drm: bridge: dw-hdmi: Implement DRM bridge registration

As an option for drivers not based on the component framework, register
the bridge with the DRM core with the DRM bridge API. Existing drivers
based on dw_hdmi_bind() and dw_hdmi_unbind() are not affected as those
functions are preserved with their current behaviour.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Reviewed-by: Jose Abreu <joabreu@synopsys.com>
Signed-off-by: Archit Taneja <architt@codeaurora.org>
Link: http://patchwork.freedesktop.org/patch/msgid/20170117082910.27023-11-laurent.pinchart+renesas@ideasonboard.com

drivers/gpu/drm/bridge/dw-hdmi.c

@@ -1836,23 +1836,8 @@ static irqreturn_t dw_hdmi_irq(int irq, void *dev_id)
 	return IRQ_HANDLED;
 }
 
-static int dw_hdmi_register(struct drm_encoder *encoder, struct dw_hdmi *hdmi)
-{
-	struct drm_bridge *bridge = &hdmi->bridge;
-	int ret;
-
-	bridge->driver_private = hdmi;
-	bridge->funcs = &dw_hdmi_bridge_funcs;
-	ret = drm_bridge_attach(encoder, bridge, NULL);
-	if (ret) {
-		DRM_ERROR("Failed to initialize bridge with drm\n");
-		return -EINVAL;
-	}
-
-	return 0;
-}
-
-int dw_hdmi_bind(struct platform_device *pdev, struct drm_encoder *encoder,
+static struct dw_hdmi *
+__dw_hdmi_probe(struct platform_device *pdev,
 		const struct dw_hdmi_plat_data *plat_data)
 {
 	struct device *dev = &pdev->dev;
@@ -1869,7 +1854,7 @@ int dw_hdmi_bind(struct platform_device *pdev, struct drm_encoder *encoder,
 
 	hdmi = devm_kzalloc(dev, sizeof(*hdmi), GFP_KERNEL);
 	if (!hdmi)
-		return -ENOMEM;
+		return ERR_PTR(-ENOMEM);
 
 	hdmi->plat_data = plat_data;
 	hdmi->dev = dev;
@@ -1896,7 +1881,7 @@ int dw_hdmi_bind(struct platform_device *pdev, struct drm_encoder *encoder,
 		break;
 	default:
 		dev_err(dev, "reg-io-width must be 1 or 4\n");
-		return -EINVAL;
+		return ERR_PTR(-EINVAL);
 	}
 
 	ddc_node = of_parse_phandle(np, "ddc-i2c-bus", 0);
@@ -1905,7 +1890,7 @@ int dw_hdmi_bind(struct platform_device *pdev, struct drm_encoder *encoder,
 		of_node_put(ddc_node);
 		if (!hdmi->ddc) {
 			dev_dbg(hdmi->dev, "failed to read ddc node\n");
-			return -EPROBE_DEFER;
+			return ERR_PTR(-EPROBE_DEFER);
 		}
 
 	} else {
@@ -1956,8 +1941,10 @@ int dw_hdmi_bind(struct platform_device *pdev, struct drm_encoder *encoder,
 	initialize_hdmi_ih_mutes(hdmi);
 
 	irq = platform_get_irq(pdev, 0);
-	if (irq < 0)
+	if (irq < 0) {
+		ret = irq;
 		goto err_iahb;
+	}
 
 	ret = devm_request_threaded_irq(dev, irq, dw_hdmi_hardirq,
 					dw_hdmi_irq, IRQF_SHARED,
@@ -1988,11 +1975,11 @@ int dw_hdmi_bind(struct platform_device *pdev, struct drm_encoder *encoder,
 	hdmi_writeb(hdmi, HDMI_IH_PHY_STAT0_HPD | HDMI_IH_PHY_STAT0_RX_SENSE,
 		    HDMI_IH_PHY_STAT0);
 
-	ret = dw_hdmi_fb_registered(hdmi);
-	if (ret)
-		goto err_iahb;
+	hdmi->bridge.driver_private = hdmi;
+	hdmi->bridge.funcs = &dw_hdmi_bridge_funcs;
+	hdmi->bridge.of_node = pdev->dev.of_node;
 
