From: Tobias Jakobi <tjakobi@xxxxxxxxxxxxxxxxxxxxx> This 8.4 inch panel is integrated in the Ayaneo Kun handheld device. The panel resolution is 2560×1600, i.e. it has portrait dimensions. Decoding the EDID shows: Manufacturer: MSF Model: 4099 Display Product Name: 'TV080WUM-NL0 ' Judging from the product name this might be a clone of a BOE panel, but with larger dimensions. Panel frequently shows non-functional backlight control. Adding some debug prints to update_connector_ext_caps() shows that something the OLED bit of ext_caps is set, and then the driver assumes that backlight is controlled via AUX. Forcing backlight control to PWM via amdgpu.backlight=0 restores backlight operation. Signed-off-by: Tobias Jakobi <tjakobi@xxxxxxxxxxxxxxxxxxxxx> --- drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c index 7a09a72e182f..5a017ba94e3c 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c @@ -68,6 +68,7 @@ static void apply_edid_quirks(struct edid *edid, struct dc_edid_caps *edid_caps) case drm_edid_encode_panel_id('A', 'U', 'O', 0xE69B): case drm_edid_encode_panel_id('B', 'O', 'E', 0x092A): case drm_edid_encode_panel_id('L', 'G', 'D', 0x06D1): + case drm_edid_encode_panel_id('M', 'S', 'F', 0x1003): DRM_DEBUG_DRIVER("Clearing DPCD 0x317 on monitor with panel id %X\n", panel_id); edid_caps->panel_patch.remove_sink_ext_caps = true; break; -- 2.43.0