drm/msm/dsi-staging: update ESD thread disable sequence

Currently to synchronize ESD check and DSI disable, ESD
thread acquires display mutex before the check starts.
But this is causing performance issues when atomic check
also tries to acquire the display mutex and blocks on ESD
thread if the later has already acquired it.
Fix this race condition by removing display mutex lock from
ESD thread and instead synchronize ESD check and DSI disable
by always ensuring that ESD check has been stopped before
DSI disable sequence kicks in.

Change-Id: I5a0b44a7cbf01648303eb85c7a08a6a62c1ef94e
Signed-off-by: Sandeep Panda <spanda@codeaurora.org>
Signed-off-by: Shashank Babu Chinta Venkata <sbchin@codeaurora.org>

drivers/gpu/drm/msm/dsi-staging/dsi_display.c

@@ -555,9 +555,6 @@ static int dsi_display_read_status(struct dsi_display_ctrl *ctrl,
 	if (dsi_ctrl_validate_host_state(ctrl->ctrl))
 		return 1;
 
-	/* acquire panel_lock to make sure no commands are in progress */
-	dsi_panel_acquire_panel_lock(panel);
-
 	config = &(panel->esd_config);
 	lenp = config->status_valid_params ?: config->status_cmds_rlen;
 	count = config->status_cmd.count;
@@ -575,7 +572,7 @@ static int dsi_display_read_status(struct dsi_display_ctrl *ctrl,
 		rc = dsi_ctrl_cmd_transfer(ctrl->ctrl, &cmds[i].msg, flags);
 		if (rc <= 0) {
 			pr_err("rx cmd transfer failed rc=%d\n", rc);
-			goto error;
+			return rc;
 		}
 
 		memcpy(config->return_buf + start,
@@ -583,9 +580,6 @@ static int dsi_display_read_status(struct dsi_display_ctrl *ctrl,
 		start += lenp[i];
 	}
 
-error:
-	/* release panel_lock */
-	dsi_panel_release_panel_lock(panel);
 	return rc;
 }
 
@@ -705,15 +699,16 @@ int dsi_display_check_status(struct drm_connector *connector, void *display,
 	u32 status_mode;
 	int rc = 0x1;
 
-	if (dsi_display == NULL)
+	if (!dsi_display || !dsi_display->panel)
 		return -EINVAL;
 
-	mutex_lock(&dsi_display->display_lock);
-
 	panel = dsi_display->panel;
+
+	dsi_panel_acquire_panel_lock(panel);
+
 	if (!panel->panel_initialized) {
 		pr_debug("Panel not initialized\n");
-		mutex_unlock(&dsi_display->display_lock);
+		dsi_panel_release_panel_lock(panel);
 		return rc;
 	}
 
@@ -738,7 +733,7 @@ int dsi_display_check_status(struct drm_connector *connector, void *display,
 
 	dsi_display_clk_ctrl(dsi_display->dsi_clk_handle,
 		DSI_ALL_CLKS, DSI_CLK_OFF);
-	mutex_unlock(&dsi_display->display_lock);
+	dsi_panel_release_panel_lock(panel);
 
 	return rc;
 }

drivers/gpu/drm/msm/sde/sde_connector.c

@@ -655,6 +655,9 @@ void sde_connector_helper_bridge_disable(struct drm_connector *connector)
 		SDE_EVT32(connector->base.id, SDE_EVTLOG_ERROR);
 	}
 
+	/* Disable ESD thread */
+	sde_connector_schedule_status_work(connector, false);
+
 	c_conn = to_sde_connector(connector);
 	if (c_conn->panel_dead) {
 		c_conn->bl_device->props.power = FB_BLANK_POWERDOWN;

drivers/gpu/drm/msm/sde/sde_encoder.c

@@ -3002,7 +3002,6 @@ static void sde_encoder_virt_disable(struct drm_encoder *drm_enc)
 	struct sde_encoder_virt *sde_enc = NULL;
 	struct msm_drm_private *priv;
 	struct sde_kms *sde_kms;
-	struct drm_connector *drm_conn = NULL;
 	enum sde_intf_mode intf_mode;
 	int i = 0;
 
@@ -3031,10 +3030,6 @@ static void sde_encoder_virt_disable(struct drm_encoder *drm_enc)
 
 	SDE_EVT32(DRMID(drm_enc));
 
-	/* Disable ESD thread */
-	drm_conn = sde_enc->cur_master->connector;
-	sde_connector_schedule_status_work(drm_conn, false);
-
 	/* wait for idle */
 	sde_encoder_wait_for_event(drm_enc, MSM_ENC_TX_COMPLETE);