[PATCH v4 3/4] drm: sun4i: dsi: Convert to bridge driver

[Jagan Teki <jagan@amarulasolutions.com>]

DRM bridge drivers have build-in handling of treating all display
pipeline components as bridges.

So, convert the existing to a drm bridge driver with a built-in
encoder support for compatibility with existing component drivers.

Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
---
Changes for v4:
- none
Changes for v3:
- new patch

 drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c | 75 ++++++++++++++++----------
 drivers/gpu/drm/sun4i/sun6i_mipi_dsi.h |  6 +++
 2 files changed, 54 insertions(+), 27 deletions(-)

diff --git a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
index 39321299dc27..6f3c5330a468 100644
--- a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
+++ b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
@@ -714,10 +714,10 @@ static int sun6i_dsi_start(struct sun6i_dsi *dsi,
 	return 0;
 }
 
-static void sun6i_dsi_encoder_enable(struct drm_encoder *encoder)
+static void sun6i_dsi_bridge_enable(struct drm_bridge *bridge)
 {
-	struct drm_display_mode *mode = &encoder->crtc->state->adjusted_mode;
-	struct sun6i_dsi *dsi = encoder_to_sun6i_dsi(encoder);
+	struct drm_display_mode *mode = &bridge->encoder->crtc->state->adjusted_mode;
+	struct sun6i_dsi *dsi = bridge_to_sun6i_dsi(bridge);
 	struct mipi_dsi_device *device = dsi->device;
 	union phy_configure_opts opts = { };
 	struct phy_configure_opts_mipi_dphy *cfg = &opts.mipi_dphy;
@@ -801,9 +801,9 @@ static void sun6i_dsi_encoder_enable(struct drm_encoder *encoder)
 	sun6i_dsi_start(dsi, DSI_START_HSD);
 }
 
-static void sun6i_dsi_encoder_disable(struct drm_encoder *encoder)
+static void sun6i_dsi_bridge_disable(struct drm_bridge *bridge)
 {
-	struct sun6i_dsi *dsi = encoder_to_sun6i_dsi(encoder);
+	struct sun6i_dsi *dsi = bridge_to_sun6i_dsi(bridge);
 
 	DRM_DEBUG_DRIVER("Disabling DSI output\n");
 
@@ -852,9 +852,40 @@ static const struct drm_connector_funcs sun6i_dsi_connector_funcs = {
 	.atomic_destroy_state	= drm_atomic_helper_connector_destroy_state,
 };
 
-static const struct drm_encoder_helper_funcs sun6i_dsi_enc_helper_funcs = {
-	.disable	= sun6i_dsi_encoder_disable,
-	.enable		= sun6i_dsi_encoder_enable,
+static int sun6i_dsi_bridge_attach(struct drm_bridge *bridge,
+				   enum drm_bridge_attach_flags flags)
+{
+	struct sun6i_dsi *dsi = bridge_to_sun6i_dsi(bridge);
+	int ret;
+
+	if (dsi->panel_bridge)
+		return drm_bridge_attach(bridge->encoder, dsi->panel_bridge, NULL, 0);
+
+	if (dsi->panel) {
+		drm_connector_helper_add(&dsi->connector,
+					 &sun6i_dsi_connector_helper_funcs);
+		ret = drm_connector_init(bridge->dev, &dsi->connector,
+					 &sun6i_dsi_connector_funcs,
+					 DRM_MODE_CONNECTOR_DSI);
+		if (ret) {
+			dev_err(dsi->dev, "Couldn't initialise the DSI connector\n");
+			goto err_cleanup_connector;
+		}
+
+		drm_connector_attach_encoder(&dsi->connector, &dsi->encoder);
+	}
+
+	return 0;
+
+err_cleanup_connector:
+	drm_encoder_cleanup(&dsi->encoder);
+	return ret;
+}
+
+static const struct drm_bridge_funcs sun6i_dsi_bridge_funcs = {
+	.enable		= sun6i_dsi_bridge_enable,
+	.disable	= sun6i_dsi_bridge_disable,
+	.attach		= sun6i_dsi_bridge_attach,
 };
 
 static u32 sun6i_dsi_dcs_build_pkt_hdr(struct sun6i_dsi *dsi,
@@ -1063,8 +1094,6 @@ static int sun6i_dsi_bind(struct device *dev, struct device *master,
 	struct sun6i_dsi *dsi = dev_get_drvdata(dev);
 	int ret;
 
