7 files changed, 177 insertions, 119 deletions

diff --git a/drivers/gpu/drm/msm/dp/dp_aux.c b/drivers/gpu/drm/msm/dp/dp_aux.c
index 4a3293b590b0..eb40d8413bca 100644
--- a/drivers/gpu/drm/msm/dp/dp_aux.c
+++ b/drivers/gpu/drm/msm/dp/dp_aux.c
@@ -353,6 +353,9 @@ static ssize_t dp_aux_transfer(struct drm_dp_aux *dp_aux,
 			if (!(aux->retry_cnt % MAX_AUX_RETRIES))
 				dp_catalog_aux_update_cfg(aux->catalog);
 		}
+		/* reset aux if link is in connected state */
+		if (dp_catalog_link_is_connected(aux->catalog))
+			dp_catalog_aux_reset(aux->catalog);
 	} else {
 		aux->retry_cnt = 0;
 		switch (aux->aux_error_num) {
diff --git a/drivers/gpu/drm/msm/dp/dp_catalog.c b/drivers/gpu/drm/msm/dp/dp_catalog.c
index ca96e3514790..cc2bb8295329 100644
--- a/drivers/gpu/drm/msm/dp/dp_catalog.c
+++ b/drivers/gpu/drm/msm/dp/dp_catalog.c
@@ -372,6 +372,7 @@ void dp_catalog_ctrl_mainlink_ctrl(struct dp_catalog *dp_catalog,
 	struct dp_catalog_private *catalog = container_of(dp_catalog,
 				struct dp_catalog_private, dp_catalog);
 
+	DRM_DEBUG_DP("enable=%d\n", enable);
 	if (enable) {
 		/*
 		 * To make sure link reg writes happens before other operation,
@@ -580,6 +581,7 @@ void dp_catalog_hpd_config_intr(struct dp_catalog *dp_catalog,
 
 	config = (en ? config | intr_mask : config & ~intr_mask);
 
+	DRM_DEBUG_DP("intr_mask=%#x config=%#x\n", intr_mask, config);
 	dp_write_aux(catalog, REG_DP_DP_HPD_INT_MASK,
 				config & DP_DP_HPD_INT_MASK);
 }
@@ -610,6 +612,7 @@ u32 dp_catalog_link_is_connected(struct dp_catalog *dp_catalog)
 	u32 status;
 
 	status = dp_read_aux(catalog, REG_DP_DP_HPD_INT_STATUS);
+	DRM_DEBUG_DP("aux status: %#x\n", status);
 	status >>= DP_DP_HPD_STATE_STATUS_BITS_SHIFT;
 	status &= DP_DP_HPD_STATE_STATUS_BITS_MASK;
 
@@ -685,6 +688,7 @@ void dp_catalog_ctrl_send_phy_pattern(struct dp_catalog *dp_catalog,
 	/* Make sure to clear the current pattern before starting a new one */
 	dp_write_link(catalog, REG_DP_STATE_CTRL, 0x0);
 
+	DRM_DEBUG_DP("pattern: %#x\n", pattern);
 	switch (pattern) {
 	case DP_PHY_TEST_PATTERN_D10_2:
 		dp_write_link(catalog, REG_DP_STATE_CTRL,
@@ -745,7 +749,7 @@ void dp_catalog_ctrl_send_phy_pattern(struct dp_catalog *dp_catalog,
 				DP_STATE_CTRL_LINK_TRAINING_PATTERN4);
 		break;
 	default:
-		DRM_DEBUG_DP("No valid test pattern requested:0x%x\n", pattern);
+		DRM_DEBUG_DP("No valid test pattern requested: %#x\n", pattern);
 		break;
 	}
 }
@@ -771,6 +775,7 @@ int dp_catalog_panel_timing_cfg(struct dp_catalog *dp_catalog)
 	dp_write_link(catalog, REG_DP_HSYNC_VSYNC_WIDTH_POLARITY,
 				dp_catalog->width_blanking);
 	dp_write_link(catalog, REG_DP_ACTIVE_HOR_VER, dp_catalog->dp_active);
+	dp_write_p0(catalog, MMSS_DP_INTF_CONFIG, 0);
 	return 0;
 }
 
@@ -928,7 +933,7 @@ void dp_catalog_audio_config_acr(struct dp_catalog *dp_catalog)
 	select = dp_catalog->audio_data;
 	acr_ctrl = select << 4 | BIT(31) | BIT(8) | BIT(14);
 
