[PATCH 3/3] drm/i915: Use drm_vblank_on() to re-enable vblank interrupts

[ville.syrjala at linux.intel.com]

From: Ville Syrjälä <ville.syrjala at linux.intel.com>

Sprinkle drm_vblank_on() calls to the .crtc_enable() callbacks.
Also drop the drm_vblank_{pre,post}_modeset() calls since those
are now useless.

Testcase: igt/kms_flip/{dpms,modeset}-vs-vblank-race
Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
---
 drivers/gpu/drm/i915/intel_display.c | 13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 7e8bfd8..87895dd 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -3612,6 +3612,8 @@ static void ironlake_crtc_enable(struct drm_crtc *crtc)
 	 * happening.
 	 */
 	intel_wait_for_vblank(dev, intel_crtc->pipe);
+
+	drm_vblank_on(dev, pipe);
 }
 
 /* IPS only exists on ULT machines and is tied to pipe A. */
@@ -3637,6 +3639,8 @@ static void haswell_crtc_enable_planes(struct drm_crtc *crtc)
 	mutex_lock(&dev->struct_mutex);
 	intel_update_fbc(dev);
 	mutex_unlock(&dev->struct_mutex);
+
+	drm_vblank_on(dev, pipe);
 }
 
 static void haswell_crtc_disable_planes(struct drm_crtc *crtc)
@@ -4235,6 +4239,8 @@ static void valleyview_crtc_enable(struct drm_crtc *crtc)
 
 	for_each_encoder_on_crtc(dev, crtc, encoder)
 		encoder->enable(encoder);
+
+	drm_vblank_on(dev, pipe);
 }
 
 static void i9xx_crtc_enable(struct drm_crtc *crtc)
@@ -4280,6 +4286,8 @@ static void i9xx_crtc_enable(struct drm_crtc *crtc)
 
 	for_each_encoder_on_crtc(dev, crtc, encoder)
 		encoder->enable(encoder);
+
+	drm_vblank_on(dev, pipe);
 }
 
 static void i9xx_pfit_disable(struct intel_crtc *crtc)
@@ -7014,15 +7022,10 @@ static int intel_crtc_mode_set(struct drm_crtc *crtc,
 	struct intel_encoder *encoder;
 	struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
 	struct drm_display_mode *mode = &intel_crtc->config.requested_mode;
-	int pipe = intel_crtc->pipe;
 	int ret;
 
-	drm_vblank_pre_modeset(dev, pipe);
-
 	ret = dev_priv->display.crtc_mode_set(crtc, x, y, fb);
 
-	drm_vblank_post_modeset(dev, pipe);
-
 	if (ret != 0)
 		return ret;
 
-- 
1.8.3.2