drm/amd/display: Fix dongle_caps containing stale information.

[WHY]

During detection:
function: get_active_converter_info populates link->dpcd_caps.dongle_caps
only when dpcd_rev >= DPCD_REV_11 and DWN_STRM_PORTX_TYPE is
DOWN_STREAM_DETAILED_HDMI or DOWN_STREAM_DETAILED_DP_PLUS_PLUS.
Otherwise, it is not cleared, and stale information remains.

During mode validation:
function: dp_active_dongle_validate_timing reads
link->dpcd_caps.dongle_caps->dongle_type to determine the maximum
pixel clock to support. This information is now stale and no longer
valid.

[HOW]
dp_active_dongle_validate_timing should be using
link->dpcd_caps->dongle_type instead.

Signed-off-by: David Galiffi <david.galiffi@amd.com>
Reviewed-by: Jun Lei <Jun.Lei@amd.com>
Acked-by: Bhawanpreet Lakha <Bhawanpreet.Lakha@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 46c4fff..25bce56 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/core/dc_link.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
@@ -2256,7 +2256,7 @@ static bool dp_active_dongle_validate_timing(
                break;
        }
 
-       if (dongle_caps->dongle_type != DISPLAY_DONGLE_DP_HDMI_CONVERTER ||
+       if (dpcd_caps->dongle_type != DISPLAY_DONGLE_DP_HDMI_CONVERTER ||
                dongle_caps->extendedCapValid == false)
                return true;
 

diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c b/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c
index aae2041..0f59b68 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c
@@ -2575,6 +2575,7 @@ static void get_active_converter_info(
        uint8_t data, struct dc_link *link)
 {
        union dp_downstream_port_present ds_port = { .byte = data };
+       memset(&link->dpcd_caps.dongle_caps, 0, sizeof(link->dpcd_caps.dongle_caps));
 
        /* decode converter info*/
        if (!ds_port.fields.PORT_PRESENT) {