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author | Ming Lei <ming.lei@canonical.com> | 2011-10-09 03:40:25 (GMT) |
---|---|---|
committer | Rafael J. Wysocki <rjw@sisk.pl> | 2011-10-10 21:37:23 (GMT) |
commit | 2fb242adcaab5defa2f208775ac4f181ac998fdd (patch) | |
tree | 2ca3dc1f23849a8f1d44d730177a1ef3e436b087 /Documentation | |
parent | 2a5306cc5f383b0e7414c75e458111afd4a563a4 (diff) | |
download | linux-2fb242adcaab5defa2f208775ac4f181ac998fdd.tar.xz |
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 <ming.lei@canonical.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Diffstat (limited to 'Documentation')
-rw-r--r-- | Documentation/power/runtime_pm.txt | 19 |
1 files changed, 12 insertions, 7 deletions
diff --git a/Documentation/power/runtime_pm.txt b/Documentation/power/runtime_pm.txt index 1750740..f670836 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 |