-	DRM_DEBUG_DP("select = 0x%x, acr_ctrl = 0x%x\n", select, acr_ctrl);
+	DRM_DEBUG_DP("select: %#x, acr_ctrl: %#x\n", select, acr_ctrl);
 
 	dp_write_link(catalog, MMSS_DP_AUDIO_ACR_CTRL, acr_ctrl);
 }
diff --git a/drivers/gpu/drm/msm/dp/dp_ctrl.c b/drivers/gpu/drm/msm/dp/dp_ctrl.c
index ee221d835fa0..62e75dc8afc6 100644
--- a/drivers/gpu/drm/msm/dp/dp_ctrl.c
+++ b/drivers/gpu/drm/msm/dp/dp_ctrl.c
@@ -81,13 +81,6 @@ struct dp_ctrl_private {
 	struct completion video_comp;
 };
 
-struct dp_cr_status {
-	u8 lane_0_1;
-	u8 lane_2_3;
-};
-
-#define DP_LANE0_1_CR_DONE	0x11
-
 static int dp_aux_link_configure(struct drm_dp_aux *aux,
 					struct dp_link_info *link)
 {
@@ -120,7 +113,7 @@ void dp_ctrl_push_idle(struct dp_ctrl *dp_ctrl)
 			IDLE_PATTERN_COMPLETION_TIMEOUT_JIFFIES))
 		pr_warn("PUSH_IDLE pattern timedout\n");
 
-	pr_debug("mainlink off done\n");
+	DRM_DEBUG_DP("mainlink off done\n");
 }
 
 static void dp_ctrl_config_ctrl(struct dp_ctrl_private *ctrl)
@@ -1011,6 +1004,8 @@ static int dp_ctrl_update_vx_px(struct dp_ctrl_private *ctrl)
 	u32 voltage_swing_level = link->phy_params.v_level;
 	u32 pre_emphasis_level = link->phy_params.p_level;
 
+	DRM_DEBUG_DP("voltage level: %d emphasis level: %d\n", voltage_swing_level,
+			pre_emphasis_level);
 	ret = dp_catalog_ctrl_update_vx_px(ctrl->catalog,
 		voltage_swing_level, pre_emphasis_level);
 
@@ -1078,7 +1073,7 @@ static int dp_ctrl_read_link_status(struct dp_ctrl_private *ctrl,
 }
 
 static int dp_ctrl_link_train_1(struct dp_ctrl_private *ctrl,
-		struct dp_cr_status *cr, int *training_step)
+			int *training_step)
 {
 	int tries, old_v_level, ret = 0;
 	u8 link_status[DP_LINK_STATUS_SIZE];
@@ -1107,9 +1102,6 @@ static int dp_ctrl_link_train_1(struct dp_ctrl_private *ctrl,
 		if (ret)
 			return ret;
 
-		cr->lane_0_1 = link_status[0];
-		cr->lane_2_3 = link_status[1];
-
 		if (drm_dp_clock_recovery_ok(link_status,
 			ctrl->link->link_params.num_lanes)) {
 			return 0;
@@ -1186,7 +1178,7 @@ static void dp_ctrl_clear_training_pattern(struct dp_ctrl_private *ctrl)
 }
 
 static int dp_ctrl_link_train_2(struct dp_ctrl_private *ctrl,
-		struct dp_cr_status *cr, int *training_step)
+			int *training_step)
 {
 	int tries = 0, ret = 0;
 	char pattern;
@@ -1202,10 +1194,6 @@ static int dp_ctrl_link_train_2(struct dp_ctrl_private *ctrl,
 	else
 		pattern = DP_TRAINING_PATTERN_2;
 
-	ret = dp_ctrl_update_vx_px(ctrl);
-	if (ret)
-		return ret;
-
 	ret = dp_catalog_ctrl_set_pattern(ctrl->catalog, pattern);
 	if (ret)
 		return ret;
@@ -1218,8 +1206,6 @@ static int dp_ctrl_link_train_2(struct dp_ctrl_private *ctrl,
 		ret = dp_ctrl_read_link_status(ctrl, link_status);
 		if (ret)
 			return ret;
-		cr->lane_0_1 = link_status[0];
-		cr->lane_2_3 = link_status[1];
 
 		if (drm_dp_channel_eq_ok(link_status,
 			ctrl->link->link_params.num_lanes)) {
@@ -1239,7 +1225,7 @@ static int dp_ctrl_link_train_2(struct dp_ctrl_private *ctrl,
 static int dp_ctrl_reinitialize_mainlink(struct dp_ctrl_private *ctrl);
 
 static int dp_ctrl_link_train(struct dp_ctrl_private *ctrl,
-		struct dp_cr_status *cr, int *training_step)
+			int *training_step)
 {
 	int ret = 0;
 	u8 encoding = DP_SET_ANSI_8B10B;
@@ -1255,7 +1241,7 @@ static int dp_ctrl_link_train(struct dp_ctrl_private *ctrl,
 	drm_dp_dpcd_write(ctrl->aux, DP_MAIN_LINK_CHANNEL_CODING_SET,
 				&encoding, 1);
 
