diff options
Diffstat (limited to 'Documentation/power/runtime_pm.txt')
| -rw-r--r-- | Documentation/power/runtime_pm.txt | 29 |
1 files changed, 13 insertions, 16 deletions
diff --git a/Documentation/power/runtime_pm.txt b/Documentation/power/runtime_pm.txt index b6ce00b2be9a..5f96daf8566a 100644 --- a/Documentation/power/runtime_pm.txt +++ b/Documentation/power/runtime_pm.txt @@ -232,7 +232,7 @@ defined in include/linux/pm.h: equal to zero); the initial value of it is 1 (i.e. runtime PM is initially disabled for all devices) - unsigned int runtime_error; + int runtime_error; - if set, there was a fatal error (one of the callbacks returned error code as described in Section 2), so the helper funtions will not work until this flag is cleared; this is the error code returned by the failing @@ -401,11 +401,11 @@ drivers/base/power/runtime.c and include/linux/pm_runtime.h: int pm_runtime_disable(struct device *dev); - increment the device's 'power.disable_depth' field (if the value of that field was previously zero, this prevents subsystem-level runtime PM - callbacks from being run for the device), make sure that all of the pending - runtime PM operations on the device are either completed or canceled; - returns 1 if there was a resume request pending and it was necessary to - execute the subsystem-level resume callback for the device to satisfy that - request, otherwise 0 is returned + callbacks from being run for the device), make sure that all of the + pending runtime PM operations on the device are either completed or + canceled; returns 1 if there was a resume request pending and it was + necessary to execute the subsystem-level resume callback for the device + to satisfy that request, otherwise 0 is returned int pm_runtime_barrier(struct device *dev); - check if there's a resume request pending for the device and resume it @@ -667,11 +667,11 @@ driver/base/power/generic_ops.c: int pm_generic_runtime_suspend(struct device *dev); - invoke the ->runtime_suspend() callback provided by the driver of this - device and return its result, or return -EINVAL if not defined + device and return its result, or return 0 if not defined int pm_generic_runtime_resume(struct device *dev); - invoke the ->runtime_resume() callback provided by the driver of this - device and return its result, or return -EINVAL if not defined + device and return its result, or return 0 if not defined int pm_generic_suspend(struct device *dev); - if the device has not been suspended at run time, invoke the ->suspend() @@ -727,15 +727,12 @@ driver/base/power/generic_ops.c: int pm_generic_restore_noirq(struct device *dev); - invoke the ->restore_noirq() callback provided by the device's driver -These functions can be assigned to the ->runtime_idle(), ->runtime_suspend(), +These functions are the defaults used by the PM core, if a subsystem doesn't +provide its own callbacks for ->runtime_idle(), ->runtime_suspend(), ->runtime_resume(), ->suspend(), ->suspend_noirq(), ->resume(), ->resume_noirq(), ->freeze(), ->freeze_noirq(), ->thaw(), ->thaw_noirq(), -->poweroff(), ->poweroff_noirq(), ->restore(), ->restore_noirq() callback -pointers in the subsystem-level dev_pm_ops structures. - -If a subsystem wishes to use all of them at the same time, it can simply assign -the GENERIC_SUBSYS_PM_OPS macro, defined in include/linux/pm.h, to its -dev_pm_ops structure pointer. +->poweroff(), ->poweroff_noirq(), ->restore(), ->restore_noirq() in the +subsystem-level dev_pm_ops structure. Device drivers that wish to use the same function as a system suspend, freeze, poweroff and runtime suspend callback, and similarly for system resume, thaw, @@ -873,7 +870,7 @@ Here is a schematic pseudo-code example: foo->is_suspended = 0; pm_runtime_mark_last_busy(&foo->dev); if (foo->num_pending_requests > 0) - foo_process_requests(foo); + foo_process_next_request(foo); unlock(&foo->private_lock); return 0; } |