@@ -334,12 +334,14 @@ EXPORT_SYMBOL(drm_dp_dpcd_read_link_status);
static void drm_dp_link_caps_reset(struct drm_dp_link_caps *caps)
{
caps->enhanced_framing = false;
+ caps->fast_training = false;
}
void drm_dp_link_caps_copy(struct drm_dp_link_caps *dest,
const struct drm_dp_link_caps *src)
{
dest->enhanced_framing = src->enhanced_framing;
+ dest->fast_training = src->fast_training;
}
EXPORT_SYMBOL(drm_dp_link_caps_copy);
@@ -385,6 +387,7 @@ int drm_dp_link_probe(struct drm_dp_aux *aux, struct drm_dp_link *link)
link->max_lanes = drm_dp_max_lane_count(values);
link->caps.enhanced_framing = drm_dp_enhanced_frame_cap(values);
+ link->caps.fast_training = drm_dp_fast_training_cap(values);
link->rate = link->max_rate;
link->lanes = link->max_lanes;
@@ -976,6 +976,13 @@ drm_dp_is_branch(const u8 dpcd[DP_RECEIVER_CAP_SIZE])
return dpcd[DP_DOWNSTREAMPORT_PRESENT] & DP_DWN_STRM_PORT_PRESENT;
}
+static inline bool
+drm_dp_fast_training_cap(const u8 dpcd[DP_RECEIVER_CAP_SIZE])
+{
+ return dpcd[DP_DPCD_REV] >= 0x11 &&
+ (dpcd[DP_MAX_DOWNSPREAD] & DP_NO_AUX_HANDSHAKE_LINK_TRAINING);
+}
+
/*
* DisplayPort AUX channel
*/
@@ -1103,9 +1110,11 @@ int drm_dp_dpcd_read_link_status(struct drm_dp_aux *aux,
/**
* struct drm_dp_link_caps - DP link capabilities
* @enhanced_framing: enhanced framing capability (mandatory as of DP 1.2)
+ * @fast_training: AUX CH handshake not required for link training
*/
struct drm_dp_link_caps {
bool enhanced_framing;
+ bool fast_training;
};
void drm_dp_link_caps_copy(struct drm_dp_link_caps *dest,