-	ret = dp_ctrl_link_train_1(ctrl, cr, training_step);
+	ret = dp_ctrl_link_train_1(ctrl, training_step);
 	if (ret) {
 		DRM_ERROR("link training #1 failed. ret=%d\n", ret);
 		goto end;
@@ -1264,7 +1250,7 @@ static int dp_ctrl_link_train(struct dp_ctrl_private *ctrl,
 	/* print success info as this is a result of user initiated action */
 	DRM_DEBUG_DP("link training #1 successful\n");
 
-	ret = dp_ctrl_link_train_2(ctrl, cr, training_step);
+	ret = dp_ctrl_link_train_2(ctrl, training_step);
 	if (ret) {
 		DRM_ERROR("link training #2 failed. ret=%d\n", ret);
 		goto end;
@@ -1280,7 +1266,7 @@ end:
 }
 
 static int dp_ctrl_setup_main_link(struct dp_ctrl_private *ctrl,
-		struct dp_cr_status *cr, int *training_step)
+			int *training_step)
 {
 	int ret = 0;
 
@@ -1295,7 +1281,7 @@ static int dp_ctrl_setup_main_link(struct dp_ctrl_private *ctrl,
 	 * a link training pattern, we have to first do soft reset.
 	 */
 
-	ret = dp_ctrl_link_train(ctrl, cr, training_step);
+	ret = dp_ctrl_link_train(ctrl, training_step);
 
 	return ret;
 }
@@ -1382,6 +1368,7 @@ int dp_ctrl_host_init(struct dp_ctrl *dp_ctrl, bool flip, bool reset)
 	if (reset)
 		dp_catalog_ctrl_reset(ctrl->catalog);
 
+	DRM_DEBUG_DP("flip=%d\n", flip);
 	dp_catalog_ctrl_phy_reset(ctrl->catalog);
 	phy_init(phy);
 	dp_catalog_ctrl_enable_irq(ctrl->catalog, true);
@@ -1492,14 +1479,16 @@ static int dp_ctrl_deinitialize_mainlink(struct dp_ctrl_private *ctrl)
 static int dp_ctrl_link_maintenance(struct dp_ctrl_private *ctrl)
 {
 	int ret = 0;
-	struct dp_cr_status cr;
 	int training_step = DP_TRAINING_NONE;
 
 	dp_ctrl_push_idle(&ctrl->dp_ctrl);
 
+	ctrl->link->phy_params.p_level = 0;
+	ctrl->link->phy_params.v_level = 0;
+
 	ctrl->dp_ctrl.pixel_rate = ctrl->panel->dp_mode.drm_mode.clock;
 
-	ret = dp_ctrl_setup_main_link(ctrl, &cr, &training_step);
+	ret = dp_ctrl_setup_main_link(ctrl, &training_step);
 	if (ret)
 		goto end;
 
@@ -1526,7 +1515,7 @@ static int dp_ctrl_process_phy_test_request(struct dp_ctrl_private *ctrl)
 	 * running. Add the global reset just before disabling the
 	 * link clocks and core clocks.
 	 */
-	ret = dp_ctrl_off(&ctrl->dp_ctrl);
+	ret = dp_ctrl_off_link_stream(&ctrl->dp_ctrl);
 	if (ret) {
 		DRM_ERROR("failed to disable DP controller\n");
 		return ret;
@@ -1630,6 +1619,35 @@ void dp_ctrl_handle_sink_request(struct dp_ctrl *dp_ctrl)
 	}
 }
 
+static bool dp_ctrl_clock_recovery_any_ok(
+			const u8 link_status[DP_LINK_STATUS_SIZE],
+			int lane_count)
+{
+	int reduced_cnt;
+
+	if (lane_count <= 1)
+		return false;
+
+	/*
+	 * only interested in the lane number after reduced
+	 * lane_count = 4, then only interested in 2 lanes
+	 * lane_count = 2, then only interested in 1 lane
+	 */
+	reduced_cnt = lane_count >> 1;
+
+	return drm_dp_clock_recovery_ok(link_status, reduced_cnt);
+}
+
+static bool dp_ctrl_channel_eq_ok(struct dp_ctrl_private *ctrl)
+{
+	u8 link_status[DP_LINK_STATUS_SIZE];
+	int num_lanes = ctrl->link->link_params.num_lanes;
+
+	dp_ctrl_read_link_status(ctrl, link_status);
+
+	return drm_dp_channel_eq_ok(link_status, num_lanes);
+}
+
 int dp_ctrl_on_link(struct dp_ctrl *dp_ctrl)
 {
 	int rc = 0;
@@ -1637,7 +1655,7 @@ int dp_ctrl_on_link(struct dp_ctrl *dp_ctrl)
 	u32 rate = 0;
 	int link_train_max_retries = 5;
 	u32 const phy_cts_pixel_clk_khz = 148500;
-	struct dp_cr_status cr;
+	u8 link_status[DP_LINK_STATUS_SIZE];
 	unsigned int training_step;
 
 	if (!dp_ctrl)
@@ -1664,6 +1682,9 @@ int dp_ctrl_on_link(struct dp_ctrl *dp_ctrl)
 		ctrl->link->link_params.rate,
 		ctrl->link->link_params.num_lanes, ctrl->dp_ctrl.pixel_rate);
 
