[linux.git] / drivers / gpio / gpio-max732x.c

/*
 *  MAX732x I2C Port Expander with 8/16 I/O
 *
 *  Copyright (C) 2007 Marvell International Ltd.
 *  Copyright (C) 2008 Jack Ren <[email protected]>
 *  Copyright (C) 2008 Eric Miao <[email protected]>
 *
 *  Derived from drivers/gpio/pca953x.c
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; version 2 of the License.
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/gpio.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/i2c.h>
#include <linux/i2c/max732x.h>


/*
 * Each port of MAX732x (including MAX7319) falls into one of the
 * following three types:
 *
 *   - Push Pull Output
 *   - Input
 *   - Open Drain I/O
 *
 * designated by 'O', 'I' and 'P' individually according to MAXIM's
 * datasheets. 'I' and 'P' ports are interrupt capables, some with
 * a dedicated interrupt mask.
 *
 * There are two groups of I/O ports, each group usually includes
 * up to 8 I/O ports, and is accessed by a specific I2C address:
 *
 *   - Group A : by I2C address 0b'110xxxx
 *   - Group B : by I2C address 0b'101xxxx
 *
 * where 'xxxx' is decided by the connections of pin AD2/AD0.  The
 * address used also affects the initial state of output signals.
 *
 * Within each group of ports, there are five known combinations of
 * I/O ports: 4I4O, 4P4O, 8I, 8P, 8O, see the definitions below for
 * the detailed organization of these ports. Only Goup A is interrupt
 * capable.
 *
 * GPIO numbers start from 'gpio_base + 0' to 'gpio_base + 8/16',
 * and GPIOs from GROUP_A are numbered before those from GROUP_B
 * (if there are two groups).
 *
 * NOTE: MAX7328/MAX7329 are drop-in replacements for PCF8574/a, so
 * they are not supported by this driver.
 */

#define PORT_NONE	0x0	/* '/' No Port */
#define PORT_OUTPUT	0x1	/* 'O' Push-Pull, Output Only */
#define PORT_INPUT	0x2	/* 'I' Input Only */
#define PORT_OPENDRAIN	0x3	/* 'P' Open-Drain, I/O */

#define IO_4I4O		0x5AA5	/* O7 O6 I5 I4 I3 I2 O1 O0 */
#define IO_4P4O		0x5FF5	/* O7 O6 P5 P4 P3 P2 O1 O0 */
#define IO_8I		0xAAAA	/* I7 I6 I5 I4 I3 I2 I1 I0 */
#define IO_8P		0xFFFF	/* P7 P6 P5 P4 P3 P2 P1 P0 */
#define IO_8O		0x5555	/* O7 O6 O5 O4 O3 O2 O1 O0 */

#define GROUP_A(x)	((x) & 0xffff)	/* I2C Addr: 0b'110xxxx */
#define GROUP_B(x)	((x) << 16)	/* I2C Addr: 0b'101xxxx */

#define INT_NONE	0x0	/* No interrupt capability */
#define INT_NO_MASK	0x1	/* Has interrupts, no mask */
#define INT_INDEP_MASK	0x2	/* Has interrupts, independent mask */
#define INT_MERGED_MASK 0x3	/* Has interrupts, merged mask */

#define INT_CAPS(x)	(((uint64_t)(x)) << 32)

enum {
	MAX7319,
	MAX7320,
	MAX7321,
	MAX7322,
	MAX7323,
	MAX7324,
	MAX7325,
	MAX7326,
	MAX7327,
};

static uint64_t max732x_features[] = {
	[MAX7319] = GROUP_A(IO_8I) | INT_CAPS(INT_MERGED_MASK),
	[MAX7320] = GROUP_B(IO_8O),
	[MAX7321] = GROUP_A(IO_8P) | INT_CAPS(INT_NO_MASK),
	[MAX7322] = GROUP_A(IO_4I4O) | INT_CAPS(INT_MERGED_MASK),
	[MAX7323] = GROUP_A(IO_4P4O) | INT_CAPS(INT_INDEP_MASK),
	[MAX7324] = GROUP_A(IO_8I) | GROUP_B(IO_8O) | INT_CAPS(INT_MERGED_MASK),
	[MAX7325] = GROUP_A(IO_8P) | GROUP_B(IO_8O) | INT_CAPS(INT_NO_MASK),
	[MAX7326] = GROUP_A(IO_4I4O) | GROUP_B(IO_8O) | INT_CAPS(INT_MERGED_MASK),
	[MAX7327] = GROUP_A(IO_4P4O) | GROUP_B(IO_8O) | INT_CAPS(INT_NO_MASK),
};

static const struct i2c_device_id max732x_id[] = {
	{ "max7319", MAX7319 },
	{ "max7320", MAX7320 },
	{ "max7321", MAX7321 },
	{ "max7322", MAX7322 },
	{ "max7323", MAX7323 },
	{ "max7324", MAX7324 },
	{ "max7325", MAX7325 },
	{ "max7326", MAX7326 },
	{ "max7327", MAX7327 },
	{ },
};
MODULE_DEVICE_TABLE(i2c, max732x_id);

struct max732x_chip {
	struct gpio_chip gpio_chip;

	struct i2c_client *client;	/* "main" client */
	struct i2c_client *client_dummy;
	struct i2c_client *client_group_a;
	struct i2c_client *client_group_b;

	unsigned int	mask_group_a;
	unsigned int	dir_input;
	unsigned int	dir_output;

	struct mutex	lock;
	uint8_t		reg_out[2];

#ifdef CONFIG_GPIO_MAX732X_IRQ
	struct mutex	irq_lock;
	int		irq_base;
	uint8_t		irq_mask;
	uint8_t		irq_mask_cur;
	uint8_t		irq_trig_raise;
	uint8_t		irq_trig_fall;
	uint8_t		irq_features;
#endif
};

static int max732x_writeb(struct max732x_chip *chip, int group_a, uint8_t val)
{
	struct i2c_client *client;
	int ret;

	client = group_a ? chip->client_group_a : chip->client_group_b;
	ret = i2c_smbus_write_byte(client, val);
	if (ret < 0) {
		dev_err(&client->dev, "failed writing\n");
		return ret;
	}

	return 0;
}

static int max732x_readb(struct max732x_chip *chip, int group_a, uint8_t *val)
{
	struct i2c_client *client;
	int ret;

	client = group_a ? chip->client_group_a : chip->client_group_b;
	ret = i2c_smbus_read_byte(client);
	if (ret < 0) {
		dev_err(&client->dev, "failed reading\n");
		return ret;
	}

