[PATCH] Revert "drm/i915: try to train DP even harder"

From: Takashi Iwai
Date: Mon Mar 11 2013 - 13:40:27 EST


This reverts commit 0d71068835e2610576d369d6d4cbf90e0f802a71.

Not only that the commit introduces a bogus check (voltage_tries == 5
will never meet at the inserted code path), it brings the i915 driver
into an endless dp-train loop on HP Z1 desktop machine with IVY+eDP.

At least reverting this commit recovers the framebuffer (but X is
still broken by other reasons...)

Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
---
drivers/gpu/drm/i915/intel_dp.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index f61cb79..7d250aa 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -1929,7 +1929,7 @@ intel_dp_start_link_train(struct intel_dp *intel_dp)
for (i = 0; i < intel_dp->lane_count; i++)
if ((intel_dp->train_set[i] & DP_TRAIN_MAX_SWING_REACHED) == 0)
break;
- if (i == intel_dp->lane_count && voltage_tries == 5) {
+ if (i == intel_dp->lane_count) {
++loop_tries;
if (loop_tries == 5) {
DRM_DEBUG_KMS("too many full retries, give up\n");
--
1.8.1.4

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