+	ctrl->link->phy_params.p_level = 0;
+	ctrl->link->phy_params.v_level = 0;
+
 	rc = dp_ctrl_enable_mainlink_clocks(ctrl);
 	if (rc)
 		return rc;
@@ -1677,19 +1698,21 @@ int dp_ctrl_on_link(struct dp_ctrl *dp_ctrl)
 		}
 
 		training_step = DP_TRAINING_NONE;
-		rc = dp_ctrl_setup_main_link(ctrl, &cr, &training_step);
+		rc = dp_ctrl_setup_main_link(ctrl, &training_step);
 		if (rc == 0) {
 			/* training completed successfully */
 			break;
 		} else if (training_step == DP_TRAINING_1) {
 			/* link train_1 failed */
-			if (!dp_catalog_link_is_connected(ctrl->catalog)) {
+			if (!dp_catalog_link_is_connected(ctrl->catalog))
 				break;
-			}
+
+			dp_ctrl_read_link_status(ctrl, link_status);
 
 			rc = dp_ctrl_link_rate_down_shift(ctrl);
 			if (rc < 0) { /* already in RBR = 1.6G */
-				if (cr.lane_0_1 & DP_LANE0_1_CR_DONE) {
+				if (dp_ctrl_clock_recovery_any_ok(link_status,
+					ctrl->link->link_params.num_lanes)) {
 					/*
 					 * some lanes are ready,
 					 * reduce lane number
@@ -1705,12 +1728,18 @@ int dp_ctrl_on_link(struct dp_ctrl *dp_ctrl)
 				}
 			}
 		} else if (training_step == DP_TRAINING_2) {
-			/* link train_2 failed, lower lane rate */
-			if (!dp_catalog_link_is_connected(ctrl->catalog)) {
+			/* link train_2 failed */
+			if (!dp_catalog_link_is_connected(ctrl->catalog))
 				break;
-			}
 
-			rc = dp_ctrl_link_lane_down_shift(ctrl);
+			dp_ctrl_read_link_status(ctrl, link_status);
+
+			if (!drm_dp_clock_recovery_ok(link_status,
+					ctrl->link->link_params.num_lanes))
+				rc = dp_ctrl_link_rate_down_shift(ctrl);
+			else
+				rc = dp_ctrl_link_lane_down_shift(ctrl);
+
 			if (rc < 0) {
 				/* end with failure */
 				break; /* lane == 1 already */
@@ -1721,17 +1750,19 @@ int dp_ctrl_on_link(struct dp_ctrl *dp_ctrl)
 	if (ctrl->link->sink_request & DP_TEST_LINK_PHY_TEST_PATTERN)
 		return rc;
 
-	/* stop txing train pattern */
-	dp_ctrl_clear_training_pattern(ctrl);
+	if (rc == 0) {  /* link train successfully */
+		/*
+		 * do not stop train pattern here
+		 * stop link training at on_stream
+		 * to pass compliance test
+		 */
+	} else  {
+		/*
+		 * link training failed
+		 * end txing train pattern here
+		 */
+		dp_ctrl_clear_training_pattern(ctrl);
 
-	/*
-	 * keep transmitting idle pattern until video ready
-	 * to avoid main link from loss of sync
-	 */
-	if (rc == 0)  /* link train successfully */
-		dp_ctrl_push_idle(dp_ctrl);
-	else  {
-		/* link training failed */
 		dp_ctrl_deinitialize_mainlink(ctrl);
 		rc = -ECONNRESET;
 	}
@@ -1739,9 +1770,15 @@ int dp_ctrl_on_link(struct dp_ctrl *dp_ctrl)
 	return rc;
 }
 
+static int dp_ctrl_link_retrain(struct dp_ctrl_private *ctrl)
+{
+	int training_step = DP_TRAINING_NONE;
+
+	return dp_ctrl_setup_main_link(ctrl, &training_step);
+}
+
 int dp_ctrl_on_stream(struct dp_ctrl *dp_ctrl)
 {
-	u32 rate = 0;
 	int ret = 0;
 	bool mainlink_ready = false;
 	struct dp_ctrl_private *ctrl;
@@ -1751,10 +1788,6 @@ int dp_ctrl_on_stream(struct dp_ctrl *dp_ctrl)
 
 	ctrl = container_of(dp_ctrl, struct dp_ctrl_private, dp_ctrl);
 
