_string);
#define OF_DEV_PROP_READ_ARRAY(node, propname, type, val, nval) \
(val) ? of_property_read_##type##_array((node), (propname), (val), (nval)) \
: of_property_count_elems_of_size((node), (propname), sizeof(type))
#define FWNODE_PROP_READ_ARRAY(_fwnode_, _propname_, _type_, _proptype_, _val_, _nval_) \
({ \
int _ret_; \
if (is_of_node(_fwnode_)) \
_ret_ = OF_DEV_PROP_READ_ARRAY(of_node(_fwnode_), _propname_, \
_type_, _val_, _nval_); \
else if (is_acpi_node(_fwnode_)) \
_ret_ = acpi_dev_prop_read(acpi_node(_fwnode_), _propname_, \
_proptype_, _val_, _nval_); \
else \
_ret_ = pset_prop_read_array(to_pset(_fwnode_), _propname_, \
_proptype_, _val_, _nval_); \
_ret_; \
})
/**
* fwnode_property_read_u8_array - return a u8 array property of firmware node
* @fwnode: Firmware node to get the property of
* @propname: Name of the property
* @val: The values are stored here or %NULL to return the number of values
* @nval: Size of the @val array
*
* Read an array of u8 properties with @propname from @fwnode and stores them to
* @val if found.
*
* Return: number of values if @val was %NULL,
* %0 if the property was found (success),
* %-EINVAL if given arguments are not valid,
* %-ENODATA if the property does not have a value,
* %-EPROTO if the property is not an array of numbers,
* %-EOVERFLOW if the size of the property is not as expected,
* %-ENXIO if no suitable firmware interface is present.
*/
int fwnode_property_read_u8_array(struct fwnode_handle *fwnode,
const char *propname, u8 *val, size_t nval)
{
return FWNODE_PROP_READ_ARRAY(fwnode, propname, u8, DEV_PROP_U8,
val, nval);
}
EXPORT_SYMBOL_GPL(fwnode_property_read_u8_array);
/**
* fwnode_property_read_u16_array - return a u16 array property of firmware node
* @fwnode: Firmware node to get the property of
* @propname: Name of the property
* @val: The values are stored here or %NULL to return the number of values
* @nval: Size of the @val array
*
* Read an array of u16 properties with @propname from @fwnode and store them to
* @val if found.
*
* Return: number of values if @val was %NULL,
* %0 if the property was found (success),
* %-EINVAL if given arguments are not valid,
* %-ENODATA if the property does not have a value,
* %-EPROTO if the property is not an array of numbers,
* %-EOVERFLOW if the size of the property is not as expected,
* %-ENXIO if no suitable firmware interface is present.
*/
int fwnode_property_read_u16_array(struct fwnode_handle *fwnode,
const char *propname, u16 *val, size_t nval)
{
return FWNODE_PROP_READ_ARRAY(fwnode, propname, u16, DEV_PROP_U16,
val, nval);
}
EXPORT_SYMBOL_GPL(fwnode_property_read_u16_array);
/**
* fwnode_property_read_u32_array - return a u32 array property of firmware node
* @fwnode: Firmware node to get the property of
* @propname: Name of the property
* @val: The values are stored here or %NULL to return the number of values
* @nval: Size of the @val array
*
* Read an array of u32 properties with @propname from @fwnode store them to
* @val if found.
*
* Return: number of values if @val was %NULL,
* %0 if the property was found (success),
* %-EINVAL if given arguments are not valid,
* %-ENODATA if the property does not have a value,
* %-EPROTO if the property is not an array of numbers,
* %-EOVERFLOW if the size of the property is not as expected,
* %-ENXIO if no suitable firmware interface is present.
*/
int fwnode_property_read_u32_array(struct fwnode_handle *fwnode,
const char *propname, u32 *val, size_t nval)
{
return FWNODE_PROP_READ_ARRAY(fwnode, propname, u32, DEV_PROP_U32,
val, nval);
}
EXPORT_SYMBOL_GPL(fwnode_property_read_u32_array);
/**
* fwnode_property_read_u64_array - return a u64 array property firmware node
* @fwnode: Firmware node to get the property of
* @propname: Name of the property
* @val: The values are stored here or %NULL to return the number of values
* @nval: Size of the @val array
*
* Read an array of u64 properties with @propname from @fwnode and store them to
* @val if found.
