On Wed, Jul 06, 2016 at 02:04:48PM +0300, Mika Kahola wrote:
Helper routine to read out maximum supported bits per component for DisplayPort legay converters.
v2: Return early if detailed port cap info is not available. Replace if-else ladder with switch-case (Ville)
Reviewed-by: Jim Bride jim.bride@linux.intel.com
Signed-off-by: Mika Kahola mika.kahola@intel.com
drivers/gpu/drm/drm_dp_helper.c | 42 +++++++++++++++++++++++++++++++++++++++++ include/drm/drm_dp_helper.h | 2 ++ 2 files changed, 44 insertions(+)
diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c index 0d4117c..95d624a 100644 --- a/drivers/gpu/drm/drm_dp_helper.c +++ b/drivers/gpu/drm/drm_dp_helper.c @@ -471,6 +471,48 @@ int drm_dp_downstream_max_clock(const u8 dpcd[DP_RECEIVER_CAP_SIZE], } EXPORT_SYMBOL(drm_dp_downstream_max_clock);
+/**
- drm_dp_downstream_max_bpc() - extract branch device max
bits per component
- @dpcd: DisplayPort configuration data
- @port_cap: port capabilities
- Returns max bpc on success or 0 if max bpc not defined
- */
+int drm_dp_downstream_max_bpc(const u8 dpcd[DP_RECEIVER_CAP_SIZE],
const u8 port_cap[4])+{
- int type = port_cap[0] & DP_DS_PORT_TYPE_MASK;
- bool detailed_cap_info = dpcd[DP_DOWNSTREAMPORT_PRESENT] &
DP_DETAILED_CAP_INFO_AVAILABLE;- int bpc;
- if (!detailed_cap_info)
return 0;- switch (type) {
- case DP_DS_PORT_TYPE_VGA:
- case DP_DS_PORT_TYPE_DVI:
- case DP_DS_PORT_TYPE_HDMI:
- case DP_DS_PORT_TYPE_DP_DUALMODE:
bpc = port_cap[2] & DP_DS_MAX_BPC_MASK;switch (bpc) {case DP_DS_8BPC:return 8;case DP_DS_10BPC:return 10;case DP_DS_12BPC:return 12;case DP_DS_16BPC:return 16;}- default:
return 0;- }
+} +EXPORT_SYMBOL(drm_dp_downstream_max_bpc);
/*
- I2C-over-AUX implementation
*/ diff --git a/include/drm/drm_dp_helper.h b/include/drm/drm_dp_helper.h index de8e9ae..47ae8ed 100644 --- a/include/drm/drm_dp_helper.h +++ b/include/drm/drm_dp_helper.h @@ -808,6 +808,8 @@ int drm_dp_link_power_down(struct drm_dp_aux *aux, struct drm_dp_link *link); int drm_dp_link_configure(struct drm_dp_aux *aux, struct drm_dp_link *link); int drm_dp_downstream_max_clock(const u8 dpcd[DP_RECEIVER_CAP_SIZE], const u8 port_cap[4]); +int drm_dp_downstream_max_bpc(const u8 dpcd[DP_RECEIVER_CAP_SIZE],
const u8 port_cap[4]);void drm_dp_aux_init(struct drm_dp_aux *aux); int drm_dp_aux_register(struct drm_dp_aux *aux); -- 1.9.1