[deliverable/linux.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/i2c.h>
#include <linux/i2c/pca953x.h>
#ifdef CONFIG_OF_GPIO
#include <linux/of_platform.h>
#include <linux/of_gpio.h>
#endif

#include <asm/gpio.h>

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

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

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

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

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

/*
 * 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 = dev_archdata_get_node(&client->dev.archdata);
	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);

	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 = 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:
	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;
	}

	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
	1	/*
	2	* pca953x.c - 4/8/16 bit I/O ports
	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>
	16	#include <linux/i2c.h>
	17	#include <linux/i2c/pca953x.h>
	18	#ifdef CONFIG_OF_GPIO
	19	#include <linux/of_platform.h>
	20	#include <linux/of_gpio.h>
	21	#endif
	22
	23	#include <asm/gpio.h>
	24
	25	#define PCA953X_INPUT 0
	26	#define PCA953X_OUTPUT 1
	27	#define PCA953X_INVERT 2
	28	#define PCA953X_DIRECTION 3
	29
	30	static const struct i2c_device_id pca953x_id[] = {
	31	{ "pca9534", 8, },
	32	{ "pca9535", 16, },
	33	{ "pca9536", 4, },
	34	{ "pca9537", 4, },
	35	{ "pca9538", 8, },
	36	{ "pca9539", 16, },
	37	{ "pca9554", 8, },
	38	{ "pca9555", 16, },
	39	{ "pca9556", 8, },
	40	{ "pca9557", 8, },
	41
	42	{ "max7310", 8, },
	43	{ "max7315", 8, },
	44	{ "pca6107", 8, },
	45	{ "tca6408", 8, },
	46	{ "tca6416", 16, },
	47	/* NYET: { "tca6424", 24, }, */
	48	{ }
	49	};
	50	MODULE_DEVICE_TABLE(i2c, pca953x_id);
	51
	52	struct pca953x_chip {
	53	unsigned gpio_start;
	54	uint16_t reg_output;
	55	uint16_t reg_direction;
	56
	57	struct i2c_client *client;
	58	struct pca953x_platform_data *dyn_pdata;
	59	struct gpio_chip gpio_chip;
	60	char **names;
	61	};
	62
	63	static int pca953x_write_reg(struct pca953x_chip *chip, int reg, uint16_t val)
	64	{
	65	int ret;
	66
	67	if (chip->gpio_chip.ngpio <= 8)
	68	ret = i2c_smbus_write_byte_data(chip->client, reg, val);
	69	else
	70	ret = i2c_smbus_write_word_data(chip->client, reg << 1, val);
	71
	72	if (ret < 0) {
	73	dev_err(&chip->client->dev, "failed writing register\n");
	74	return ret;
	75	}
	76
	77	return 0;
	78	}
	79
	80	static int pca953x_read_reg(struct pca953x_chip chip, int reg, uint16_t val)
	81	{
	82	int ret;
	83
	84	if (chip->gpio_chip.ngpio <= 8)
	85	ret = i2c_smbus_read_byte_data(chip->client, reg);
	86	else
	87	ret = i2c_smbus_read_word_data(chip->client, reg << 1);
	88
	89	if (ret < 0) {
	90	dev_err(&chip->client->dev, "failed reading register\n");
	91	return ret;
	92	}
	93
	94	*val = (uint16_t)ret;
	95	return 0;
	96	}
	97
	98	static int pca953x_gpio_direction_input(struct gpio_chip *gc, unsigned off)
	99	{
	100	struct pca953x_chip *chip;
	101	uint16_t reg_val;
	102	int ret;
	103
	104	chip = container_of(gc, struct pca953x_chip, gpio_chip);
	105
	106	reg_val = chip->reg_direction \| (1u << off);
	107	ret = pca953x_write_reg(chip, PCA953X_DIRECTION, reg_val);
	108	if (ret)
	109	return ret;
	110
	111	chip->reg_direction = reg_val;
	112	return 0;
	113	}
	114
	115	static int pca953x_gpio_direction_output(struct gpio_chip *gc,
	116	unsigned off, int val)
