[media] Add device tree support to adp1653 flash driver

Nokia N900 is switching to device tree, make sure we can use flash
there, too.

Signed-off-by: Pavel Machek <[e-mail]>
Signed-off-by: Mauro Carvalho Chehab <[e-mail]>

Documentation/devicetree/bindings/media/i2c/adp1653.txt

···
+* Analog Devices ADP1653 flash LED driver
+
+Required Properties:
+
+  - compatible: Must contain be "adi,adp1653"
+
+  - reg: I2C slave address
+
+  - gpios: References to the GPIO that controls the power for the chip.
+
+There are two led outputs available - flash and indicator. One led is
+represented by one child node, nodes need to be named "flash" and "indicator".
+
+Required properties of the LED child node:
+- max-microamp : see Documentation/devicetree/bindings/leds/common.txt
+
+Required properties of the flash LED child node:
+
+- flash-max-microamp : see Documentation/devicetree/bindings/leds/common.txt
+- flash-timeout-us : see Documentation/devicetree/bindings/leds/common.txt
+
+Example:
+
+	adp1653: led-controller@30 {
+		compatible = "adi,adp1653";
+		reg = <0x30>;
+		gpios = <&gpio3 24 GPIO_ACTIVE_HIGH>; /* 88 */
+
+		flash {
+			flash-timeout-us = <500000>;
+			flash-max-microamp = <320000>;
+			max-microamp = <50000>;
+		};
+		indicator {
+			max-microamp = <17500>;
+		};
+	};

drivers/media/i2c/adp1653.c

···
  * Contributors:
  *	Sakari Ailus <[e-mail]>
  *	Tuukka Toivonen <[e-mail]>
+ *	Pavel Machek <[e-mail]>
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License
···
 #include <linux/module.h>
 #include <linux/i2c.h>
 #include <linux/slab.h>
+#include <linux/of_gpio.h>
+#include <linux/gpio.h>
 #include <media/adp1653.h>
 #include <media/v4l2-device.h>
 
···
 static int
 __adp1653_set_power(struct adp1653_flash *flash, int on)
 {
-	int ret;
+	int ret = 0;
 
-	ret = flash->platform_data->power(&flash->subdev, on);
+	if (flash->platform_data->power) {
+		ret = flash->platform_data->power(&flash->subdev, on);
+	} else {
+		gpio_set_value(flash->platform_data->power_gpio, on);
+		if (on)
+			/* Some delay is apparently required. */
+			udelay(20);
+	}
+
 	if (ret < 0)
 		return ret;
 
···
 		return 0;
 
 	ret = adp1653_init_device(flash);
-	if (ret < 0)
+	if (ret >= 0)
+		return ret;
+
+	if (flash->platform_data->power)
 		flash->platform_data->power(&flash->subdev, 0);
+	else
+		gpio_set_value(flash->platform_data->power_gpio, 0);
 
 	return ret;
 }
···
 
 #endif /* CONFIG_PM */
 
+static int adp1653_of_init(struct i2c_client *client,
+			   struct adp1653_flash *flash,
+			   struct device_node *node)
+{
+	u32 val;
+	struct adp1653_platform_data *pd;
+	enum of_gpio_flags flags;
+	int gpio;
+	struct device_node *child;
+
+	if (!node)
+		return -EINVAL;
+
+	pd = devm_kzalloc(&client->dev, sizeof(*pd), GFP_KERNEL);
+	if (!pd)
+		return -ENOMEM;
+	flash->platform_data = pd;
+
+	child = of_get_child_by_name(node, "flash");
+	if (!child)
+		return -EINVAL;
+	if (of_property_read_u32(child, "flash-timeout-microsec", &val))
+		return -EINVAL;
+
+	pd->max_flash_timeout = val;
+	if (of_property_read_u32(child, "flash-max-microamp", &val))
+		return -EINVAL;
+	pd->max_flash_intensity = val/1000;
+
+	if (of_property_read_u32(child, "max-microamp", &val))
+		return -EINVAL;
+	pd->max_torch_intensity = val/1000;
+
+	child = of_get_child_by_name(node, "indicator");
+	if (!child)
+		return -EINVAL;
+	if (of_property_read_u32(child, "max-microamp", &val))
+		return -EINVAL;
+	pd->max_indicator_intensity = val;
+
+	if (!of_find_property(node, "gpios", NULL)) {
+		dev_err(&client->dev, "No gpio node\n");
+		return -EINVAL;
+	}
+
+	pd->power_gpio = of_get_gpio_flags(node, 0, &flags);
+	if (pd->power_gpio < 0) {
+		dev_err(&client->dev, "Error getting GPIO\n");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+
 static int adp1653_probe(struct i2c_client *client,
 			 const struct i2c_device_id *devid)
 {
 	struct adp1653_flash *flash;
 	int ret;
 
-	/* we couldn't work without platform data */
-	if (client->dev.platform_data == NULL)
-		return -ENODEV;
-
 	flash = devm_kzalloc(&client->dev, sizeof(*flash), GFP_KERNEL);
 	if (flash == NULL)
 		return -ENOMEM;
 
 	flash->platform_data = client->dev.platform_data;
+	if (!flash->platform_data) {
+		ret = adp1653_of_init(client, flash, client->dev.of_node);
+		if (ret)
+			return ret;
+	}
 
 	mutex_init(&flash->power_lock);
 
···
 		goto free_and_quit;
 
 	flash->subdev.entity.type = MEDIA_ENT_T_V4L2_SUBDEV_FLASH;
-
 	return 0;
 
 free_and_quit:
+	dev_err(&client->dev, "adp1653: failed to register device\n");
 	v4l2_ctrl_handler_free(&flash->ctrls);
 	return ret;
 }
···
 };
 MODULE_DEVICE_TABLE(i2c, adp1653_id_table);
 
-static struct dev_pm_ops adp1653_pm_ops = {
+static const struct dev_pm_ops adp1653_pm_ops = {
 	.suspend	= adp1653_suspend,
 	.resume		= adp1653_resume,
 };