From fd237647cd2cc602cfeec2b755d517b1bf015707 Mon Sep 17 00:00:00 2001
From: Fangzhi Zuo <Jerry.Zuo@amd.com>
Date: Sun, 23 Jan 2022 13:20:07 -0500
Subject: drm/amd/display: Retrieve MST Downstream Port Status
Git-commit: 09db246ceef70bc6bd9c3e0d02b3c855f8fc25fb
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
Determine if DFP present and the type of downstream device
based on dsc_aux
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Reviewed-by: Hersen Wu <hersenxs.wu@amd.com>
Acked-by: Rodrigo Siqueira <Rodrigo.Siqueira@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>
---
.../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h | 1 +
.../display/amdgpu_dm/amdgpu_dm_mst_types.c | 23 +++++++++++++++++++
2 files changed, 24 insertions(+)
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h
index bee806ae3e52..28a2b9d476b4 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h
@@ -604,6 +604,7 @@ struct amdgpu_dm_connector {
#endif
bool force_yuv420_output;
struct dsc_preferred_settings dsc_settings;
+ union dp_downstream_port_present mst_downstream_port_present;
/* Cached display modes */
struct drm_display_mode freesync_vid_base;
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c
index 369cd15cd2d7..d24be9fb5845 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c
@@ -209,6 +209,25 @@ static bool validate_dsc_caps_on_connector(struct amdgpu_dm_connector *aconnecto
return true;
}
+
+bool retrieve_downstream_port_device(struct amdgpu_dm_connector *aconnector)
+{
+ union dp_downstream_port_present ds_port_present;
+
+ if (!aconnector->dsc_aux)
+ return false;
+
+ if (drm_dp_dpcd_read(aconnector->dsc_aux, DP_DOWNSTREAMPORT_PRESENT, &ds_port_present, 1) < 0) {
+ DRM_INFO("Failed to read downstream_port_present 0x05 from DFP of branch device\n");
+ return false;
+ }
+
+ aconnector->mst_downstream_port_present = ds_port_present;
+ DRM_INFO("Downstream port present %d, type %d\n",
+ ds_port_present.fields.PORT_PRESENT, ds_port_present.fields.PORT_TYPE);
+
+ return true;
+}
#endif
static int dm_dp_mst_get_modes(struct drm_connector *connector)
@@ -289,6 +308,10 @@ static int dm_dp_mst_get_modes(struct drm_connector *connector)
if (!validate_dsc_caps_on_connector(aconnector))
memset(&aconnector->dc_sink->dsc_caps,
0, sizeof(aconnector->dc_sink->dsc_caps));
+
+ if (!retrieve_downstream_port_device(aconnector))
+ memset(&aconnector->mst_downstream_port_present,
+ 0, sizeof(aconnector->mst_downstream_port_present));
#endif
}
}
--
2.38.1