kernel-fxtec-pro1x/drivers/mmc/core/sdio_bus.c
Rafael J. Wysocki e841a7c69b mmc: sdio: Use empty system suspend/resume callbacks at the bus level
Neil Brown reports that commit 35cd133c

   PM: Run the driver callback directly if the subsystem one is not there

breaks suspend for his libertas wifi, because SDIO has a protocol
where the suspend method can return -ENOSYS and this means "There is
no point in suspending, just turn me off".  Moreover, the suspend
methods provided by SDIO drivers are not supposed to be called by
the PM core or bus-level suspend routines (which aren't presend for
SDIO).  Instead, when the SDIO core gets to suspend the device's
ancestor, it calls the device driver's suspend function, catches the
ENOSYS, and turns the device off.

The commit above breaks the SDIO core's assumption that the device
drivers' callbacks won't be executed if it doesn't provide any
bus-level callbacks.  If fact, however, this assumption has never
been really satisfied, because device class or device type suspend
might very well use the driver's callback even without that commit.

The simplest way to address this problem is to make the SDIO core
tell the PM core to ignore driver callbacks, for example by providing
no-operation suspend/resume callbacks at the bus level for it,
which is implemented by this change.

Reported-and-tested-by: Neil Brown <neilb@suse.de>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
[stable: please apply to 3.3-stable only]
Cc: <stable@vger.kernel.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
2012-04-05 20:32:26 -04:00