	*val = (uint8_t)ret;
	return 0;
}

static inline int is_group_a(struct max732x_chip *chip, unsigned off)
{
	return (1u << off) & chip->mask_group_a;
}

static int max732x_gpio_get_value(struct gpio_chip *gc, unsigned off)
{
	struct max732x_chip *chip;
	uint8_t reg_val;
	int ret;

	chip = container_of(gc, struct max732x_chip, gpio_chip);

	ret = max732x_readb(chip, is_group_a(chip, off), &reg_val);
	if (ret < 0)
		return 0;

	return reg_val & (1u << (off & 0x7));
}

static void max732x_gpio_set_value(struct gpio_chip *gc, unsigned off, int val)
{
	struct max732x_chip *chip;
	uint8_t reg_out, mask = 1u << (off & 0x7);
	int ret;

	chip = container_of(gc, struct max732x_chip, gpio_chip);

	mutex_lock(&chip->lock);

	reg_out = (off > 7) ? chip->reg_out[1] : chip->reg_out[0];
	reg_out = (val) ? reg_out | mask : reg_out & ~mask;

	ret = max732x_writeb(chip, is_group_a(chip, off), reg_out);
	if (ret < 0)
		goto out;

	/* update the shadow register then */
	if (off > 7)
		chip->reg_out[1] = reg_out;
	else
		chip->reg_out[0] = reg_out;
out:
	mutex_unlock(&chip->lock);
}

static int max732x_gpio_direction_input(struct gpio_chip *gc, unsigned off)
{
	struct max732x_chip *chip;
	unsigned int mask = 1u << off;

	chip = container_of(gc, struct max732x_chip, gpio_chip);

	if ((mask & chip->dir_input) == 0) {
		dev_dbg(&chip->client->dev, "%s port %d is output only\n",
			chip->client->name, off);
		return -EACCES;
	}

	/*
	 * Open-drain pins must be set to high impedance (which is
	 * equivalent to output-high) to be turned into an input.
	 */
	if ((mask & chip->dir_output))
		max732x_gpio_set_value(gc, off, 1);

	return 0;
}

static int max732x_gpio_direction_output(struct gpio_chip *gc,
		unsigned off, int val)
{
	struct max732x_chip *chip;
	unsigned int mask = 1u << off;

	chip = container_of(gc, struct max732x_chip, gpio_chip);

	if ((mask & chip->dir_output) == 0) {
		dev_dbg(&chip->client->dev, "%s port %d is input only\n",
			chip->client->name, off);
		return -EACCES;
	}

	max732x_gpio_set_value(gc, off, val);
	return 0;
}

#ifdef CONFIG_GPIO_MAX732X_IRQ
static int max732x_writew(struct max732x_chip *chip, uint16_t val)
{
	int ret;

	val = cpu_to_le16(val);

	ret = i2c_master_send(chip->client_group_a, (char *)&val, 2);
	if (ret < 0) {
		dev_err(&chip->client_group_a->dev, "failed writing\n");
		return ret;
	}

	return 0;
}

static int max732x_readw(struct max732x_chip *chip, uint16_t *val)
{
	int ret;

	ret = i2c_master_recv(chip->client_group_a, (char *)val, 2);
	if (ret < 0) {
		dev_err(&chip->client_group_a->dev, "failed reading\n");
		return ret;
	}

	*val = le16_to_cpu(*val);
	return 0;
}

static void max732x_irq_update_mask(struct max732x_chip *chip)
{
	uint16_t msg;

	if (chip->irq_mask == chip->irq_mask_cur)
		return;

	chip->irq_mask = chip->irq_mask_cur;

	if (chip->irq_features == INT_NO_MASK)
		return;

	mutex_lock(&chip->lock);

	switch (chip->irq_features) {
	case INT_INDEP_MASK:
		msg = (chip->irq_mask << 8) | chip->reg_out[0];
		max732x_writew(chip, msg);
		break;

	case INT_MERGED_MASK:
		msg = chip->irq_mask | chip->reg_out[0];
		max732x_writeb(chip, 1, (uint8_t)msg);
		break;
	}

	mutex_unlock(&chip->lock);
}

static int max732x_gpio_to_irq(struct gpio_chip *gc, unsigned off)
{
	struct max732x_chip *chip;

	chip = container_of(gc, struct max732x_chip, gpio_chip);
	return chip->irq_base + off;
}

static void max732x_irq_mask(struct irq_data *d)
{
	struct max732x_chip *chip = irq_data_get_irq_chip_data(d);

	chip->irq_mask_cur &= ~(1 << (d->irq - chip->irq_base));
}

static void max732x_irq_unmask(struct irq_data *d)
{
	struct max732x_chip *chip = irq_data_get_irq_chip_data(d);

	chip->irq_mask_cur |= 1 << (d->irq - chip->irq_base);
}

static void max732x_irq_bus_lock(struct irq_data *d)
{
	struct max732x_chip *chip = irq_data_get_irq_chip_data(d);

	mutex_lock(&chip->irq_lock);
	chip->irq_mask_cur = chip->irq_mask;
}

static void max732x_irq_bus_sync_unlock(struct irq_data *d)
{
	struct max732x_chip *chip = irq_data_get_irq_chip_data(d);

	max732x_irq_update_mask(chip);
	mutex_unlock(&chip->irq_lock);
}

static int max732x_irq_set_type(struct irq_data *d, unsigned int type)
{
	struct max732x_chip *chip = irq_data_get_irq_chip_data(d);
	uint16_t off = d->irq - chip->irq_base;
	uint16_t mask = 1 << off;

	if (!(mask & chip->dir_input)) {
		dev_dbg(&chip->client->dev, "%s port %d is output only\n",
			chip->client->name, off);
		return -EACCES;
	}

	if (!(type & IRQ_TYPE_EDGE_BOTH)) {
		dev_err(&chip->client->dev, "irq %d: unsupported type %d\n",
			d->irq, type);
		return -EINVAL;
	}

	if (type & IRQ_TYPE_EDGE_FALLING)
		chip->irq_trig_fall |= mask;
	else
		chip->irq_trig_fall &= ~mask;