-	rate = ctrl->panel->link_info.rate;
-
-	ctrl->link->link_params.rate = rate;
-	ctrl->link->link_params.num_lanes = ctrl->panel->link_info.num_lanes;
 	ctrl->dp_ctrl.pixel_rate = ctrl->panel->dp_mode.drm_mode.clock;
 
 	DRM_DEBUG_DP("rate=%d, num_lanes=%d, pixel_rate=%d\n",
@@ -1769,6 +1802,12 @@ int dp_ctrl_on_stream(struct dp_ctrl *dp_ctrl)
 		}
 	}
 
+	if (!dp_ctrl_channel_eq_ok(ctrl))
+		dp_ctrl_link_retrain(ctrl);
+
+	/* stop txing train pattern to end link training */
+	dp_ctrl_clear_training_pattern(ctrl);
+
 	ret = dp_ctrl_enable_stream_clocks(ctrl);
 	if (ret) {
 		DRM_ERROR("Failed to start pixel clocks. ret=%d\n", ret);
diff --git a/drivers/gpu/drm/msm/dp/dp_display.c b/drivers/gpu/drm/msm/dp/dp_display.c
index 051c1be1de7e..fbe4c2cd52a3 100644
--- a/drivers/gpu/drm/msm/dp/dp_display.c
+++ b/drivers/gpu/drm/msm/dp/dp_display.c
@@ -55,7 +55,6 @@ enum {
 	EV_HPD_INIT_SETUP,
 	EV_HPD_PLUG_INT,
 	EV_IRQ_HPD_INT,
-	EV_HPD_REPLUG_INT,
 	EV_HPD_UNPLUG_INT,
 	EV_USER_NOTIFICATION,
 	EV_CONNECT_PENDING_TIMEOUT,
@@ -102,8 +101,6 @@ struct dp_display_private {
 	struct dp_display_mode dp_mode;
 	struct msm_dp dp_display;
 
-	bool encoder_mode_set;
-
 	/* wait for audio signaling */
 	struct completion audio_comp;
 
@@ -219,6 +216,7 @@ static int dp_display_bind(struct device *dev, struct device *master,
 		goto end;
 	}
 
+	dp->aux->drm_dev = drm;
 	rc = dp_aux_register(dp->aux);
 	if (rc) {
 		DRM_ERROR("DRM DP AUX register failed\n");
@@ -267,6 +265,8 @@ static bool dp_display_is_ds_bridge(struct dp_panel *panel)
 
 static bool dp_display_is_sink_count_zero(struct dp_display_private *dp)
 {
+	DRM_DEBUG_DP("present=%#x sink_count=%d\n", dp->panel->dpcd[DP_DOWNSTREAMPORT_PRESENT],
+		dp->link->sink_count);
 	return dp_display_is_ds_bridge(dp->panel) &&
 		(dp->link->sink_count == 0);
 }
@@ -283,20 +283,6 @@ static void dp_display_send_hpd_event(struct msm_dp *dp_display)
 }
 
 
-static void dp_display_set_encoder_mode(struct dp_display_private *dp)
-{
-	struct msm_drm_private *priv = dp->dp_display.drm_dev->dev_private;
-	struct msm_kms *kms = priv->kms;
-
-	if (!dp->encoder_mode_set && dp->dp_display.encoder &&
-				kms->funcs->set_encoder_mode) {
-		kms->funcs->set_encoder_mode(kms,
-				dp->dp_display.encoder, false);
-
-		dp->encoder_mode_set = true;
-	}
-}
-
 static int dp_display_send_hpd_notification(struct dp_display_private *dp,
 					    bool hpd)
 {
@@ -312,6 +298,7 @@ static int dp_display_send_hpd_notification(struct dp_display_private *dp,
 
 	dp->dp_display.is_connected = hpd;
 
+	DRM_DEBUG_DP("hpd=%d\n", hpd);
 	dp_display_send_hpd_event(&dp->dp_display);
 
 	return 0;
@@ -361,6 +348,7 @@ static void dp_display_host_init(struct dp_display_private *dp, int reset)
 {
 	bool flip = false;
 
+	DRM_DEBUG_DP("core_initialized=%d\n", dp->core_initialized);
 	if (dp->core_initialized) {
 		DRM_DEBUG_DP("DP core already initialized\n");
 		return;
@@ -369,8 +357,6 @@ static void dp_display_host_init(struct dp_display_private *dp, int reset)
 	if (dp->usbpd->orientation == ORIENTATION_CC2)
 		flip = true;
 
