[net-next-2.6.git] / drivers / gpio / pca953x.c

/*
 *  pca953x.c - 4/8/16 bit I/O ports
 *
 *  Copyright (C) 2005 Ben Gardner <bgardner@wabtec.com>
 *  Copyright (C) 2007 Marvell International Ltd.
 *
 *  Derived from drivers/i2c/chips/pca9539.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/gpio.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/i2c.h>
#include <linux/i2c/pca953x.h>
#include <linux/slab.h>
#ifdef CONFIG_OF_GPIO
#include <linux/of_platform.h>
#include <linux/of_gpio.h>
#endif

#define PCA953X_INPUT          0
#define PCA953X_OUTPUT         1
#define PCA953X_INVERT         2
#define PCA953X_DIRECTION      3

#define PCA953X_GPIOS	       0x00FF
#define PCA953X_INT	       0x0100

static const struct i2c_device_id pca953x_id[] = {
	{ "pca9534", 8  | PCA953X_INT, },
	{ "pca9535", 16 | PCA953X_INT, },
	{ "pca9536", 4, },
	{ "pca9537", 4  | PCA953X_INT, },
	{ "pca9538", 8  | PCA953X_INT, },
	{ "pca9539", 16 | PCA953X_INT, },
	{ "pca9554", 8  | PCA953X_INT, },
	{ "pca9555", 16 | PCA953X_INT, },
	{ "pca9556", 8, },
	{ "pca9557", 8, },

	{ "max7310", 8, },
	{ "max7312", 16 | PCA953X_INT, },
	{ "max7313", 16 | PCA953X_INT, },
	{ "max7315", 8  | PCA953X_INT, },
	{ "pca6107", 8  | PCA953X_INT, },
	{ "tca6408", 8  | PCA953X_INT, },
	{ "tca6416", 16 | PCA953X_INT, },
	/* NYET:  { "tca6424", 24, }, */
	{ }
};
MODULE_DEVICE_TABLE(i2c, pca953x_id);

struct pca953x_chip {
	unsigned gpio_start;
	uint16_t reg_output;
	uint16_t reg_direction;

#ifdef CONFIG_GPIO_PCA953X_IRQ
	struct mutex irq_lock;
	uint16_t irq_mask;
	uint16_t irq_stat;
	uint16_t irq_trig_raise;
	uint16_t irq_trig_fall;
	int	 irq_base;
#endif

	struct i2c_client *client;
	struct pca953x_platform_data *dyn_pdata;
	struct gpio_chip gpio_chip;
	const char *const *names;
};

static int pca953x_write_reg(struct pca953x_chip *chip, int reg, uint16_t val)
{
	int ret;

	if (chip->gpio_chip.ngpio <= 8)
		ret = i2c_smbus_write_byte_data(chip->client, reg, val);
	else
		ret = i2c_smbus_write_word_data(chip->client, reg << 1, val);

	if (ret < 0) {
		dev_err(&chip->client->dev, "failed writing register\n");
		return ret;
	}

	return 0;
}

static int pca953x_read_reg(struct pca953x_chip *chip, int reg, uint16_t *val)
{
	int ret;

	if (chip->gpio_chip.ngpio <= 8)
		ret = i2c_smbus_read_byte_data(chip->client, reg);
	else
		ret = i2c_smbus_read_word_data(chip->client, reg << 1);

	if (ret < 0) {
		dev_err(&chip->client->dev, "failed reading register\n");
		return ret;
	}

	*val = (uint16_t)ret;
	return 0;
}

static int pca953x_gpio_direction_input(struct gpio_chip *gc, unsigned off)
{
	struct pca953x_chip *chip;
	uint16_t reg_val;
	int ret;

	chip = container_of(gc, struct pca953x_chip, gpio_chip);

	reg_val = chip->reg_direction | (1u << off);
	ret = pca953x_write_reg(chip, PCA953X_DIRECTION, reg_val);
	if (ret)
		return ret;

	chip->reg_direction = reg_val;
	return 0;
}

static int pca953x_gpio_direction_output(struct gpio_chip *gc,
		unsigned off, int val)
{
	struct pca953x_chip *chip;
	uint16_t reg_val;
	int ret;

	chip = container_of(gc, struct pca953x_chip, gpio_chip);

	/* set output level */
	if (val)
		reg_val = chip->reg_output | (1u << off);
	else
		reg_val = chip->reg_output & ~(1u << off);

	ret = pca953x_write_reg(chip, PCA953X_OUTPUT, reg_val);
	if (ret)
		return ret;

	chip->reg_output = reg_val;

	/* then direction */
	reg_val = chip->reg_direction & ~(1u << off);
	ret = pca953x_write_reg(chip, PCA953X_DIRECTION, reg_val);
	if (ret)
		return ret;

	chip->reg_direction = reg_val;
	return 0;
}

static int pca953x_gpio_get_value(struct gpio_chip *gc, unsigned off)
{
	struct pca953x_chip *chip;
	uint16_t reg_val;
	int ret;

	chip = container_of(gc, struct pca953x_chip, gpio_chip);

	ret = pca953x_read_reg(chip, PCA953X_INPUT, &reg_val);
	if (ret < 0) {
		/* NOTE:  diagnostic already emitted; that's all we should
		 * do unless gpio_*_value_cansleep() calls become different
		 * from their nonsleeping siblings (and report faults).
		 */
		return 0;
	}