	117	{
	118	struct pca953x_chip *chip;
	119	uint16_t reg_val;
	120	int ret;
	121
	122	chip = container_of(gc, struct pca953x_chip, gpio_chip);
	123
	124	/* set output level */
	125	if (val)
	126	reg_val = chip->reg_output \| (1u << off);
	127	else
	128	reg_val = chip->reg_output & ~(1u << off);
	129
	130	ret = pca953x_write_reg(chip, PCA953X_OUTPUT, reg_val);
	131	if (ret)
	132	return ret;
	133
	134	chip->reg_output = reg_val;
	135
	136	/* then direction */
	137	reg_val = chip->reg_direction & ~(1u << off);
	138	ret = pca953x_write_reg(chip, PCA953X_DIRECTION, reg_val);
	139	if (ret)
	140	return ret;
	141
	142	chip->reg_direction = reg_val;
	143	return 0;
	144	}
	145
	146	static int pca953x_gpio_get_value(struct gpio_chip *gc, unsigned off)
	147	{
	148	struct pca953x_chip *chip;
	149	uint16_t reg_val;
	150	int ret;
	151
	152	chip = container_of(gc, struct pca953x_chip, gpio_chip);
	153
	154	ret = pca953x_read_reg(chip, PCA953X_INPUT, &reg_val);
	155	if (ret < 0) {
	156	/* NOTE: diagnostic already emitted; that's all we should
	157	* do unless gpio_*_value_cansleep() calls become different
	158	* from their nonsleeping siblings (and report faults).
	159	*/
	160	return 0;
	161	}
	162
	163	return (reg_val & (1u << off)) ? 1 : 0;
	164	}
	165
	166	static void pca953x_gpio_set_value(struct gpio_chip *gc, unsigned off, int val)
	167	{
	168	struct pca953x_chip *chip;
	169	uint16_t reg_val;
	170	int ret;
	171
	172	chip = container_of(gc, struct pca953x_chip, gpio_chip);
	173
	174	if (val)
	175	reg_val = chip->reg_output \| (1u << off);
	176	else
	177	reg_val = chip->reg_output & ~(1u << off);
	178
	179	ret = pca953x_write_reg(chip, PCA953X_OUTPUT, reg_val);
	180	if (ret)
	181	return;
	182
	183	chip->reg_output = reg_val;
	184	}
	185
	186	static void pca953x_setup_gpio(struct pca953x_chip *chip, int gpios)
	187	{
	188	struct gpio_chip *gc;
	189
	190	gc = &chip->gpio_chip;
	191
	192	gc->direction_input = pca953x_gpio_direction_input;
	193	gc->direction_output = pca953x_gpio_direction_output;
	194	gc->get = pca953x_gpio_get_value;
	195	gc->set = pca953x_gpio_set_value;
	196	gc->can_sleep = 1;
	197
	198	gc->base = chip->gpio_start;
	199	gc->ngpio = gpios;
	200	gc->label = chip->client->name;
	201	gc->dev = &chip->client->dev;
	202	gc->owner = THIS_MODULE;
	203	gc->names = chip->names;
	204	}
	205
	206	/*
	207	* Handlers for alternative sources of platform_data
	208	*/
	209	#ifdef CONFIG_OF_GPIO
	210	/*
	211	* Translate OpenFirmware node properties into platform_data
	212	*/
	213	static struct pca953x_platform_data *
	214	pca953x_get_alt_pdata(struct i2c_client *client)
	215	{
	216	struct pca953x_platform_data *pdata;
	217	struct device_node *node;
	218	const uint16_t *val;
	219
	220	node = dev_archdata_get_node(&client->dev.archdata);
	221	if (node == NULL)
	222	return NULL;
	223
	224	pdata = kzalloc(sizeof(struct pca953x_platform_data), GFP_KERNEL);
	225	if (pdata == NULL) {
	226	dev_err(&client->dev, "Unable to allocate platform_data\n");
	227	return NULL;
	228	}
	229
	230	pdata->gpio_base = -1;
	231	val = of_get_property(node, "linux,gpio-base", NULL);
	232	if (val) {
	233	if (*val < 0)
	234	dev_warn(&client->dev,
	235	"invalid gpio-base in device tree\n");
	236	else
	237	pdata->gpio_base = *val;
	238	}
	239
	240	val = of_get_property(node, "polarity", NULL);
	241	if (val)
	242	pdata->invert = *val;
	243
	244	return pdata;
	245	}
	246	#else
	247	static struct pca953x_platform_data *
