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authorAlan Stern <stern@rowland.harvard.edu>2015-07-15 14:40:06 +0200
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>2015-07-21 23:14:22 +0200
commit019d8817b1b064c2bacfbcf40fc68184438ad05a (patch)
treef6ac6a9eba69331a3341fa8c85f49d99a912bc41 /Documentation
parentPM / autosleep: Use workqueue for user space wakeup sources garbage collector (diff)
downloadlinux-019d8817b1b064c2bacfbcf40fc68184438ad05a.tar.xz
linux-019d8817b1b064c2bacfbcf40fc68184438ad05a.zip
PM / sleep: Allow devices without runtime PM to do direct-complete
Don't unset the direct_complete flag on devices that have runtime PM disabled, if they are runtime suspended. This is needed because otherwise ancestor devices wouldn't be able to do direct_complete without adding runtime PM support to all its descendants. Also removes pm_runtime_suspended_if_enabled() because it's now unused. Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com> Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/power/devices.txt7
-rw-r--r--Documentation/power/runtime_pm.txt4
2 files changed, 7 insertions, 4 deletions
diff --git a/Documentation/power/devices.txt b/Documentation/power/devices.txt
index d172bce0fd49..8ba6625fdd63 100644
--- a/Documentation/power/devices.txt
+++ b/Documentation/power/devices.txt
@@ -341,6 +341,13 @@ the phases are:
and is entirely responsible for bringing the device back to the
functional state as appropriate.
+ Note that this direct-complete procedure applies even if the device is
+ disabled for runtime PM; only the runtime-PM status matters. It follows
+ that if a device has system-sleep callbacks but does not support runtime
+ PM, then its prepare callback must never return a positive value. This
+ is because all devices are initially set to runtime-suspended with
+ runtime PM disabled.
+
2. The suspend methods should quiesce the device to stop it from performing
I/O. They also may save the device registers and put it into the
appropriate low-power state, depending on the bus type the device is on,
diff --git a/Documentation/power/runtime_pm.txt b/Documentation/power/runtime_pm.txt
index e76dc0ad4d2b..0784bc3a2ab5 100644
--- a/Documentation/power/runtime_pm.txt
+++ b/Documentation/power/runtime_pm.txt
@@ -445,10 +445,6 @@ drivers/base/power/runtime.c and include/linux/pm_runtime.h:
bool pm_runtime_status_suspended(struct device *dev);
- return true if the device's runtime PM status is 'suspended'
- bool pm_runtime_suspended_if_enabled(struct device *dev);
- - return true if the device's runtime PM status is 'suspended' and its
- 'power.disable_depth' field is equal to 1
-
void pm_runtime_allow(struct device *dev);
- set the power.runtime_auto flag for the device and decrease its usage
counter (used by the /sys/devices/.../power/control interface to