FAILED: patch "[PATCH] drm/amd/display: Keep disable aux-i delay as 0" failed to apply to 6.4-stable tree

[<gregkh@linuxfoundation.org>]

The patch below does not apply to the 6.4-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.4.y
git checkout FETCH_HEAD
git cherry-pick -x 5a096b73c8fed3a9987ba15378285df360e2284b
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2023072126-foil-stardust-93cf@gregkh' --subject-prefix 'PATCH 6.4.y' HEAD^..

Possible dependencies:



thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 5a096b73c8fed3a9987ba15378285df360e2284b Mon Sep 17 00:00:00 2001
From: Michael Strauss <michael.strauss@amd.com>
Date: Tue, 11 Apr 2023 12:44:54 -0400
Subject: [PATCH] drm/amd/display: Keep disable aux-i delay as 0

[WHY]
Current Aux-I sequence checks for local_sink which isn't populated on
MST links

[HOW]
Leave disable aux-i delay as 0 for MST cases

Cc: stable@vger.kernel.org
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Reviewed-by: George Shen <George.Shen@amd.com>
Reviewed-by: Aric Cyr <Aric.Cyr@amd.com>
Acked-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Michael Strauss <michael.strauss@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_training_fixed_vs_pe_retimer.c b/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_training_fixed_vs_pe_retimer.c
index fb6c938c6dab..15faaf645b14 100644
--- a/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_training_fixed_vs_pe_retimer.c
+++ b/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_training_fixed_vs_pe_retimer.c
@@ -233,8 +233,7 @@ enum link_training_result dp_perform_fixed_vs_pe_training_sequence_legacy(
 			link->dpcd_caps.lttpr_caps.phy_repeater_cnt);
 	const uint8_t vendor_lttpr_write_data_intercept_en[4] = {0x1, 0x55, 0x63, 0x0};
 	const uint8_t vendor_lttpr_write_data_intercept_dis[4] = {0x1, 0x55, 0x63, 0x68};
-	uint32_t pre_disable_intercept_delay_ms =
-			link->local_sink->edid_caps.panel_patch.delay_disable_aux_intercept_ms;
+	uint32_t pre_disable_intercept_delay_ms = 0;
 	uint8_t vendor_lttpr_write_data_vs[4] = {0x1, 0x51, 0x63, 0x0};
 	uint8_t vendor_lttpr_write_data_pe[4] = {0x1, 0x52, 0x63, 0x0};
 	uint32_t vendor_lttpr_write_address = 0xF004F;
@@ -245,6 +244,10 @@ enum link_training_result dp_perform_fixed_vs_pe_training_sequence_legacy(
 	uint8_t toggle_rate;
 	uint8_t rate;
 
+	if (link->local_sink)
+		pre_disable_intercept_delay_ms =
+				link->local_sink->edid_caps.panel_patch.delay_disable_aux_intercept_ms;
+
 	/* Only 8b/10b is supported */
 	ASSERT(link_dp_get_encoding_format(&lt_settings->link_settings) ==
 			DP_8b_10b_ENCODING);
@@ -595,10 +598,7 @@ enum link_training_result dp_perform_fixed_vs_pe_training_sequence(
 	const uint8_t vendor_lttpr_write_data_adicora_eq3[4] = {0x1, 0x55, 0x63, 0x68};
 	uint8_t vendor_lttpr_write_data_vs[4] = {0x1, 0x51, 0x63, 0x0};
 	uint8_t vendor_lttpr_write_data_pe[4] = {0x1, 0x52, 0x63, 0x0};
-	uint32_t pre_disable_intercept_delay_ms =
-			link->local_sink->edid_caps.panel_patch.delay_disable_aux_intercept_ms;
-
-
+	uint32_t pre_disable_intercept_delay_ms = 0;
 	uint32_t vendor_lttpr_write_address = 0xF004F;
 	enum link_training_result status = LINK_TRAINING_SUCCESS;
 	uint8_t lane = 0;
@@ -607,6 +607,10 @@ enum link_training_result dp_perform_fixed_vs_pe_training_sequence(
 	uint8_t toggle_rate;
 	uint8_t rate;
 
+	if (link->local_sink)
+		pre_disable_intercept_delay_ms =
+				link->local_sink->edid_caps.panel_patch.delay_disable_aux_intercept_ms;
+
 	/* Only 8b/10b is supported */
 	ASSERT(link_dp_get_encoding_format(&lt_settings->link_settings) ==
 			DP_8b_10b_ENCODING);