	if (type & IRQ_TYPE_EDGE_RISING)
		chip->irq_trig_raise |= mask;
	else
		chip->irq_trig_raise &= ~mask;

	return max732x_gpio_direction_input(&chip->gpio_chip, off);
}

static struct irq_chip max732x_irq_chip = {
	.name			= "max732x",
	.irq_mask		= max732x_irq_mask,
	.irq_unmask		= max732x_irq_unmask,
	.irq_bus_lock		= max732x_irq_bus_lock,
	.irq_bus_sync_unlock	= max732x_irq_bus_sync_unlock,
	.irq_set_type		= max732x_irq_set_type,
};

static uint8_t max732x_irq_pending(struct max732x_chip *chip)
{
	uint8_t cur_stat;
	uint8_t old_stat;
	uint8_t trigger;
	uint8_t pending;
	uint16_t status;
	int ret;

	ret = max732x_readw(chip, &status);
	if (ret)
		return 0;

	trigger = status >> 8;
	trigger &= chip->irq_mask;

	if (!trigger)
		return 0;

	cur_stat = status & 0xFF;
	cur_stat &= chip->irq_mask;

	old_stat = cur_stat ^ trigger;

	pending = (old_stat & chip->irq_trig_fall) |
		  (cur_stat & chip->irq_trig_raise);
	pending &= trigger;

	return pending;
}

static irqreturn_t max732x_irq_handler(int irq, void *devid)
{
	struct max732x_chip *chip = devid;
	uint8_t pending;
	uint8_t level;

	pending = max732x_irq_pending(chip);

	if (!pending)
		return IRQ_HANDLED;

	do {
		level = __ffs(pending);
		handle_nested_irq(level + chip->irq_base);

		pending &= ~(1 << level);
	} while (pending);

	return IRQ_HANDLED;
}

static int max732x_irq_setup(struct max732x_chip *chip,
			     const struct i2c_device_id *id)
{
	struct i2c_client *client = chip->client;
	struct max732x_platform_data *pdata = dev_get_platdata(&client->dev);
	int has_irq = max732x_features[id->driver_data] >> 32;
	int ret;

	if (pdata->irq_base && has_irq != INT_NONE) {
		int lvl;

		chip->irq_base = pdata->irq_base;
		chip->irq_features = has_irq;
		mutex_init(&chip->irq_lock);

		for (lvl = 0; lvl < chip->gpio_chip.ngpio; lvl++) {
			int irq = lvl + chip->irq_base;

			if (!(chip->dir_input & (1 << lvl)))
				continue;

			irq_set_chip_data(irq, chip);
			irq_set_chip_and_handler(irq, &max732x_irq_chip,
						 handle_edge_irq);
			irq_set_nested_thread(irq, 1);
#ifdef CONFIG_ARM
			set_irq_flags(irq, IRQF_VALID);
#else
			irq_set_noprobe(irq);
#endif
		}

		ret = request_threaded_irq(client->irq,
					   NULL,
					   max732x_irq_handler,
					   IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
					   dev_name(&client->dev), chip);
		if (ret) {
			dev_err(&client->dev, "failed to request irq %d\n",
				client->irq);
			goto out_failed;
		}

		chip->gpio_chip.to_irq = max732x_gpio_to_irq;
	}

	return 0;

out_failed:
	chip->irq_base = 0;
	return ret;
}

static void max732x_irq_teardown(struct max732x_chip *chip)
{
	if (chip->irq_base)
		free_irq(chip->client->irq, chip);
}
#else /* CONFIG_GPIO_MAX732X_IRQ */
static int max732x_irq_setup(struct max732x_chip *chip,
			     const struct i2c_device_id *id)
{
	struct i2c_client *client = chip->client;
	struct max732x_platform_data *pdata = dev_get_platdata(&client->dev);
	int has_irq = max732x_features[id->driver_data] >> 32;

	if (pdata->irq_base && has_irq != INT_NONE)
		dev_warn(&client->dev, "interrupt support not compiled in\n");

	return 0;
}

static void max732x_irq_teardown(struct max732x_chip *chip)
{
}
#endif

static int max732x_setup_gpio(struct max732x_chip *chip,
					const struct i2c_device_id *id,
					unsigned gpio_start)
{
	struct gpio_chip *gc = &chip->gpio_chip;
	uint32_t id_data = (uint32_t)max732x_features[id->driver_data];
	int i, port = 0;

	for (i = 0; i < 16; i++, id_data >>= 2) {
		unsigned int mask = 1 << port;

		switch (id_data & 0x3) {
		case PORT_OUTPUT:
			chip->dir_output |= mask;
			break;
		case PORT_INPUT:
			chip->dir_input |= mask;
			break;
		case PORT_OPENDRAIN:
			chip->dir_output |= mask;
			chip->dir_input |= mask;
			break;
		default:
			continue;
		}

		if (i < 8)
			chip->mask_group_a |= mask;
		port++;
	}

	if (chip->dir_input)
		gc->direction_input = max732x_gpio_direction_input;
	if (chip->dir_output) {
		gc->direction_output = max732x_gpio_direction_output;
		gc->set = max732x_gpio_set_value;
	}
	gc->get = max732x_gpio_get_value;
	gc->can_sleep = 1;

	gc->base = gpio_start;
	gc->ngpio = port;
	gc->label = chip->client->name;
	gc->owner = THIS_MODULE;

	return port;
}

static int max732x_probe(struct i2c_client *client,
				   const struct i2c_device_id *id)
{
	struct max732x_platform_data *pdata;
	struct max732x_chip *chip;
	struct i2c_client *c;
	uint16_t addr_a, addr_b;
	int ret, nr_port;

	pdata = dev_get_platdata(&client->dev);
	if (pdata == NULL) {
		dev_dbg(&client->dev, "no platform data\n");
		return -EINVAL;
	}

	chip = devm_kzalloc(&client->dev, sizeof(struct max732x_chip),
			GFP_KERNEL);
	if (chip == NULL)
		return -ENOMEM;
	chip->client = client;

	nr_port = max732x_setup_gpio(chip, id, pdata->gpio_base);

	addr_a = (client->addr & 0x0f) | 0x60;
	addr_b = (client->addr & 0x0f) | 0x50;

