From 81055854d096959898fdc17ed11729eb019eff07 Mon Sep 17 00:00:00 2001 From: Adam Jackson Date: Thu, 21 Jul 2011 17:48:37 -0400 Subject: [PATCH] drm/i915/dp: Explicitly disable symbol scrambling while training The DP spec says training patterns 1 and 2 are to be sent non-scrambled, and the GPU docs claim that happens (or at least, there's no explicit scrambling control). But the sink may be confused if we don't explicitly tell it what we're doing, so play it safe. Signed-off-by: Adam Jackson Reviewed-by: Jesse Barnes Signed-off-by: Keith Packard --- drivers/gpu/drm/i915/intel_dp.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c index 1c3a36feaf69..8aecb072466b 100644 --- a/drivers/gpu/drm/i915/intel_dp.c +++ b/drivers/gpu/drm/i915/intel_dp.c @@ -1370,7 +1370,8 @@ intel_dp_start_link_train(struct intel_dp *intel_dp) reg = DP | DP_LINK_TRAIN_PAT_1; if (!intel_dp_set_link_train(intel_dp, reg, - DP_TRAINING_PATTERN_1)) + DP_TRAINING_PATTERN_1 | + DP_LINK_SCRAMBLING_DISABLE)) break; /* Set training pattern 1 */ @@ -1445,7 +1446,8 @@ intel_dp_complete_link_train(struct intel_dp *intel_dp) /* channel eq pattern */ if (!intel_dp_set_link_train(intel_dp, reg, - DP_TRAINING_PATTERN_2)) + DP_TRAINING_PATTERN_2 | + DP_LINK_SCRAMBLING_DISABLE)) break; udelay(400); -- 2.20.1