[PATCH v4 04/10] s5p-fimc: Add device tree support for the main media device driver

[Sylwester Nawrocki <s.nawrocki@samsung.com>]

This patch adds changes required for the main camera media device
driver to be initialized on systems instantiated from the device tree.

The platform devices corresponding to child nodes of the 'camera'
node are looked up and and registered as sub-devices to the common
media device. The main driver's probing is deferred if any of the
sub-device drivers is not yet initialized and ready.

An OF matching table is added for the main driver associated with
the 'camera' node.

Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
---
 drivers/media/platform/s5p-fimc/fimc-core.c    |    1 -
 drivers/media/platform/s5p-fimc/fimc-mdevice.c |   77 +++++++++++++++++++++---
 drivers/media/platform/s5p-fimc/fimc-mdevice.h |    4 ++
 include/media/s5p_fimc.h                       |    1 +
 4 files changed, 75 insertions(+), 8 deletions(-)

diff --git a/drivers/media/platform/s5p-fimc/fimc-core.c b/drivers/media/platform/s5p-fimc/fimc-core.c
index 07ca0e0..ba743a5 100644
--- a/drivers/media/platform/s5p-fimc/fimc-core.c
+++ b/drivers/media/platform/s5p-fimc/fimc-core.c
@@ -1276,7 +1276,6 @@ static const struct platform_device_id fimc_driver_ids[] = {
 	},
 	{ },
 };
-MODULE_DEVICE_TABLE(platform, fimc_driver_ids);
 
 static const struct of_device_id fimc_of_match[] = {
 	{
diff --git a/drivers/media/platform/s5p-fimc/fimc-mdevice.c b/drivers/media/platform/s5p-fimc/fimc-mdevice.c
index f49f6f1..c113734 100644
--- a/drivers/media/platform/s5p-fimc/fimc-mdevice.c
+++ b/drivers/media/platform/s5p-fimc/fimc-mdevice.c
@@ -17,6 +17,8 @@
 #include <linux/kernel.h>
 #include <linux/list.h>
 #include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
 #include <linux/platform_device.h>
 #include <linux/pm_runtime.h>
 #include <linux/types.h>
@@ -457,6 +459,51 @@ static int fimc_md_pdev_match(struct device *dev, void *data)
 	return 0;
 }
 
+/* Register FIMC, FIMC-LITE and CSIS media entities */
+#ifdef CONFIG_OF
+static int fimc_md_register_of_platform_entities(struct fimc_md *fmd,
+						 struct device_node *parent)
+{
+	struct device_node *node;
+	int ret = 0;
+
+	for_each_available_child_of_node(parent, node) {
+		struct platform_device *pdev;
+		int plat_entity = -1;
+
+		pdev = of_find_device_by_node(node);
+		if (!pdev)
+			continue;
+
+		/* If driver of any entity isn't ready try all again later. */
+		if (!strcmp(node->name, CSIS_OF_NODE_NAME))
+			plat_entity = IDX_CSIS;
+		else if (!strcmp(node->name, FIMC_LITE_OF_NODE_NAME))
+			plat_entity = IDX_FLITE;
+		else if	(!strcmp(node->name, FIMC_OF_NODE_NAME))
+			plat_entity = IDX_FIMC;
+
+		if (plat_entity >= 0)
+			ret = fimc_md_register_platform_entity(fmd, pdev,
+							plat_entity);
+		put_device(&pdev->dev);
+		if (ret < 0)
+			break;
+
+		/* FIMC-IS child devices */
+		if (plat_entity == IDX_IS_ISP) {
+			ret = fimc_md_register_of_platform_entities(fmd, node);
+			if (ret < 0)
+				break;
+		}
+	}
+
+	return ret;
+}
+#else
+#define fimc_md_register_platform_entities(fmd) (-ENOSYS)
+#endif
+
 static void fimc_md_unregister_entities(struct fimc_md *fmd)
 {
 	int i;
@@ -948,8 +995,8 @@ static int fimc_md_probe(struct platform_device *pdev)
 	v4l2_dev = &fmd->v4l2_dev;
 	v4l2_dev->mdev = &fmd->media_dev;
 	v4l2_dev->notify = fimc_sensor_notify;
-	snprintf(v4l2_dev->name, sizeof(v4l2_dev->name), "%s",
-		 dev_name(&pdev->dev));
+	strlcpy(v4l2_dev->name, "s5p-fimc-md", sizeof(v4l2_dev->name));
+
 