-	dp_display_set_encoder_mode(dp);
-
 	dp_power_init(dp->power, flip);
 	dp_ctrl_host_init(dp->ctrl, flip, reset);
 	dp_aux_init(dp->aux);
@@ -465,8 +451,10 @@ static int dp_display_handle_irq_hpd(struct dp_display_private *dp)
 {
 	u32 sink_request = dp->link->sink_request;
 
+	DRM_DEBUG_DP("%d\n", sink_request);
 	if (dp->hpd_state == ST_DISCONNECTED) {
 		if (sink_request & DP_LINK_STATUS_UPDATED) {
+			DRM_DEBUG_DP("Disconnected sink_request: %d\n", sink_request);
 			DRM_ERROR("Disconnected, no DP_LINK_STATUS_UPDATED\n");
 			return -EINVAL;
 		}
@@ -498,6 +486,7 @@ static int dp_display_usbpd_attention_cb(struct device *dev)
 	rc = dp_link_process_request(dp->link);
 	if (!rc) {
 		sink_request = dp->link->sink_request;
+		DRM_DEBUG_DP("hpd_state=%d sink_request=%d\n", dp->hpd_state, sink_request);
 		if (sink_request & DS_PORT_STATUS_CHANGED)
 			rc = dp_display_handle_port_ststus_changed(dp);
 		else
@@ -520,6 +509,7 @@ static int dp_hpd_plug_handle(struct dp_display_private *dp, u32 data)
 	mutex_lock(&dp->event_mutex);
 
 	state =  dp->hpd_state;
+	DRM_DEBUG_DP("hpd_state=%d\n", state);
 	if (state == ST_DISPLAY_OFF || state == ST_SUSPENDED) {
 		mutex_unlock(&dp->event_mutex);
 		return 0;
@@ -655,6 +645,7 @@ static int dp_hpd_unplug_handle(struct dp_display_private *dp, u32 data)
 	/* start sentinel checking in case of missing uevent */
 	dp_add_event(dp, EV_DISCONNECT_PENDING_TIMEOUT, 0, DP_TIMEOUT_5_SECOND);
 
+	DRM_DEBUG_DP("hpd_state=%d\n", state);
 	/* signal the disconnect event early to ensure proper teardown */
 	dp_display_handle_plugged_change(g_dp_display, false);
 
@@ -713,6 +704,7 @@ static int dp_irq_hpd_handle(struct dp_display_private *dp, u32 data)
 	if (ret == -ECONNRESET) { /* cable unplugged */
 		dp->core_initialized = false;
 	}
+	DRM_DEBUG_DP("hpd_state=%d\n", state);
 
 	mutex_unlock(&dp->event_mutex);
 
@@ -854,6 +846,7 @@ static int dp_display_enable(struct dp_display_private *dp, u32 data)
 
 	dp_display = g_dp_display;
 
+	DRM_DEBUG_DP("sink_count=%d\n", dp->link->sink_count);
 	if (dp_display->power_on) {
 		DRM_DEBUG_DP("Link already setup, return\n");
 		return 0;
@@ -915,6 +908,7 @@ static int dp_display_disable(struct dp_display_private *dp, u32 data)
 
 	dp_display->power_on = false;
 
+	DRM_DEBUG_DP("sink count: %d\n", dp->link->sink_count);
 	return 0;
 }
 
@@ -1014,10 +1008,8 @@ int dp_display_get_test_bpp(struct msm_dp *dp)
 void msm_dp_snapshot(struct msm_disp_state *disp_state, struct msm_dp *dp)
 {
 	struct dp_display_private *dp_display;
-	struct drm_device *drm;
 
 	dp_display = container_of(dp, struct dp_display_private, dp_display);
-	drm = dp->drm_dev;
 
 	/*
 	 * if we are reading registers we need the link clocks to be on
@@ -1118,9 +1110,6 @@ static int hpd_event_thread(void *data)
 		case EV_IRQ_HPD_INT:
 			dp_irq_hpd_handle(dp_priv, todo->data);
 			break;
-		case EV_HPD_REPLUG_INT:
-			/* do nothing */
-			break;
 		case EV_USER_NOTIFICATION:
 			dp_display_send_hpd_notification(dp_priv,
 						todo->data);
@@ -1162,12 +1151,11 @@ static irqreturn_t dp_display_irq_handler(int irq, void *dev_id)
 
 	hpd_isr_status = dp_catalog_hpd_get_intr_status(dp->catalog);
 