	switch (client->addr & 0x70) {
	case 0x60:
		chip->client_group_a = client;
		if (nr_port > 8) {
			c = i2c_new_dummy(client->adapter, addr_b);
			chip->client_group_b = chip->client_dummy = c;
		}
		break;
	case 0x50:
		chip->client_group_b = client;
		if (nr_port > 8) {
			c = i2c_new_dummy(client->adapter, addr_a);
			chip->client_group_a = chip->client_dummy = c;
		}
		break;
	default:
		dev_err(&client->dev, "invalid I2C address specified %02x\n",
				client->addr);
		ret = -EINVAL;
		goto out_failed;
	}

	mutex_init(&chip->lock);

	max732x_readb(chip, is_group_a(chip, 0), &chip->reg_out[0]);
	if (nr_port > 8)
		max732x_readb(chip, is_group_a(chip, 8), &chip->reg_out[1]);

	ret = max732x_irq_setup(chip, id);
	if (ret)
		goto out_failed;

	ret = gpiochip_add(&chip->gpio_chip);
	if (ret)
		goto out_failed;

	if (pdata->setup) {
		ret = pdata->setup(client, chip->gpio_chip.base,
				chip->gpio_chip.ngpio, pdata->context);
		if (ret < 0)
			dev_warn(&client->dev, "setup failed, %d\n", ret);
	}

	i2c_set_clientdata(client, chip);
	return 0;

out_failed:
	max732x_irq_teardown(chip);
	return ret;
}

static int max732x_remove(struct i2c_client *client)
{
	struct max732x_platform_data *pdata = dev_get_platdata(&client->dev);
	struct max732x_chip *chip = i2c_get_clientdata(client);
	int ret;

	if (pdata->teardown) {
		ret = pdata->teardown(client, chip->gpio_chip.base,
				chip->gpio_chip.ngpio, pdata->context);
		if (ret < 0) {
			dev_err(&client->dev, "%s failed, %d\n",
					"teardown", ret);
			return ret;
		}
	}

	ret = gpiochip_remove(&chip->gpio_chip);
	if (ret) {
		dev_err(&client->dev, "%s failed, %d\n",
				"gpiochip_remove()", ret);
		return ret;
	}

	max732x_irq_teardown(chip);

	/* unregister any dummy i2c_client */
	if (chip->client_dummy)
		i2c_unregister_device(chip->client_dummy);

	return 0;
}

static struct i2c_driver max732x_driver = {
	.driver = {
		.name	= "max732x",
		.owner	= THIS_MODULE,
	},
	.probe		= max732x_probe,
	.remove		= max732x_remove,
	.id_table	= max732x_id,
};

static int __init max732x_init(void)
{
	return i2c_add_driver(&max732x_driver);
}
/* register after i2c postcore initcall and before
 * subsys initcalls that may rely on these GPIOs
 */
subsys_initcall(max732x_init);

static void __exit max732x_exit(void)
{
	i2c_del_driver(&max732x_driver);
}
module_exit(max732x_exit);

