drm/armada: convert to componentized support

Convert the Armada DRM driver to use the component helpers, which will
permit us to clean up the driver and move towards an implementation
which is compatible with a DT description of the hardware.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

drivers/gpu/drm/armada/armada_drv.c

@@ -6,7 +6,9 @@
  * published by the Free Software Foundation.
  */
 #include <linux/clk.h>
+#include <linux/component.h>
 #include <linux/module.h>
+#include <linux/of_graph.h>
 #include <drm/drmP.h>
 #include <drm/drm_crtc_helper.h>
 #include "armada_crtc.h"
@@ -52,6 +54,11 @@ static const struct armada_drm_slave_config tda19988_config = {
 };
 #endif
 
+static bool is_componentized(struct device *dev)
+{
+	return dev->of_node || dev->platform_data;
+}
+
 static void armada_drm_unref_work(struct work_struct *work)
 {
 	struct armada_private *priv =
@@ -166,26 +173,35 @@ static int armada_drm_load(struct drm_device *dev, unsigned long flags)
 			goto err_kms;
 	}
 
+	if (is_componentized(dev->dev)) {
+		ret = component_bind_all(dev->dev, dev);
+		if (ret)
+			goto err_kms;
+	} else {
 #ifdef CONFIG_DRM_ARMADA_TDA1998X
-	ret = armada_drm_connector_slave_create(dev, &tda19988_config);
-	if (ret)
-		goto err_kms;
+		ret = armada_drm_connector_slave_create(dev, &tda19988_config);
+		if (ret)
+			goto err_kms;
 #endif
+	}
 
 	ret = drm_vblank_init(dev, dev->mode_config.num_crtc);
 	if (ret)
-		goto err_kms;
+		goto err_comp;
 
 	dev->vblank_disable_allowed = 1;
 
 	ret = armada_fbdev_init(dev);
 	if (ret)
-		goto err_kms;
+		goto err_comp;
 
 	drm_kms_helper_poll_init(dev);
 
 	return 0;
 
+ err_comp:
+	if (is_componentized(dev->dev))
+		component_unbind_all(dev->dev, dev);
  err_kms:
 	drm_mode_config_cleanup(dev);
 	drm_mm_takedown(&priv->linear);
@@ -200,6 +216,10 @@ static int armada_drm_unload(struct drm_device *dev)
 
 	drm_kms_helper_poll_fini(dev);
 	armada_fbdev_fini(dev);
+
+	if (is_componentized(dev->dev))
+		component_unbind_all(dev->dev, dev);
+
 	drm_mode_config_cleanup(dev);
 	drm_mm_takedown(&priv->linear);
 	flush_work(&priv->fb_unref_work);
@@ -314,14 +334,135 @@ static struct drm_driver armada_drm_driver = {
 	.fops			= &armada_drm_fops,
 };
 
+static int armada_drm_bind(struct device *dev)
+{
+	return drm_platform_init(&armada_drm_driver, to_platform_device(dev));
+}
+
+static void armada_drm_unbind(struct device *dev)
+{
+	drm_put_dev(dev_get_drvdata(dev));
+}
+
+static int compare_of(struct device *dev, void *data)
+{
+	return dev->of_node == data;
+}
+
+static int compare_dev_name(struct device *dev, void *data)
+{
+	const char *name = data;
+	return !strcmp(dev_name(dev), name);
+}
+
+static void armada_add_endpoints(struct device *dev,
+	struct component_match **match, struct device_node *port)
+{
+	struct device_node *ep, *remote;
+
+	for_each_child_of_node(port, ep) {
+		remote = of_graph_get_remote_port_parent(ep);
+		if (!remote || !of_device_is_available(remote)) {
+			of_node_put(remote);
+			continue;
+		} else if (!of_device_is_available(remote->parent)) {
+			dev_warn(dev, "parent device of %s is not available\n",
+				 remote->full_name);
+			of_node_put(remote);
+			continue;
+		}
+
+		component_match_add(dev, match, compare_of, remote);
+		of_node_put(remote);
+	}
+}
+
+static int armada_drm_find_components(struct device *dev,
+	struct component_match **match)
+{
+	struct device_node *port;
+	int i;
+
+	if (dev->of_node) {
+		struct device_node *np = dev->of_node;
+
+		for (i = 0; ; i++) {
+			port = of_parse_phandle(np, "ports", i);
+			if (!port)
+				break;
+
+			component_match_add(dev, match, compare_of, port);
+			of_node_put(port);
+		}
+
+		if (i == 0) {
+			dev_err(dev, "missing 'ports' property\n");
+			return -ENODEV;
+		}
+
+		for (i = 0; ; i++) {
+			port = of_parse_phandle(np, "ports", i);
+			if (!port)
+				break;
+
+			armada_add_endpoints(dev, match, port);
+			of_node_put(port);
+		}
+	} else if (dev->platform_data) {
+		char **devices = dev->platform_data;
+		struct device *d;
+
+		for (i = 0; devices[i]; i++)
+			component_match_add(dev, match, compare_dev_name,
+					    devices[i]);
+
+		if (i == 0) {
+			dev_err(dev, "missing 'ports' property\n");
+			return -ENODEV;
+		}
+
+		for (i = 0; devices[i]; i++) {
+			d = bus_find_device_by_name(&platform_bus_type, NULL,
+					devices[i]);
+			if (d && d->of_node) {
+				for_each_child_of_node(d->of_node, port)
+					armada_add_endpoints(dev, match, port);
+			}
+			put_device(d);
+		}
+	}
+
+	return 0;
+}
+
+static const struct component_master_ops armada_master_ops = {
+	.bind = armada_drm_bind,
+	.unbind = armada_drm_unbind,
+};
+
 static int armada_drm_probe(struct platform_device *pdev)
 {
-	return drm_platform_init(&armada_drm_driver, pdev);
+	if (is_componentized(&pdev->dev)) {
+		struct component_match *match = NULL;
+		int ret;
+
+		ret = armada_drm_find_components(&pdev->dev, &match);
+		if (ret < 0)
+			return ret;
+
+		return component_master_add_with_match(&pdev->dev,
+				&armada_master_ops, match);
+	} else {
+		return drm_platform_init(&armada_drm_driver, pdev);
+	}
 }
 
 static int armada_drm_remove(struct platform_device *pdev)
 {
-	drm_put_dev(platform_get_drvdata(pdev));
+	if (is_componentized(&pdev->dev))
+		component_master_del(&pdev->dev, &armada_master_ops);
+	else
+		drm_put_dev(platform_get_drvdata(pdev));
 	return 0;
 }