drm: Make the vblank disable timer per-crtc

Currently there's one per-device vblank disable timer, and it gets
reset wheneven the vblank refcount for any crtc drops to zero. That
means that one crtc could accidentally be keeping the vblank interrupts
for other crtcs enabled even if there are no users for them. Make the
disable timer per-crtc to avoid this issue.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/include/drm/drmP.h b/include/drm/drmP.h
index 12f10bc..9d982d4 100644
--- a/include/drm/drmP.h
+++ b/include/drm/drmP.h
@@ -1024,14 +1024,17 @@
 };
 
 struct drm_vblank_crtc {
+	struct drm_device *dev;		/* pointer to the drm_device */
 	wait_queue_head_t queue;	/**< VBLANK wait queue */
 	struct timeval time[DRM_VBLANKTIME_RBSIZE];	/**< timestamp of current count */
+	struct timer_list disable_timer;		/* delayed disable timer */
 	atomic_t count;			/**< number of VBLANK interrupts */
 	atomic_t refcount;		/* number of users of vblank interruptsper crtc */
 	u32 last;			/* protected by dev->vbl_lock, used */
 					/* for wraparound handling */
 	u32 last_wait;			/* Last vblank seqno waited per CRTC */
 	unsigned int inmodeset;		/* Display driver is setting mode */
+	int crtc;			/* crtc index */
 	bool enabled;			/* so we don't call enable more than
 					   once per disable */
 };
@@ -1119,7 +1122,6 @@
 
 	spinlock_t vblank_time_lock;    /**< Protects vblank count and time updates during vblank enable/disable */
 	spinlock_t vbl_lock;
-	struct timer_list vblank_disable_timer;
 
 	u32 max_vblank_count;           /**< size of vblank counter register */