4 files changed, 90 insertions, 8 deletions

diff --git a/drivers/gpu/drm/msm/dsi/dsi.c b/drivers/gpu/drm/msm/dsi/dsi.c
index ffaf77f623c6..6edcd6f57e70 100644
--- a/drivers/gpu/drm/msm/dsi/dsi.c
+++ b/drivers/gpu/drm/msm/dsi/dsi.c
@@ -190,6 +190,7 @@ int msm_dsi_modeset_init(struct msm_dsi *msm_dsi, struct drm_device *dev,
 		struct drm_encoder *encoders[MSM_DSI_ENCODER_NUM])
 {
 	struct msm_drm_private *priv = dev->dev_private;
+	struct drm_bridge *ext_bridge;
 	int ret, i;
 
 	if (WARN_ON(!encoders[MSM_DSI_VIDEO_ENCODER_ID] ||
@@ -217,10 +218,25 @@ int msm_dsi_modeset_init(struct msm_dsi *msm_dsi, struct drm_device *dev,
 		msm_dsi->encoders[i] = encoders[i];
 	}
 
-	msm_dsi->connector = msm_dsi_manager_connector_init(msm_dsi->id);
+	/*
+	 * check if the dsi encoder output is connected to a panel or an
+	 * external bridge. We create a connector only if we're connected to a
+	 * drm_panel device. When we're connected to an external bridge, we
+	 * assume that the drm_bridge driver will create the connector itself.
+	 */
+	ext_bridge = msm_dsi_host_get_bridge(msm_dsi->host);
+
+	if (ext_bridge)
+		msm_dsi->connector =
+			msm_dsi_manager_ext_bridge_init(msm_dsi->id);
+	else
+		msm_dsi->connector =
+			msm_dsi_manager_connector_init(msm_dsi->id);
+
 	if (IS_ERR(msm_dsi->connector)) {
 		ret = PTR_ERR(msm_dsi->connector);
-		dev_err(dev->dev, "failed to create dsi connector: %d\n", ret);
+		dev_err(dev->dev,
+			"failed to create dsi connector: %d\n", ret);
 		msm_dsi->connector = NULL;
 		goto fail;
 	}
@@ -236,10 +252,12 @@ fail:
 			msm_dsi_manager_bridge_destroy(msm_dsi->bridge);
 			msm_dsi->bridge = NULL;
 		}
-		if (msm_dsi->connector) {
+
+		/* don't destroy connector if we didn't make it */
+		if (msm_dsi->connector && !msm_dsi->external_bridge)
 			msm_dsi->connector->funcs->destroy(msm_dsi->connector);
-			msm_dsi->connector = NULL;
-		}
+
+		msm_dsi->connector = NULL;
 	}
 
 	return ret;
diff --git a/drivers/gpu/drm/msm/dsi/dsi.h b/drivers/gpu/drm/msm/dsi/dsi.h
index 1636513347e0..09492bfc0e02 100644
--- a/drivers/gpu/drm/msm/dsi/dsi.h
+++ b/drivers/gpu/drm/msm/dsi/dsi.h
@@ -54,12 +54,20 @@ struct msm_dsi {
 	struct drm_device *dev;
 	struct platform_device *pdev;
 
+	/* connector managed by us when we're connected to a drm_panel */
 	struct drm_connector *connector;
+	/* internal dsi bridge attached to MDP interface */
 	struct drm_bridge *bridge;
 
 	struct mipi_dsi_host *host;
 	struct msm_dsi_phy *phy;
+
+	/*
+	 * panel/external_bridge connected to dsi bridge output, only one of the
+	 * two can be valid at a time
+	 */
 	struct drm_panel *panel;
+	struct drm_bridge *external_bridge;
 	unsigned long device_flags;
 
 	struct device *phy_dev;
@@ -75,6 +83,7 @@ struct msm_dsi {
 struct drm_bridge *msm_dsi_manager_bridge_init(u8 id);
 void msm_dsi_manager_bridge_destroy(struct drm_bridge *bridge);
 struct drm_connector *msm_dsi_manager_connector_init(u8 id);
+struct drm_connector *msm_dsi_manager_ext_bridge_init(u8 id);
 int msm_dsi_manager_phy_enable(int id,
 		const unsigned long bit_rate, const unsigned long esc_rate,
 		u32 *clk_pre, u32 *clk_post);
@@ -87,7 +96,7 @@ void msm_dsi_manager_unregister(struct msm_dsi *msm_dsi);
 /* msm dsi */
 static inline bool msm_dsi_device_connected(struct msm_dsi *msm_dsi)
 {
-	return msm_dsi->panel;
+	return msm_dsi->panel || msm_dsi->external_bridge;
 }
 
