drm: Helper to read max clock rate
Helper routine to read out maximum supported pixel rate
for DisplayPort legay VGA converter or TMDS clock rate
for other digital legacy converters. The helper returns
clock rate in kHz.
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>
Acked-by: Dave Airlie <airlied@gmail.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1473419458-17080-4-git-send-email-mika.kahola@intel.com
diff --git a/include/drm/drm_dp_helper.h b/include/drm/drm_dp_helper.h
index 0d84046..60dd9dc 100644
--- a/include/drm/drm_dp_helper.h
+++ b/include/drm/drm_dp_helper.h
@@ -815,6 +815,8 @@
int drm_dp_link_power_up(struct drm_dp_aux *aux, struct drm_dp_link *link);
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]);
void drm_dp_aux_init(struct drm_dp_aux *aux);
int drm_dp_aux_register(struct drm_dp_aux *aux);