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 <rjw@sisk.pl>
diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c
index 5f5c423..ee99025 100644
--- a/drivers/base/power/runtime.c
+++ b/drivers/base/power/runtime.c
@@ -135,8 +135,9 @@
if (dev->power.runtime_error)
retval = -EINVAL;
- else if (atomic_read(&dev->power.usage_count) > 0
- || dev->power.disable_depth > 0)
+ else if (dev->power.disable_depth > 0)
+ retval = -EACCES;
+ else if (atomic_read(&dev->power.usage_count) > 0)
retval = -EAGAIN;
else if (!pm_children_suspended(dev))
retval = -EBUSY;
@@ -262,7 +263,7 @@
spin_lock_irq(&dev->power.lock);
}
dev->power.runtime_error = retval;
- return retval;
+ return retval != -EACCES ? retval : -EIO;
}
/**
@@ -458,7 +459,7 @@
if (dev->power.runtime_error)
retval = -EINVAL;
else if (dev->power.disable_depth > 0)
- retval = -EAGAIN;
+ retval = -EACCES;
if (retval)
goto out;