MODULE_AUTHOR("Eric Miao <[email protected]>");
MODULE_DESCRIPTION("GPIO expander driver for MAX732X");
MODULE_LICENSE("GPL");
Commit	Line	Data
bbcd6d54	1	/*
c103de24	2	* MAX732x I2C Port Expander with 8/16 I/O
bbcd6d54 EM	3	*
	4	* Copyright (C) 2007 Marvell International Ltd.
	5	* Copyright (C) 2008 Jack Ren <[email protected]>
	6	* Copyright (C) 2008 Eric Miao <[email protected]>
	7	*
	8	* Derived from drivers/gpio/pca953x.c
	9	*
	10	* This program is free software; you can redistribute it and/or modify
	11	* it under the terms of the GNU General Public License as published by
	12	* the Free Software Foundation; version 2 of the License.
	13	*/
	14
	15	#include <linux/module.h>
	16	#include <linux/init.h>
	17	#include <linux/slab.h>
	18	#include <linux/string.h>
	19	#include <linux/gpio.h>
a80a0bbe MZ	20	#include <linux/interrupt.h>
a80a0bbe MZ	21	#include <linux/irq.h>
bbcd6d54 EM	22	#include <linux/i2c.h>
	23	#include <linux/i2c/max732x.h>
	24
	25
	26	/*
	27	* Each port of MAX732x (including MAX7319) falls into one of the
	28	* following three types:
	29	*
	30	* - Push Pull Output
	31	* - Input
	32	* - Open Drain I/O
	33	*
	34	* designated by 'O', 'I' and 'P' individually according to MAXIM's
a80a0bbe MZ	35	* datasheets. 'I' and 'P' ports are interrupt capables, some with
a80a0bbe MZ	36	* a dedicated interrupt mask.
bbcd6d54 EM	37	*
	38	* There are two groups of I/O ports, each group usually includes
	39	* up to 8 I/O ports, and is accessed by a specific I2C address:
	40	*
	41	* - Group A : by I2C address 0b'110xxxx
	42	* - Group B : by I2C address 0b'101xxxx
	43	*
	44	* where 'xxxx' is decided by the connections of pin AD2/AD0. The
	45	* address used also affects the initial state of output signals.
	46	*
	47	* Within each group of ports, there are five known combinations of
	48	* I/O ports: 4I4O, 4P4O, 8I, 8P, 8O, see the definitions below for
a80a0bbe MZ	49	* the detailed organization of these ports. Only Goup A is interrupt
a80a0bbe MZ	50	* capable.
bbcd6d54 EM	51	*
	52	* GPIO numbers start from 'gpio_base + 0' to 'gpio_base + 8/16',
	53	* and GPIOs from GROUP_A are numbered before those from GROUP_B
	54	* (if there are two groups).
	55	*
	56	* NOTE: MAX7328/MAX7329 are drop-in replacements for PCF8574/a, so
	57	* they are not supported by this driver.
	58	*/
	59
	60	#define PORT_NONE 0x0 /* '/' No Port */
	61	#define PORT_OUTPUT 0x1 /* 'O' Push-Pull, Output Only */
	62	#define PORT_INPUT 0x2 /* 'I' Input Only */
	63	#define PORT_OPENDRAIN 0x3 /* 'P' Open-Drain, I/O */
	64
	65	#define IO_4I4O 0x5AA5 /* O7 O6 I5 I4 I3 I2 O1 O0 */
	66	#define IO_4P4O 0x5FF5 /* O7 O6 P5 P4 P3 P2 O1 O0 */
	67	#define IO_8I 0xAAAA /* I7 I6 I5 I4 I3 I2 I1 I0 */
	68	#define IO_8P 0xFFFF /* P7 P6 P5 P4 P3 P2 P1 P0 */
	69	#define IO_8O 0x5555 /* O7 O6 O5 O4 O3 O2 O1 O0 */
	70
	71	#define GROUP_A(x) ((x) & 0xffff) /* I2C Addr: 0b'110xxxx */
	72	#define GROUP_B(x) ((x) << 16) /* I2C Addr: 0b'101xxxx */
	73
a80a0bbe MZ	74	#define INT_NONE 0x0 /* No interrupt capability */
	75	#define INT_NO_MASK 0x1 /* Has interrupts, no mask */
	76	#define INT_INDEP_MASK 0x2 /* Has interrupts, independent mask */
	77	#define INT_MERGED_MASK 0x3 /* Has interrupts, merged mask */
	78
	79	#define INT_CAPS(x) (((uint64_t)(x)) << 32)
	80
	81	enum {
	82	MAX7319,
	83	MAX7320,
	84	MAX7321,
	85	MAX7322,
	86	MAX7323,
	87	MAX7324,
	88	MAX7325,
	89	MAX7326,
	90	MAX7327,
	91	};
	92
	93	static uint64_t max732x_features[] = {
	94	[MAX7319] = GROUP_A(IO_8I) \| INT_CAPS(INT_MERGED_MASK),
	95	[MAX7320] = GROUP_B(IO_8O),
	96	[MAX7321] = GROUP_A(IO_8P) \| INT_CAPS(INT_NO_MASK),
	97	[MAX7322] = GROUP_A(IO_4I4O) \| INT_CAPS(INT_MERGED_MASK),
	98	[MAX7323] = GROUP_A(IO_4P4O) \| INT_CAPS(INT_INDEP_MASK),
	99	[MAX7324] = GROUP_A(IO_8I) \| GROUP_B(IO_8O) \| INT_CAPS(INT_MERGED_MASK),
	100	[MAX7325] = GROUP_A(IO_8P) \| GROUP_B(IO_8O) \| INT_CAPS(INT_NO_MASK),
	101	[MAX7326] = GROUP_A(IO_4I4O) \| GROUP_B(IO_8O) \| INT_CAPS(INT_MERGED_MASK),
	102	[MAX7327] = GROUP_A(IO_4P4O) \| GROUP_B(IO_8O) \| INT_CAPS(INT_NO_MASK),
	103	};
	104
bbcd6d54	105	static const struct i2c_device_id max732x_id[] = {
a80a0bbe MZ	106	{ "max7319", MAX7319 },
	107	{ "max7320", MAX7320 },
	108	{ "max7321", MAX7321 },
	109	{ "max7322", MAX7322 },
	110	{ "max7323", MAX7323 },
	111	{ "max7324", MAX7324 },
	112	{ "max7325", MAX7325 },
	113	{ "max7326", MAX7326 },
	114	{ "max7327", MAX7327 },
bbcd6d54 EM	115	{ },
	116	};
	117	MODULE_DEVICE_TABLE(i2c, max732x_id);
	118
	119	struct max732x_chip {
	120	struct gpio_chip gpio_chip;
	121
	122	struct i2c_client client; / "main" client */
	123	struct i2c_client *client_dummy;
	124	struct i2c_client *client_group_a;
	125	struct i2c_client *client_group_b;
	126
	127	unsigned int mask_group_a;
	128	unsigned int dir_input;
	129	unsigned int dir_output;
	130
	131	struct mutex lock;
	132	uint8_t reg_out[2];
a80a0bbe MZ	133
	134	#ifdef CONFIG_GPIO_MAX732X_IRQ
	135	struct mutex irq_lock;
	136	int irq_base;
	137	uint8_t irq_mask;
	138	uint8_t irq_mask_cur;
	139	uint8_t irq_trig_raise;
	140	uint8_t irq_trig_fall;
	141	uint8_t irq_features;
	142	#endif
bbcd6d54 EM	143	};
bbcd6d54 EM	144
a80a0bbe	145	static int max732x_writeb(struct max732x_chip *chip, int group_a, uint8_t val)
