Commit c28d1484 authored May 28, 2019 by Tomi Valkeinen Committed by Andrzej Hajda May 31, 2019

drm/bridge: tc358767: reset voltage-swing & pre-emphasis



We need to reset DPCD voltage-swing & pre-emphasis before starting the
link training, as otherwise tc358767 will use the previous values as
minimums.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Reviewed-by: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190528082747.3631-3-tomi.valkeinen@ti.com

parent bfb6e014

drivers/gpu/drm/bridge/tc358767.c

+7 −0

Original line number	Diff line number	Diff line
		@@ -956,6 +956,13 @@ static int tc_main_link_setup(struct tc_data *tc)
		if (ret < 0)
		goto err_dpcd_write;

		/* Reset voltage-swing & pre-emphasis */
		tmp[0] = tmp[1] = DP_TRAIN_VOLTAGE_SWING_LEVEL_0 \|
		DP_TRAIN_PRE_EMPH_LEVEL_0;
		ret = drm_dp_dpcd_write(aux, DP_TRAINING_LANE0_SET, tmp, 2);
		if (ret < 0)
		goto err_dpcd_write;

		ret = tc_link_training(tc, DP_TRAINING_PATTERN_1);
		if (ret)
		goto err;

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