From: Sandor Yu <Sandor.yu@xxxxxxx> HDMI1.4b specification section 6.5.3: Source shall only send GCPs with non-zero CD to sinks that indicate support for Deep Color. DW HDMI GPC default enabled, clear gpc_auto bit for bpp 24. Signed-off-by: Sandor Yu <Sandor.yu@xxxxxxx> --- drivers/gpu/drm/bridge/synopsys/dw-hdmi.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c index b11577de4836..c7b11582529e 100644 --- a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c +++ b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c @@ -1160,6 +1160,14 @@ static void hdmi_video_packetize(struct dw_hdmi *hdmi) HDMI_VP_PR_CD_DESIRED_PR_FACTOR_MASK); hdmi_writeb(hdmi, val, HDMI_VP_PR_CD); + val = hdmi_readb(hdmi, HDMI_FC_DATAUTO3); + if (color_depth == 4) + /* disable Auto GCP when bpp 24 */ + val &= ~0x4; + else + val |= 0x4; + hdmi_writeb(hdmi, val, HDMI_FC_DATAUTO3); + hdmi_modb(hdmi, HDMI_VP_STUFF_PR_STUFFING_STUFFING_MODE, HDMI_VP_STUFF_PR_STUFFING_MASK, HDMI_VP_STUFF); -- 2.25.1
