PM / Runtime: Check device PM QoS setting before "no callbacks" check

If __dev_pm_qos_read_value(dev) returns a negative value,
rpm_suspend() should return -EPERM for dev even if its
power.no_callbacks flag is set.  For this to happen, the device's
power.no_callbacks flag has to be checked after the PM QoS check,
so move the PM QoS check to rpm_check_suspend_allowed() (this will
make it cover idle notifications as well as runtime suspend too).

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Cc: stable@vger.kernel.org

diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c
index b6e9d9b7982da1a762628be31a1e2c3b539c9066..7d9c1cb1c39a7760081bae4d518efd8acf835902 100644 (file)
--- a/drivers/base/power/runtime.c
+++ b/drivers/base/power/runtime.c
@@ -147,6 +147,8 @@ static int rpm_check_suspend_allowed(struct device *dev)
            || (dev->power.request_pending
                        && dev->power.request == RPM_REQ_RESUME))
                retval = -EAGAIN;
+       else if (__dev_pm_qos_read_value(dev) < 0)
+               retval = -EPERM;
        else if (dev->power.runtime_status == RPM_SUSPENDED)
                retval = 1;
 
@@ -402,12 +404,6 @@ static int rpm_suspend(struct device *dev, int rpmflags)
                goto out;
        }
 
-       if (__dev_pm_qos_read_value(dev) < 0) {
-               /* Negative PM QoS constraint means "never suspend". */
-               retval = -EPERM;
-               goto out;
-       }
-
        __update_runtime_status(dev, RPM_SUSPENDING);
 
        if (dev->pm_domain)