-	ret = dw_hdmi_register(encoder, hdmi);
+	ret = dw_hdmi_fb_registered(hdmi);
 	if (ret)
 		goto err_iahb;
 
@@ -2041,7 +2028,7 @@ int dw_hdmi_bind(struct platform_device *pdev, struct drm_encoder *encoder,
 
 	platform_set_drvdata(pdev, hdmi);
 
-	return 0;
+	return hdmi;
 
 err_iahb:
 	if (hdmi->i2c) {
@@ -2055,14 +2042,11 @@ int dw_hdmi_bind(struct platform_device *pdev, struct drm_encoder *encoder,
 err_res:
 	i2c_put_adapter(hdmi->ddc);
 
-	return ret;
+	return ERR_PTR(ret);
 }
-EXPORT_SYMBOL_GPL(dw_hdmi_bind);
 
-void dw_hdmi_unbind(struct device *dev)
+static void __dw_hdmi_remove(struct dw_hdmi *hdmi)
 {
-	struct dw_hdmi *hdmi = dev_get_drvdata(dev);
-
 	if (hdmi->audio && !IS_ERR(hdmi->audio))
 		platform_device_unregister(hdmi->audio);
 
@@ -2077,6 +2061,70 @@ void dw_hdmi_unbind(struct device *dev)
 	else
 		i2c_put_adapter(hdmi->ddc);
 }
+
+/* -----------------------------------------------------------------------------
+ * Probe/remove API, used from platforms based on the DRM bridge API.
+ */
+int dw_hdmi_probe(struct platform_device *pdev,
+		  const struct dw_hdmi_plat_data *plat_data)
+{
+	struct dw_hdmi *hdmi;
+	int ret;
+
+	hdmi = __dw_hdmi_probe(pdev, plat_data);
+	if (IS_ERR(hdmi))
+		return PTR_ERR(hdmi);
+
+	ret = drm_bridge_add(&hdmi->bridge);
+	if (ret < 0) {
+		__dw_hdmi_remove(hdmi);
+		return ret;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(dw_hdmi_probe);
+
+void dw_hdmi_remove(struct platform_device *pdev)
+{
+	struct dw_hdmi *hdmi = platform_get_drvdata(pdev);
+
+	drm_bridge_remove(&hdmi->bridge);
+
+	__dw_hdmi_remove(hdmi);
+}
+EXPORT_SYMBOL_GPL(dw_hdmi_remove);
+
+/* -----------------------------------------------------------------------------
+ * Bind/unbind API, used from platforms based on the component framework.
+ */
+int dw_hdmi_bind(struct platform_device *pdev, struct drm_encoder *encoder,
+		 const struct dw_hdmi_plat_data *plat_data)
+{
+	struct dw_hdmi *hdmi;
+	int ret;
+
+	hdmi = __dw_hdmi_probe(pdev, plat_data);
+	if (IS_ERR(hdmi))
+		return PTR_ERR(hdmi);
+
+	ret = drm_bridge_attach(encoder, &hdmi->bridge, NULL);
+	if (ret) {
+		dw_hdmi_remove(pdev);
+		DRM_ERROR("Failed to initialize bridge with drm\n");
+		return ret;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(dw_hdmi_bind);
+
+void dw_hdmi_unbind(struct device *dev)
+{
+	struct dw_hdmi *hdmi = dev_get_drvdata(dev);
+
+	__dw_hdmi_remove(hdmi);
+}
 EXPORT_SYMBOL_GPL(dw_hdmi_unbind);
 
 MODULE_AUTHOR("Sascha Hauer <s.hauer@pengutronix.de>");

include/drm/bridge/dw_hdmi.h

@@ -56,6 +56,9 @@ struct dw_hdmi_plat_data {
 					   struct drm_display_mode *mode);
 };
 
+int dw_hdmi_probe(struct platform_device *pdev,
+		  const struct dw_hdmi_plat_data *plat_data);
+void dw_hdmi_remove(struct platform_device *pdev);
 void dw_hdmi_unbind(struct device *dev);
 int dw_hdmi_bind(struct platform_device *pdev, struct drm_encoder *encoder,
 		 const struct dw_hdmi_plat_data *plat_data);