326 lines
7.2 KiB
C

/*
* linux/drivers/mmc/core/sdio_bus.c
*
* Copyright 2007 Pierre Ossman
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or (at
* your option) any later version.
*
* SDIO function driver model
*/
#include <linux/device.h>
#include <linux/err.h>
#include <linux/export.h>
#include <linux/slab.h>
#include <linux/pm_runtime.h>
#include <linux/mmc/card.h>
#include <linux/mmc/host.h>
#include <linux/mmc/sdio_func.h>
#include "sdio_cis.h"
#include "sdio_bus.h"
/* show configuration fields */
#define sdio_config_attr(field, format_string) \
static ssize_t \
field##_show(struct device *dev, struct device_attribute *attr, char *buf) \
{ \
struct sdio_func *func; \
\
func = dev_to_sdio_func (dev); \
return sprintf (buf, format_string, func->field); \
}
sdio_config_attr(class, "0x%02x\n");
sdio_config_attr(vendor, "0x%04x\n");
sdio_config_attr(device, "0x%04x\n");
static ssize_t modalias_show(struct device *dev, struct device_attribute *attr, char *buf)
{
struct sdio_func *func = dev_to_sdio_func (dev);
return sprintf(buf, "sdio:c%02Xv%04Xd%04X\n",
func->class, func->vendor, func->device);
}
static struct device_attribute sdio_dev_attrs[] = {
__ATTR_RO(class),
__ATTR_RO(vendor),
__ATTR_RO(device),
__ATTR_RO(modalias),
__ATTR_NULL,
};
static const struct sdio_device_id *sdio_match_one(struct sdio_func *func,
const struct sdio_device_id *id)
{
if (id->class != (__u8)SDIO_ANY_ID && id->class != func->class)
return NULL;
if (id->vendor != (__u16)SDIO_ANY_ID && id->vendor != func->vendor)
return NULL;
if (id->device != (__u16)SDIO_ANY_ID && id->device != func->device)
return NULL;
return id;
}
static const struct sdio_device_id *sdio_match_device(struct sdio_func *func,
struct sdio_driver *sdrv)
{
const struct sdio_device_id *ids;
ids = sdrv->id_table;
if (ids) {
while (ids->class || ids->vendor || ids->device) {
if (sdio_match_one(func, ids))
return ids;
ids++;
}
}
return NULL;
}
static int sdio_bus_match(struct device *dev, struct device_driver *drv)
{
struct sdio_func *func = dev_to_sdio_func(dev);
struct sdio_driver *sdrv = to_sdio_driver(drv);
if (sdio_match_device(func, sdrv))
return 1;
return 0;
}
static int
sdio_bus_uevent(struct device *dev, struct kobj_uevent_env *env)
{
struct sdio_func *func = dev_to_sdio_func(dev);
if (add_uevent_var(env,
"SDIO_CLASS=%02X", func->class))
return -ENOMEM;
if (add_uevent_var(env,
"SDIO_ID=%04X:%04X", func->vendor, func->device))
return -ENOMEM;
if (add_uevent_var(env,
"MODALIAS=sdio:c%02Xv%04Xd%04X",
func->class, func->vendor, func->device))
return -ENOMEM;
return 0;
}
static int sdio_bus_probe(struct device *dev)
{
struct sdio_driver *drv = to_sdio_driver(dev->driver);
struct sdio_func *func = dev_to_sdio_func(dev);
const struct sdio_device_id *id;
int ret;
id = sdio_match_device(func, drv);
if (!id)
return -ENODEV;
/* Unbound SDIO functions are always suspended.
* During probe, the function is set active and the usage count
* is incremented. If the driver supports runtime PM,
* it should call pm_runtime_put_noidle() in its probe routine and
* pm_runtime_get_noresume() in its remove routine.
*/
if (func->card->host->caps & MMC_CAP_POWER_OFF_CARD) {
ret = pm_runtime_get_sync(dev);
if (ret < 0)
goto out;
}
/* Set the default block size so the driver is sure it's something
* sensible. */
sdio_claim_host(func);
ret = sdio_set_block_size(func, 0);
sdio_release_host(func);
if (ret)
goto disable_runtimepm;
ret = drv->probe(func, id);
if (ret)
goto disable_runtimepm;
return 0;
disable_runtimepm:
if (func->card->host->caps & MMC_CAP_POWER_OFF_CARD)
pm_runtime_put_noidle(dev);
out:
return ret;
}
static int sdio_bus_remove(struct device *dev)
{
struct sdio_driver *drv = to_sdio_driver(dev->driver);
struct sdio_func *func = dev_to_sdio_func(dev);
int ret = 0;
/* Make sure card is powered before invoking ->remove() */
if (func->card->host->caps & MMC_CAP_POWER_OFF_CARD)
pm_runtime_get_sync(dev);
drv->remove(func);
if (func->irq_handler) {
pr_warning("WARNING: driver %s did not remove "
"its interrupt handler!\n", drv->name);
sdio_claim_host(func);
sdio_release_irq(func);
sdio_release_host(func);
}
/* First, undo the increment made directly above */
if (func->card->host->caps & MMC_CAP_POWER_OFF_CARD)
pm_runtime_put_noidle(dev);
/* Then undo the runtime PM settings in sdio_bus_probe() */
if (func->card->host->caps & MMC_CAP_POWER_OFF_CARD)
pm_runtime_put_sync(dev);
return ret;
}
#ifdef CONFIG_PM
static int pm_no_operation(struct device *dev)
{
return 0;
}
static const struct dev_pm_ops sdio_bus_pm_ops = {
SET_SYSTEM_SLEEP_PM_OPS(pm_no_operation, pm_no_operation)
SET_RUNTIME_PM_OPS(
pm_generic_runtime_suspend,
pm_generic_runtime_resume,
pm_generic_runtime_idle
)
};
#define SDIO_PM_OPS_PTR (&sdio_bus_pm_ops)
#else /* !CONFIG_PM */
#define SDIO_PM_OPS_PTR NULL
#endif /* !CONFIG_PM */
static struct bus_type sdio_bus_type = {
.name = "sdio",
.dev_attrs = sdio_dev_attrs,
.match = sdio_bus_match,
.uevent = sdio_bus_uevent,
.probe = sdio_bus_probe,
.remove = sdio_bus_remove,
.pm = SDIO_PM_OPS_PTR,
};
int sdio_register_bus(void)
{
return bus_register(&sdio_bus_type);
}
void sdio_unregister_bus(void)
{
bus_unregister(&sdio_bus_type);
}
/**
* sdio_register_driver - register a function driver
* @drv: SDIO function driver
*/
int sdio_register_driver(struct sdio_driver *drv)
{
drv->drv.name = drv->name;
drv->drv.bus = &sdio_bus_type;
return driver_register(&drv->drv);
}
EXPORT_SYMBOL_GPL(sdio_register_driver);
/**
* sdio_unregister_driver - unregister a function driver
* @drv: SDIO function driver
*/
void sdio_unregister_driver(struct sdio_driver *drv)
{
drv->drv.bus = &sdio_bus_type;
driver_unregister(&drv->drv);
}
EXPORT_SYMBOL_GPL(sdio_unregister_driver);
static void sdio_release_func(struct device *dev)
{
struct sdio_func *func = dev_to_sdio_func(dev);
sdio_free_func_cis(func);
if (func->info)
kfree(func->info);
kfree(func);
}
/*
* Allocate and initialise a new SDIO function structure.
*/
struct sdio_func *sdio_alloc_func(struct mmc_card *card)
{
struct sdio_func *func;
func = kzalloc(sizeof(struct sdio_func), GFP_KERNEL);
if (!func)
return ERR_PTR(-ENOMEM);
func->card = card;
device_initialize(&func->dev);
func->dev.parent = &card->dev;
func->dev.bus = &sdio_bus_type;
func->dev.release = sdio_release_func;
return func;
}
/*
* Register a new SDIO function with the driver model.
*/
int sdio_add_func(struct sdio_func *func)
{
int ret;
dev_set_name(&func->dev, "%s:%d", mmc_card_id(func->card), func->num);
ret = device_add(&func->dev);
if (ret == 0)
sdio_func_set_present(func);
return ret;
}
/*
* Unregister a SDIO function with the driver model, and
* (eventually) free it.
* This function can be called through error paths where sdio_add_func() was
* never executed (because a failure occurred at an earlier point).
*/
void sdio_remove_func(struct sdio_func *func)
{
if (!sdio_func_present(func))
return;
device_del(&func->dev);
put_device(&func->dev);
}