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

static void pca953x_gpio_set_value(struct gpio_chip *gc, unsigned off, int val)
{
	struct pca953x_chip *chip;
	uint16_t reg_val;
	int ret;

	chip = container_of(gc, struct pca953x_chip, gpio_chip);

	if (val)
		reg_val = chip->reg_output | (1u << off);
	else
		reg_val = chip->reg_output & ~(1u << off);

	ret = pca953x_write_reg(chip, PCA953X_OUTPUT, reg_val);
	if (ret)
		return;

	chip->reg_output = reg_val;
}

static void pca953x_setup_gpio(struct pca953x_chip *chip, int gpios)
{
	struct gpio_chip *gc;

	gc = &chip->gpio_chip;

	gc->direction_input  = pca953x_gpio_direction_input;
	gc->direction_output = pca953x_gpio_direction_output;
	gc->get = pca953x_gpio_get_value;
	gc->set = pca953x_gpio_set_value;
	gc->can_sleep = 1;

	gc->base = chip->gpio_start;
	gc->ngpio = gpios;
	gc->label = chip->client->name;
	gc->dev = &chip->client->dev;
	gc->owner = THIS_MODULE;
	gc->names = chip->names;
}

#ifdef CONFIG_GPIO_PCA953X_IRQ
static int pca953x_gpio_to_irq(struct gpio_chip *gc, unsigned off)
{
	struct pca953x_chip *chip;

	chip = container_of(gc, struct pca953x_chip, gpio_chip);
	return chip->irq_base + off;
}

static void pca953x_irq_mask(unsigned int irq)
{
	struct pca953x_chip *chip = get_irq_chip_data(irq);

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

static void pca953x_irq_unmask(unsigned int irq)
{
	struct pca953x_chip *chip = get_irq_chip_data(irq);

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

static void pca953x_irq_bus_lock(unsigned int irq)
{
	struct pca953x_chip *chip = get_irq_chip_data(irq);

	mutex_lock(&chip->irq_lock);
}

static void pca953x_irq_bus_sync_unlock(unsigned int irq)
{
	struct pca953x_chip *chip = get_irq_chip_data(irq);
	uint16_t new_irqs;
	uint16_t level;

	/* Look for any newly setup interrupt */
	new_irqs = chip->irq_trig_fall | chip->irq_trig_raise;
	new_irqs &= ~chip->reg_direction;

	while (new_irqs) {
		level = __ffs(new_irqs);
		pca953x_gpio_direction_input(&chip->gpio_chip, level);
		new_irqs &= ~(1 << level);
	}

	mutex_unlock(&chip->irq_lock);
}

static int pca953x_irq_set_type(unsigned int irq, unsigned int type)
{
	struct pca953x_chip *chip = get_irq_chip_data(irq);
	uint16_t level = irq - chip->irq_base;
	uint16_t mask = 1 << level;

	if (!(type & IRQ_TYPE_EDGE_BOTH)) {
		dev_err(&chip->client->dev, "irq %d: unsupported type %d\n",
			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 0;
}

static struct irq_chip pca953x_irq_chip = {
	.name			= "pca953x",
	.mask			= pca953x_irq_mask,
	.unmask			= pca953x_irq_unmask,
	.bus_lock		= pca953x_irq_bus_lock,
	.bus_sync_unlock	= pca953x_irq_bus_sync_unlock,
	.set_type		= pca953x_irq_set_type,
};

static uint16_t pca953x_irq_pending(struct pca953x_chip *chip)
{
	uint16_t cur_stat;
	uint16_t old_stat;
	uint16_t pending;
	uint16_t trigger;
	int ret;

	ret = pca953x_read_reg(chip, PCA953X_INPUT, &cur_stat);
	if (ret)
		return 0;

	/* Remove output pins from the equation */
	cur_stat &= chip->reg_direction;

	old_stat = chip->irq_stat;
	trigger = (cur_stat ^ old_stat) & chip->irq_mask;

	if (!trigger)
		return 0;

	chip->irq_stat = cur_stat;

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

	return pending;
}

static irqreturn_t pca953x_irq_handler(int irq, void *devid)
{
	struct pca953x_chip *chip = devid;
	uint16_t pending;
	uint16_t level;

	pending = pca953x_irq_pending(chip);

	if (!pending)
		return IRQ_HANDLED;

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

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

	return IRQ_HANDLED;
}

static int pca953x_irq_setup(struct pca953x_chip *chip,
			     const struct i2c_device_id *id)
{
	struct i2c_client *client = chip->client;
	struct pca953x_platform_data *pdata = client->dev.platform_data;
	int ret;

	if (pdata->irq_base != -1
			&& (id->driver_data & PCA953X_INT)) {
		int lvl;

		ret = pca953x_read_reg(chip, PCA953X_INPUT,
				       &chip->irq_stat);
		if (ret)
			goto out_failed;

