drm/radeon/kms: switch to condition waiting for reclocking

We tried to implement interruptible waiting with timeout (it was broken
anyway) which was not a good idea as explained by Andrew. It's possible
to avoid using additional variable but actually it inroduces using more
complex in-kernel tools. So simply add one variable for condition.

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/radeon/r100.c b/drivers/gpu/drm/radeon/r100.c
index 91eb762..73f9a79 100644
--- a/drivers/gpu/drm/radeon/r100.c
+++ b/drivers/gpu/drm/radeon/r100.c
@@ -312,10 +312,12 @@
 		/* Vertical blank interrupts */
 		if (status & RADEON_CRTC_VBLANK_STAT) {
 			drm_handle_vblank(rdev->ddev, 0);
+			rdev->pm.vblank_sync = true;
 			wake_up(&rdev->irq.vblank_queue);
 		}
 		if (status & RADEON_CRTC2_VBLANK_STAT) {
 			drm_handle_vblank(rdev->ddev, 1);
+			rdev->pm.vblank_sync = true;
 			wake_up(&rdev->irq.vblank_queue);
 		}
 		if (status & RADEON_FP_DETECT_STAT) {
diff --git a/drivers/gpu/drm/radeon/r600.c b/drivers/gpu/drm/radeon/r600.c
index c522901..5b56a1b 100644
--- a/drivers/gpu/drm/radeon/r600.c
+++ b/drivers/gpu/drm/radeon/r600.c
@@ -2765,6 +2765,7 @@
 			case 0: /* D1 vblank */
 				if (disp_int & LB_D1_VBLANK_INTERRUPT) {
 					drm_handle_vblank(rdev->ddev, 0);
+					rdev->pm.vblank_sync = true;
 					wake_up(&rdev->irq.vblank_queue);
 					disp_int &= ~LB_D1_VBLANK_INTERRUPT;
 					DRM_DEBUG("IH: D1 vblank\n");
@@ -2786,6 +2787,7 @@
 			case 0: /* D2 vblank */
 				if (disp_int & LB_D2_VBLANK_INTERRUPT) {
 					drm_handle_vblank(rdev->ddev, 1);
+					rdev->pm.vblank_sync = true;
 					wake_up(&rdev->irq.vblank_queue);
 					disp_int &= ~LB_D2_VBLANK_INTERRUPT;
 					DRM_DEBUG("IH: D2 vblank\n");
diff --git a/drivers/gpu/drm/radeon/radeon.h b/drivers/gpu/drm/radeon/radeon.h
index ba93e5a..b54d4f3 100644
--- a/drivers/gpu/drm/radeon/radeon.h
+++ b/drivers/gpu/drm/radeon/radeon.h
@@ -687,6 +687,7 @@
 	bool 			downclocked;
 	int			active_crtcs;
 	int			req_vblank;
+	bool			vblank_sync;
 	fixed20_12		max_bandwidth;
 	fixed20_12		igp_sideport_mclk;
 	fixed20_12		igp_system_mclk;
diff --git a/drivers/gpu/drm/radeon/radeon_pm.c b/drivers/gpu/drm/radeon/radeon_pm.c
index d4d1c39..d800b86 100644
--- a/drivers/gpu/drm/radeon/radeon_pm.c
+++ b/drivers/gpu/drm/radeon/radeon_pm.c
@@ -353,10 +353,12 @@
 		rdev->pm.req_vblank |= (1 << 1);
 		drm_vblank_get(rdev->ddev, 1);
 	}
-	if (rdev->pm.active_crtcs)
-		wait_event_interruptible_timeout(
-			rdev->irq.vblank_queue, 0,
+	if (rdev->pm.active_crtcs) {
+		rdev->pm.vblank_sync = false;
+		wait_event_timeout(
+			rdev->irq.vblank_queue, rdev->pm.vblank_sync,
 			msecs_to_jiffies(RADEON_WAIT_VBLANK_TIMEOUT));
+	}
 	if (rdev->pm.req_vblank & (1 << 0)) {
 		rdev->pm.req_vblank &= ~(1 << 0);
 		drm_vblank_put(rdev->ddev, 0);
diff --git a/drivers/gpu/drm/radeon/rs600.c b/drivers/gpu/drm/radeon/rs600.c
index 47f046b..ac7c27a 100644
--- a/drivers/gpu/drm/radeon/rs600.c
+++ b/drivers/gpu/drm/radeon/rs600.c
@@ -392,10 +392,12 @@
 		/* Vertical blank interrupts */
 		if (G_007EDC_LB_D1_VBLANK_INTERRUPT(r500_disp_int)) {
 			drm_handle_vblank(rdev->ddev, 0);
+			rdev->pm.vblank_sync = true;
 			wake_up(&rdev->irq.vblank_queue);
 		}
 		if (G_007EDC_LB_D2_VBLANK_INTERRUPT(r500_disp_int)) {
 			drm_handle_vblank(rdev->ddev, 1);
+			rdev->pm.vblank_sync = true;
 			wake_up(&rdev->irq.vblank_queue);
 		}
 		if (G_007EDC_DC_HOT_PLUG_DETECT1_INTERRUPT(r500_disp_int)) {