[linux-2.6-block.git] / drivers / gpio / gpio-pca9570.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Driver for PCA9570 I2C GPO expander
 *
 * Copyright (C) 2020 Sungbo Eo <mans0n@gorani.run>
 *
 * Based on gpio-tpic2810.c
 * Copyright (C) 2015 Texas Instruments Incorporated - http://www.ti.com/
 *	Andrew F. Davis <afd@ti.com>
 */

#include <linux/gpio/driver.h>
#include <linux/i2c.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/property.h>

#define SLG7XL45106_GPO_REG	0xDB

/**
 * struct pca9570_chip_data - GPIO platformdata
 * @ngpio: no of gpios
 * @command: Command to be sent
 */
struct pca9570_chip_data {
	u16 ngpio;
	u32 command;
};

/**
 * struct pca9570 - GPIO driver data
 * @chip: GPIO controller chip
 * @chip_data: GPIO controller platform data
 * @lock: Protects write sequences
 * @out: Buffer for device register
 */
struct pca9570 {
	struct gpio_chip chip;
	const struct pca9570_chip_data *chip_data;
	struct mutex lock;
	u8 out;
};

static int pca9570_read(struct pca9570 *gpio, u8 *value)
{
	struct i2c_client *client = to_i2c_client(gpio->chip.parent);
	int ret;

	if (gpio->chip_data->command != 0)
		ret = i2c_smbus_read_byte_data(client, gpio->chip_data->command);
	else
		ret = i2c_smbus_read_byte(client);

	if (ret < 0)
		return ret;

	*value = ret;
	return 0;
}

static int pca9570_write(struct pca9570 *gpio, u8 value)
{
	struct i2c_client *client = to_i2c_client(gpio->chip.parent);

	if (gpio->chip_data->command != 0)
		return i2c_smbus_write_byte_data(client, gpio->chip_data->command, value);

	return i2c_smbus_write_byte(client, value);
}

static int pca9570_get_direction(struct gpio_chip *chip,
				 unsigned offset)
{
	/* This device always output */
	return GPIO_LINE_DIRECTION_OUT;
}

static int pca9570_get(struct gpio_chip *chip, unsigned offset)
{
	struct pca9570 *gpio = gpiochip_get_data(chip);
	u8 buffer;
	int ret;

	ret = pca9570_read(gpio, &buffer);
	if (ret)
		return ret;

	return !!(buffer & BIT(offset));
}

static void pca9570_set(struct gpio_chip *chip, unsigned offset, int value)
{
	struct pca9570 *gpio = gpiochip_get_data(chip);
	u8 buffer;
	int ret;

	mutex_lock(&gpio->lock);

	buffer = gpio->out;
	if (value)
		buffer |= BIT(offset);
	else
		buffer &= ~BIT(offset);

	ret = pca9570_write(gpio, buffer);
	if (ret)
		goto out;

	gpio->out = buffer;

out:
	mutex_unlock(&gpio->lock);
}

static int pca9570_probe(struct i2c_client *client)
{
	struct pca9570 *gpio;

	gpio = devm_kzalloc(&client->dev, sizeof(*gpio), GFP_KERNEL);
	if (!gpio)
		return -ENOMEM;

	gpio->chip.label = client->name;
	gpio->chip.parent = &client->dev;
	gpio->chip.owner = THIS_MODULE;
	gpio->chip.get_direction = pca9570_get_direction;
	gpio->chip.get = pca9570_get;
	gpio->chip.set = pca9570_set;
	gpio->chip.base = -1;
	gpio->chip_data = device_get_match_data(&client->dev);
	gpio->chip.ngpio = gpio->chip_data->ngpio;
	gpio->chip.can_sleep = true;

	mutex_init(&gpio->lock);

	/* Read the current output level */
	pca9570_read(gpio, &gpio->out);

	i2c_set_clientdata(client, gpio);

	return devm_gpiochip_add_data(&client->dev, &gpio->chip, gpio);
}

static const struct pca9570_chip_data pca9570_gpio = {
	.ngpio = 4,
};

static const struct pca9570_chip_data pca9571_gpio = {
	.ngpio = 8,
};

static const struct pca9570_chip_data slg7xl45106_gpio = {
	.ngpio = 8,
	.command = SLG7XL45106_GPO_REG,
};