		/*
		 * There is no way to know which GPIO line generated the
		 * interrupt.  We have to rely on the previous read for
		 * this purpose.
		 */
		chip->irq_stat &= chip->reg_direction;
		chip->irq_base = pdata->irq_base;
		mutex_init(&chip->irq_lock);

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

			set_irq_chip_data(irq, chip);
			set_irq_chip_and_handler(irq, &pca953x_irq_chip,
						 handle_edge_irq);
#ifdef CONFIG_ARM
			set_irq_flags(irq, IRQF_VALID);
#else
			set_irq_noprobe(irq);
#endif
		}

		ret = request_threaded_irq(client->irq,
					   NULL,
					   pca953x_irq_handler,
					   IRQF_TRIGGER_RISING |
					   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 = pca953x_gpio_to_irq;
	}

	return 0;

out_failed:
	chip->irq_base = -1;
	return ret;
}

static void pca953x_irq_teardown(struct pca953x_chip *chip)
{
	if (chip->irq_base != -1)
		free_irq(chip->client->irq, chip);
}
#else /* CONFIG_GPIO_PCA953X_IRQ */
static int pca953x_irq_setup(struct pca953x_chip *chip,
			     const struct i2c_device_id *id)
{
	struct i2c_client *client = chip->client;
	struct pca953x_platform_data *pdata = client->dev.platform_data;

	if (pdata->irq_base != -1 && (id->driver_data & PCA953X_INT))
		dev_warn(&client->dev, "interrupt support not compiled in\n");

	return 0;
}

static void pca953x_irq_teardown(struct pca953x_chip *chip)
{
}
#endif

/*
 * Handlers for alternative sources of platform_data
 */
#ifdef CONFIG_OF_GPIO
/*
 * Translate OpenFirmware node properties into platform_data
 */
static struct pca953x_platform_data *
pca953x_get_alt_pdata(struct i2c_client *client)
{
	struct pca953x_platform_data *pdata;
	struct device_node *node;
	const uint16_t *val;

	node = client->dev.of_node;
	if (node == NULL)
		return NULL;

	pdata = kzalloc(sizeof(struct pca953x_platform_data), GFP_KERNEL);
	if (pdata == NULL) {
		dev_err(&client->dev, "Unable to allocate platform_data\n");
		return NULL;
	}

	pdata->gpio_base = -1;
	val = of_get_property(node, "linux,gpio-base", NULL);
	if (val) {
		if (*val < 0)
			dev_warn(&client->dev,
				 "invalid gpio-base in device tree\n");
		else
			pdata->gpio_base = *val;
	}

	val = of_get_property(node, "polarity", NULL);
	if (val)
		pdata->invert = *val;

	return pdata;
}
#else
static struct pca953x_platform_data *
pca953x_get_alt_pdata(struct i2c_client *client)
{
	return NULL;
}
#endif

static int __devinit pca953x_probe(struct i2c_client *client,
				   const struct i2c_device_id *id)
{
	struct pca953x_platform_data *pdata;
	struct pca953x_chip *chip;
	int ret;

	chip = kzalloc(sizeof(struct pca953x_chip), GFP_KERNEL);
	if (chip == NULL)
		return -ENOMEM;

	pdata = client->dev.platform_data;
	if (pdata == NULL) {
		pdata = pca953x_get_alt_pdata(client);
		/*
		 * Unlike normal platform_data, this is allocated
		 * dynamically and must be freed in the driver
		 */
		chip->dyn_pdata = pdata;
	}

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

	chip->client = client;

	chip->gpio_start = pdata->gpio_base;

	chip->names = pdata->names;

	/* initialize cached registers from their original values.
	 * we can't share this chip with another i2c master.
	 */
	pca953x_setup_gpio(chip, id->driver_data & PCA953X_GPIOS);

	ret = pca953x_read_reg(chip, PCA953X_OUTPUT, &chip->reg_output);
	if (ret)
		goto out_failed;

	ret = pca953x_read_reg(chip, PCA953X_DIRECTION, &chip->reg_direction);
	if (ret)
		goto out_failed;

	/* set platform specific polarity inversion */
	ret = pca953x_write_reg(chip, PCA953X_INVERT, pdata->invert);
	if (ret)
		goto out_failed;

	ret = pca953x_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:
	pca953x_irq_teardown(chip);
	kfree(chip->dyn_pdata);
	kfree(chip);
	return ret;
}

static int pca953x_remove(struct i2c_client *client)
{
	struct pca953x_platform_data *pdata = client->dev.platform_data;
	struct pca953x_chip *chip = i2c_get_clientdata(client);
	int ret = 0;

	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;
	}

	pca953x_irq_teardown(chip);
	kfree(chip->dyn_pdata);
	kfree(chip);
	return 0;
}

static struct i2c_driver pca953x_driver = {
	.driver = {
		.name	= "pca953x",
	},
	.probe		= pca953x_probe,
	.remove		= pca953x_remove,
	.id_table	= pca953x_id,
};

static int __init pca953x_init(void)
{
	return i2c_add_driver(&pca953x_driver);
}
/* register after i2c postcore initcall and before
 * subsys initcalls that may rely on these GPIOs
 */
subsys_initcall(pca953x_init);

static void __exit pca953x_exit(void)
{
	i2c_del_driver(&pca953x_driver);
}
module_exit(pca953x_exit);