-	drm_encoder_helper_add(&dsi->encoder,
-			       &sun6i_dsi_enc_helper_funcs);
 	ret = drm_simple_encoder_init(drm, &dsi->encoder,
 				      DRM_MODE_ENCODER_DSI);
 	if (ret) {
@@ -1073,27 +1102,12 @@ static int sun6i_dsi_bind(struct device *dev, struct device *master,
 	}
 	dsi->encoder.possible_crtcs = BIT(0);
 
-	drm_connector_helper_add(&dsi->connector,
-				 &sun6i_dsi_connector_helper_funcs);
-	ret = drm_connector_init(drm, &dsi->connector,
-				 &sun6i_dsi_connector_funcs,
-				 DRM_MODE_CONNECTOR_DSI);
+	ret = drm_bridge_attach(&dsi->encoder, &dsi->bridge, NULL, 0);
 	if (ret) {
-		dev_err(dsi->dev,
-			"Couldn't initialise the DSI connector\n");
+		dev_err(dsi->dev, "Couldn't attach drm bridge\n");
 		goto err_cleanup_connector;
 	}
 
-	drm_connector_attach_encoder(&dsi->connector, &dsi->encoder);
-
-	if (dsi->panel_bridge) {
-		ret = drm_bridge_attach(&dsi->encoder, dsi->panel_bridge, NULL, 0);
-		if (ret) {
-			dev_err(dsi->dev, "Couldn't attach drm bridge\n");
-			goto err_cleanup_connector;
-		}
-	}
-
 	return 0;
 
 err_cleanup_connector:
@@ -1199,6 +1213,12 @@ static int sun6i_dsi_probe(struct platform_device *pdev)
 		goto err_unprotect_clk;
 	}
 
+	dsi->bridge.funcs = &sun6i_dsi_bridge_funcs;
+	dsi->bridge.of_node = dev->of_node;
+	dsi->bridge.type = DRM_MODE_CONNECTOR_DSI;
+
+	drm_bridge_add(&dsi->bridge);
+
 	ret = component_add(&pdev->dev, &sun6i_dsi_ops);
 	if (ret) {
 		dev_err(dev, "Couldn't register our component\n");
@@ -1222,6 +1242,7 @@ static int sun6i_dsi_remove(struct platform_device *pdev)
 	struct device *dev = &pdev->dev;
 	struct sun6i_dsi *dsi = dev_get_drvdata(dev);
 
+	drm_bridge_remove(&dsi->bridge);
 	component_del(&pdev->dev, &sun6i_dsi_ops);
 	mipi_dsi_host_unregister(&dsi->host);
 	clk_rate_exclusive_put(dsi->mod_clk);
diff --git a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.h b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.h
index 370ecb356a63..5e70666089ad 100644
--- a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.h
+++ b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.h
@@ -16,6 +16,7 @@
 #define SUN6I_DSI_TCON_DIV	4
 
 struct sun6i_dsi {
+	struct drm_bridge	bridge;
 	struct drm_connector	connector;
 	struct drm_encoder	encoder;
 	struct mipi_dsi_host	host;
@@ -38,6 +39,11 @@ static inline struct sun6i_dsi *host_to_sun6i_dsi(struct mipi_dsi_host *host)
 	return container_of(host, struct sun6i_dsi, host);
 };
 
+static inline struct sun6i_dsi *bridge_to_sun6i_dsi(struct drm_bridge *bridge)
+{
+	return container_of(bridge, struct sun6i_dsi, bridge);
+}
+
 static inline struct sun6i_dsi *connector_to_sun6i_dsi(struct drm_connector *connector)
 {
 	return container_of(connector, struct sun6i_dsi, connector);
-- 
2.25.1