From: Rodrigo Vivi Date: Thu, 5 Nov 2015 18:50:19 +0000 (-0800) Subject: drm/i915: Allow 1 vblank to let Sink CRC calculation to start or stop. X-Git-Tag: v4.5-rc1~74^2~37^2~44 X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=d72f9d919a60e5096105237a72f046b7a20fb53f;p=karo-tx-linux.git drm/i915: Allow 1 vblank to let Sink CRC calculation to start or stop. According to VESA DP Spec, setting TEST_SINK_START (bit 0) of TEST_SINK (00270h) "Stop/Start calculating CRC on the next frame" So let's wait at least 1 vblank to really say the calculation stopped or started. Signed-off-by: Rodrigo Vivi Reviewed-by: Paulo Zanoni Signed-off-by: Daniel Vetter --- diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c index 9d90bc966533..3ffedd897fff 100644 --- a/drivers/gpu/drm/i915/intel_dp.c +++ b/drivers/gpu/drm/i915/intel_dp.c @@ -3949,6 +3949,7 @@ intel_dp_probe_mst(struct intel_dp *intel_dp) static int intel_dp_sink_crc_stop(struct intel_dp *intel_dp) { struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp); + struct drm_device *dev = dig_port->base.base.dev; struct intel_crtc *intel_crtc = to_intel_crtc(dig_port->base.base.crtc); u8 buf; int ret = 0; @@ -3966,6 +3967,7 @@ static int intel_dp_sink_crc_stop(struct intel_dp *intel_dp) goto out; } + intel_wait_for_vblank(dev, intel_crtc->pipe); intel_dp->sink_crc.started = false; out: hsw_enable_ips(intel_crtc); @@ -3975,6 +3977,7 @@ static int intel_dp_sink_crc_stop(struct intel_dp *intel_dp) static int intel_dp_sink_crc_start(struct intel_dp *intel_dp) { struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp); + struct drm_device *dev = dig_port->base.base.dev; struct intel_crtc *intel_crtc = to_intel_crtc(dig_port->base.base.crtc); u8 buf; int ret; @@ -4004,6 +4007,7 @@ static int intel_dp_sink_crc_start(struct intel_dp *intel_dp) return -EIO; } + intel_wait_for_vblank(dev, intel_crtc->pipe); intel_dp->sink_crc.started = true; return 0; }