MODULE_AUTHOR("eric miao <eric.miao@marvell.com>");
MODULE_DESCRIPTION("GPIO expander driver for PCA953x");
MODULE_LICENSE("GPL");
Commit	Line	Data
9e60fdcf	1	/*
f5e8ff48	2	* pca953x.c - 4/8/16 bit I/O ports
9e60fdcf	3	*
	4	* Copyright (C) 2005 Ben Gardner <bgardner@wabtec.com>
	5	* Copyright (C) 2007 Marvell International Ltd.
	6	*
	7	* Derived from drivers/i2c/chips/pca9539.c
	8	*
	9	* This program is free software; you can redistribute it and/or modify
	10	* it under the terms of the GNU General Public License as published by
	11	* the Free Software Foundation; version 2 of the License.
	12	*/
	13
	14	#include <linux/module.h>
	15	#include <linux/init.h>
d120c17f	16	#include <linux/gpio.h>
89ea8bbe MZ	17	#include <linux/interrupt.h>
89ea8bbe MZ	18	#include <linux/irq.h>
9e60fdcf	19	#include <linux/i2c.h>
d1c057e3	20	#include <linux/i2c/pca953x.h>
5a0e3ad6	21	#include <linux/slab.h>
1965d303 NC	22	#ifdef CONFIG_OF_GPIO
	23	#include <linux/of_platform.h>
	24	#include <linux/of_gpio.h>
	25	#endif
9e60fdcf	26
f5e8ff48 GL	27	#define PCA953X_INPUT 0
	28	#define PCA953X_OUTPUT 1
	29	#define PCA953X_INVERT 2
	30	#define PCA953X_DIRECTION 3
9e60fdcf	31
89ea8bbe MZ	32	#define PCA953X_GPIOS 0x00FF
	33	#define PCA953X_INT 0x0100
	34
3760f736	35	static const struct i2c_device_id pca953x_id[] = {
89ea8bbe MZ	36	{ "pca9534", 8 \| PCA953X_INT, },
89ea8bbe MZ	37	{ "pca9535", 16 \| PCA953X_INT, },
f5e8ff48	38	{ "pca9536", 4, },
89ea8bbe MZ	39	{ "pca9537", 4 \| PCA953X_INT, },
	40	{ "pca9538", 8 \| PCA953X_INT, },
	41	{ "pca9539", 16 \| PCA953X_INT, },
	42	{ "pca9554", 8 \| PCA953X_INT, },
	43	{ "pca9555", 16 \| PCA953X_INT, },
10dfb54c	44	{ "pca9556", 8, },
f39e5781	45	{ "pca9557", 8, },
ab5dc372	46
7059d4b0	47	{ "max7310", 8, },
89ea8bbe MZ	48	{ "max7312", 16 \| PCA953X_INT, },
	49	{ "max7313", 16 \| PCA953X_INT, },
	50	{ "max7315", 8 \| PCA953X_INT, },
	51	{ "pca6107", 8 \| PCA953X_INT, },
	52	{ "tca6408", 8 \| PCA953X_INT, },
	53	{ "tca6416", 16 \| PCA953X_INT, },
ab5dc372	54	/* NYET: { "tca6424", 24, }, */
3760f736	55	{ }
f5e8ff48	56	};
3760f736	57	MODULE_DEVICE_TABLE(i2c, pca953x_id);
9e60fdcf	58
f3dc3630	59	struct pca953x_chip {
9e60fdcf	60	unsigned gpio_start;
	61	uint16_t reg_output;
	62	uint16_t reg_direction;
	63
89ea8bbe MZ	64	#ifdef CONFIG_GPIO_PCA953X_IRQ
	65	struct mutex irq_lock;
	66	uint16_t irq_mask;
	67	uint16_t irq_stat;
	68	uint16_t irq_trig_raise;
	69	uint16_t irq_trig_fall;
	70	int irq_base;
	71	#endif
	72
9e60fdcf	73	struct i2c_client *client;
1965d303	74	struct pca953x_platform_data *dyn_pdata;
9e60fdcf	75	struct gpio_chip gpio_chip;
62154991	76	const char const names;
9e60fdcf	77	};
9e60fdcf	78
f3dc3630	79	static int pca953x_write_reg(struct pca953x_chip *chip, int reg, uint16_t val)
9e60fdcf	80	{
f5e8ff48 GL	81	int ret;
	82
	83	if (chip->gpio_chip.ngpio <= 8)
	84	ret = i2c_smbus_write_byte_data(chip->client, reg, val);
9e60fdcf	85	else
f5e8ff48 GL	86	ret = i2c_smbus_write_word_data(chip->client, reg << 1, val);
	87
	88	if (ret < 0) {
	89	dev_err(&chip->client->dev, "failed writing register\n");
ab5dc372	90	return ret;
f5e8ff48 GL	91	}
	92
	93	return 0;
9e60fdcf	94	}
9e60fdcf	95
f3dc3630	96	static int pca953x_read_reg(struct pca953x_chip chip, int reg, uint16_t val)
9e60fdcf	97	{
	98	int ret;
	99
f5e8ff48 GL	100	if (chip->gpio_chip.ngpio <= 8)
	101	ret = i2c_smbus_read_byte_data(chip->client, reg);
	102	else
	103	ret = i2c_smbus_read_word_data(chip->client, reg << 1);
	104
9e60fdcf	105	if (ret < 0) {
9e60fdcf	106	dev_err(&chip->client->dev, "failed reading register\n");
ab5dc372	107	return ret;
9e60fdcf	108	}
	109
