From 632e270e01d8a1ee9e8ea56c83028727f17b1d17 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Fri, 1 Jul 2011 22:29:15 +0200 Subject: PM / Runtime: Return special error code if runtime PM is disabled Some callers of pm_runtime_get_sync() and other runtime PM helper functions, scsi_autopm_get_host() and scsi_autopm_get_device() in particular, need to distinguish error codes returned when runtime PM is disabled (i.e. power.disable_depth is nonzero for the given device) from error codes returned in other situations. For this reason, make the runtime PM helper functions return -EACCES when power.disable_depth is nonzero and ensure that this error code won't be returned by them in any other circumstances. Modify scsi_autopm_get_host() and scsi_autopm_get_device() to check the error code returned by pm_runtime_get_sync() and ignore -EACCES. Signed-off-by: Rafael J. Wysocki --- Documentation/power/runtime_pm.txt | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'Documentation/power') diff --git a/Documentation/power/runtime_pm.txt b/Documentation/power/runtime_pm.txt index 513c52e..0ec3d61 100644 --- a/Documentation/power/runtime_pm.txt +++ b/Documentation/power/runtime_pm.txt @@ -291,7 +291,8 @@ drivers/base/power/runtime.c and include/linux/pm_runtime.h: - execute the subsystem-level suspend callback for the device; returns 0 on success, 1 if the device's run-time PM status was already 'suspended', or error code on failure, where -EAGAIN or -EBUSY means it is safe to attempt - to suspend the device again in future + to suspend the device again in future and -EACCES means that + 'power.disable_depth' is different from 0 int pm_runtime_autosuspend(struct device *dev); - same as pm_runtime_suspend() except that the autosuspend delay is taken @@ -304,7 +305,8 @@ drivers/base/power/runtime.c and include/linux/pm_runtime.h: success, 1 if the device's run-time PM status was already 'active' or error code on failure, where -EAGAIN means it may be safe to attempt to resume the device again in future, but 'power.runtime_error' should be - checked additionally + checked additionally, and -EACCES means that 'power.disable_depth' is + different from 0 int pm_request_idle(struct device *dev); - submit a request to execute the subsystem-level idle callback for the -- cgit v1.1