From: Aurabindo Pillai <aurabindo.pillai@xxxxxxx>
commit 613a7956deb3b1ffa2810c6d4c90ee9c3d743dbb upstream.
Disable FAMS on a Samsung Odyssey G9 monitor. Experiments show that this
monitor does not work well under some use cases, and is likely
implementation specific bug on the monitor's firmware.
Cc: stable@xxxxxxxxxxxxxxx
Reviewed-by: Rodrigo Siqueira <rodrigo.siqueira@xxxxxxx>
Signed-off-by: Aurabindo Pillai <aurabindo.pillai@xxxxxxx>
Tested-by: Daniel Wheeler <daniel.wheeler@xxxxxxx>
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c | 26 ++++++++++++++
1 file changed, 26 insertions(+)
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
@@ -42,6 +42,30 @@
#include "dm_helpers.h"
#include "ddc_service_types.h"
+static u32 edid_extract_panel_id(struct edid *edid)
+{
+ return (u32)edid->mfg_id[0] << 24 |
+ (u32)edid->mfg_id[1] << 16 |
+ (u32)EDID_PRODUCT_ID(edid);
+}
+
+static void apply_edid_quirks(struct edid *edid, struct dc_edid_caps *edid_caps)
+{
+ uint32_t panel_id = edid_extract_panel_id(edid);
+
+ switch (panel_id) {
+ /* Workaround for some monitors which does not work well with FAMS */
+ case drm_edid_encode_panel_id('S', 'A', 'M', 0x0E5E):
+ case drm_edid_encode_panel_id('S', 'A', 'M', 0x7053):
+ case drm_edid_encode_panel_id('S', 'A', 'M', 0x71AC):
+ DRM_DEBUG_DRIVER("Disabling FAMS on monitor with panel id %X\n", panel_id);
+ edid_caps->panel_patch.disable_fams = true;
+ break;
+ default:
+ return;
+ }
+}
+
/* dm_helpers_parse_edid_caps
*
* Parse edid caps
@@ -113,6 +137,8 @@ enum dc_edid_status dm_helpers_parse_edi
else
edid_caps->speaker_flags = DEFAULT_SPEAKER_LOCATION;
+ apply_edid_quirks(edid_buf, edid_caps);
+
kfree(sads);
kfree(sadb);
