PM: Prevent runtime suspend during system resume

[karo-tx-linux.git] / drivers / base / power / main.c

diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c
index 2700f2e4066fdd17d97fe45efdb0ba7c0ead72b8..077b9756fd8fd5580714bad627634467030bd3bb 100644 (file)
--- a/drivers/base/power/main.c
+++ b/drivers/base/power/main.c
@@ -565,7 +565,6 @@ static int device_resume(struct device *dev, pm_message_t state, bool async)
        pm_callback_t callback = NULL;
        char *info = NULL;
        int error = 0;
-       bool put = false;
 
        TRACE_DEVICE(dev);
        TRACE_RESUME(0);
@@ -583,7 +582,6 @@ static int device_resume(struct device *dev, pm_message_t state, bool async)
                goto Unlock;
 
        pm_runtime_enable(dev);
-       put = true;
 
        if (dev->pm_domain) {
                info = "power domain ";
@@ -636,9 +634,6 @@ static int device_resume(struct device *dev, pm_message_t state, bool async)
 
        TRACE_RESUME(error);
 
-       if (put)
-               pm_runtime_put_sync(dev);
-
        return error;
 }
 
@@ -749,6 +744,8 @@ static void device_complete(struct device *dev, pm_message_t state)
        }
 
        device_unlock(dev);
+
+       pm_runtime_put_sync(dev);
 }
 
 /**
@@ -1043,12 +1040,16 @@ static int __device_suspend(struct device *dev, pm_message_t state, bool async)
        if (async_error)
                goto Complete;
 
-       pm_runtime_get_noresume(dev);
+       /*
+        * If a device configured to wake up the system from sleep states
+        * has been suspended at run time and there's a resume request pending
+        * for it, this is equivalent to the device signaling wakeup, so the
+        * system suspend operation should be aborted.
+        */
        if (pm_runtime_barrier(dev) && device_may_wakeup(dev))
                pm_wakeup_event(dev, 0);
 
        if (pm_wakeup_pending()) {
-               pm_runtime_put_sync(dev);
                async_error = -EBUSY;
                goto Complete;
        }
@@ -1111,12 +1112,10 @@ static int __device_suspend(struct device *dev, pm_message_t state, bool async)
  Complete:
        complete_all(&dev->power.completion);
 
-       if (error) {
-               pm_runtime_put_sync(dev);
+       if (error)
                async_error = error;
-       } else if (dev->power.is_suspended) {
+       else if (dev->power.is_suspended)
                __pm_runtime_disable(dev, false);
-       }
 
        return error;
 }
@@ -1209,6 +1208,14 @@ static int device_prepare(struct device *dev, pm_message_t state)
        char *info = NULL;
        int error = 0;
 
+       /*
+        * If a device's parent goes into runtime suspend at the wrong time,
+        * it won't be possible to resume the device.  To prevent this we
+        * block runtime suspend here, during the prepare phase, and allow
+        * it again during the complete phase.
+        */
+       pm_runtime_get_noresume(dev);
+
        device_lock(dev);
 
        dev->power.wakeup_path = device_may_wakeup(dev);