	248	pca953x_get_alt_pdata(struct i2c_client *client)
	249	{
	250	return NULL;
	251	}
	252	#endif
	253
	254	static int __devinit pca953x_probe(struct i2c_client *client,
	255	const struct i2c_device_id *id)
	256	{
	257	struct pca953x_platform_data *pdata;
	258	struct pca953x_chip *chip;
	259	int ret;
	260
	261	chip = kzalloc(sizeof(struct pca953x_chip), GFP_KERNEL);
	262	if (chip == NULL)
	263	return -ENOMEM;
	264
	265	pdata = client->dev.platform_data;
	266	if (pdata == NULL) {
	267	pdata = pca953x_get_alt_pdata(client);
	268	/*
	269	* Unlike normal platform_data, this is allocated
	270	* dynamically and must be freed in the driver
	271	*/
	272	chip->dyn_pdata = pdata;
	273	}
	274
	275	if (pdata == NULL) {
	276	dev_dbg(&client->dev, "no platform data\n");
	277	ret = -EINVAL;
	278	goto out_failed;
	279	}
	280
	281	chip->client = client;
	282
	283	chip->gpio_start = pdata->gpio_base;
	284
	285	chip->names = pdata->names;
	286
	287	/* initialize cached registers from their original values.
	288	* we can't share this chip with another i2c master.
	289	*/
	290	pca953x_setup_gpio(chip, id->driver_data);
	291
	292	ret = pca953x_read_reg(chip, PCA953X_OUTPUT, &chip->reg_output);
	293	if (ret)
	294	goto out_failed;
	295
	296	ret = pca953x_read_reg(chip, PCA953X_DIRECTION, &chip->reg_direction);
	297	if (ret)
	298	goto out_failed;
	299
	300	/* set platform specific polarity inversion */
	301	ret = pca953x_write_reg(chip, PCA953X_INVERT, pdata->invert);
	302	if (ret)
	303	goto out_failed;
	304
	305
	306	ret = gpiochip_add(&chip->gpio_chip);
	307	if (ret)
	308	goto out_failed;
	309
	310	if (pdata->setup) {
	311	ret = pdata->setup(client, chip->gpio_chip.base,
	312	chip->gpio_chip.ngpio, pdata->context);
	313	if (ret < 0)
	314	dev_warn(&client->dev, "setup failed, %d\n", ret);
	315	}
	316
	317	i2c_set_clientdata(client, chip);
	318	return 0;
	319
	320	out_failed:
	321	kfree(chip->dyn_pdata);
	322	kfree(chip);
	323	return ret;
	324	}
	325
	326	static int pca953x_remove(struct i2c_client *client)
	327	{
	328	struct pca953x_platform_data *pdata = client->dev.platform_data;
	329	struct pca953x_chip *chip = i2c_get_clientdata(client);
	330	int ret = 0;
	331
	332	if (pdata->teardown) {
	333	ret = pdata->teardown(client, chip->gpio_chip.base,
	334	chip->gpio_chip.ngpio, pdata->context);
	335	if (ret < 0) {
	336	dev_err(&client->dev, "%s failed, %d\n",
	337	"teardown", ret);
	338	return ret;
	339	}
	340	}
	341
	342	ret = gpiochip_remove(&chip->gpio_chip);
	343	if (ret) {
	344	dev_err(&client->dev, "%s failed, %d\n",
	345	"gpiochip_remove()", ret);
	346	return ret;
	347	}
	348
	349	kfree(chip->dyn_pdata);
	350	kfree(chip);
	351	return 0;
	352	}
	353
	354	static struct i2c_driver pca953x_driver = {
	355	.driver = {
	356	.name = "pca953x",
	357	},
	358	.probe = pca953x_probe,
	359	.remove = pca953x_remove,
	360	.id_table = pca953x_id,
	361	};
	362
	363	static int __init pca953x_init(void)
	364	{
	365	return i2c_add_driver(&pca953x_driver);
	366	}
	367	/* register after i2c postcore initcall and before
	368	* subsys initcalls that may rely on these GPIOs
	369	*/
	370	subsys_initcall(pca953x_init);
	371
	372	static void __exit pca953x_exit(void)
	373	{
	374	i2c_del_driver(&pca953x_driver);
	375	}
	376	module_exit(pca953x_exit);
	377
	378	MODULE_AUTHOR("eric miao <eric.miao@marvell.com>");
	379	MODULE_DESCRIPTION("GPIO expander driver for PCA953x");
	380	MODULE_LICENSE("GPL");