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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 |
19 | ||
b8a34582 SD |
20 | /** |
21 | * struct pca9570_platform_data - GPIO platformdata | |
22 | * @ngpio: no of gpios | |
23 | * @command: Command to be sent | |
24 | */ | |
25 | struct pca9570_platform_data { | |
26 | u16 ngpio; | |
27 | u32 command; | |
28 | }; | |
29 | ||
16d44b60 SE |
30 | /** |
31 | * struct pca9570 - GPIO driver data | |
32 | * @chip: GPIO controller chip | |
b8a34582 | 33 | * @p_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; | |
b8a34582 | 39 | const struct pca9570_platform_data *p_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 | ||
fbb19fe1 SD |
49 | if (gpio->p_data->command != 0) |
50 | ret = i2c_smbus_read_byte_data(client, gpio->p_data->command); | |
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 | ||
fbb19fe1 SD |
65 | if (gpio->p_data->command != 0) |
66 | return i2c_smbus_write_byte_data(client, gpio->p_data->command, value); | |
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; | |
b8a34582 SD |
130 | gpio->p_data = device_get_match_data(&client->dev); |
131 | gpio->chip.ngpio = gpio->p_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 | ||
b8a34582 SD |
144 | static const struct pca9570_platform_data pca9570_gpio = { |
145 | .ngpio = 4, | |
146 | }; | |
147 | ||
148 | static const struct pca9570_platform_data pca9571_gpio = { | |
149 | .ngpio = 8, | |
150 | }; | |
151 | ||
fbb19fe1 SD |
152 | static const struct pca9570_platform_data slg7xl45106_gpio = { |
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}, |
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 }, |
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 | }, | |
178 | .probe_new = pca9570_probe, | |
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"); |