[PATCH 2/2] media: i2c: mt9t112: Add device tree support

[Jacopo Mondi <jacopo+renesas@jmondi.org>]

Add support for OF systems to mt9t112 image sensor driver.

As the devicetree bindings use standard name for 'powerdown' gpio, and while
at there, update the existing mt9t112 users to use the new name.

Signed-off-by: Jacopo Mondi <jacopo+renesas@jmondi.org>
---
 arch/sh/boards/mach-ecovec24/setup.c |  4 +-
 drivers/media/i2c/mt9t112.c          | 87 +++++++++++++++++++++++++++++++-----
 2 files changed, 77 insertions(+), 14 deletions(-)

diff --git a/arch/sh/boards/mach-ecovec24/setup.c b/arch/sh/boards/mach-ecovec24/setup.c
index adc61d1..16de9ec 100644
--- a/arch/sh/boards/mach-ecovec24/setup.c
+++ b/arch/sh/boards/mach-ecovec24/setup.c
@@ -480,7 +480,7 @@ static struct gpiod_lookup_table tw9910_gpios = {
 static struct gpiod_lookup_table mt9t112_0_gpios = {
 	.dev_id		= "0-003c",
 	.table		= {
-		GPIO_LOOKUP("sh7724_pfc", GPIO_PTA3, "standby",
+		GPIO_LOOKUP("sh7724_pfc", GPIO_PTA3, "powerdown",
 			    GPIO_ACTIVE_HIGH),
 	},
 };
@@ -488,7 +488,7 @@ static struct gpiod_lookup_table mt9t112_0_gpios = {
 static struct gpiod_lookup_table mt9t112_1_gpios = {
 	.dev_id		= "1-003c",
 	.table		= {
-		GPIO_LOOKUP("sh7724_pfc", GPIO_PTA4, "standby",
+		GPIO_LOOKUP("sh7724_pfc", GPIO_PTA4, "powerdown",
 			    GPIO_ACTIVE_HIGH),
 	},
 };
diff --git a/drivers/media/i2c/mt9t112.c b/drivers/media/i2c/mt9t112.c
index af8cca9..704e7fb 100644
--- a/drivers/media/i2c/mt9t112.c
+++ b/drivers/media/i2c/mt9t112.c
@@ -32,6 +32,7 @@

 #include <media/i2c/mt9t112.h>
 #include <media/v4l2-common.h>
+#include <media/v4l2-fwnode.h>
 #include <media/v4l2-image-sizes.h>
 #include <media/v4l2-subdev.h>

@@ -77,6 +78,15 @@
 #define VAR(id, offset)  _VAR(id, offset, 0x0000)
 #define VAR8(id, offset) _VAR(id, offset, 0x8000)

+/*
+ * Default PLL configuration for 24MHz input clock
+ */
+static struct mt9t112_platform_data mt9t112_default_pdata_24MHz = {
+	.divider	= {
+		0x49, 0x6, 0, 6, 0, 9, 9, 6, 0,
+	},
+};
+
 /************************************************************************
  *			struct
  ***********************************************************************/
@@ -88,6 +98,7 @@ struct mt9t112_format {
 };

 struct mt9t112_priv {
+	struct device			*dev;
 	struct v4l2_subdev		 subdev;
 	struct mt9t112_platform_data	*info;
 	struct i2c_client		*client;
@@ -1066,13 +1077,39 @@ static int mt9t112_camera_probe(struct i2c_client *client)
 	return ret;
 }