	110	*val = (uint16_t)ret;
	111	return 0;
	112	}
	113
f3dc3630	114	static int pca953x_gpio_direction_input(struct gpio_chip *gc, unsigned off)
9e60fdcf	115	{
f3dc3630	116	struct pca953x_chip *chip;
9e60fdcf	117	uint16_t reg_val;
	118	int ret;
	119
f3dc3630	120	chip = container_of(gc, struct pca953x_chip, gpio_chip);
9e60fdcf	121
9e60fdcf	122	reg_val = chip->reg_direction \| (1u << off);
f3dc3630	123	ret = pca953x_write_reg(chip, PCA953X_DIRECTION, reg_val);
9e60fdcf	124	if (ret)
	125	return ret;
	126
	127	chip->reg_direction = reg_val;
	128	return 0;
	129	}
	130
f3dc3630	131	static int pca953x_gpio_direction_output(struct gpio_chip *gc,
9e60fdcf	132	unsigned off, int val)
9e60fdcf	133	{
f3dc3630	134	struct pca953x_chip *chip;
9e60fdcf	135	uint16_t reg_val;
	136	int ret;
	137
f3dc3630	138	chip = container_of(gc, struct pca953x_chip, gpio_chip);
9e60fdcf	139
	140	/* set output level */
	141	if (val)
	142	reg_val = chip->reg_output \| (1u << off);
	143	else
	144	reg_val = chip->reg_output & ~(1u << off);
	145
f3dc3630	146	ret = pca953x_write_reg(chip, PCA953X_OUTPUT, reg_val);
9e60fdcf	147	if (ret)
	148	return ret;
	149
	150	chip->reg_output = reg_val;
	151
	152	/* then direction */
	153	reg_val = chip->reg_direction & ~(1u << off);
f3dc3630	154	ret = pca953x_write_reg(chip, PCA953X_DIRECTION, reg_val);
9e60fdcf	155	if (ret)
	156	return ret;
	157
	158	chip->reg_direction = reg_val;
	159	return 0;
	160	}
	161
f3dc3630	162	static int pca953x_gpio_get_value(struct gpio_chip *gc, unsigned off)
9e60fdcf	163	{
f3dc3630	164	struct pca953x_chip *chip;
9e60fdcf	165	uint16_t reg_val;
	166	int ret;
	167
f3dc3630	168	chip = container_of(gc, struct pca953x_chip, gpio_chip);
9e60fdcf	169
f3dc3630	170	ret = pca953x_read_reg(chip, PCA953X_INPUT, &reg_val);
9e60fdcf	171	if (ret < 0) {
	172	/* NOTE: diagnostic already emitted; that's all we should
	173	* do unless gpio_*_value_cansleep() calls become different
	174	* from their nonsleeping siblings (and report faults).
	175	*/
	176	return 0;
	177	}
	178
	179	return (reg_val & (1u << off)) ? 1 : 0;
	180	}
	181
f3dc3630	182	static void pca953x_gpio_set_value(struct gpio_chip *gc, unsigned off, int val)
9e60fdcf	183	{
f3dc3630	184	struct pca953x_chip *chip;
9e60fdcf	185	uint16_t reg_val;
	186	int ret;
	187
f3dc3630	188	chip = container_of(gc, struct pca953x_chip, gpio_chip);
9e60fdcf	189
	190	if (val)
	191	reg_val = chip->reg_output \| (1u << off);
	192	else
	193	reg_val = chip->reg_output & ~(1u << off);
	194
f3dc3630	195	ret = pca953x_write_reg(chip, PCA953X_OUTPUT, reg_val);
9e60fdcf	196	if (ret)
	197	return;
	198
	199	chip->reg_output = reg_val;
	200	}
	201
f5e8ff48	202	static void pca953x_setup_gpio(struct pca953x_chip *chip, int gpios)
9e60fdcf	203	{
	204	struct gpio_chip *gc;
	205
	206	gc = &chip->gpio_chip;
	207
f3dc3630 GL	208	gc->direction_input = pca953x_gpio_direction_input;
	209	gc->direction_output = pca953x_gpio_direction_output;
	210	gc->get = pca953x_gpio_get_value;
	211	gc->set = pca953x_gpio_set_value;
84207805	212	gc->can_sleep = 1;
9e60fdcf	213
9e60fdcf	214	gc->base = chip->gpio_start;
f5e8ff48 GL	215	gc->ngpio = gpios;
f5e8ff48 GL	216	gc->label = chip->client->name;
d8f388d8	217	gc->dev = &chip->client->dev;
d72cbed0	218	gc->owner = THIS_MODULE;
77906a54	219	gc->names = chip->names;
9e60fdcf	220	}
9e60fdcf	221
89ea8bbe MZ	222	#ifdef CONFIG_GPIO_PCA953X_IRQ
	223	static int pca953x_gpio_to_irq(struct gpio_chip *gc, unsigned off)
	224	{
	225	struct pca953x_chip *chip;
	226
	227	chip = container_of(gc, struct pca953x_chip, gpio_chip);
	228	return chip->irq_base + off;
	229	}
	230
