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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Copyright (C) 2015-2023 Texas Instruments Incorporated - https://www.ti.com/4 * Andrew Davis <afd@ti.com>5 */6 7#include <linux/gpio/driver.h>8#include <linux/i2c.h>9#include <linux/module.h>10#include <linux/mutex.h>11 12#define TPIC2810_WS_COMMAND 0x4413 14/**15 * struct tpic2810 - GPIO driver data16 * @chip: GPIO controller chip17 * @client: I2C device pointer18 * @buffer: Buffer for device register19 * @lock: Protects write sequences20 */21struct tpic2810 {22 struct gpio_chip chip;23 struct i2c_client *client;24 u8 buffer;25 struct mutex lock;26};27 28static void tpic2810_set(struct gpio_chip *chip, unsigned offset, int value);29 30static int tpic2810_get_direction(struct gpio_chip *chip,31 unsigned offset)32{33 /* This device always output */34 return GPIO_LINE_DIRECTION_OUT;35}36 37static int tpic2810_direction_input(struct gpio_chip *chip,38 unsigned offset)39{40 /* This device is output only */41 return -EINVAL;42}43 44static int tpic2810_direction_output(struct gpio_chip *chip,45 unsigned offset, int value)46{47 /* This device always output */48 tpic2810_set(chip, offset, value);49 return 0;50}51 52static void tpic2810_set_mask_bits(struct gpio_chip *chip, u8 mask, u8 bits)53{54 struct tpic2810 *gpio = gpiochip_get_data(chip);55 u8 buffer;56 int err;57 58 mutex_lock(&gpio->lock);59 60 buffer = gpio->buffer & ~mask;61 buffer |= (mask & bits);62 63 err = i2c_smbus_write_byte_data(gpio->client, TPIC2810_WS_COMMAND,64 buffer);65 if (!err)66 gpio->buffer = buffer;67 68 mutex_unlock(&gpio->lock);69}70 71static void tpic2810_set(struct gpio_chip *chip, unsigned offset, int value)72{73 tpic2810_set_mask_bits(chip, BIT(offset), value ? BIT(offset) : 0);74}75 76static void tpic2810_set_multiple(struct gpio_chip *chip, unsigned long *mask,77 unsigned long *bits)78{79 tpic2810_set_mask_bits(chip, *mask, *bits);80}81 82static const struct gpio_chip template_chip = {83 .label = "tpic2810",84 .owner = THIS_MODULE,85 .get_direction = tpic2810_get_direction,86 .direction_input = tpic2810_direction_input,87 .direction_output = tpic2810_direction_output,88 .set = tpic2810_set,89 .set_multiple = tpic2810_set_multiple,90 .base = -1,91 .ngpio = 8,92 .can_sleep = true,93};94 95static const struct of_device_id tpic2810_of_match_table[] = {96 { .compatible = "ti,tpic2810" },97 { /* sentinel */ }98};99MODULE_DEVICE_TABLE(of, tpic2810_of_match_table);100 101static int tpic2810_probe(struct i2c_client *client)102{103 struct tpic2810 *gpio;104 105 gpio = devm_kzalloc(&client->dev, sizeof(*gpio), GFP_KERNEL);106 if (!gpio)107 return -ENOMEM;108 109 gpio->chip = template_chip;110 gpio->chip.parent = &client->dev;111 112 gpio->client = client;113 114 mutex_init(&gpio->lock);115 116 return devm_gpiochip_add_data(&client->dev, &gpio->chip, gpio);117}118 119static const struct i2c_device_id tpic2810_id_table[] = {120 { "tpic2810", },121 { /* sentinel */ }122};123MODULE_DEVICE_TABLE(i2c, tpic2810_id_table);124 125static struct i2c_driver tpic2810_driver = {126 .driver = {127 .name = "tpic2810",128 .of_match_table = tpic2810_of_match_table,129 },130 .probe = tpic2810_probe,131 .id_table = tpic2810_id_table,132};133module_i2c_driver(tpic2810_driver);134 135MODULE_AUTHOR("Andrew Davis <afd@ti.com>");136MODULE_DESCRIPTION("TPIC2810 8-Bit LED Driver GPIO Driver");137MODULE_LICENSE("GPL v2");138