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 | |
18 | static const struct regmap_config ds4520_regmap_config = { |
19 | .reg_bits = 8, |
20 | .val_bits = 8, |
21 | }; |
22 | |
23 | static 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 ngpio; |
29 | u32 base; |
30 | int ret; |
31 | |
32 | ret = device_property_read_u32(dev, propname: "reg" , val: &base); |
33 | if (ret) |
34 | return dev_err_probe(dev, err: ret, fmt: "Missing 'reg' property.\n" ); |
35 | |
36 | ret = device_property_read_u32(dev, propname: "ngpios" , val: &ngpio); |
37 | if (ret) |
38 | return dev_err_probe(dev, err: ret, fmt: "Missing 'ngpios' property.\n" ); |
39 | |
40 | regmap = devm_regmap_init_i2c(client, &ds4520_regmap_config); |
41 | if (IS_ERR(ptr: regmap)) |
42 | return dev_err_probe(dev, err: PTR_ERR(ptr: regmap), |
43 | fmt: "Failed to allocate register map\n" ); |
44 | |
45 | config.regmap = regmap; |
46 | config.parent = dev; |
47 | config.ngpio = ngpio; |
48 | |
49 | config.reg_dat_base = base + DS4520_IO_STATUS0; |
50 | config.reg_set_base = base + DS4520_PULLUP0; |
51 | config.reg_dir_out_base = base + DS4520_IO_CONTROL0; |
52 | |
53 | return PTR_ERR_OR_ZERO(ptr: devm_gpio_regmap_register(dev, config: &config)); |
54 | } |
55 | |
56 | static const struct of_device_id ds4520_gpio_of_match_table[] = { |
57 | { .compatible = "adi,ds4520-gpio" }, |
58 | { } |
59 | }; |
60 | MODULE_DEVICE_TABLE(of, ds4520_gpio_of_match_table); |
61 | |
62 | static const struct i2c_device_id ds4520_gpio_id_table[] = { |
63 | { "ds4520-gpio" }, |
64 | { } |
65 | }; |
66 | MODULE_DEVICE_TABLE(i2c, ds4520_gpio_id_table); |
67 | |
68 | static struct i2c_driver ds4520_gpio_driver = { |
69 | .driver = { |
70 | .name = "ds4520-gpio" , |
71 | .of_match_table = ds4520_gpio_of_match_table, |
72 | }, |
73 | .probe = ds4520_gpio_probe, |
74 | .id_table = ds4520_gpio_id_table, |
75 | }; |
76 | module_i2c_driver(ds4520_gpio_driver); |
77 | |
78 | MODULE_DESCRIPTION("DS4520 I/O Expander" ); |
79 | MODULE_AUTHOR("Okan Sahin <okan.sahin@analog.com>" ); |
80 | MODULE_LICENSE("GPL" ); |
81 | |