drm/exynos: do not start enabling DP at bind() phase

The DP device will be properly enabled at the enable() call just
after the bind call finishes.

Changelog v2:
- no change

Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Signed-off-by: Inki Dae <inki.dae@samsung.com>

drivers/gpu/drm/exynos/exynos_dp_core.c

@@ -1009,9 +1009,9 @@ static int exynos_drm_attach_lcd_bridge(struct exynos_dp_device *dp,
 {
 	int ret;
 
-	encoder->bridge = dp->bridge;
+	encoder->bridge->next = dp->ptn_bridge;
-	dp->bridge->encoder = encoder;
+	dp->ptn_bridge->encoder = encoder;
-	ret = drm_bridge_attach(encoder->dev, dp->bridge);
+	ret = drm_bridge_attach(encoder->dev, dp->ptn_bridge);
 	if (ret) {
 		DRM_ERROR("Failed to attach bridge to drm\n");
 		return ret;
@@ -1020,14 +1020,15 @@ static int exynos_drm_attach_lcd_bridge(struct exynos_dp_device *dp,
 	return 0;
 }
 
-static int exynos_dp_create_connector(struct drm_encoder *encoder)
+static int exynos_dp_bridge_attach(struct drm_bridge *bridge)
 {
-	struct exynos_dp_device *dp = encoder_to_dp(encoder);
+	struct exynos_dp_device *dp = bridge->driver_private;
+	struct drm_encoder *encoder = &dp->encoder;
 	struct drm_connector *connector = &dp->connector;
 	int ret;
 
 	/* Pre-empt DP connector creation if there's a bridge */
-	if (dp->bridge) {
+	if (dp->ptn_bridge) {
 		ret = exynos_drm_attach_lcd_bridge(dp, encoder);
 		if (!ret)
 			return 0;
@@ -1052,22 +1053,9 @@ static int exynos_dp_create_connector(struct drm_encoder *encoder)
 	return ret;
 }
 
-static bool exynos_dp_mode_fixup(struct drm_encoder *encoder,
+static void exynos_dp_bridge_enable(struct drm_bridge *bridge)
-				 const struct drm_display_mode *mode,
-				 struct drm_display_mode *adjusted_mode)
 {
-	return true;
+	struct exynos_dp_device *dp = bridge->driver_private;
-}
-
-static void exynos_dp_mode_set(struct drm_encoder *encoder,
-			       struct drm_display_mode *mode,
-			       struct drm_display_mode *adjusted_mode)
-{
-}
-
-static void exynos_dp_enable(struct drm_encoder *encoder)
-{
-	struct exynos_dp_device *dp = encoder_to_dp(encoder);
 	struct exynos_drm_crtc *crtc = dp_to_crtc(dp);
 
 	if (dp->dpms_mode == DRM_MODE_DPMS_ON)
@@ -1092,9 +1080,9 @@ static void exynos_dp_enable(struct drm_encoder *encoder)
 	dp->dpms_mode = DRM_MODE_DPMS_ON;
 }
 
-static void exynos_dp_disable(struct drm_encoder *encoder)
+static void exynos_dp_bridge_disable(struct drm_bridge *bridge)
 {
-	struct exynos_dp_device *dp = encoder_to_dp(encoder);
+	struct exynos_dp_device *dp = bridge->driver_private;
 	struct exynos_drm_crtc *crtc = dp_to_crtc(dp);
 
 	if (dp->dpms_mode != DRM_MODE_DPMS_ON)
@@ -1123,6 +1111,69 @@ static void exynos_dp_disable(struct drm_encoder *encoder)
 	dp->dpms_mode = DRM_MODE_DPMS_OFF;
 }
 
+static void exynos_dp_bridge_nop(struct drm_bridge *bridge)
+{
+	/* do nothing */
+}
+
+static const struct drm_bridge_funcs exynos_dp_bridge_funcs = {
+	.enable = exynos_dp_bridge_enable,
+	.disable = exynos_dp_bridge_disable,
+	.pre_enable = exynos_dp_bridge_nop,
+	.post_disable = exynos_dp_bridge_nop,
+	.attach = exynos_dp_bridge_attach,
+};
+
+static int exynos_dp_create_connector(struct drm_encoder *encoder)
+{
+	struct exynos_dp_device *dp = encoder_to_dp(encoder);
+	struct drm_device *drm_dev = dp->drm_dev;
+	struct drm_bridge *bridge;
+	int ret;
+
+	bridge = devm_kzalloc(drm_dev->dev, sizeof(*bridge), GFP_KERNEL);
+	if (!bridge) {
+		DRM_ERROR("failed to allocate for drm bridge\n");
+		return -ENOMEM;
+	}
+
+	dp->bridge = bridge;
+
+	encoder->bridge = bridge;
+	bridge->driver_private = dp;
+	bridge->encoder = encoder;
+	bridge->funcs = &exynos_dp_bridge_funcs;
+
+	ret = drm_bridge_attach(drm_dev, bridge);
+	if (ret) {
+		DRM_ERROR("failed to attach drm bridge\n");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static bool exynos_dp_mode_fixup(struct drm_encoder *encoder,
+				 const struct drm_display_mode *mode,
+				 struct drm_display_mode *adjusted_mode)
+{
+	return true;
+}
+
+static void exynos_dp_mode_set(struct drm_encoder *encoder,
+			       struct drm_display_mode *mode,
+			       struct drm_display_mode *adjusted_mode)
+{
+}
+
+static void exynos_dp_enable(struct drm_encoder *encoder)
+{
+}
+
+static void exynos_dp_disable(struct drm_encoder *encoder)
+{
+}
+
 static struct drm_encoder_helper_funcs exynos_dp_encoder_helper_funcs = {
 	.mode_fixup = exynos_dp_mode_fixup,
 	.mode_set = exynos_dp_mode_set,
@@ -1238,7 +1289,7 @@ static int exynos_dp_bind(struct device *dev, struct device *master, void *data)
 		}
 	}
 
-	if (!dp->panel && !dp->bridge) {
+	if (!dp->panel && !dp->ptn_bridge) {
 		ret = exynos_dp_dt_parse_panel(dp);
 		if (ret)
 			return ret;
@@ -1289,10 +1340,6 @@ static int exynos_dp_bind(struct device *dev, struct device *master, void *data)
 
 	INIT_WORK(&dp->hotplug_work, exynos_dp_hotplug);
 
-	phy_power_on(dp->phy);
-
-	exynos_dp_init_dp(dp);
-
 	ret = devm_request_irq(&pdev->dev, dp->irq, exynos_dp_irq_handler,
 			irq_flags, "exynos-dp", dp);
 	if (ret) {
@@ -1365,9 +1412,9 @@ static int exynos_dp_probe(struct platform_device *pdev)
 	if (endpoint) {
 		bridge_node = of_graph_get_remote_port_parent(endpoint);
 		if (bridge_node) {
-			dp->bridge = of_drm_find_bridge(bridge_node);
+			dp->ptn_bridge = of_drm_find_bridge(bridge_node);
 			of_node_put(bridge_node);
-			if (!dp->bridge)
+			if (!dp->ptn_bridge)
 				return -EPROBE_DEFER;
 		} else
 			return -EPROBE_DEFER;

drivers/gpu/drm/exynos/exynos_dp_core.h

@@ -153,6 +153,7 @@ struct exynos_dp_device {
 	struct drm_connector	connector;
 	struct drm_panel	*panel;
 	struct drm_bridge	*bridge;
+	struct drm_bridge	*ptn_bridge;
 	struct clk		*clock;
 	unsigned int		irq;
 	void __iomem		*reg_base;