From: Ville Syrj?l? <ville.syrj...@linux.intel.com>
If a pipe is already active when we init/resume there might not be a
full modeset afterwards so drm_vblank_on() may not get called. In such
a case if someone is holding a vblank reference across a suspend/resume
cycle drm_vblank_get() called after resuming won't re-enable the vblank
interrupts.
So in order to make sure vblank interrupts get re-enabled post-resume,
call drm_vblank_on() in intel_sanitize_crtc() if the crtc is already
active.
v2: Also drm_vblank_off() if the pipe got disabled magically
Signed-off-by: Ville Syrj?l? <ville.syrjala at linux.intel.com>
---
drivers/gpu/drm/i915/intel_display.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/drivers/gpu/drm/i915/intel_display.c
b/drivers/gpu/drm/i915/intel_display.c
index 9420f4f..2e9f0b0 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -11708,6 +11708,12 @@ static void intel_sanitize_crtc(struct intel_crtc
*crtc)
reg = PIPECONF(crtc->config.cpu_transcoder);
I915_WRITE(reg, I915_READ(reg) & ~PIPECONF_FRAME_START_DELAY_MASK);
+ /* restore vblank interrupts to correct state */
+ if (crtc->active)
+ drm_vblank_on(dev, crtc->pipe);
+ else
+ drm_vblank_off(dev, crtc->pipe);
+
/* We need to sanitize the plane -> pipe mapping first because this will
* disable the crtc (and hence change the state) if it is wrong. Note
* that gen4+ has a fixed plane -> pipe mapping. */
--
1.8.5.5