 struct drm_encoder *msm_dsi_get_encoder(struct msm_dsi *msm_dsi);
@@ -143,6 +152,7 @@ int msm_dsi_host_set_display_mode(struct mipi_dsi_host *host,
 					struct drm_display_mode *mode);
 struct drm_panel *msm_dsi_host_get_panel(struct mipi_dsi_host *host,
 					unsigned long *panel_flags);
+struct drm_bridge *msm_dsi_host_get_bridge(struct mipi_dsi_host *host);
 int msm_dsi_host_register(struct mipi_dsi_host *host, bool check_defer);
 void msm_dsi_host_unregister(struct mipi_dsi_host *host);
 int msm_dsi_host_set_src_pll(struct mipi_dsi_host *host,
diff --git a/drivers/gpu/drm/msm/dsi/dsi_host.c b/drivers/gpu/drm/msm/dsi/dsi_host.c
index 0fa55354ad2c..af40d428ff44 100644
--- a/drivers/gpu/drm/msm/dsi/dsi_host.c
+++ b/drivers/gpu/drm/msm/dsi/dsi_host.c
@@ -1646,7 +1646,8 @@ int msm_dsi_host_register(struct mipi_dsi_host *host, bool check_defer)
 		 */
 		if (check_defer && msm_host->device_node) {
 			if (!of_drm_find_panel(msm_host->device_node))
-				return -EPROBE_DEFER;
+				if (!of_drm_find_bridge(msm_host->device_node))
+					return -EPROBE_DEFER;
 		}
 	}
 
@@ -2073,3 +2074,9 @@ struct drm_panel *msm_dsi_host_get_panel(struct mipi_dsi_host *host,
 	return panel;
 }
 
+struct drm_bridge *msm_dsi_host_get_bridge(struct mipi_dsi_host *host)
+{
+	struct msm_dsi_host *msm_host = to_msm_dsi_host(host);
+
+	return of_drm_find_bridge(msm_host->device_node);
+}
diff --git a/drivers/gpu/drm/msm/dsi/dsi_manager.c b/drivers/gpu/drm/msm/dsi/dsi_manager.c
index 60dbd829d7a9..dc3d322375e9 100644
--- a/drivers/gpu/drm/msm/dsi/dsi_manager.c
+++ b/drivers/gpu/drm/msm/dsi/dsi_manager.c
@@ -517,7 +517,7 @@ static const struct drm_bridge_funcs dsi_mgr_bridge_funcs = {
 	.mode_set = dsi_mgr_bridge_mode_set,
 };
 
-/* initialize connector */
+/* initialize connector when we're connected to a drm_panel */
 struct drm_connector *msm_dsi_manager_connector_init(u8 id)
 {
 	struct msm_dsi *msm_dsi = dsi_mgr_get_dsi(id);
@@ -602,6 +602,53 @@ fail:
 	return ERR_PTR(ret);
 }
 
+struct drm_connector *msm_dsi_manager_ext_bridge_init(u8 id)
+{
+	struct msm_dsi *msm_dsi = dsi_mgr_get_dsi(id);
+	struct drm_device *dev = msm_dsi->dev;
+	struct drm_encoder *encoder;
+	struct drm_bridge *int_bridge, *ext_bridge;
+	struct drm_connector *connector;
+	struct list_head *connector_list;
+
+	int_bridge = msm_dsi->bridge;
+	ext_bridge = msm_dsi->external_bridge =
+			msm_dsi_host_get_bridge(msm_dsi->host);
+
+	/*
+	 * HACK: we may not know the external DSI bridge device's mode
+	 * flags here. We'll get to know them only when the device
+	 * attaches to the dsi host. For now, assume the bridge supports
+	 * DSI video mode
+	 */
+	encoder = msm_dsi->encoders[MSM_DSI_VIDEO_ENCODER_ID];
+
+	/* link the internal dsi bridge to the external bridge */
+	int_bridge->next = ext_bridge;
+	/* set the external bridge's encoder as dsi's encoder */
+	ext_bridge->encoder = encoder;
+
+	drm_bridge_attach(dev, ext_bridge);
+
+	/*
+	 * we need the drm_connector created by the external bridge
+	 * driver (or someone else) to feed it to our driver's
+	 * priv->connector[] list, mainly for msm_fbdev_init()
+	 */
+	connector_list = &dev->mode_config.connector_list;
+
+	list_for_each_entry(connector, connector_list, head) {
+		int i;
+
+		for (i = 0; i < DRM_CONNECTOR_MAX_ENCODER; i++) {
+			if (connector->encoder_ids[i] == encoder->base.id)
+				return connector;
+		}
+	}
+
+	return ERR_PTR(-ENODEV);
+}
+
 void msm_dsi_manager_bridge_destroy(struct drm_bridge *bridge)
 {
 }