bbcd6d54 EM	146	{
	147	struct i2c_client *client;
	148	int ret;
	149
	150	client = group_a ? chip->client_group_a : chip->client_group_b;
	151	ret = i2c_smbus_write_byte(client, val);
	152	if (ret < 0) {
	153	dev_err(&client->dev, "failed writing\n");
	154	return ret;
	155	}
	156
	157	return 0;
	158	}
	159
a80a0bbe	160	static int max732x_readb(struct max732x_chip chip, int group_a, uint8_t val)
bbcd6d54 EM	161	{
	162	struct i2c_client *client;
	163	int ret;
	164
	165	client = group_a ? chip->client_group_a : chip->client_group_b;
	166	ret = i2c_smbus_read_byte(client);
	167	if (ret < 0) {
	168	dev_err(&client->dev, "failed reading\n");
	169	return ret;
	170	}
	171
	172	*val = (uint8_t)ret;
	173	return 0;
	174	}
	175
	176	static inline int is_group_a(struct max732x_chip *chip, unsigned off)
	177	{
	178	return (1u << off) & chip->mask_group_a;
	179	}
	180
	181	static int max732x_gpio_get_value(struct gpio_chip *gc, unsigned off)
	182	{
	183	struct max732x_chip *chip;
	184	uint8_t reg_val;
	185	int ret;
	186
	187	chip = container_of(gc, struct max732x_chip, gpio_chip);
	188
a80a0bbe	189	ret = max732x_readb(chip, is_group_a(chip, off), &reg_val);
bbcd6d54 EM	190	if (ret < 0)
	191	return 0;
	192
	193	return reg_val & (1u << (off & 0x7));
	194	}
	195
	196	static void max732x_gpio_set_value(struct gpio_chip *gc, unsigned off, int val)
	197	{
	198	struct max732x_chip *chip;
	199	uint8_t reg_out, mask = 1u << (off & 0x7);
	200	int ret;
	201
	202	chip = container_of(gc, struct max732x_chip, gpio_chip);
	203
	204	mutex_lock(&chip->lock);
	205
	206	reg_out = (off > 7) ? chip->reg_out[1] : chip->reg_out[0];
	207	reg_out = (val) ? reg_out \| mask : reg_out & ~mask;
	208
a80a0bbe	209	ret = max732x_writeb(chip, is_group_a(chip, off), reg_out);
bbcd6d54 EM	210	if (ret < 0)
	211	goto out;
	212
	213	/* update the shadow register then */
	214	if (off > 7)
	215	chip->reg_out[1] = reg_out;
	216	else
	217	chip->reg_out[0] = reg_out;
	218	out:
	219	mutex_unlock(&chip->lock);
	220	}
	221
	222	static int max732x_gpio_direction_input(struct gpio_chip *gc, unsigned off)
	223	{
	224	struct max732x_chip *chip;
	225	unsigned int mask = 1u << off;
	226
	227	chip = container_of(gc, struct max732x_chip, gpio_chip);
	228
	229	if ((mask & chip->dir_input) == 0) {
	230	dev_dbg(&chip->client->dev, "%s port %d is output only\n",
	231	chip->client->name, off);
	232	return -EACCES;
	233	}
	234
a13c1868 MZ	235	/*
	236	* Open-drain pins must be set to high impedance (which is
	237	* equivalent to output-high) to be turned into an input.
	238	*/
	239	if ((mask & chip->dir_output))
	240	max732x_gpio_set_value(gc, off, 1);
	241
bbcd6d54 EM	242	return 0;
	243	}
	244
	245	static int max732x_gpio_direction_output(struct gpio_chip *gc,
	246	unsigned off, int val)
	247	{
	248	struct max732x_chip *chip;
	249	unsigned int mask = 1u << off;
	250
	251	chip = container_of(gc, struct max732x_chip, gpio_chip);
	252
	253	if ((mask & chip->dir_output) == 0) {
	254	dev_dbg(&chip->client->dev, "%s port %d is input only\n",
	255	chip->client->name, off);
	256	return -EACCES;
	257	}
	258
	259	max732x_gpio_set_value(gc, off, val);
	260	return 0;
	261	}
	262
a80a0bbe MZ	263	#ifdef CONFIG_GPIO_MAX732X_IRQ
	264	static int max732x_writew(struct max732x_chip *chip, uint16_t val)
	265	{
	266	int ret;
	267
	268	val = cpu_to_le16(val);
	269
	270	ret = i2c_master_send(chip->client_group_a, (char *)&val, 2);
	271	if (ret < 0) {
	272	dev_err(&chip->client_group_a->dev, "failed writing\n");
	273	return ret;
	274	}
	275
	276	return 0;
	277	}
	278
	279	static int max732x_readw(struct max732x_chip chip, uint16_t val)
	280	{
	281	int ret;
	282
	283	ret = i2c_master_recv(chip->client_group_a, (char *)val, 2);
	284	if (ret < 0) {
	285	dev_err(&chip->client_group_a->dev, "failed reading\n");
	286	return ret;
	287	}
	288
	289	val = le16_to_cpu(val);
	290	return 0;
	291	}
	292
	293	static void max732x_irq_update_mask(struct max732x_chip *chip)
	294	{
	295	uint16_t msg;
	296
	297	if (chip->irq_mask == chip->irq_mask_cur)
	298	return;
	299
	300	chip->irq_mask = chip->irq_mask_cur;
	301
	302	if (chip->irq_features == INT_NO_MASK)
	303	return;
	304
	305	mutex_lock(&chip->lock);
	306
	307	switch (chip->irq_features) {
	308	case INT_INDEP_MASK:
	309	msg = (chip->irq_mask << 8) \| chip->reg_out[0];
	310	max732x_writew(chip, msg);
	311	break;
	312
	313	case INT_MERGED_MASK:
	314	msg = chip->irq_mask \| chip->reg_out[0];
	315	max732x_writeb(chip, 1, (uint8_t)msg);
	316	break;
	317	}
	318
	319	mutex_unlock(&chip->lock);
	320	}
	321
	322	static int max732x_gpio_to_irq(struct gpio_chip *gc, unsigned off)
	323	{
	324	struct max732x_chip *chip;
	325
	326	chip = container_of(gc, struct max732x_chip, gpio_chip);
327	return chip->irq_base + off;
328	}
329
fbc4667a	330	static void max732x_irq_mask(struct irq_data *d)
a80a0bbe	331	{
fbc4667a	332	struct max732x_chip *chip = irq_data_get_irq_chip_data(d);
a80a0bbe	333
fbc4667a	334	chip->irq_mask_cur &= ~(1 << (d->irq - chip->irq_base));
a80a0bbe MZ	335	}
a80a0bbe MZ	336
fbc4667a	337	static void max732x_irq_unmask(struct irq_data *d)
a80a0bbe	338	{
fbc4667a	339	struct max732x_chip *chip = irq_data_get_irq_chip_data(d);
