drm/mediatek: mtk_dpi: Convert to bridge driver

Convert mtk_dpi to a bridge driver with built-in encoder support for
compatibility with existing component drivers.

Signed-off-by: Enric Balletbo i Serra <[e-mail]>
Signed-off-by: Chun-Kuang Hu <[e-mail]>

drivers/gpu/drm/mediatek/mtk_dpi.c

···
 struct mtk_dpi {
 	struct mtk_ddp_comp ddp_comp;
 	struct drm_encoder encoder;
+	struct drm_bridge bridge;
 	struct drm_bridge *next_bridge;
 	void __iomem *regs;
 	struct device *dev;
···
 	int refcount;
 };
 
-static inline struct mtk_dpi *mtk_dpi_from_encoder(struct drm_encoder *e)
+static inline struct mtk_dpi *bridge_to_dpi(struct drm_bridge *b)
 {
-	return container_of(e, struct mtk_dpi, encoder);
+	return container_of(b, struct mtk_dpi, bridge);
 }
 
 enum mtk_dpi_polarity {
···
 	return 0;
 }
 
-static bool mtk_dpi_encoder_mode_fixup(struct drm_encoder *encoder,
-				       const struct drm_display_mode *mode,
-				       struct drm_display_mode *adjusted_mode)
+static void mtk_dpi_encoder_destroy(struct drm_encoder *encoder)
 {
-	return true;
+	drm_encoder_cleanup(encoder);
 }
 
-static void mtk_dpi_encoder_mode_set(struct drm_encoder *encoder,
-				     struct drm_display_mode *mode,
-				     struct drm_display_mode *adjusted_mode)
+static const struct drm_encoder_funcs mtk_dpi_encoder_funcs = {
+	.destroy = mtk_dpi_encoder_destroy,
+};
+
+static int mtk_dpi_bridge_attach(struct drm_bridge *bridge,
+				 enum drm_bridge_attach_flags flags)
 {
-	struct mtk_dpi *dpi = mtk_dpi_from_encoder(encoder);
+	struct mtk_dpi *dpi = bridge_to_dpi(bridge);
+
+	return drm_bridge_attach(bridge->encoder, dpi->next_bridge,
+				 &dpi->bridge, flags);
+}
+
+static void mtk_dpi_bridge_mode_set(struct drm_bridge *bridge,
+				const struct drm_display_mode *mode,
+				const struct drm_display_mode *adjusted_mode)
+{
+	struct mtk_dpi *dpi = bridge_to_dpi(bridge);
 
 	drm_mode_copy(&dpi->mode, adjusted_mode);
 }
 
-static void mtk_dpi_encoder_disable(struct drm_encoder *encoder)
+static void mtk_dpi_bridge_disable(struct drm_bridge *bridge)
 {
-	struct mtk_dpi *dpi = mtk_dpi_from_encoder(encoder);
+	struct mtk_dpi *dpi = bridge_to_dpi(bridge);
 
 	mtk_dpi_power_off(dpi);
 }
 
-static void mtk_dpi_encoder_enable(struct drm_encoder *encoder)
+static void mtk_dpi_bridge_enable(struct drm_bridge *bridge)
 {
-	struct mtk_dpi *dpi = mtk_dpi_from_encoder(encoder);
+	struct mtk_dpi *dpi = bridge_to_dpi(bridge);
 
 	mtk_dpi_power_on(dpi);
 	mtk_dpi_set_display_mode(dpi, &dpi->mode);
 }
 
-static int mtk_dpi_atomic_check(struct drm_encoder *encoder,
-				struct drm_crtc_state *crtc_state,
-				struct drm_connector_state *conn_state)
-{
-	return 0;
-}
-
-static const struct drm_encoder_helper_funcs mtk_dpi_encoder_helper_funcs = {
-	.mode_fixup = mtk_dpi_encoder_mode_fixup,
-	.mode_set = mtk_dpi_encoder_mode_set,
-	.disable = mtk_dpi_encoder_disable,
-	.enable = mtk_dpi_encoder_enable,
-	.atomic_check = mtk_dpi_atomic_check,
+static const struct drm_bridge_funcs mtk_dpi_bridge_funcs = {
+	.attach = mtk_dpi_bridge_attach,
+	.mode_set = mtk_dpi_bridge_mode_set,
+	.disable = mtk_dpi_bridge_disable,
+	.enable = mtk_dpi_bridge_enable,
 };
 
 static void mtk_dpi_start(struct mtk_ddp_comp *comp)
···
 		dev_err(dev, "Failed to initialize decoder: %d\n", ret);
 		goto err_unregister;
 	}
-	drm_encoder_helper_add(&dpi->encoder, &mtk_dpi_encoder_helper_funcs);
 
 	dpi->encoder.possible_crtcs = mtk_drm_find_possible_crtc_by_comp(drm_dev, dpi->ddp_comp);
 
-	ret = drm_bridge_attach(&dpi->encoder, dpi->next_bridge, NULL, 0);
+	ret = drm_bridge_attach(&dpi->encoder, &dpi->bridge, NULL, 0);
 	if (ret) {
 		dev_err(dev, "Failed to attach bridge: %d\n", ret);
 		goto err_cleanup;
···
 
 	platform_set_drvdata(pdev, dpi);
 
+	dpi->bridge.funcs = &mtk_dpi_bridge_funcs;
+	dpi->bridge.of_node = dev->of_node;
+	dpi->bridge.type = DRM_MODE_CONNECTOR_DPI;
+
+	drm_bridge_add(&dpi->bridge);
+
 	ret = component_add(dev, &mtk_dpi_component_ops);
 	if (ret) {
+		drm_bridge_remove(&dpi->bridge);
 		dev_err(dev, "Failed to add component: %d\n", ret);
 		return ret;
 	}
···
 
 static int mtk_dpi_remove(struct platform_device *pdev)
 {
+	struct mtk_dpi *dpi = platform_get_drvdata(pdev);
+
 	component_del(&pdev->dev, &mtk_dpi_component_ops);
+	drm_bridge_remove(&dpi->bridge);
 
 	return 0;
 }