+	DRM_DEBUG_DP("hpd isr status=%#x\n", hpd_isr_status);
 	if (hpd_isr_status & 0x0F) {
 		/* hpd related interrupts */
-		if (hpd_isr_status & DP_DP_HPD_PLUG_INT_MASK ||
-			hpd_isr_status & DP_DP_HPD_REPLUG_INT_MASK) {
+		if (hpd_isr_status & DP_DP_HPD_PLUG_INT_MASK)
 			dp_add_event(dp, EV_HPD_PLUG_INT, 0, 0);
-		}
 
 		if (hpd_isr_status & DP_DP_IRQ_HPD_INT_MASK) {
 			/* stop sentinel connect pending checking */
@@ -1175,8 +1163,10 @@ static irqreturn_t dp_display_irq_handler(int irq, void *dev_id)
 			dp_add_event(dp, EV_IRQ_HPD_INT, 0, 0);
 		}
 
-		if (hpd_isr_status & DP_DP_HPD_REPLUG_INT_MASK)
-			dp_add_event(dp, EV_HPD_REPLUG_INT, 0, 0);
+		if (hpd_isr_status & DP_DP_HPD_REPLUG_INT_MASK) {
+			dp_add_event(dp, EV_HPD_UNPLUG_INT, 0, 0);
+			dp_add_event(dp, EV_HPD_PLUG_INT, 0, 3);
+		}
 
 		if (hpd_isr_status & DP_DP_HPD_UNPLUG_INT_MASK)
 			dp_add_event(dp, EV_HPD_UNPLUG_INT, 0, 0);
@@ -1285,12 +1275,15 @@ static int dp_pm_resume(struct device *dev)
 	struct platform_device *pdev = to_platform_device(dev);
 	struct msm_dp *dp_display = platform_get_drvdata(pdev);
 	struct dp_display_private *dp;
-	u32 status;
+	int sink_count = 0;
 
 	dp = container_of(dp_display, struct dp_display_private, dp_display);
 
 	mutex_lock(&dp->event_mutex);
 
+	DRM_DEBUG_DP("Before, core_inited=%d power_on=%d\n",
+			dp->core_initialized, dp_display->power_on);
+
 	/* start from disconnected state */
 	dp->hpd_state = ST_DISCONNECTED;
 
@@ -1299,18 +1292,36 @@ static int dp_pm_resume(struct device *dev)
 
 	dp_catalog_ctrl_hpd_config(dp->catalog);
 
-	status = dp_catalog_link_is_connected(dp->catalog);
+	/*
+	 * set sink to normal operation mode -- D0
+	 * before dpcd read
+	 */
+	dp_link_psm_config(dp->link, &dp->panel->link_info, false);
+
+	if (dp_catalog_link_is_connected(dp->catalog)) {
+		sink_count = drm_dp_read_sink_count(dp->aux);
+		if (sink_count < 0)
+			sink_count = 0;
+	}
 
+	dp->link->sink_count = sink_count;
 	/*
 	 * can not declared display is connected unless
 	 * HDMI cable is plugged in and sink_count of
 	 * dongle become 1
 	 */
-	if (status && dp->link->sink_count)
+	if (dp->link->sink_count)
 		dp->dp_display.is_connected = true;
 	else
 		dp->dp_display.is_connected = false;
 
+	dp_display_handle_plugged_change(g_dp_display,
+				dp->dp_display.is_connected);
+
+	DRM_DEBUG_DP("After, sink_count=%d is_connected=%d core_inited=%d power_on=%d\n",
+			dp->link->sink_count, dp->dp_display.is_connected,
+			dp->core_initialized, dp_display->power_on);
+
 	mutex_unlock(&dp->event_mutex);
 
 	return 0;
@@ -1326,6 +1337,9 @@ static int dp_pm_suspend(struct device *dev)
 
 	mutex_lock(&dp->event_mutex);
 
+	DRM_DEBUG_DP("Before, core_inited=%d power_on=%d\n",
+			dp->core_initialized, dp_display->power_on);
+
 	if (dp->core_initialized == true) {
 		/* mainlink enabled */
 		if (dp_power_clk_status(dp->power, DP_CTRL_PM))
@@ -1339,6 +1353,9 @@ static int dp_pm_suspend(struct device *dev)
 	/* host_init will be called at pm_resume */
 	dp->core_initialized = false;
 