 	ret = v4l2_device_register(&pdev->dev, &fmd->v4l2_dev);
 	if (ret < 0) {
@@ -965,13 +1012,16 @@ static int fimc_md_probe(struct platform_device *pdev)
 	if (ret)
 		goto err_clk;
 
-	fmd->user_subdev_api = false;
+	fmd->user_subdev_api = (dev->of_node != NULL);
 
 	/* Protect the media graph while we're registering entities */
 	mutex_lock(&fmd->media_dev.graph_mutex);
 
-	ret = bus_for_each_dev(&platform_bus_type, NULL, fmd,
-					fimc_md_pdev_match);
+	if (fmd->pdev->dev.of_node)
+		ret = fimc_md_register_of_platform_entities(fmd, dev->of_node);
+	else
+		ret = bus_for_each_dev(&platform_bus_type, NULL, fmd,
+						fimc_md_pdev_match);
 	if (ret)
 		goto err_unlock;
 
@@ -1019,12 +1069,25 @@ static int fimc_md_remove(struct platform_device *pdev)
 	return 0;
 }
 
+static struct platform_device_id fimc_driver_ids[] __always_unused = {
+	{ .name = "s5p-fimc-md" },
+	{ },
+};
+MODULE_DEVICE_TABLE(platform, fimc_driver_ids);
+
+static const struct of_device_id fimc_md_of_match[] __initconst = {
+	{ .compatible = "samsung,fimc" },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, fimc_md_of_match);
+
 static struct platform_driver fimc_md_driver = {
 	.probe		= fimc_md_probe,
 	.remove		= fimc_md_remove,
 	.driver = {
-		.name	= "s5p-fimc-md",
-		.owner	= THIS_MODULE,
+		.of_match_table = fimc_md_of_match,
+		.name		= "s5p-fimc-md",
+		.owner		= THIS_MODULE,
 	}
 };
 
diff --git a/drivers/media/platform/s5p-fimc/fimc-mdevice.h b/drivers/media/platform/s5p-fimc/fimc-mdevice.h
index 06b0d82..f3e0251 100644
--- a/drivers/media/platform/s5p-fimc/fimc-mdevice.h
+++ b/drivers/media/platform/s5p-fimc/fimc-mdevice.h
@@ -21,6 +21,10 @@
 #include "fimc-lite.h"
 #include "mipi-csis.h"
 
+#define FIMC_OF_NODE_NAME	"fimc"
+#define FIMC_LITE_OF_NODE_NAME	"fimc-lite"
+#define CSIS_OF_NODE_NAME	"csis"
+
 /* Group IDs of sensor, MIPI-CSIS, FIMC-LITE and the writeback subdevs. */
 #define GRP_ID_SENSOR		(1 << 8)
 #define GRP_ID_FIMC_IS_SENSOR	(1 << 9)
diff --git a/include/media/s5p_fimc.h b/include/media/s5p_fimc.h
index 28f3590..17fd2fa 100644
--- a/include/media/s5p_fimc.h
+++ b/include/media/s5p_fimc.h
@@ -81,6 +81,7 @@ enum fimc_subdev_index {
 	IDX_SENSOR,
 	IDX_CSIS,
 	IDX_FLITE,
+	IDX_IS_ISP,
 	IDX_FIMC,
 	IDX_MAX,
 };
-- 
1.7.9.5