When DP downstream has HDMI branch, it checks below functionality and shows supports. It follows DP 1.4a spec; Table 2-161: Address Mapping within DPCD Receiver Capability Field (DPCD Addresses 00000h through 000FFh).
Added flags for DP downstream: YCBCR422_PASS_THROUGH_SUPPORT, YCBCR420_PASS_THROUGH_SUPPORT, CONVERSION_FROM_YCBCR444_TO_YCBCR422_SUPPORT and CONVERSION_FROM_YCBCR444_TO_YCBCR420_SUPPORT.
Signed-off-by: Gwan-gyeong Mun gwan-gyeong.mun@intel.com --- drivers/gpu/drm/drm_dp_helper.c | 19 +++++++++++++++++++ include/drm/drm_dp_helper.h | 5 +++++ 2 files changed, 24 insertions(+)
diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c index 5a103e9b3c86..cb6dcfb13127 100644 --- a/drivers/gpu/drm/drm_dp_helper.c +++ b/drivers/gpu/drm/drm_dp_helper.c @@ -531,6 +531,25 @@ void drm_dp_downstream_debug(struct seq_file *m,
if (bpc > 0) seq_printf(m, "\t\tMax bpc: %d\n", bpc); + + if (type == DP_DS_PORT_TYPE_HDMI) { + bool ycbcr422_passthru = port_cap[3] & + DP_DS_YCBCR422_PASSTHRU_SUPPORT; + bool ycbcr420_passthru = port_cap[3] & + DP_DS_YCBCR420_PASSTHRU_SUPPORT; + bool ycbcr422_convert = port_cap[3] & + DP_DS_CONV_YCBCR444_TO_YCBCR422_SUPPORT; + bool ycbcr420_convert = port_cap[3] & + DP_DS_CONV_YCBCR444_TO_YCBCR420_SUPPORT; + seq_printf(m, "\t\tHDMI YCbCr 4:2:2 pass-through support: %s\n", + ycbcr422_passthru ? "yes" : "no"); + seq_printf(m, "\t\tHDMI YCbCr 4:2:0 pass-through support: %s\n", + ycbcr420_passthru ? "yes" : "no"); + seq_printf(m, "\t\tHDMI YCbCr 4:4:4 to YCbCr 4:2:2 Convert support: %s\n", + ycbcr422_convert ? "yes" : "no"); + seq_printf(m, "\t\tHDMI YCbCr 4:4:4 to YCbCr 4:2:0 Convert support: %s\n", + ycbcr420_convert ? "yes" : "no"); + } } } EXPORT_SYMBOL(drm_dp_downstream_debug); diff --git a/include/drm/drm_dp_helper.h b/include/drm/drm_dp_helper.h index 262faf9e5e94..d61eadaba769 100644 --- a/include/drm/drm_dp_helper.h +++ b/include/drm/drm_dp_helper.h @@ -391,6 +391,11 @@ # define DP_DS_10BPC 1 # define DP_DS_12BPC 2 # define DP_DS_16BPC 3 +/* offset 3 for HDMI */ +# define DP_DS_YCBCR422_PASSTHRU_SUPPORT (1 << 1) /* 1.4 */ +# define DP_DS_YCBCR420_PASSTHRU_SUPPORT (1 << 2) +# define DP_DS_CONV_YCBCR444_TO_YCBCR422_SUPPORT (1 << 3) +# define DP_DS_CONV_YCBCR444_TO_YCBCR420_SUPPORT (1 << 4)
#define DP_MAX_DOWNSTREAM_PORTS 0x10