a80a0bbe	340
fbc4667a	341	chip->irq_mask_cur \|= 1 << (d->irq - chip->irq_base);
a80a0bbe MZ	342	}
a80a0bbe MZ	343
fbc4667a	344	static void max732x_irq_bus_lock(struct irq_data *d)
a80a0bbe	345	{
fbc4667a	346	struct max732x_chip *chip = irq_data_get_irq_chip_data(d);
a80a0bbe MZ	347
	348	mutex_lock(&chip->irq_lock);
	349	chip->irq_mask_cur = chip->irq_mask;
	350	}
	351
fbc4667a	352	static void max732x_irq_bus_sync_unlock(struct irq_data *d)
a80a0bbe	353	{
fbc4667a	354	struct max732x_chip *chip = irq_data_get_irq_chip_data(d);
a80a0bbe MZ	355
	356	max732x_irq_update_mask(chip);
	357	mutex_unlock(&chip->irq_lock);
	358	}
	359
fbc4667a	360	static int max732x_irq_set_type(struct irq_data *d, unsigned int type)
a80a0bbe	361	{
fbc4667a LB	362	struct max732x_chip *chip = irq_data_get_irq_chip_data(d);
fbc4667a LB	363	uint16_t off = d->irq - chip->irq_base;
a80a0bbe MZ	364	uint16_t mask = 1 << off;
	365
	366	if (!(mask & chip->dir_input)) {
	367	dev_dbg(&chip->client->dev, "%s port %d is output only\n",
	368	chip->client->name, off);
	369	return -EACCES;
	370	}
	371
	372	if (!(type & IRQ_TYPE_EDGE_BOTH)) {
	373	dev_err(&chip->client->dev, "irq %d: unsupported type %d\n",
fbc4667a	374	d->irq, type);
a80a0bbe MZ	375	return -EINVAL;
	376	}
	377
	378	if (type & IRQ_TYPE_EDGE_FALLING)
	379	chip->irq_trig_fall \|= mask;
	380	else
	381	chip->irq_trig_fall &= ~mask;
	382
	383	if (type & IRQ_TYPE_EDGE_RISING)
	384	chip->irq_trig_raise \|= mask;
	385	else
	386	chip->irq_trig_raise &= ~mask;
	387
	388	return max732x_gpio_direction_input(&chip->gpio_chip, off);
	389	}
	390
	391	static struct irq_chip max732x_irq_chip = {
	392	.name = "max732x",
fbc4667a LB	393	.irq_mask = max732x_irq_mask,
	394	.irq_unmask = max732x_irq_unmask,
	395	.irq_bus_lock = max732x_irq_bus_lock,
	396	.irq_bus_sync_unlock = max732x_irq_bus_sync_unlock,
	397	.irq_set_type = max732x_irq_set_type,
a80a0bbe MZ	398	};
	399
	400	static uint8_t max732x_irq_pending(struct max732x_chip *chip)
	401	{
	402	uint8_t cur_stat;
	403	uint8_t old_stat;
	404	uint8_t trigger;
	405	uint8_t pending;
	406	uint16_t status;
	407	int ret;
	408
	409	ret = max732x_readw(chip, &status);
	410	if (ret)
	411	return 0;
	412
	413	trigger = status >> 8;
	414	trigger &= chip->irq_mask;
	415
	416	if (!trigger)
	417	return 0;
	418
	419	cur_stat = status & 0xFF;
	420	cur_stat &= chip->irq_mask;
	421
	422	old_stat = cur_stat ^ trigger;
	423
	424	pending = (old_stat & chip->irq_trig_fall) \|
	425	(cur_stat & chip->irq_trig_raise);
	426	pending &= trigger;
	427
	428	return pending;
	429	}
	430
	431	static irqreturn_t max732x_irq_handler(int irq, void *devid)
	432	{
	433	struct max732x_chip *chip = devid;
	434	uint8_t pending;
	435	uint8_t level;
	436
	437	pending = max732x_irq_pending(chip);
	438
	439	if (!pending)
	440	return IRQ_HANDLED;
	441
	442	do {
	443	level = __ffs(pending);
	444	handle_nested_irq(level + chip->irq_base);
	445
	446	pending &= ~(1 << level);
	447	} while (pending);
	448
	449	return IRQ_HANDLED;
	450	}
	451
	452	static int max732x_irq_setup(struct max732x_chip *chip,
	453	const struct i2c_device_id *id)
	454	{
	455	struct i2c_client *client = chip->client;
e56aee18	456	struct max732x_platform_data *pdata = dev_get_platdata(&client->dev);
a80a0bbe MZ	457	int has_irq = max732x_features[id->driver_data] >> 32;
	458	int ret;
	459
	460	if (pdata->irq_base && has_irq != INT_NONE) {
	461	int lvl;
	462
	463	chip->irq_base = pdata->irq_base;
	464	chip->irq_features = has_irq;
	465	mutex_init(&chip->irq_lock);
	466
	467	for (lvl = 0; lvl < chip->gpio_chip.ngpio; lvl++) {
	468	int irq = lvl + chip->irq_base;
	469
	470	if (!(chip->dir_input & (1 << lvl)))
	471	continue;
	472
b51804bc TG	473	irq_set_chip_data(irq, chip);
b51804bc TG	474	irq_set_chip_and_handler(irq, &max732x_irq_chip,
a80a0bbe	475	handle_edge_irq);
b51804bc	476	irq_set_nested_thread(irq, 1);
a80a0bbe MZ	477	#ifdef CONFIG_ARM
	478	set_irq_flags(irq, IRQF_VALID);
	479	#else
b51804bc	480	irq_set_noprobe(irq);
a80a0bbe MZ	481	#endif
	482	}
	483
	484	ret = request_threaded_irq(client->irq,
	485	NULL,
	486	max732x_irq_handler,
	487	IRQF_TRIGGER_FALLING \| IRQF_ONESHOT,
	488	dev_name(&client->dev), chip);
	489	if (ret) {
	490	dev_err(&client->dev, "failed to request irq %d\n",
	491	client->irq);
	492	goto out_failed;
	493	}
	494
	495	chip->gpio_chip.to_irq = max732x_gpio_to_irq;
	496	}
	497
	498	return 0;
	499
	500	out_failed:
	501	chip->irq_base = 0;
	502	return ret;
	503	}
	504
	505	static void max732x_irq_teardown(struct max732x_chip *chip)
	506	{
	507	if (chip->irq_base)
	508	free_irq(chip->client->irq, chip);
	509	}
	510	#else /* CONFIG_GPIO_MAX732X_IRQ */
	511	static int max732x_irq_setup(struct max732x_chip *chip,
	512	const struct i2c_device_id *id)
	513	{
	514	struct i2c_client *client = chip->client;
e56aee18	515	struct max732x_platform_data *pdata = dev_get_platdata(&client->dev);
a80a0bbe MZ	516	int has_irq = max732x_features[id->driver_data] >> 32;
	517
	518	if (pdata->irq_base && has_irq != INT_NONE)
	519	dev_warn(&client->dev, "interrupt support not compiled in\n");
	520
	521	return 0;
	522	}
	523
	524	static void max732x_irq_teardown(struct max732x_chip *chip)