static const struct i2c_device_id pca9570_id_table[] = {
	{ "pca9570", (kernel_ulong_t)&pca9570_gpio},
	{ "pca9571", (kernel_ulong_t)&pca9571_gpio },
	{ "slg7xl45106", (kernel_ulong_t)&slg7xl45106_gpio },
	{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(i2c, pca9570_id_table);

static const struct of_device_id pca9570_of_match_table[] = {
	{ .compatible = "dlg,slg7xl45106", .data = &slg7xl45106_gpio},
	{ .compatible = "nxp,pca9570", .data = &pca9570_gpio },
	{ .compatible = "nxp,pca9571", .data = &pca9571_gpio },
	{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, pca9570_of_match_table);

static struct i2c_driver pca9570_driver = {
	.driver = {
		.name = "pca9570",
		.of_match_table = pca9570_of_match_table,
	},
	.probe = pca9570_probe,
	.id_table = pca9570_id_table,
};
module_i2c_driver(pca9570_driver);

MODULE_AUTHOR("Sungbo Eo <mans0n@gorani.run>");
MODULE_DESCRIPTION("GPIO expander driver for PCA9570");
MODULE_LICENSE("GPL v2");
Commit	Line	Data
16d44b60 SE	1	// SPDX-License-Identifier: GPL-2.0-only
	2	/*
	3	* Driver for PCA9570 I2C GPO expander
	4	*
	5	* Copyright (C) 2020 Sungbo Eo <mans0n@gorani.run>
	6	*
	7	* Based on gpio-tpic2810.c
	8	* Copyright (C) 2015 Texas Instruments Incorporated - http://www.ti.com/
	9	* Andrew F. Davis <afd@ti.com>
	10	*/
	11
	12	#include <linux/gpio/driver.h>
	13	#include <linux/i2c.h>
	14	#include <linux/module.h>
	15	#include <linux/mutex.h>
	16	#include <linux/property.h>
	17
fbb19fe1 SD	18	#define SLG7XL45106_GPO_REG 0xDB
fbb19fe1 SD	19
b8a34582	20	/**
a3f7c1d6	21	* struct pca9570_chip_data - GPIO platformdata
b8a34582 SD	22	* @ngpio: no of gpios
	23	* @command: Command to be sent
	24	*/
a3f7c1d6	25	struct pca9570_chip_data {
b8a34582 SD	26	u16 ngpio;
	27	u32 command;
	28	};
	29
16d44b60 SE	30	/**
	31	* struct pca9570 - GPIO driver data
	32	* @chip: GPIO controller chip
82dbbfdf	33	* @chip_data: GPIO controller platform data
16d44b60 SE	34	* @lock: Protects write sequences
	35	* @out: Buffer for device register
	36	*/
	37	struct pca9570 {
	38	struct gpio_chip chip;
a3f7c1d6	39	const struct pca9570_chip_data *chip_data;
16d44b60 SE	40	struct mutex lock;
	41	u8 out;
	42	};
	43
	44	static int pca9570_read(struct pca9570 gpio, u8 value)
	45	{
	46	struct i2c_client *client = to_i2c_client(gpio->chip.parent);
	47	int ret;
	48
a3f7c1d6 BG	49	if (gpio->chip_data->command != 0)
a3f7c1d6 BG	50	ret = i2c_smbus_read_byte_data(client, gpio->chip_data->command);
fbb19fe1 SD	51	else
	52	ret = i2c_smbus_read_byte(client);
	53
16d44b60 SE	54	if (ret < 0)
	55	return ret;
	56
	57	*value = ret;
	58	return 0;
	59	}
	60
	61	static int pca9570_write(struct pca9570 *gpio, u8 value)
	62	{
	63	struct i2c_client *client = to_i2c_client(gpio->chip.parent);
	64
a3f7c1d6 BG	65	if (gpio->chip_data->command != 0)
a3f7c1d6 BG	66	return i2c_smbus_write_byte_data(client, gpio->chip_data->command, value);
fbb19fe1	67
16d44b60 SE	68	return i2c_smbus_write_byte(client, value);
	69	}
	70
	71	static int pca9570_get_direction(struct gpio_chip *chip,
	72	unsigned offset)
	73	{
	74	/* This device always output */
	75	return GPIO_LINE_DIRECTION_OUT;
	76	}
	77
