From 06319a343a73879c801f0df8a3cc48c1195b531d Mon Sep 17 00:00:00 2001
From: Harry VanZyllDeJong <hvanzyll@amd.com>
Date: Tue, 11 Jan 2022 15:11:42 -0500
Subject: drm/amd/display: Fix crash on setting VRR with no display connected
Git-commit: da8c25929b78b39438eb62b87e213c45dfad6038
Patch-mainline: v5.19-rc1
References: jsc#PED-1166 jsc#PED-1168 jsc#PED-1170 jsc#PED-1218 jsc#PED-1220 jsc#PED-1222 jsc#PED-1223 jsc#PED-1225

[HOW&WHY]
VRR was getting set at the same time
the timing generator would be null when there was no display
connected. Added null check to the timing generator variable
so it does not get referenced if it is null.

Reviewed-by: Harry Vanzylldejong <harry.vanzylldejong@amd.com>
Reviewed-by: Evgenii Krasnikov <Evgenii.Krasnikov@amd.com>
Reviewed-by: Nicholas Choi <Nicholas.Choi@amd.com>
Acked-by: Pavle Kotarac <Pavle.Kotarac@amd.com>
Signed-off-by: Harry VanZyllDeJong <hvanzyll@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
 .../amd/display/dc/dcn10/dcn10_hw_sequencer.c    | 16 ++++++++++------
 1 file changed, 10 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c
index c84011caa73c..6c69fd3bc77a 100644
--- a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c
+++ b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c
@@ -3053,12 +3053,16 @@ void dcn10_set_drr(struct pipe_ctx **pipe_ctx,
 	 * as well.
 	 */
 	for (i = 0; i < num_pipes; i++) {
-		pipe_ctx[i]->stream_res.tg->funcs->set_drr(
-			pipe_ctx[i]->stream_res.tg, &params);
-		if (adjust.v_total_max != 0 && adjust.v_total_min != 0)
-			pipe_ctx[i]->stream_res.tg->funcs->set_static_screen_control(
-					pipe_ctx[i]->stream_res.tg,
-					event_triggers, num_frames);
+		if ((pipe_ctx[i]->stream_res.tg != NULL) && pipe_ctx[i]->stream_res.tg->funcs) {
+			if (pipe_ctx[i]->stream_res.tg->funcs->set_drr)
+				pipe_ctx[i]->stream_res.tg->funcs->set_drr(
+					pipe_ctx[i]->stream_res.tg, &params);
+			if (adjust.v_total_max != 0 && adjust.v_total_min != 0)
+				if (pipe_ctx[i]->stream_res.tg->funcs->set_static_screen_control)
+					pipe_ctx[i]->stream_res.tg->funcs->set_static_screen_control(
+						pipe_ctx[i]->stream_res.tg,
+						event_triggers, num_frames);
+		}
 	}
 }
 
-- 
2.38.1