+	DRM_DEBUG_DP("After, core_inited=%d power_on=%d\n",
+			dp->core_initialized, dp_display->power_on);
+
 	mutex_unlock(&dp->event_mutex);
 
 	return 0;
diff --git a/drivers/gpu/drm/msm/dp/dp_link.c b/drivers/gpu/drm/msm/dp/dp_link.c
index 1195044a7a3b..a5bdfc5029de 100644
--- a/drivers/gpu/drm/msm/dp/dp_link.c
+++ b/drivers/gpu/drm/msm/dp/dp_link.c
@@ -1027,43 +1027,29 @@ int dp_link_process_request(struct dp_link *dp_link)
 
 	if (link->request.test_requested == DP_TEST_LINK_EDID_READ) {
 		dp_link->sink_request |= DP_TEST_LINK_EDID_READ;
-		return ret;
-	}
-
-	ret = dp_link_process_ds_port_status_change(link);
-	if (!ret) {
+	} else if (!dp_link_process_ds_port_status_change(link)) {
 		dp_link->sink_request |= DS_PORT_STATUS_CHANGED;
-		return ret;
-	}
-
-	ret = dp_link_process_link_training_request(link);
-	if (!ret) {
+	} else if (!dp_link_process_link_training_request(link)) {
 		dp_link->sink_request |= DP_TEST_LINK_TRAINING;
-		return ret;
-	}
-
-	ret = dp_link_process_phy_test_pattern_request(link);
-	if (!ret) {
+	} else if (!dp_link_process_phy_test_pattern_request(link)) {
 		dp_link->sink_request |= DP_TEST_LINK_PHY_TEST_PATTERN;
-		return ret;
-	}
-
-	ret = dp_link_process_link_status_update(link);
-	if (!ret) {
-		dp_link->sink_request |= DP_LINK_STATUS_UPDATED;
-		return ret;
-	}
-
-	if (dp_link_is_video_pattern_requested(link)) {
-		ret = 0;
-		dp_link->sink_request |= DP_TEST_LINK_VIDEO_PATTERN;
-	}
-
-	if (dp_link_is_audio_pattern_requested(link)) {
-		dp_link->sink_request |= DP_TEST_LINK_AUDIO_PATTERN;
-		return -EINVAL;
+	} else {
+		ret = dp_link_process_link_status_update(link);
+		if (!ret) {
+			dp_link->sink_request |= DP_LINK_STATUS_UPDATED;
+		} else {
+			if (dp_link_is_video_pattern_requested(link)) {
+				ret = 0;
+				dp_link->sink_request |= DP_TEST_LINK_VIDEO_PATTERN;
+			}
+			if (dp_link_is_audio_pattern_requested(link)) {
+				dp_link->sink_request |= DP_TEST_LINK_AUDIO_PATTERN;
+				ret = -EINVAL;
+			}
+		}
 	}
 
+	DRM_DEBUG_DP("sink request=%#x", dp_link->sink_request);
 	return ret;
 }
 
diff --git a/drivers/gpu/drm/msm/dp/dp_panel.c b/drivers/gpu/drm/msm/dp/dp_panel.c
index 440b32753430..2181b60e1d1d 100644
--- a/drivers/gpu/drm/msm/dp/dp_panel.c
+++ b/drivers/gpu/drm/msm/dp/dp_panel.c
@@ -271,7 +271,7 @@ static u8 dp_panel_get_edid_checksum(struct edid *edid)
 {
 	struct edid *last_block;
 	u8 *raw_edid;
-	bool is_edid_corrupt;
+	bool is_edid_corrupt = false;
 
 	if (!edid) {
 		DRM_ERROR("invalid edid input\n");
@@ -303,7 +303,12 @@ void dp_panel_handle_sink_request(struct dp_panel *dp_panel)
 	panel = container_of(dp_panel, struct dp_panel_private, dp_panel);
 
 	if (panel->link->sink_request & DP_TEST_LINK_EDID_READ) {
-		u8 checksum = dp_panel_get_edid_checksum(dp_panel->edid);
+		u8 checksum;
+
+		if (dp_panel->edid)
+			checksum = dp_panel_get_edid_checksum(dp_panel->edid);
+		else
+			checksum = dp_panel->connector->real_edid_checksum;
 
 		dp_link_send_edid_checksum(panel->link, checksum);
 		dp_link_send_test_response(panel->link);
diff --git a/drivers/gpu/drm/msm/dp/dp_power.c b/drivers/gpu/drm/msm/dp/dp_power.c
index 3961ba4efc3c..b48b45e92bfa 100644
--- a/drivers/gpu/drm/msm/dp/dp_power.c
+++ b/drivers/gpu/drm/msm/dp/dp_power.c
@@ -208,6 +208,9 @@ static int dp_power_clk_set_rate(struct dp_power_private *power,
 
 int dp_power_clk_status(struct dp_power *dp_power, enum dp_pm_type pm_type)
 {
+	DRM_DEBUG_DP("core_clk_on=%d link_clk_on=%d stream_clk_on=%d\n",
+		dp_power->core_clks_on, dp_power->link_clks_on, dp_power->stream_clks_on);
+
 	if (pm_type == DP_CORE_PM)
 		return dp_power->core_clks_on;