*
* Return: number of values if @val was %NULL,
* %0 if the property was found (success),
* %-EINVAL if given arguments are not valid,
* %-ENODATA if the property does not have a value,
* %-EPROTO if the property is not an array of numbers,
* %-EOVERFLOW if the size of the property is not as expected,
* %-ENXIO if no suitable firmware interface is present.
*/
int fwnode_property_read_u64_array(struct fwnode_handle *fwnode,
const char *propname, u64 *val, size_t nval)
{
return FWNODE_PROP_READ_ARRAY(fwnode, propname, u64, DEV_PROP_U64,
val, nval);
}
EXPORT_SYMBOL_GPL(fwnode_property_read_u64_array);
/**
* fwnode_property_read_string_array - return string array property of a node
* @fwnode: Firmware node to get the property of
* @propname: Name of the property
* @val: The values are stored here or %NULL to return the number of values
* @nval: Size of the @val array
*
* Read an string list property @propname from the given firmware node and store
* them to @val if found.
*
* Return: number of values if @val was %NULL,
* %0 if the property was found (success),
* %-EINVAL if given arguments are not valid,
* %-ENODATA if the property does not have a value,
* %-EPROTO if the property is not an array of strings,
* %-EOVERFLOW if the size of the property is not as expected,
* %-ENXIO if no suitable firmware interface is present.
*/
int fwnode_property_read_string_array(struct fwnode_handle *fwnode,
const char *propname, const char **val,
size_t nval)
{
if (is_of_node(fwnode))
return val ?
of_property_read_string_array(of_node(fwnode), propname,
val, nval) :
of_property_count_strings(of_node(fwnode), propname);
else if (is_acpi_node(fwnode))
return acpi_dev_prop_read(acpi_node(fwnode), propname,
DEV_PROP_STRING, val, nval);
return pset_prop_read_array(to_pset(fwnode), propname,
DEV_PROP_STRING, val, nval);
}
EXPORT_SYMBOL_GPL(fwnode_property_read_string_array);
/**
* fwnode_property_read_string - return a string property of a firmware node
* @fwnode: Firmware node to get the property of
* @propname: Name of the property
* @val: The value is stored here
*
* Read property @propname from the given firmware node and store the value into
* @val if found. The value is checked to be a string.
*
* Return: %0 if the property was found (success),
* %-EINVAL if given arguments are not valid,
* %-ENODATA if the property does not have a value,
* %-EPROTO or %-EILSEQ if the property is not a string,
* %-ENXIO if no suitable firmware interface is present.
*/
int fwnode_property_read_string(struct fwnode_handle *fwnode,
const char *propname, const char **val)
{
if (is_of_node(fwnode))
return of_property_read_string(of_node(fwnode), propname, val);
else if (is_acpi_node(fwnode))
return acpi_dev_prop_read(acpi_node(fwnode), propname,
DEV_PROP_STRING, val, 1);
return -ENXIO;
}
EXPORT_SYMBOL_GPL(fwnode_property_read_string);
/**
* device_get_next_child_node - Return the next child node handle for a device
* @dev: Device to find the next child node for.
* @child: Handle to one of the device's child nodes or a null handle.
*/
struct fwnode_handle *device_get_next_child_node(struct device *dev,
struct fwnode_handle *child)
{
if (IS_ENABLED(CONFIG_OF) && dev->of_node) {
struct device_node *node;
node = of_get_next_available_child(dev->of_node, of_node(child));
if (node)
return &node->fwnode;
} else if (IS_ENABLED(CONFIG_ACPI)) {
struct acpi_device *node;
node = acpi_get_next_child(dev, acpi_node(child));
if (node)
return acpi_fwnode_handle(node);
}
return NULL;
}
EXPORT_SYMBOL_GPL(device_get_next_child_node);
/**
* fwnode_handle_put - Drop reference to a device node
* @fwnode: Pointer to the device node to drop the reference to.
*
* This has to be used when terminating device_for_each_child_node() iteration
* with break or return to prevent stale device node references from being left
* behind.
*/
void fwnode_handle_put(struct fwnode_handle *fwnode)
{
if (is_of_node(fwnode))
of_node_put(of_node(fwnode));
}
EXPORT_SYMBOL_GPL(fwnode_handle_put);
/**
* device_get_child_node_count - return the number of child nodes for device
* @dev: Device to cound the child nodes for
*/
unsigned int device_get_child_node_count(struct device *dev)
{
struct fwnode_handle *child;
unsigned int count = 0;
device_for_each_child_node(dev, child)
count++;
return count;
}
EXPORT_SYMBOL_GPL(device_get_child_node_count);