1 files changed, 30 insertions, 0 deletions

diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
index 7b20801d19da..b6e29ffbb70d 100644
--- a/drivers/base/power/domain.c
+++ b/drivers/base/power/domain.c
@@ -482,6 +482,33 @@ static void pm_genpd_sync_poweroff(struct generic_pm_domain *genpd)
 }
 
 /**
+ * resume_needed - Check whether to resume a device before system suspend.
+ * @dev: Device to check.
+ * @genpd: PM domain the device belongs to.
+ *
+ * There are two cases in which a device that can wake up the system from sleep
+ * states should be resumed by pm_genpd_prepare(): (1) if the device is enabled
+ * to wake up the system and it has to remain active for this purpose while the
+ * system is in the sleep state and (2) if the device is not enabled to wake up
+ * the system from sleep states and it generally doesn't generate wakeup signals
+ * by itself (those signals are generated on its behalf by other parts of the
+ * system).  In the latter case it may be necessary to reconfigure the device's
+ * wakeup settings during system suspend, because it may have been set up to
+ * signal remote wakeup from the system's working state as needed by runtime PM.
+ * Return 'true' in either of the above cases.
+ */
+static bool resume_needed(struct device *dev, struct generic_pm_domain *genpd)
+{
+        bool active_wakeup;
+
+        if (!device_can_wakeup(dev))
+                return false;
+
+        active_wakeup = genpd->active_wakeup && genpd->active_wakeup(dev);
+        return device_may_wakeup(dev) ? active_wakeup : !active_wakeup;
+}
+
+/**
  * pm_genpd_prepare - Start power transition of a device in a PM domain.
  * @dev: Device to start the transition of.
  *
@@ -515,6 +542,9 @@ static int pm_genpd_prepare(struct device *dev)
                 return -EBUSY;
         }
 
+        if (resume_needed(dev, genpd))
+                pm_runtime_resume(dev);
+
         genpd_acquire_lock(genpd);
 
         if (genpd->prepared_count++ == 0)