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
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
|
/*
* I2C driver for Maxim MAX8925
*
* Copyright (C) 2009 Marvell International Ltd.
* Haojian Zhuang <haojian.zhuang@marvell.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/i2c.h>
#include <linux/mfd/max8925.h>
#include <linux/slab.h>
#define RTC_I2C_ADDR 0x68
#define ADC_I2C_ADDR 0x47
static inline int max8925_read_device(struct i2c_client *i2c,
int reg, int bytes, void *dest)
{
int ret;
if (bytes > 1)
ret = i2c_smbus_read_i2c_block_data(i2c, reg, bytes, dest);
else {
ret = i2c_smbus_read_byte_data(i2c, reg);
if (ret < 0)
return ret;
*(unsigned char *)dest = (unsigned char)ret;
}
return ret;
}
static inline int max8925_write_device(struct i2c_client *i2c,
int reg, int bytes, void *src)
{
unsigned char buf[bytes + 1];
int ret;
buf[0] = (unsigned char)reg;
memcpy(&buf[1], src, bytes);
ret = i2c_master_send(i2c, buf, bytes + 1);
if (ret < 0)
return ret;
return 0;
}
int max8925_reg_read(struct i2c_client *i2c, int reg)
{
struct max8925_chip *chip = i2c_get_clientdata(i2c);
unsigned char data = 0;
int ret;
mutex_lock(&chip->io_lock);
ret = max8925_read_device(i2c, reg, 1, &data);
mutex_unlock(&chip->io_lock);
if (ret < 0)
return ret;
else
return (int)data;
}
EXPORT_SYMBOL(max8925_reg_read);
int max8925_reg_write(struct i2c_client *i2c, int reg,
unsigned char data)
{
struct max8925_chip *chip = i2c_get_clientdata(i2c);
int ret;
mutex_lock(&chip->io_lock);
ret = max8925_write_device(i2c, reg, 1, &data);
mutex_unlock(&chip->io_lock);
return ret;
}
EXPORT_SYMBOL(max8925_reg_write);
int max8925_bulk_read(struct i2c_client *i2c, int reg,
int count, unsigned char *buf)
{
struct max8925_chip *chip = i2c_get_clientdata(i2c);
int ret;
mutex_lock(&chip->io_lock);
ret = max8925_read_device(i2c, reg, count, buf);
mutex_unlock(&chip->io_lock);
return ret;
}
EXPORT_SYMBOL(max8925_bulk_read);
int max8925_bulk_write(struct i2c_client *i2c, int reg,
int count, unsigned char *buf)
{
struct max8925_chip *chip = i2c_get_clientdata(i2c);
int ret;
mutex_lock(&chip->io_lock);
ret = max8925_write_device(i2c, reg, count, buf);
mutex_unlock(&chip->io_lock);
return ret;
}
EXPORT_SYMBOL(max8925_bulk_write);
int max8925_set_bits(struct i2c_client *i2c, int reg,
unsigned char mask, unsigned char data)
{
struct max8925_chip *chip = i2c_get_clientdata(i2c);
unsigned char value;
int ret;
mutex_lock(&chip->io_lock);
ret = max8925_read_device(i2c, reg, 1, &value);
if (ret < 0)
goto out;
value &= ~mask;
value |= data;
ret = max8925_write_device(i2c, reg, 1, &value);
out:
mutex_unlock(&chip->io_lock);
return ret;
}
EXPORT_SYMBOL(max8925_set_bits);
static const struct i2c_device_id max8925_id_table[] = {
{ "max8925", 0 },
{ },
};
MODULE_DEVICE_TABLE(i2c, max8925_id_table);
static int __devinit max8925_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct max8925_platform_data *pdata = client->dev.platform_data;
static struct max8925_chip *chip;
if (!pdata) {
pr_info("%s: platform data is missing\n", __func__);
return -EINVAL;
}
chip = kzalloc(sizeof(struct max8925_chip), GFP_KERNEL);
if (chip == NULL)
return -ENOMEM;
chip->i2c = client;
chip->dev = &client->dev;
i2c_set_clientdata(client, chip);
dev_set_drvdata(chip->dev, chip);
mutex_init(&chip->io_lock);
chip->rtc = i2c_new_dummy(chip->i2c->adapter, RTC_I2C_ADDR);
i2c_set_clientdata(chip->rtc, chip);
chip->adc = i2c_new_dummy(chip->i2c->adapter, ADC_I2C_ADDR);
i2c_set_clientdata(chip->adc, chip);
max8925_device_init(chip, pdata);
return 0;
}
static int __devexit max8925_remove(struct i2c_client *client)
{
struct max8925_chip *chip = i2c_get_clientdata(client);
max8925_device_exit(chip);
i2c_unregister_device(chip->adc);
i2c_unregister_device(chip->rtc);
i2c_set_clientdata(chip->i2c, NULL);
kfree(chip);
return 0;
}
static struct i2c_driver max8925_driver = {
.driver = {
.name = "max8925",
.owner = THIS_MODULE,
},
.probe = max8925_probe,
.remove = __devexit_p(max8925_remove),
.id_table = max8925_id_table,
};
static int __init max8925_i2c_init(void)
{
int ret;
ret = i2c_add_driver(&max8925_driver);
if (ret != 0)
pr_err("Failed to register MAX8925 I2C driver: %d\n", ret);
return ret;
}
subsys_initcall(max8925_i2c_init);
static void __exit max8925_i2c_exit(void)
{
i2c_del_driver(&max8925_driver);
}
module_exit(max8925_i2c_exit);
MODULE_DESCRIPTION("I2C Driver for Maxim 8925");
MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>");
MODULE_LICENSE("GPL");
|
