gpio-ds4520.c

 1// SPDX-License-Identifier: GPL-2.0-or-later
 2/*
 3 * Copyright (c) 2023 Analog Devices, Inc.
 4 * Driver for the DS4520 I/O Expander
 5 */
 6
 7#include <linux/device.h>
 8#include <linux/gpio/driver.h>
 9#include <linux/gpio/regmap.h>
10#include <linux/i2c.h>
11#include <linux/property.h>
12#include <linux/regmap.h>
13
14#define DS4520_PULLUP0		0xF0
15#define DS4520_IO_CONTROL0	0xF2
16#define DS4520_IO_STATUS0	0xF8
17
18static const struct regmap_config ds4520_regmap_config = {
19	.reg_bits = 8,
20	.val_bits = 8,
21};
22
23static int ds4520_gpio_probe(struct i2c_client *client)
24{
25	struct gpio_regmap_config config = { };
26	struct device *dev = &client->dev;
27	struct regmap *regmap;
28	u32 base;
29	int ret;
30
31	ret = device_property_read_u32(dev, "reg", &base);
32	if (ret)
33		return dev_err_probe(dev, ret, "Missing 'reg' property.\n");
34
35	regmap = devm_regmap_init_i2c(client, &ds4520_regmap_config);
36	if (IS_ERR(regmap))
37		return dev_err_probe(dev, PTR_ERR(regmap),
38				     "Failed to allocate register map\n");
39
40	config.regmap = regmap;
41	config.parent = dev;
42
43	config.reg_dat_base = base + DS4520_IO_STATUS0;
44	config.reg_set_base = base + DS4520_PULLUP0;
45	config.reg_dir_out_base = base + DS4520_IO_CONTROL0;
46
47	return PTR_ERR_OR_ZERO(devm_gpio_regmap_register(dev, &config));
48}
49
50static const struct of_device_id ds4520_gpio_of_match_table[] = {
51	{ .compatible = "adi,ds4520-gpio" },
52	{ }
53};
54MODULE_DEVICE_TABLE(of, ds4520_gpio_of_match_table);
55
56static const struct i2c_device_id ds4520_gpio_id_table[] = {
57	{ "ds4520-gpio" },
58	{ }
59};
60MODULE_DEVICE_TABLE(i2c, ds4520_gpio_id_table);
61
62static struct i2c_driver ds4520_gpio_driver = {
63	.driver = {
64		.name = "ds4520-gpio",
65		.of_match_table = ds4520_gpio_of_match_table,
66	},
67	.probe = ds4520_gpio_probe,
68	.id_table = ds4520_gpio_id_table,
69};
70module_i2c_driver(ds4520_gpio_driver);
71
72MODULE_DESCRIPTION("DS4520 I/O Expander");
73MODULE_AUTHOR("Okan Sahin <okan.sahin@analog.com>");
74MODULE_LICENSE("GPL");