drm/i915: Force sink crc stop before start.
By Vesa DP spec, test counter at DP_TEST_SINK_MISC just reset to 0
when unsetting DP_TEST_SINK_START, so let's force this stop here.
But let's minimize the aux transactions and just do it when we know
it hasn't been properly stoped.
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Rafael Antognolli <rafael.antognolli@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 016e7bc..1f7cc40 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -3995,22 +3995,30 @@
return intel_dp->is_mst;
}
-static void intel_dp_sink_crc_stop(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 intel_crtc *intel_crtc = to_intel_crtc(dig_port->base.base.crtc);
u8 buf;
+ int ret = 0;
if (drm_dp_dpcd_readb(&intel_dp->aux, DP_TEST_SINK, &buf) < 0) {
DRM_DEBUG_KMS("Sink CRC couldn't be stopped properly\n");
- return;
+ ret = -EIO;
+ goto out;
}
if (drm_dp_dpcd_writeb(&intel_dp->aux, DP_TEST_SINK,
- buf & ~DP_TEST_SINK_START) < 0)
+ buf & ~DP_TEST_SINK_START) < 0) {
DRM_DEBUG_KMS("Sink CRC couldn't be stopped properly\n");
+ ret = -EIO;
+ goto out;
+ }
+ intel_dp->sink_crc_started = false;
+ out:
hsw_enable_ips(intel_crtc);
+ return ret;
}
static int intel_dp_sink_crc_start(struct intel_dp *intel_dp)
@@ -4018,6 +4026,13 @@
struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
struct intel_crtc *intel_crtc = to_intel_crtc(dig_port->base.base.crtc);
u8 buf;
+ int ret;
+
+ if (intel_dp->sink_crc_started) {
+ ret = intel_dp_sink_crc_stop(intel_dp);
+ if (ret)
+ return ret;
+ }
if (drm_dp_dpcd_readb(&intel_dp->aux, DP_TEST_SINK_MISC, &buf) < 0)
return -EIO;
@@ -4036,6 +4051,7 @@
return -EIO;
}
+ intel_dp->sink_crc_started = true;
return 0;
}