Merge "disp: msm: dp: add 1.4a cts support for link training" (90ae2587) · Commits · e / devices / android_kernel_fairphone_FP4

msm/dp/dp_ctrl.c

+37 −5

Original line number	Diff line number	Diff line
		@@ -74,6 +74,7 @@ struct dp_ctrl_private {
		atomic_t aborted;

		u8 initial_lane_count;
		u8 initial_bw_code;

		u32 vic;
		u32 stream_count;
		@@ -295,6 +296,26 @@ static int dp_ctrl_lane_count_down_shift(struct dp_ctrl_private *ctrl)
		return ret;
		}

		static bool dp_ctrl_is_link_rate_rbr(struct dp_ctrl_private *ctrl)
		{
		return ctrl->link->link_params.bw_code == DP_LINK_BW_1_62;
		}

		static u8 dp_ctrl_get_active_lanes(struct dp_ctrl_private *ctrl,
		u8 *link_status)
		{
		u8 lane, count = 0;

		for (lane = 0; lane < ctrl->link->link_params.lane_count; lane++) {
		if (link_status[lane / 2] & (1 << (lane * 4)))
		count++;
		else
		break;
		}

		return count;
		}

		static int dp_ctrl_link_training_1(struct dp_ctrl_private *ctrl)
		{
		int tries, old_v_level, ret = -EINVAL;
		@@ -343,15 +364,13 @@ static int dp_ctrl_link_training_1(struct dp_ctrl_private *ctrl)
		else
		break;


		if (ctrl->link->phy_params.v_level == DP_LINK_VOLTAGE_MAX) {
		pr_err_ratelimited("max v_level reached\n");
		break;
		}

		if (old_v_level == ctrl->link->phy_params.v_level) {
		tries++;
		if (tries >= maximum_retries) {
		if (++tries >= maximum_retries) {
		pr_err("max tries reached\n");
		ret = -ETIMEDOUT;
		break;
		@@ -366,6 +385,18 @@ static int dp_ctrl_link_training_1(struct dp_ctrl_private *ctrl)
		ctrl->link->adjust_levels(ctrl->link, link_status);
		}

		if (ret && dp_ctrl_is_link_rate_rbr(ctrl)) {
		u8 active_lanes = dp_ctrl_get_active_lanes(ctrl, link_status);

		if (active_lanes) {
		ctrl->link->link_params.lane_count = active_lanes;
		ctrl->link->link_params.bw_code = ctrl->initial_bw_code;

		/* retry with new settings */
		ret = -EAGAIN;
		}
		}

		ctrl->aux->state &= ~DP_STATE_TRAIN_1_STARTED;

		if (ret)
		@@ -467,7 +498,7 @@ static int dp_ctrl_link_training_2(struct dp_ctrl_private *ctrl)
		else
		break;

		if (tries > maximum_retries) {
		if (tries >= maximum_retries) {
		ret = dp_ctrl_lane_count_down_shift(ctrl);
		break;
		}
		@@ -1227,8 +1258,9 @@ static int dp_ctrl_on(struct dp_ctrl *dp_ctrl, bool mst_mode,
		ctrl->link->link_params.bw_code,
		ctrl->link->link_params.lane_count);

		/* backup initial lane count */
		/* backup initial lane count and bw code */
		ctrl->initial_lane_count = ctrl->link->link_params.lane_count;
		ctrl->initial_bw_code = ctrl->link->link_params.bw_code;

		rc = dp_ctrl_link_setup(ctrl, shallow);
		ctrl->power_on = true;