	78	static int pca9570_get(struct gpio_chip *chip, unsigned offset)
	79	{
	80	struct pca9570 *gpio = gpiochip_get_data(chip);
	81	u8 buffer;
	82	int ret;
	83
	84	ret = pca9570_read(gpio, &buffer);
	85	if (ret)
	86	return ret;
	87
	88	return !!(buffer & BIT(offset));
	89	}
	90
	91	static void pca9570_set(struct gpio_chip *chip, unsigned offset, int value)
	92	{
	93	struct pca9570 *gpio = gpiochip_get_data(chip);
	94	u8 buffer;
	95	int ret;
	96
	97	mutex_lock(&gpio->lock);
	98
	99	buffer = gpio->out;
	100	if (value)
	101	buffer \|= BIT(offset);
	102	else
	103	buffer &= ~BIT(offset);
	104
	105	ret = pca9570_write(gpio, buffer);
	106	if (ret)
	107	goto out;
	108
	109	gpio->out = buffer;
	110
	111	out:
	112	mutex_unlock(&gpio->lock);
	113	}
	114
	115	static int pca9570_probe(struct i2c_client *client)
	116	{
	117	struct pca9570 *gpio;
	118
	119	gpio = devm_kzalloc(&client->dev, sizeof(*gpio), GFP_KERNEL);
	120	if (!gpio)
	121	return -ENOMEM;
	122
	123	gpio->chip.label = client->name;
	124	gpio->chip.parent = &client->dev;
	125	gpio->chip.owner = THIS_MODULE;
	126	gpio->chip.get_direction = pca9570_get_direction;
	127	gpio->chip.get = pca9570_get;
	128	gpio->chip.set = pca9570_set;
	129	gpio->chip.base = -1;
a3f7c1d6 BG	130	gpio->chip_data = device_get_match_data(&client->dev);
a3f7c1d6 BG	131	gpio->chip.ngpio = gpio->chip_data->ngpio;
16d44b60 SE	132	gpio->chip.can_sleep = true;
	133
	134	mutex_init(&gpio->lock);
	135
	136	/* Read the current output level */
	137	pca9570_read(gpio, &gpio->out);
	138
	139	i2c_set_clientdata(client, gpio);
	140
	141	return devm_gpiochip_add_data(&client->dev, &gpio->chip, gpio);
	142	}
	143
a3f7c1d6	144	static const struct pca9570_chip_data pca9570_gpio = {
b8a34582 SD	145	.ngpio = 4,
	146	};
	147
a3f7c1d6	148	static const struct pca9570_chip_data pca9571_gpio = {
b8a34582 SD	149	.ngpio = 8,
	150	};
	151
a3f7c1d6	152	static const struct pca9570_chip_data slg7xl45106_gpio = {
fbb19fe1 SD	153	.ngpio = 8,
	154	.command = SLG7XL45106_GPO_REG,
	155	};
	156
16d44b60	157	static const struct i2c_device_id pca9570_id_table[] = {
b8a34582 SD	158	{ "pca9570", (kernel_ulong_t)&pca9570_gpio},
b8a34582 SD	159	{ "pca9571", (kernel_ulong_t)&pca9571_gpio },
fbb19fe1	160	{ "slg7xl45106", (kernel_ulong_t)&slg7xl45106_gpio },
16d44b60 SE	161	{ /* sentinel */ }
	162	};
	163	MODULE_DEVICE_TABLE(i2c, pca9570_id_table);
	164
	165	static const struct of_device_id pca9570_of_match_table[] = {
fbb19fe1	166	{ .compatible = "dlg,slg7xl45106", .data = &slg7xl45106_gpio},
b8a34582 SD	167	{ .compatible = "nxp,pca9570", .data = &pca9570_gpio },
b8a34582 SD	168	{ .compatible = "nxp,pca9571", .data = &pca9571_gpio },
16d44b60 SE	169	{ /* sentinel */ }
	170	};
	171	MODULE_DEVICE_TABLE(of, pca9570_of_match_table);
	172
	173	static struct i2c_driver pca9570_driver = {
	174	.driver = {
	175	.name = "pca9570",
	176	.of_match_table = pca9570_of_match_table,
	177	},
b41cabb7	178	.probe = pca9570_probe,
16d44b60 SE	179	.id_table = pca9570_id_table,
	180	};
	181	module_i2c_driver(pca9570_driver);
	182
	183	MODULE_AUTHOR("Sungbo Eo <mans0n@gorani.run>");
	184	MODULE_DESCRIPTION("GPIO expander driver for PCA9570");
	185	MODULE_LICENSE("GPL v2");