drm/amd/display: To prevent detecting new sink from spurious HPD

Signed-off-by: Martin Tsai <martin.tsai@amd.com>
Reviewed-by: Tony Cheng <Tony.Cheng@amd.com>
Acked-by: Harry Wentland <Harry.Wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link.c b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
index 4a70948c91b1d1f8123166a65837cefae2327193..ee23b609d7dd3bf18e57943a2cfa4e624774ded6 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/core/dc_link.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
@@ -565,8 +565,6 @@ bool dc_link_detect(struct dc_link *link, enum dc_detect_reason reason)
                        link->local_sink)
                return true;
 
-       link_disconnect_sink(link);
-
        if (new_connection_type != dc_connection_none) {
                link->type = new_connection_type;
 
@@ -638,8 +636,8 @@ bool dc_link_detect(struct dc_link *link, enum dc_detect_reason reason)
                if (link->dpcd_caps.sink_count.bits.SINK_COUNT)
                        link->dpcd_sink_count = link->dpcd_caps.sink_count.
                                        bits.SINK_COUNT;
-                       else
-                               link->dpcd_sink_count = 1;
+               else
+                       link->dpcd_sink_count = 1;
 
                dal_ddc_service_set_transaction_type(
                                                link->ddc,
@@ -651,16 +649,24 @@ bool dc_link_detect(struct dc_link *link, enum dc_detect_reason reason)
                sink_init_data.link = link;
                sink_init_data.sink_signal = sink_caps.signal;
 
-               sink = dc_sink_create(&sink_init_data);
-               if (!sink) {
-                       DC_ERROR("Failed to create sink!\n");
-                       return false;
-               }
+               if (link->local_sink)   {
+                       sink = link->local_sink;
+               } else {
+                       link_disconnect_sink(link);
+
+                       sink_init_data.link = link;
+                       sink_init_data.sink_signal = sink_caps.signal;
 
-               sink->dongle_max_pix_clk = sink_caps.max_hdmi_pixel_clock;
-               sink->converter_disable_audio = converter_disable_audio;
+                       sink = dc_sink_create(&sink_init_data);
+                       if (!sink) {
+                               DC_ERROR("Failed to create sink!\n");
+                               return false;
+                       }
+                       sink->dongle_max_pix_clk = sink_caps.max_hdmi_pixel_clock;
+                       sink->converter_disable_audio = converter_disable_audio;
 
-               link->local_sink = sink;
+                       link->local_sink = sink;
+               }
 
                edid_status = dm_helpers_read_local_edid(
                                link->ctx,
@@ -752,8 +758,22 @@ bool dc_link_detect(struct dc_link *link, enum dc_detect_reason reason)
                        memset(link->mst_stream_alloc_table.stream_allocations, 0, sizeof(link->mst_stream_alloc_table.stream_allocations));
                }
 
-               link->type = dc_connection_none;
-               sink_caps.signal = SIGNAL_TYPE_NONE;
+               if (link->local_sink) {
+                       sink = link->local_sink;
+                       edid_status = dm_helpers_read_local_edid(
+                                               link->ctx,
+                                               link,
+                                               sink);
+                       if (edid_status != EDID_OK) {
+                               link_disconnect_sink(link);
+                               link->type = dc_connection_none;
+                               sink_caps.signal = SIGNAL_TYPE_NONE;
+                       }
+               } else {
+                       link_disconnect_sink(link);
+                       link->type = dc_connection_none;
+                       sink_caps.signal = SIGNAL_TYPE_NONE;
+               }
        }
 
        LINK_INFO("link=%d, dc_sink_in=%p is now %s\n",