	231	static void pca953x_irq_mask(unsigned int irq)
	232	{
	233	struct pca953x_chip *chip = get_irq_chip_data(irq);
	234
	235	chip->irq_mask &= ~(1 << (irq - chip->irq_base));
	236	}
	237
	238	static void pca953x_irq_unmask(unsigned int irq)
	239	{
	240	struct pca953x_chip *chip = get_irq_chip_data(irq);
	241
	242	chip->irq_mask \|= 1 << (irq - chip->irq_base);
	243	}
	244
	245	static void pca953x_irq_bus_lock(unsigned int irq)
	246	{
	247	struct pca953x_chip *chip = get_irq_chip_data(irq);
	248
	249	mutex_lock(&chip->irq_lock);
	250	}
	251
	252	static void pca953x_irq_bus_sync_unlock(unsigned int irq)
	253	{
	254	struct pca953x_chip *chip = get_irq_chip_data(irq);
a2cb9aeb MZ	255	uint16_t new_irqs;
	256	uint16_t level;
	257
	258	/* Look for any newly setup interrupt */
	259	new_irqs = chip->irq_trig_fall \| chip->irq_trig_raise;
	260	new_irqs &= ~chip->reg_direction;
	261
	262	while (new_irqs) {
	263	level = __ffs(new_irqs);
	264	pca953x_gpio_direction_input(&chip->gpio_chip, level);
	265	new_irqs &= ~(1 << level);
	266	}
89ea8bbe MZ	267
	268	mutex_unlock(&chip->irq_lock);
	269	}
	270
	271	static int pca953x_irq_set_type(unsigned int irq, unsigned int type)
	272	{
	273	struct pca953x_chip *chip = get_irq_chip_data(irq);
	274	uint16_t level = irq - chip->irq_base;
	275	uint16_t mask = 1 << level;
	276
	277	if (!(type & IRQ_TYPE_EDGE_BOTH)) {
	278	dev_err(&chip->client->dev, "irq %d: unsupported type %d\n",
	279	irq, type);
	280	return -EINVAL;
	281	}
	282
	283	if (type & IRQ_TYPE_EDGE_FALLING)
	284	chip->irq_trig_fall \|= mask;
	285	else
	286	chip->irq_trig_fall &= ~mask;
	287
	288	if (type & IRQ_TYPE_EDGE_RISING)
	289	chip->irq_trig_raise \|= mask;
	290	else
	291	chip->irq_trig_raise &= ~mask;
	292
a2cb9aeb	293	return 0;
89ea8bbe MZ	294	}
	295
	296	static struct irq_chip pca953x_irq_chip = {
	297	.name = "pca953x",
	298	.mask = pca953x_irq_mask,
	299	.unmask = pca953x_irq_unmask,
	300	.bus_lock = pca953x_irq_bus_lock,
	301	.bus_sync_unlock = pca953x_irq_bus_sync_unlock,
	302	.set_type = pca953x_irq_set_type,
	303	};
	304
	305	static uint16_t pca953x_irq_pending(struct pca953x_chip *chip)
	306	{
	307	uint16_t cur_stat;
	308	uint16_t old_stat;
	309	uint16_t pending;
	310	uint16_t trigger;
	311	int ret;
	312
	313	ret = pca953x_read_reg(chip, PCA953X_INPUT, &cur_stat);
	314	if (ret)
	315	return 0;
	316
	317	/* Remove output pins from the equation */
	318	cur_stat &= chip->reg_direction;
	319
	320	old_stat = chip->irq_stat;
	321	trigger = (cur_stat ^ old_stat) & chip->irq_mask;
	322
	323	if (!trigger)
	324	return 0;
	325
	326	chip->irq_stat = cur_stat;
	327
	328	pending = (old_stat & chip->irq_trig_fall) \|
	329	(cur_stat & chip->irq_trig_raise);
	330	pending &= trigger;
	331
	332	return pending;
	333	}
	334
	335	static irqreturn_t pca953x_irq_handler(int irq, void *devid)
	336	{
	337	struct pca953x_chip *chip = devid;
	338	uint16_t pending;
	339	uint16_t level;
	340
	341	pending = pca953x_irq_pending(chip);
	342
	343	if (!pending)
	344	return IRQ_HANDLED;
	345
	346	do {
	347	level = __ffs(pending);
8a233f01	348	generic_handle_irq(level + chip->irq_base);
89ea8bbe MZ	349
	350	pending &= ~(1 << level);
	351	} while (pending);
	352
	353	return IRQ_HANDLED;
	354	}
	355
	356	static int pca953x_irq_setup(struct pca953x_chip *chip,
	357	const struct i2c_device_id *id)
	358	{
	359	struct i2c_client *client = chip->client;
	360	struct pca953x_platform_data *pdata = client->dev.platform_data;
	361	int ret;
	362
8a233f01 AD	363	if (pdata->irq_base != -1
8a233f01 AD	364	&& (id->driver_data & PCA953X_INT)) {
89ea8bbe MZ	365	int lvl;
	366
