1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
|
// SPDX-License-Identifier: GPL-2.0-only
/*
* 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>
#define TPIC2810_WS_COMMAND 0x44
/**
* struct tpic2810 - GPIO driver data
* @chip: GPIO controller chip
* @client: I2C device pointer
* @buffer: Buffer for device register
* @lock: Protects write sequences
*/
struct tpic2810 {
struct gpio_chip chip;
struct i2c_client *client;
u8 buffer;
struct mutex lock;
};
static void tpic2810_set(struct gpio_chip *chip, unsigned offset, int value);
static int tpic2810_get_direction(struct gpio_chip *chip,
unsigned offset)
{
/* This device always output */
return GPIO_LINE_DIRECTION_OUT;
}
static int tpic2810_direction_input(struct gpio_chip *chip,
unsigned offset)
{
/* This device is output only */
return -EINVAL;
}
static int tpic2810_direction_output(struct gpio_chip *chip,
unsigned offset, int value)
{
/* This device always output */
tpic2810_set(chip, offset, value);
return 0;
}
static void tpic2810_set_mask_bits(struct gpio_chip *chip, u8 mask, u8 bits)
{
struct tpic2810 *gpio = gpiochip_get_data(chip);
u8 buffer;
int err;
mutex_lock(&gpio->lock);
buffer = gpio->buffer & ~mask;
buffer |= (mask & bits);
err = i2c_smbus_write_byte_data(gpio->client, TPIC2810_WS_COMMAND,
buffer);
if (!err)
gpio->buffer = buffer;
mutex_unlock(&gpio->lock);
}
static void tpic2810_set(struct gpio_chip *chip, unsigned offset, int value)
{
tpic2810_set_mask_bits(chip, BIT(offset), value ? BIT(offset) : 0);
}
static void tpic2810_set_multiple(struct gpio_chip *chip, unsigned long *mask,
unsigned long *bits)
{
tpic2810_set_mask_bits(chip, *mask, *bits);
}
static const struct gpio_chip template_chip = {
.label = "tpic2810",
.owner = THIS_MODULE,
.get_direction = tpic2810_get_direction,
.direction_input = tpic2810_direction_input,
.direction_output = tpic2810_direction_output,
.set = tpic2810_set,
.set_multiple = tpic2810_set_multiple,
.base = -1,
.ngpio = 8,
.can_sleep = true,
};
static const struct of_device_id tpic2810_of_match_table[] = {
{ .compatible = "ti,tpic2810" },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, tpic2810_of_match_table);
static int tpic2810_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct tpic2810 *gpio;
int ret;
gpio = devm_kzalloc(&client->dev, sizeof(*gpio), GFP_KERNEL);
if (!gpio)
return -ENOMEM;
i2c_set_clientdata(client, gpio);
gpio->chip = template_chip;
gpio->chip.parent = &client->dev;
gpio->client = client;
mutex_init(&gpio->lock);
ret = gpiochip_add_data(&gpio->chip, gpio);
if (ret < 0) {
dev_err(&client->dev, "Unable to register gpiochip\n");
return ret;
}
return 0;
}
static void tpic2810_remove(struct i2c_client *client)
{
struct tpic2810 *gpio = i2c_get_clientdata(client);
gpiochip_remove(&gpio->chip);
}
static const struct i2c_device_id tpic2810_id_table[] = {
{ "tpic2810", },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(i2c, tpic2810_id_table);
static struct i2c_driver tpic2810_driver = {
.driver = {
.name = "tpic2810",
.of_match_table = tpic2810_of_match_table,
},
.probe = tpic2810_probe,
.remove = tpic2810_remove,
.id_table = tpic2810_id_table,
};
module_i2c_driver(tpic2810_driver);
MODULE_AUTHOR("Andrew F. Davis <afd@ti.com>");
MODULE_DESCRIPTION("TPIC2810 8-Bit LED Driver GPIO Driver");
MODULE_LICENSE("GPL v2");
|
