From 311aab73d273eb22be976055f6cab224f7279d5e Mon Sep 17 00:00:00 2001 From: Colin Cross Date: Mon, 8 Aug 2011 23:39:36 +0200 Subject: PM / Runtime: Add might_sleep() to runtime PM functions Some of the entry points to pm runtime are not safe to call in atomic context unless pm_runtime_irq_safe() has been called. Inspecting the code, it is not immediately obvious that the functions sleep at all, as they run inside a spin_lock_irqsave, but under some conditions they can drop the lock and turn on irqs. If a driver incorrectly calls the pm_runtime apis, it can cause sleeping and irq processing when it expects to stay in atomic context. Add might_sleep_if to the majority of the __pm_runtime_* entry points to enforce correct usage. Add pm_runtime_put_sync_autosuspend to the list of functions that can be called in atomic context. Signed-off-by: Colin Cross Reviewed-by: Kevin Hilman Signed-off-by: Rafael J. Wysocki --- Documentation/power/runtime_pm.txt | 1 + 1 file changed, 1 insertion(+) (limited to 'Documentation/power/runtime_pm.txt') diff --git a/Documentation/power/runtime_pm.txt b/Documentation/power/runtime_pm.txt index 4ce5450ab6e8..62f37bc3866f 100644 --- a/Documentation/power/runtime_pm.txt +++ b/Documentation/power/runtime_pm.txt @@ -484,6 +484,7 @@ pm_runtime_resume() pm_runtime_get_sync() pm_runtime_put_sync() pm_runtime_put_sync_suspend() +pm_runtime_put_sync_autosuspend() 5. Runtime PM Initialization, Device Probing and Removal -- cgit v1.2.3 From 2e6ba515f50ef7ddf35b2703d014d3216c9b8b24 Mon Sep 17 00:00:00 2001 From: Ming Lei Date: Wed, 21 Sep 2011 22:31:33 +0200 Subject: PM / Runtime: pm_runtime_idle() can be called in atomic context Add to pm_runtime_idle the list of functions that can be called in atomic context if pm_runtime_irq_safe() has been called for the device. Signed-off-by: Ming Lei Signed-off-by: Rafael J. Wysocki --- Documentation/power/runtime_pm.txt | 1 + 1 file changed, 1 insertion(+) (limited to 'Documentation/power/runtime_pm.txt') diff --git a/Documentation/power/runtime_pm.txt b/Documentation/power/runtime_pm.txt index 62f37bc3866f..1750740b17e8 100644 --- a/Documentation/power/runtime_pm.txt +++ b/Documentation/power/runtime_pm.txt @@ -478,6 +478,7 @@ pm_runtime_autosuspend_expiration() If pm_runtime_irq_safe() has been called for a device then the following helper functions may also be used in interrupt context: +pm_runtime_idle() pm_runtime_suspend() pm_runtime_autosuspend() pm_runtime_resume() -- cgit v1.2.3 From 2fb242adcaab5defa2f208775ac4f181ac998fdd Mon Sep 17 00:00:00 2001 From: Ming Lei Date: Sun, 9 Oct 2011 11:40:25 +0800 Subject: PM / Runtime: Update document about callbacks Support for device power domains has been introduced in commit 9659cc0678b954f187290c6e8b247a673c5d37e1 (PM: Make system-wide PM and runtime PM treat subsystems consistently), also power domain callbacks will take precedence over subsystem ones from commit 4d27e9dcff00a6425d779b065ec8892e4f391661(PM: Make power domain callbacks take precedence over subsystem ones). So update part of "Device Runtime PM Callbacks" in Documentation/power/runtime_pm.txt. Signed-off-by: Ming Lei Signed-off-by: Rafael J. Wysocki --- Documentation/power/runtime_pm.txt | 19 ++++++++++++------- 1 file changed, 12 insertions(+), 7 deletions(-) (limited to 'Documentation/power/runtime_pm.txt') diff --git a/Documentation/power/runtime_pm.txt b/Documentation/power/runtime_pm.txt index 1750740b17e8..f670836f8e5f 100644 --- a/Documentation/power/runtime_pm.txt +++ b/Documentation/power/runtime_pm.txt @@ -43,13 +43,18 @@ struct dev_pm_ops { ... }; -The ->runtime_suspend(), ->runtime_resume() and ->runtime_idle() callbacks are -executed by the PM core for either the device type, or the class (if the device -type's struct dev_pm_ops object does not exist), or the bus type (if the -device type's and class' struct dev_pm_ops objects do not exist) of the given -device (this allows device types to override callbacks provided by bus types or -classes if necessary). The bus type, device type and class callbacks are -referred to as subsystem-level callbacks in what follows. +The ->runtime_suspend(), ->runtime_resume() and ->runtime_idle() callbacks +are executed by the PM core for either the power domain, or the device type +(if the device power domain's struct dev_pm_ops does not exist), or the class +(if the device power domain's and type's struct dev_pm_ops object does not +exist), or the bus type (if the device power domain's, type's and class' +struct dev_pm_ops objects do not exist) of the given device, so the priority +order of callbacks from high to low is that power domain callbacks, device +type callbacks, class callbacks and bus type callbacks, and the high priority +one will take precedence over low priority one. The bus type, device type and +class callbacks are referred to as subsystem-level callbacks in what follows, +and generally speaking, the power domain callbacks are used for representing +power domains within a SoC. By default, the callbacks are always invoked in process context with interrupts enabled. However, subsystems can use the pm_runtime_irq_safe() helper function -- cgit v1.2.3