	367	ret = pca953x_read_reg(chip, PCA953X_INPUT,
	368	&chip->irq_stat);
	369	if (ret)
	370	goto out_failed;
	371
	372	/*
	373	* There is no way to know which GPIO line generated the
	374	* interrupt. We have to rely on the previous read for
	375	* this purpose.
	376	*/
	377	chip->irq_stat &= chip->reg_direction;
	378	chip->irq_base = pdata->irq_base;
	379	mutex_init(&chip->irq_lock);
	380
	381	for (lvl = 0; lvl < chip->gpio_chip.ngpio; lvl++) {
	382	int irq = lvl + chip->irq_base;
	383
	384	set_irq_chip_data(irq, chip);
	385	set_irq_chip_and_handler(irq, &pca953x_irq_chip,
	386	handle_edge_irq);
89ea8bbe MZ	387	#ifdef CONFIG_ARM
	388	set_irq_flags(irq, IRQF_VALID);
	389	#else
	390	set_irq_noprobe(irq);
	391	#endif
	392	}
	393
	394	ret = request_threaded_irq(client->irq,
	395	NULL,
	396	pca953x_irq_handler,
8a233f01	397	IRQF_TRIGGER_RISING \|
89ea8bbe MZ	398	IRQF_TRIGGER_FALLING \| IRQF_ONESHOT,
	399	dev_name(&client->dev), chip);
	400	if (ret) {
	401	dev_err(&client->dev, "failed to request irq %d\n",
	402	client->irq);
	403	goto out_failed;
	404	}
	405
	406	chip->gpio_chip.to_irq = pca953x_gpio_to_irq;
	407	}
	408
	409	return 0;
	410
	411	out_failed:
8a233f01	412	chip->irq_base = -1;
89ea8bbe MZ	413	return ret;
	414	}
	415
	416	static void pca953x_irq_teardown(struct pca953x_chip *chip)
	417	{
8a233f01	418	if (chip->irq_base != -1)
89ea8bbe MZ	419	free_irq(chip->client->irq, chip);
	420	}
	421	#else /* CONFIG_GPIO_PCA953X_IRQ */
	422	static int pca953x_irq_setup(struct pca953x_chip *chip,
	423	const struct i2c_device_id *id)
	424	{
	425	struct i2c_client *client = chip->client;
	426	struct pca953x_platform_data *pdata = client->dev.platform_data;
	427
8a233f01	428	if (pdata->irq_base != -1 && (id->driver_data & PCA953X_INT))
89ea8bbe MZ	429	dev_warn(&client->dev, "interrupt support not compiled in\n");
	430
	431	return 0;
	432	}
	433
	434	static void pca953x_irq_teardown(struct pca953x_chip *chip)
	435	{
	436	}
	437	#endif
	438
1965d303 NC	439	/*
	440	* Handlers for alternative sources of platform_data
	441	*/
	442	#ifdef CONFIG_OF_GPIO
	443	/*
	444	* Translate OpenFirmware node properties into platform_data
	445	*/
	446	static struct pca953x_platform_data *
	447	pca953x_get_alt_pdata(struct i2c_client *client)
	448	{
	449	struct pca953x_platform_data *pdata;
	450	struct device_node *node;
	451	const uint16_t *val;
	452
61c7a080	453	node = client->dev.of_node;
1965d303 NC	454	if (node == NULL)
	455	return NULL;
	456
	457	pdata = kzalloc(sizeof(struct pca953x_platform_data), GFP_KERNEL);
	458	if (pdata == NULL) {
	459	dev_err(&client->dev, "Unable to allocate platform_data\n");
	460	return NULL;
	461	}
	462
	463	pdata->gpio_base = -1;
	464	val = of_get_property(node, "linux,gpio-base", NULL);
	465	if (val) {
	466	if (*val < 0)
	467	dev_warn(&client->dev,
	468	"invalid gpio-base in device tree\n");
	469	else
	470	pdata->gpio_base = *val;
	471	}
	472
	473	val = of_get_property(node, "polarity", NULL);
	474	if (val)
	475	pdata->invert = *val;
	476
	477	return pdata;
	478	}
	479	#else
	480	static struct pca953x_platform_data *
	481	pca953x_get_alt_pdata(struct i2c_client *client)
	482	{
	483	return NULL;
	484	}
	485	#endif
	486
d2653e92	487	static int __devinit pca953x_probe(struct i2c_client *client,
3760f736	488	const struct i2c_device_id *id)
9e60fdcf	489	{
f3dc3630 GL	490	struct pca953x_platform_data *pdata;
f3dc3630 GL	491	struct pca953x_chip *chip;
f39e5781	492	int ret;
9e60fdcf	493
1965d303 NC	494	chip = kzalloc(sizeof(struct pca953x_chip), GFP_KERNEL);
	495	if (chip == NULL)
	496	return -ENOMEM;
	497
9e60fdcf	498	pdata = client->dev.platform_data;
