mfd: Add device tree support for max77686

Maxim MAX77686 multi-function device

MAX77686 is a Mulitifunction device with PMIC, RTC and Charger on chip. It is

interfaced to host controller using i2c interface. PMIC and Charger submodules

are addressed using same i2c slave address whereas RTC submodule uses

different i2c slave address,presently for which we are statically creating i2c

client while probing.This document describes the binding for mfd device and

PMIC submodule.

Required properties:

- compatible : Must be "maxim,max77686";

- reg : Specifies the i2c slave address of PMIC block.

- interrupts : This i2c device has an IRQ line connected to the main SoC.

- interrupt-parent : The parent interrupt controller.

Optional node:

- voltage-regulators : The regulators of max77686 have to be instantiated

  under subnode named "voltage-regulators" using the following format.

	regulator_name {

		regulator-compatible = LDOn/BUCKn

		standard regulator constraints....

	};

	refer Documentation/devicetree/bindings/regulator/regulator.txt

  The regulator-compatible property of regulator should initialized with string

to get matched with their hardware counterparts as follow:

	-LDOn 	:	for LDOs, where n can lie in range 1 to 26.

		 	example: LDO1, LDO2, LDO26.

	-BUCKn 	:	for BUCKs, where n can lie in range 1 to 9.

			example: BUCK1, BUCK5, BUCK9.

Example:

	max77686@09 {

		compatible = "maxim,max77686";

		interrupt-parent = <&wakeup_eint>;

		interrupts = <26 0>;

		reg = <0x09>;

		voltage-regulators {

			ldo11_reg {

				regulator-compatible = "LDO11";

				regulator-name = "vdd_ldo11";

				regulator-min-microvolt = <1900000>;

				regulator-max-microvolt = <1900000>;

				regulator-always-on;

			};

			buck1_reg {

				regulator-compatible = "BUCK1";

				regulator-name = "vdd_mif";

				regulator-min-microvolt = <950000>;

				regulator-max-microvolt = <1300000>;

				regulator-always-on;

				regulator-boot-on;

			};

	}

#define I2C_ADDR_RTC	(0x0C >> 1)

static struct of_device_id __devinitdata max77686_pmic_dt_match[] = {

	{.compatible = "maxim,max77686",        .data = 0},

	{},

};

static struct mfd_cell max77686_devs[] = {

	{ .name = "max77686-pmic", },

	{ .name = "max77686-rtc", },

	.val_bits = 8,

};

#ifdef CONFIG_OF

static struct max77686_platform_data *max77686_i2c_parse_dt_pdata(struct device

								  *dev)

{

	struct max77686_platform_data *pd;

	pd = devm_kzalloc(dev, sizeof(*pd), GFP_KERNEL);

	if (!pd) {

		dev_err(dev, "could not allocate memory for pdata\n");

		return NULL;

	}

	dev->platform_data = pd;

	return pd;

}

#else

static struct max77686_platform_data *max77686_i2c_parse_dt_pdata(struct device

								  *dev)

{

	return 0;

}

#endif

static int max77686_i2c_probe(struct i2c_client *i2c,

			      const struct i2c_device_id *id)

{

	struct max77686_dev *max77686;

	struct max77686_dev *max77686 = NULL;

	struct max77686_platform_data *pdata = i2c->dev.platform_data;

	unsigned int data;

	int ret = 0;

	if (i2c->dev.of_node)

		pdata = max77686_i2c_parse_dt_pdata(&i2c->dev);

	if (!pdata) {

		ret = -EIO;

		dev_err(&i2c->dev, "No platform data found.\n");

		goto err;

	}

	max77686 = kzalloc(sizeof(struct max77686_dev), GFP_KERNEL);

	if (max77686 == NULL)

		return -ENOMEM;

	max77686->i2c = i2c;

	max77686->type = id->driver_data;

	if (!pdata) {

		ret = -EIO;

		goto err;

	}

	max77686->wakeup = pdata->wakeup;

	max77686->irq_gpio = pdata->irq_gpio;

	max77686->irq = i2c->irq;

	.driver = {

		   .name = "max77686",

		   .owner = THIS_MODULE,

		   .of_match_table = of_match_ptr(max77686_pmic_dt_match),

	},

	.probe = max77686_i2c_probe,

	.remove = max77686_i2c_remove,