From da4dd48e996dd90ddbcdace11fc76dcb6a384866 Mon Sep 17 00:00:00 2001
From: Fangzhi Zuo <Jerry.Zuo@amd.com>
Date: Fri, 28 Jan 2022 22:04:10 +0800
Subject: drm/amd/display: Trigger DP2 Sequence With Uncertified Cable
Git-commit: bd682a788c1f4fbefe17b3ee9e0e3debdefeec6d
Patch-mainline: v5.18-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

DP2 sequence is triggered only if VESA certified cable is detected.

Force DP2 sequence with uncertified cable for testing purpose.

Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Reviewed-by: Wenjing Liu <Wenjing.Liu@amd.com>
Acked-by: Stylon Wang <stylon.wang@amd.com>
Signed-off-by: Fangzhi Zuo <Jerry.Zuo@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
 .../amd/display/amdgpu_dm/amdgpu_dm_debugfs.c | 26 +++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c
index aca725874bcf..bdea177fae55 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c
@@ -3431,6 +3431,30 @@ static int dp_force_sst_get(void *data, u64 *val)
 }
 DEFINE_DEBUGFS_ATTRIBUTE(dp_set_mst_en_for_sst_ops, dp_force_sst_get,
 			 dp_force_sst_set, "%llu\n");
+
+/*
+ * Force DP2 sequence without VESA certified cable.
+ * Example usage: echo 1 > /sys/kernel/debug/dri/0/amdgpu_dm_dp_ignore_cable_id
+ */
+static int dp_ignore_cable_id_set(void *data, u64 val)
+{
+	struct amdgpu_device *adev = data;
+
+	adev->dm.dc->debug.ignore_cable_id = val;
+
+	return 0;
+}
+
+static int dp_ignore_cable_id_get(void *data, u64 *val)
+{
+	struct amdgpu_device *adev = data;
+
+	*val = adev->dm.dc->debug.ignore_cable_id;
+
+	return 0;
+}
+DEFINE_DEBUGFS_ATTRIBUTE(dp_ignore_cable_id_ops, dp_ignore_cable_id_get,
+			 dp_ignore_cable_id_set, "%llu\n");
 #endif
 
 /*
@@ -3549,6 +3573,8 @@ void dtn_debugfs_init(struct amdgpu_device *adev)
 #if defined(CONFIG_DRM_AMD_DC_DCN)
 	debugfs_create_file("amdgpu_dm_dp_set_mst_en_for_sst", 0644, root, adev,
 				&dp_set_mst_en_for_sst_ops);
+	debugfs_create_file("amdgpu_dm_dp_ignore_cable_id", 0644, root, adev,
+				&dp_ignore_cable_id_ops);
 #endif
 
 	debugfs_create_file_unsafe("amdgpu_dm_visual_confirm", 0644, root, adev,
-- 
2.38.1