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PM / Domains: Add APIs to attach/detach a PM domain for a device

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To maintain scalability let's add common methods to attach and detach
a PM domain for a device, dev_pm_domain_attach|detach().

Typically dev_pm_domain_attach() shall be invoked from subsystem level
code at the probe phase to try to attach a device to its PM domain.
The reversed actions may be done a the remove phase and then by
invoking dev_pm_domain_detach().

When attachment succeeds, the attach function should assign its
corresponding detach function to a new ->detach() callback added in the
struct dev_pm_domain.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Tested-by: Philipp Zabel <p.zabel@pengutronix.de>
Reviewed-by: Kevin Hilman <khilman@linaro.org>
Reviewed-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This commit is contained in:
Ulf Hansson 2014-09-19 20:27:37 +02:00 committed by Rafael J. Wysocki
parent aa42240ab2
commit 46420dd73b
2 changed files with 63 additions and 0 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

52
drivers/base/power/common.c
View file

@ -11,6 +11,8 @@
#include <linux/export.h>
#include <linux/slab.h>
#include <linux/pm_clock.h>
#include <linux/acpi.h>
#include <linux/pm_domain.h>
/**
* dev_pm_get_subsys_data - Create or refcount power.subsys_data for device.
@ -82,3 +84,53 @@ int dev_pm_put_subsys_data(struct device *dev)
return ret;
}
EXPORT_SYMBOL_GPL(dev_pm_put_subsys_data);
/**
* dev_pm_domain_attach - Attach a device to its PM domain.
* @dev: Device to attach.
* @power_on: Used to indicate whether we should power on the device.
*
* The @dev may only be attached to a single PM domain. By iterating through
* the available alternatives we try to find a valid PM domain for the device.
* As attachment succeeds, the ->detach() callback in the struct dev_pm_domain
* should be assigned by the corresponding attach function.
*
* This function should typically be invoked from subsystem level code during
* the probe phase. Especially for those that holds devices which requires
* power management through PM domains.
*
* Callers must ensure proper synchronization of this function with power
* management callbacks.
*
* Returns 0 on successfully attached PM domain or negative error code.
*/
int dev_pm_domain_attach(struct device *dev, bool power_on)
{
int ret;
ret = acpi_dev_pm_attach(dev, power_on);
if (ret)
ret = genpd_dev_pm_attach(dev);
return ret;
}
EXPORT_SYMBOL_GPL(dev_pm_domain_attach);
/**
* dev_pm_domain_detach - Detach a device from its PM domain.
* @dev: Device to attach.
* @power_off: Used to indicate whether we should power off the device.
*
* This functions will reverse the actions from dev_pm_domain_attach() and thus
* try to detach the @dev from its PM domain. Typically it should be invoked
* from subsystem level code during the remove phase.
*
* Callers must ensure proper synchronization of this function with power
* management callbacks.
*/
void dev_pm_domain_detach(struct device *dev, bool power_off)
{
if (dev->pm_domain && dev->pm_domain->detach)
dev->pm_domain->detach(dev, power_off);
}
EXPORT_SYMBOL_GPL(dev_pm_domain_detach);

11
include/linux/pm.h
View file

@ -622,6 +622,17 @@ struct dev_pm_domain {
void (*detach)(struct device *dev, bool power_off);
};
#ifdef CONFIG_PM
extern int dev_pm_domain_attach(struct device *dev, bool power_on);
extern void dev_pm_domain_detach(struct device *dev, bool power_off);
#else
static inline int dev_pm_domain_attach(struct device *dev, bool power_on)
{
return -ENODEV;
}
static inline void dev_pm_domain_detach(struct device *dev, bool power_off) {}
#endif
/*
* The PM_EVENT_ messages are also used by drivers implementing the legacy
* suspend framework, based on the ->suspend() and ->resume() callbacks common