3 files changed, 28 insertions, 8 deletions

diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c
index 6b3ce6d38848..7998ee66b317 100644
--- a/drivers/gpu/drm/drm_irq.c
+++ b/drivers/gpu/drm/drm_irq.c
@@ -429,15 +429,21 @@ int drm_vblank_get(struct drm_device *dev, int crtc)
 
         spin_lock_irqsave(&dev->vbl_lock, irqflags);
         /* Going from 0->1 means we have to enable interrupts again */
-        if (atomic_add_return(1, &dev->vblank_refcount[crtc]) == 1 &&
-            !dev->vblank_enabled[crtc]) {
-                ret = dev->driver->enable_vblank(dev, crtc);
-                DRM_DEBUG("enabling vblank on crtc %d, ret: %d\n", crtc, ret);
-                if (ret)
+        if (atomic_add_return(1, &dev->vblank_refcount[crtc]) == 1) {
+                if (!dev->vblank_enabled[crtc]) {
+                        ret = dev->driver->enable_vblank(dev, crtc);
+                        DRM_DEBUG("enabling vblank on crtc %d, ret: %d\n", crtc, ret);
+                        if (ret)
+                                atomic_dec(&dev->vblank_refcount[crtc]);
+                        else {
+                                dev->vblank_enabled[crtc] = 1;
+                                drm_update_vblank_count(dev, crtc);
+                        }
+                }
+        } else {
+                if (!dev->vblank_enabled[crtc]) {
                         atomic_dec(&dev->vblank_refcount[crtc]);
-                else {
-                        dev->vblank_enabled[crtc] = 1;
-                        drm_update_vblank_count(dev, crtc);
+                        ret = -EINVAL;
                 }
         }
         spin_unlock_irqrestore(&dev->vbl_lock, irqflags);
@@ -464,6 +470,18 @@ void drm_vblank_put(struct drm_device *dev, int crtc)
 }
 EXPORT_SYMBOL(drm_vblank_put);
 
+void drm_vblank_off(struct drm_device *dev, int crtc)
+{
+        unsigned long irqflags;
+
+        spin_lock_irqsave(&dev->vbl_lock, irqflags);
+        DRM_WAKEUP(&dev->vbl_queue[crtc]);
+        dev->vblank_enabled[crtc] = 0;
+        dev->last_vblank[crtc] = dev->driver->get_vblank_counter(dev, crtc);
+        spin_unlock_irqrestore(&dev->vbl_lock, irqflags);
+}
+EXPORT_SYMBOL(drm_vblank_off);
+
 /**
  * drm_vblank_pre_modeset - account for vblanks across mode sets
  * @dev: DRM device
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 267adc6fbfc1..65b76fffd9e3 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -1924,6 +1924,7 @@ static void i9xx_crtc_dpms(struct drm_crtc *crtc, int mode)
 
                 /* Give the overlay scaler a chance to disable if it's on this pipe */
                 intel_crtc_dpms_overlay(intel_crtc, false);
+                drm_vblank_off(dev, pipe);
 
                 if (dev_priv->cfb_plane == plane &&
                     dev_priv->display.disable_fbc)
diff --git a/include/drm/drmP.h b/include/drm/drmP.h
index febf6c530c66..fd919959d146 100644
--- a/include/drm/drmP.h
+++ b/include/drm/drmP.h
@@ -1288,6 +1288,7 @@ extern u32 drm_vblank_count(struct drm_device *dev, int crtc);
 extern void drm_handle_vblank(struct drm_device *dev, int crtc);
 extern int drm_vblank_get(struct drm_device *dev, int crtc);
 extern void drm_vblank_put(struct drm_device *dev, int crtc);
+extern void drm_vblank_off(struct drm_device *dev, int crtc);
 extern void drm_vblank_cleanup(struct drm_device *dev);
 /* Modesetting support */
 extern void drm_vblank_pre_modeset(struct drm_device *dev, int crtc);