	525	{
	526	}
	527	#endif
	528
3836309d	529	static int max732x_setup_gpio(struct max732x_chip *chip,
bbcd6d54 EM	530	const struct i2c_device_id *id,
	531	unsigned gpio_start)
	532	{
	533	struct gpio_chip *gc = &chip->gpio_chip;
a80a0bbe	534	uint32_t id_data = (uint32_t)max732x_features[id->driver_data];
bbcd6d54 EM	535	int i, port = 0;
	536
	537	for (i = 0; i < 16; i++, id_data >>= 2) {
	538	unsigned int mask = 1 << port;
	539
	540	switch (id_data & 0x3) {
	541	case PORT_OUTPUT:
	542	chip->dir_output \|= mask;
	543	break;
	544	case PORT_INPUT:
	545	chip->dir_input \|= mask;
	546	break;
	547	case PORT_OPENDRAIN:
	548	chip->dir_output \|= mask;
	549	chip->dir_input \|= mask;
	550	break;
	551	default:
	552	continue;
	553	}
	554
	555	if (i < 8)
	556	chip->mask_group_a \|= mask;
	557	port++;
	558	}
	559
	560	if (chip->dir_input)
	561	gc->direction_input = max732x_gpio_direction_input;
	562	if (chip->dir_output) {
	563	gc->direction_output = max732x_gpio_direction_output;
	564	gc->set = max732x_gpio_set_value;
	565	}
	566	gc->get = max732x_gpio_get_value;
	567	gc->can_sleep = 1;
	568
	569	gc->base = gpio_start;
	570	gc->ngpio = port;
	571	gc->label = chip->client->name;
	572	gc->owner = THIS_MODULE;
	573
	574	return port;
	575	}
	576
3836309d	577	static int max732x_probe(struct i2c_client *client,
bbcd6d54 EM	578	const struct i2c_device_id *id)
	579	{
	580	struct max732x_platform_data *pdata;
	581	struct max732x_chip *chip;
	582	struct i2c_client *c;
	583	uint16_t addr_a, addr_b;
	584	int ret, nr_port;
	585
e56aee18	586	pdata = dev_get_platdata(&client->dev);
a342d215 BD	587	if (pdata == NULL) {
	588	dev_dbg(&client->dev, "no platform data\n");
	589	return -EINVAL;
	590	}
bbcd6d54	591
b09638a4 JH	592	chip = devm_kzalloc(&client->dev, sizeof(struct max732x_chip),
b09638a4 JH	593	GFP_KERNEL);
bbcd6d54 EM	594	if (chip == NULL)
	595	return -ENOMEM;
	596	chip->client = client;
	597
	598	nr_port = max732x_setup_gpio(chip, id, pdata->gpio_base);
	599
	600	addr_a = (client->addr & 0x0f) \| 0x60;
	601	addr_b = (client->addr & 0x0f) \| 0x50;
	602
	603	switch (client->addr & 0x70) {
	604	case 0x60:
	605	chip->client_group_a = client;
5535cb68	606	if (nr_port > 8) {
bbcd6d54 EM	607	c = i2c_new_dummy(client->adapter, addr_b);
	608	chip->client_group_b = chip->client_dummy = c;
	609	}
	610	break;
	611	case 0x50:
	612	chip->client_group_b = client;
5535cb68	613	if (nr_port > 8) {
bbcd6d54 EM	614	c = i2c_new_dummy(client->adapter, addr_a);
	615	chip->client_group_a = chip->client_dummy = c;
	616	}
	617	break;
	618	default:
	619	dev_err(&client->dev, "invalid I2C address specified %02x\n",
	620	client->addr);
	621	ret = -EINVAL;
	622	goto out_failed;
	623	}
	624
	625	mutex_init(&chip->lock);
	626
a80a0bbe	627	max732x_readb(chip, is_group_a(chip, 0), &chip->reg_out[0]);
5535cb68	628	if (nr_port > 8)
a80a0bbe MZ	629	max732x_readb(chip, is_group_a(chip, 8), &chip->reg_out[1]);
	630
	631	ret = max732x_irq_setup(chip, id);
	632	if (ret)
	633	goto out_failed;
bbcd6d54 EM	634
	635	ret = gpiochip_add(&chip->gpio_chip);
	636	if (ret)
	637	goto out_failed;
	638
	639	if (pdata->setup) {
	640	ret = pdata->setup(client, chip->gpio_chip.base,
	641	chip->gpio_chip.ngpio, pdata->context);
	642	if (ret < 0)
	643	dev_warn(&client->dev, "setup failed, %d\n", ret);
	644	}
	645
	646	i2c_set_clientdata(client, chip);
	647	return 0;
	648
	649	out_failed:
a80a0bbe	650	max732x_irq_teardown(chip);
bbcd6d54 EM	651	return ret;
	652	}
	653
206210ce	654	static int max732x_remove(struct i2c_client *client)
bbcd6d54	655	{
e56aee18	656	struct max732x_platform_data *pdata = dev_get_platdata(&client->dev);
bbcd6d54 EM	657	struct max732x_chip *chip = i2c_get_clientdata(client);
	658	int ret;
	659
	660	if (pdata->teardown) {
	661	ret = pdata->teardown(client, chip->gpio_chip.base,
	662	chip->gpio_chip.ngpio, pdata->context);
	663	if (ret < 0) {
	664	dev_err(&client->dev, "%s failed, %d\n",
	665	"teardown", ret);
	666	return ret;
	667	}
	668	}
	669
	670	ret = gpiochip_remove(&chip->gpio_chip);
	671	if (ret) {
	672	dev_err(&client->dev, "%s failed, %d\n",
	673	"gpiochip_remove()", ret);
	674	return ret;
	675	}
	676
a80a0bbe MZ	677	max732x_irq_teardown(chip);
a80a0bbe MZ	678
bbcd6d54 EM	679	/* unregister any dummy i2c_client */
	680	if (chip->client_dummy)
	681	i2c_unregister_device(chip->client_dummy);
	682
bbcd6d54 EM	683	return 0;
	684	}
	685
	686	static struct i2c_driver max732x_driver = {
	687	.driver = {
	688	.name = "max732x",
	689	.owner = THIS_MODULE,
	690	},
	691	.probe = max732x_probe,
8283c4ff	692	.remove = max732x_remove,
bbcd6d54 EM	693	.id_table = max732x_id,
	694	};
	695
	696	static int __init max732x_init(void)
	697	{
	698	return i2c_add_driver(&max732x_driver);
	699	}
2f8d1197 DB	700	/* register after i2c postcore initcall and before
	701	* subsys initcalls that may rely on these GPIOs
	702	*/
	703	subsys_initcall(max732x_init);
bbcd6d54 EM	704
	705	static void __exit max732x_exit(void)
	706	{
	707	i2c_del_driver(&max732x_driver);
	708	}
	709	module_exit(max732x_exit);
	710
	711	MODULE_AUTHOR("Eric Miao <[email protected]>");
	712	MODULE_DESCRIPTION("GPIO expander driver for MAX732X");
	713	MODULE_LICENSE("GPL");