1 /*
2 * tps65912-i2c.c -- I2C access for TI TPS65912x PMIC
3 *
4 * Copyright 2011 Texas Instruments Inc.
5 *
6 * Author: Margarita Olaya Cabrera <magi@slimlogic.co.uk>
7 *
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU General Public License as published by the
10 * Free Software Foundation; either version 2 of the License, or (at your
11 * option) any later version.
12 *
13 * This driver is based on wm8350 implementation.
14 */
15
16 #include <linux/module.h>
17 #include <linux/moduleparam.h>
18 #include <linux/init.h>
19 #include <linux/slab.h>
20 #include <linux/gpio.h>
21 #include <linux/i2c.h>
22 #include <linux/mfd/core.h>
23 #include <linux/mfd/tps65912.h>
24
tps65912_i2c_read(struct tps65912 * tps65912,u8 reg,int bytes,void * dest)25 static int tps65912_i2c_read(struct tps65912 *tps65912, u8 reg,
26 int bytes, void *dest)
27 {
28 struct i2c_client *i2c = tps65912->control_data;
29 struct i2c_msg xfer[2];
30 int ret;
31
32 /* Write register */
33 xfer[0].addr = i2c->addr;
34 xfer[0].flags = 0;
35 xfer[0].len = 1;
36 xfer[0].buf = ®
37
38 /* Read data */
39 xfer[1].addr = i2c->addr;
40 xfer[1].flags = I2C_M_RD;
41 xfer[1].len = bytes;
42 xfer[1].buf = dest;
43
44 ret = i2c_transfer(i2c->adapter, xfer, 2);
45 if (ret == 2)
46 ret = 0;
47 else if (ret >= 0)
48 ret = -EIO;
49 return ret;
50 }
51
tps65912_i2c_write(struct tps65912 * tps65912,u8 reg,int bytes,void * src)52 static int tps65912_i2c_write(struct tps65912 *tps65912, u8 reg,
53 int bytes, void *src)
54 {
55 struct i2c_client *i2c = tps65912->control_data;
56 /* we add 1 byte for device register */
57 u8 msg[TPS6591X_MAX_REGISTER + 1];
58 int ret;
59
60 if (bytes > TPS6591X_MAX_REGISTER)
61 return -EINVAL;
62
63 msg[0] = reg;
64 memcpy(&msg[1], src, bytes);
65
66 ret = i2c_master_send(i2c, msg, bytes + 1);
67 if (ret < 0)
68 return ret;
69 if (ret != bytes + 1)
70 return -EIO;
71
72 return 0;
73 }
74
tps65912_i2c_probe(struct i2c_client * i2c,const struct i2c_device_id * id)75 static int tps65912_i2c_probe(struct i2c_client *i2c,
76 const struct i2c_device_id *id)
77 {
78 struct tps65912 *tps65912;
79
80 tps65912 = kzalloc(sizeof(struct tps65912), GFP_KERNEL);
81 if (tps65912 == NULL)
82 return -ENOMEM;
83
84 i2c_set_clientdata(i2c, tps65912);
85 tps65912->dev = &i2c->dev;
86 tps65912->control_data = i2c;
87 tps65912->read = tps65912_i2c_read;
88 tps65912->write = tps65912_i2c_write;
89
90 return tps65912_device_init(tps65912);
91 }
92
tps65912_i2c_remove(struct i2c_client * i2c)93 static int tps65912_i2c_remove(struct i2c_client *i2c)
94 {
95 struct tps65912 *tps65912 = i2c_get_clientdata(i2c);
96
97 tps65912_device_exit(tps65912);
98
99 return 0;
100 }
101
102 static const struct i2c_device_id tps65912_i2c_id[] = {
103 {"tps65912", 0 },
104 { }
105 };
106 MODULE_DEVICE_TABLE(i2c, tps65912_i2c_id);
107
108 static struct i2c_driver tps65912_i2c_driver = {
109 .driver = {
110 .name = "tps65912",
111 .owner = THIS_MODULE,
112 },
113 .probe = tps65912_i2c_probe,
114 .remove = tps65912_i2c_remove,
115 .id_table = tps65912_i2c_id,
116 };
117
tps65912_i2c_init(void)118 static int __init tps65912_i2c_init(void)
119 {
120 int ret;
121
122 ret = i2c_add_driver(&tps65912_i2c_driver);
123 if (ret != 0)
124 pr_err("Failed to register TPS65912 I2C driver: %d\n", ret);
125
126 return ret;
127 }
128 /* init early so consumer devices can complete system boot */
129 subsys_initcall(tps65912_i2c_init);
130
tps65912_i2c_exit(void)131 static void __exit tps65912_i2c_exit(void)
132 {
133 i2c_del_driver(&tps65912_i2c_driver);
134 }
135 module_exit(tps65912_i2c_exit);
136
137 MODULE_AUTHOR("Margarita Olaya <magi@slimlogic.co.uk>");
138 MODULE_DESCRIPTION("TPS6591x chip family multi-function driver");
139 MODULE_LICENSE("GPL");
140