a342d215	499	if (pdata == NULL) {
1965d303 NC	500	pdata = pca953x_get_alt_pdata(client);
	501	/*
	502	* Unlike normal platform_data, this is allocated
	503	* dynamically and must be freed in the driver
	504	*/
	505	chip->dyn_pdata = pdata;
a342d215	506	}
9e60fdcf	507
1965d303 NC	508	if (pdata == NULL) {
	509	dev_dbg(&client->dev, "no platform data\n");
	510	ret = -EINVAL;
	511	goto out_failed;
	512	}
9e60fdcf	513
	514	chip->client = client;
	515
	516	chip->gpio_start = pdata->gpio_base;
	517
77906a54 DS	518	chip->names = pdata->names;
77906a54 DS	519
9e60fdcf	520	/* initialize cached registers from their original values.
	521	* we can't share this chip with another i2c master.
	522	*/
89ea8bbe	523	pca953x_setup_gpio(chip, id->driver_data & PCA953X_GPIOS);
f5e8ff48	524
f3dc3630	525	ret = pca953x_read_reg(chip, PCA953X_OUTPUT, &chip->reg_output);
9e60fdcf	526	if (ret)
	527	goto out_failed;
	528
f3dc3630	529	ret = pca953x_read_reg(chip, PCA953X_DIRECTION, &chip->reg_direction);
9e60fdcf	530	if (ret)
	531	goto out_failed;
	532
	533	/* set platform specific polarity inversion */
f3dc3630	534	ret = pca953x_write_reg(chip, PCA953X_INVERT, pdata->invert);
9e60fdcf	535	if (ret)
	536	goto out_failed;
	537
89ea8bbe MZ	538	ret = pca953x_irq_setup(chip, id);
	539	if (ret)
	540	goto out_failed;
f5e8ff48 GL	541
f5e8ff48 GL	542	ret = gpiochip_add(&chip->gpio_chip);
9e60fdcf	543	if (ret)
	544	goto out_failed;
	545
	546	if (pdata->setup) {
	547	ret = pdata->setup(client, chip->gpio_chip.base,
	548	chip->gpio_chip.ngpio, pdata->context);
	549	if (ret < 0)
	550	dev_warn(&client->dev, "setup failed, %d\n", ret);
	551	}
	552
	553	i2c_set_clientdata(client, chip);
	554	return 0;
	555
	556	out_failed:
89ea8bbe	557	pca953x_irq_teardown(chip);
1965d303	558	kfree(chip->dyn_pdata);
9e60fdcf	559	kfree(chip);
	560	return ret;
	561	}
	562
f3dc3630	563	static int pca953x_remove(struct i2c_client *client)
9e60fdcf	564	{
f3dc3630 GL	565	struct pca953x_platform_data *pdata = client->dev.platform_data;
f3dc3630 GL	566	struct pca953x_chip *chip = i2c_get_clientdata(client);
9e60fdcf	567	int ret = 0;
	568
	569	if (pdata->teardown) {
	570	ret = pdata->teardown(client, chip->gpio_chip.base,
	571	chip->gpio_chip.ngpio, pdata->context);
	572	if (ret < 0) {
	573	dev_err(&client->dev, "%s failed, %d\n",
	574	"teardown", ret);
	575	return ret;
	576	}
	577	}
	578
	579	ret = gpiochip_remove(&chip->gpio_chip);
	580	if (ret) {
	581	dev_err(&client->dev, "%s failed, %d\n",
	582	"gpiochip_remove()", ret);
	583	return ret;
	584	}
	585
89ea8bbe	586	pca953x_irq_teardown(chip);
1965d303	587	kfree(chip->dyn_pdata);
9e60fdcf	588	kfree(chip);
	589	return 0;
	590	}
	591
f3dc3630	592	static struct i2c_driver pca953x_driver = {
9e60fdcf	593	.driver = {
f3dc3630	594	.name = "pca953x",
9e60fdcf	595	},
f3dc3630 GL	596	.probe = pca953x_probe,
f3dc3630 GL	597	.remove = pca953x_remove,
3760f736	598	.id_table = pca953x_id,
9e60fdcf	599	};
9e60fdcf	600
f3dc3630	601	static int __init pca953x_init(void)
9e60fdcf	602	{
f3dc3630	603	return i2c_add_driver(&pca953x_driver);
9e60fdcf	604	}
2f8d1197 DB	605	/* register after i2c postcore initcall and before
	606	* subsys initcalls that may rely on these GPIOs
	607	*/
	608	subsys_initcall(pca953x_init);
9e60fdcf	609
f3dc3630	610	static void __exit pca953x_exit(void)
9e60fdcf	611	{
f3dc3630	612	i2c_del_driver(&pca953x_driver);
9e60fdcf	613	}
f3dc3630	614	module_exit(pca953x_exit);
9e60fdcf	615
9e60fdcf	616	MODULE_AUTHOR("eric miao <eric.miao@marvell.com>");
f3dc3630	617	MODULE_DESCRIPTION("GPIO expander driver for PCA953x");
9e60fdcf	618	MODULE_LICENSE("GPL");