+static int mt9t112_parse_dt(struct mt9t112_priv *priv)
+{
+	struct fwnode_handle *fwnode = dev_fwnode(priv->dev);
+	struct fwnode_handle *ep;
+	struct v4l2_fwnode_endpoint vep;
+	int ret;
+
+	ep = fwnode_graph_get_next_endpoint(fwnode, NULL);
+	if (IS_ERR_OR_NULL(ep)) {
+		dev_err(priv->dev, "No endpoint registered\n");
+		return PTR_ERR(ep);
+	}
+
+	ret = v4l2_fwnode_endpoint_parse(ep, &vep);
+	fwnode_handle_put(ep);
+	if (ret) {
+		dev_err(priv->dev, "Unable to parse endpoint: %d\n", ret);
+		return ret;
+	}
+
+	if (vep.bus.parallel.flags & V4L2_MBUS_PCLK_SAMPLE_RISING)
+		priv->info->flags = MT9T112_FLAG_PCLK_RISING_EDGE;
+
+	return 0;
+}
+
 static int mt9t112_probe(struct i2c_client *client,
 			 const struct i2c_device_id *did)
 {
 	struct mt9t112_priv *priv;
 	int ret;

-	if (!client->dev.platform_data) {
+	if (!client->dev.of_node && !client->dev.platform_data) {
 		dev_err(&client->dev, "mt9t112: missing platform data!\n");
 		return -EINVAL;
 	}
@@ -1081,23 +1118,39 @@ static int mt9t112_probe(struct i2c_client *client,
 	if (!priv)
 		return -ENOMEM;

-	priv->info = client->dev.platform_data;
 	priv->init_done = false;
-
-	v4l2_i2c_subdev_init(&priv->subdev, client, &mt9t112_subdev_ops);
-
-	priv->clk = devm_clk_get(&client->dev, "extclk");
-	if (PTR_ERR(priv->clk) == -ENOENT) {
+	priv->dev = &client->dev;
+
+	if (client->dev.platform_data) {
+		priv->info = client->dev.platform_data;
+
+		priv->clk = devm_clk_get(&client->dev, "extclk");
+		if (PTR_ERR(priv->clk) == -ENOENT) {
+			priv->clk = NULL;
+		} else if (IS_ERR(priv->clk)) {
+			dev_err(&client->dev,
+				"Unable to get clock \"extclk\"\n");
+			return PTR_ERR(priv->clk);
+		}
+	} else {
+		/*
+		 * External clock frequencies != 24MHz are only supported
+		 * for non-OF systems.
+		 */
 		priv->clk = NULL;
-	} else if (IS_ERR(priv->clk)) {
-		dev_err(&client->dev, "Unable to get clock \"extclk\"\n");
-		return PTR_ERR(priv->clk);
+		priv->info = &mt9t112_default_pdata_24MHz;
+
+		ret = mt9t112_parse_dt(priv);
+		if (ret)
+			return ret;
 	}

-	priv->standby_gpio = devm_gpiod_get_optional(&client->dev, "standby",
+	v4l2_i2c_subdev_init(&priv->subdev, client, &mt9t112_subdev_ops);
+
+	priv->standby_gpio = devm_gpiod_get_optional(&client->dev, "powerdown",
 						     GPIOD_OUT_HIGH);
 	if (IS_ERR(priv->standby_gpio)) {
-		dev_err(&client->dev, "Unable to get gpio \"standby\"\n");
+		dev_err(&client->dev, "Unable to get gpio \"powerdown\"\n");
 		return PTR_ERR(priv->standby_gpio);
 	}

@@ -1124,9 +1177,19 @@ static const struct i2c_device_id mt9t112_id[] = {
 };
 MODULE_DEVICE_TABLE(i2c, mt9t112_id);

+#if IS_ENABLED(CONFIG_OF)
+static const struct of_device_id mt9t112_of_match[] = {
+	{ .compatible = "micron,mt9t111", },
+	{ .compatible = "micron,mt9t112", },
+	{ /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, mt9t112_of_match);
+#endif
+
 static struct i2c_driver mt9t112_i2c_driver = {
 	.driver = {
 		.name = "mt9t112",
+		.of_match_table = of_match_ptr(mt9t112_of_match),
 	},
 	.probe    = mt9t112_probe,
 	.remove   = mt9t112_remove,
--
2.7.4