diff options
Diffstat (limited to 'Documentation/power')
| -rw-r--r-- | Documentation/power/drivers-testing.txt | 8 | ||||
| -rw-r--r-- | Documentation/power/runtime_pm.txt | 31 |
2 files changed, 35 insertions, 4 deletions
diff --git a/Documentation/power/drivers-testing.txt b/Documentation/power/drivers-testing.txt index 7f7a737f7f9f..638afdf4d6b8 100644 --- a/Documentation/power/drivers-testing.txt +++ b/Documentation/power/drivers-testing.txt @@ -23,10 +23,10 @@ Once you have resolved the suspend/resume-related problems with your test system without the new driver, you are ready to test it: a) Build the driver as a module, load it and try the test modes of hibernation - (see: Documents/power/basic-pm-debugging.txt, 1). + (see: Documentation/power/basic-pm-debugging.txt, 1). b) Load the driver and attempt to hibernate in the "reboot", "shutdown" and - "platform" modes (see: Documents/power/basic-pm-debugging.txt, 1). + "platform" modes (see: Documentation/power/basic-pm-debugging.txt, 1). c) Compile the driver directly into the kernel and try the test modes of hibernation. @@ -34,12 +34,12 @@ c) Compile the driver directly into the kernel and try the test modes of d) Attempt to hibernate with the driver compiled directly into the kernel in the "reboot", "shutdown" and "platform" modes. -e) Try the test modes of suspend (see: Documents/power/basic-pm-debugging.txt, +e) Try the test modes of suspend (see: Documentation/power/basic-pm-debugging.txt, 2). [As far as the STR tests are concerned, it should not matter whether or not the driver is built as a module.] f) Attempt to suspend to RAM using the s2ram tool with the driver loaded - (see: Documents/power/basic-pm-debugging.txt, 2). + (see: Documentation/power/basic-pm-debugging.txt, 2). Each of the above tests should be repeated several times and the STD tests should be mixed with the STR tests. If any of them fails, the driver cannot be diff --git a/Documentation/power/runtime_pm.txt b/Documentation/power/runtime_pm.txt index 41cc7b30d7dd..ffe55ffa540a 100644 --- a/Documentation/power/runtime_pm.txt +++ b/Documentation/power/runtime_pm.txt @@ -50,6 +50,15 @@ type's callbacks are not defined) of given device. The bus type, device type and device class callbacks are referred to as subsystem-level callbacks in what follows. +By default, the callbacks are always invoked in process context with interrupts +enabled. However, subsystems can use the pm_runtime_irq_safe() helper function +to tell the PM core that a device's ->runtime_suspend() and ->runtime_resume() +callbacks should be invoked in atomic context with interrupts disabled +(->runtime_idle() is still invoked the default way). This implies that these +callback routines must not block or sleep, but it also means that the +synchronous helper functions listed at the end of Section 4 can be used within +an interrupt handler or in an atomic context. + The subsystem-level suspend callback is _entirely_ _responsible_ for handling the suspend of the device as appropriate, which may, but need not include executing the device driver's own ->runtime_suspend() callback (from the @@ -237,6 +246,10 @@ defined in include/linux/pm.h: Section 8); it may be modified only by the pm_runtime_no_callbacks() helper function + unsigned int irq_safe; + - indicates that the ->runtime_suspend() and ->runtime_resume() callbacks + will be invoked with the spinlock held and interrupts disabled + unsigned int use_autosuspend; - indicates that the device's driver supports delayed autosuspend (see Section 9); it may be modified only by the @@ -344,6 +357,10 @@ drivers/base/power/runtime.c and include/linux/pm_runtime.h: - decrement the device's usage counter; if the result is 0 then run pm_runtime_idle(dev) and return its result + int pm_runtime_put_sync_suspend(struct device *dev); + - decrement the device's usage counter; if the result is 0 then run + pm_runtime_suspend(dev) and return its result + int pm_runtime_put_sync_autosuspend(struct device *dev); - decrement the device's usage counter; if the result is 0 then run pm_runtime_autosuspend(dev) and return its result @@ -397,6 +414,11 @@ drivers/base/power/runtime.c and include/linux/pm_runtime.h: PM attributes from /sys/devices/.../power (or prevent them from being added when the device is registered) + void pm_runtime_irq_safe(struct device *dev); + - set the power.irq_safe flag for the device, causing the runtime-PM + suspend and resume callbacks (but not the idle callback) to be invoked + with interrupts disabled + void pm_runtime_mark_last_busy(struct device *dev); - set the power.last_busy field to the current time @@ -438,6 +460,15 @@ pm_runtime_suspended() pm_runtime_mark_last_busy() 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_suspend() +pm_runtime_autosuspend() +pm_runtime_resume() +pm_runtime_get_sync() +pm_runtime_put_sync_suspend() + 5. Run-time PM Initialization, Device Probing and Removal Initially, the run-time PM is disabled for all devices, which means that the |