Input: twl4030-keypad - add device tree support

* TWL4030's Keypad Controller device tree bindings

TWL4030's Keypad controller is used to interface a SoC with a matrix-type

keypad device. The keypad controller supports multiple row and column lines.

A key can be placed at each intersection of a unique row and a unique column.

The keypad controller can sense a key-press and key-release and report the

event using a interrupt to the cpu.

This binding is based on the matrix-keymap binding with the following

changes:

 * keypad,num-rows and keypad,num-columns are required.

Required SoC Specific Properties:

- compatible: should be one of the following

   - "ti,twl4030-keypad": For controllers compatible with twl4030 keypad

      controller.

- interrupt: should be one of the following

   - <1>: For controllers compatible with twl4030 keypad controller.

Example:

	twl_keypad: keypad {

		compatible = "ti,twl4030-keypad";

		interrupts = <1>;

		keypad,num-rows = <8>;

		keypad,num-columns = <8>;

	};

#include <linux/platform_device.h>

#include <linux/i2c/twl.h>

#include <linux/slab.h>

#include <linux/of.h>

/*

 * The TWL4030 family chips include a keypad controller that supports

struct twl4030_keypad {

	unsigned short	keymap[TWL4030_KEYMAP_SIZE];

	u16		kp_state[TWL4030_MAX_ROWS];

	bool		autorepeat;

	unsigned	n_rows;

	unsigned	n_cols;

	unsigned	irq;

static int twl4030_kp_probe(struct platform_device *pdev)

{

	struct twl4030_keypad_data *pdata = dev_get_platdata(&pdev->dev);

	const struct matrix_keymap_data *keymap_data;

	const struct matrix_keymap_data *keymap_data = NULL;

	struct twl4030_keypad *kp;

	struct input_dev *input;

	u8 reg;

	int error;

	if (!pdata || !pdata->rows || !pdata->cols || !pdata->keymap_data ||

	    pdata->rows > TWL4030_MAX_ROWS || pdata->cols > TWL4030_MAX_COLS) {

		dev_err(&pdev->dev, "Invalid platform_data\n");

		return -EINVAL;

	}

	keymap_data = pdata->keymap_data;

	kp = kzalloc(sizeof(*kp), GFP_KERNEL);

	input = input_allocate_device();

	if (!kp || !input) {

		goto err1;

	}

	/* Get the debug Device */

	/* get the debug device */

	kp->dbg_dev		= &pdev->dev;

	kp->input		= input;

	kp->n_rows = pdata->rows;

	kp->n_cols = pdata->cols;

	kp->irq = platform_get_irq(pdev, 0);

	/* setup input device */

	input->name		= "TWL4030 Keypad";

	input->phys		= "twl4030_keypad/input0";

	input->id.product	= 0x0001;

	input->id.version	= 0x0003;

	if (pdata) {

		if (!pdata->rows || !pdata->cols || !pdata->keymap_data) {

			dev_err(&pdev->dev, "Missing platform_data\n");

			error = -EINVAL;

			goto err1;

		}

		kp->n_rows = pdata->rows;

		kp->n_cols = pdata->cols;

		kp->autorepeat = pdata->rep;

		keymap_data = pdata->keymap_data;

	} else {

		error = matrix_keypad_parse_of_params(&pdev->dev, &kp->n_rows,

						      &kp->n_cols);

		if (error)

			goto err1;

		kp->autorepeat = true;

	}

	if (kp->n_rows > TWL4030_MAX_ROWS || kp->n_cols > TWL4030_MAX_COLS) {

		dev_err(&pdev->dev,

			"Invalid rows/cols amount specified in platform/devicetree data\n");

		error = -EINVAL;

		goto err1;

	}

	kp->irq = platform_get_irq(pdev, 0);

	if (!kp->irq) {

		dev_err(&pdev->dev, "no keyboard irq assigned\n");

		error = -EINVAL;

		goto err1;

	}

	error = matrix_keypad_build_keymap(keymap_data, NULL,

					   TWL4030_MAX_ROWS,

					   1 << TWL4030_ROW_SHIFT,

	input_set_capability(input, EV_MSC, MSC_SCAN);

	/* Enable auto repeat feature of Linux input subsystem */

	if (pdata->rep)

	if (kp->autorepeat)

		__set_bit(EV_REP, input->evbit);

	error = input_register_device(input);

	return 0;

}

#ifdef CONFIG_OF

static const struct of_device_id twl4030_keypad_dt_match_table[] = {

	{ .compatible = "ti,twl4030-keypad" },

	{},

};

MODULE_DEVICE_TABLE(of, twl4030_keypad_dt_match_table);

#endif

/*

 * NOTE: twl4030 are multi-function devices connected via I2C.

 * So this device is a child of an I2C parent, thus it needs to

	.driver		= {

		.name	= "twl4030_keypad",

		.owner	= THIS_MODULE,

		.of_match_table = of_match_ptr(twl4030_keypad_dt_match_table),

	},

};

module_platform_driver(twl4030_kp_driver);