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
25static 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 = &reg;
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
52static 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
75static int tps65912_i2c_probe(struct i2c_client *i2c,
76			    const struct i2c_device_id *id)
77{
78	struct tps65912 *tps65912;
79
80	tps65912 = devm_kzalloc(&i2c->dev,
81				sizeof(struct tps65912), GFP_KERNEL);
82	if (tps65912 == NULL)
83		return -ENOMEM;
84
85	i2c_set_clientdata(i2c, tps65912);
86	tps65912->dev = &i2c->dev;
87	tps65912->control_data = i2c;
88	tps65912->read = tps65912_i2c_read;
89	tps65912->write = tps65912_i2c_write;
90
91	return tps65912_device_init(tps65912);
92}
93
94static int tps65912_i2c_remove(struct i2c_client *i2c)
95{
96	struct tps65912 *tps65912 = i2c_get_clientdata(i2c);
97
98	tps65912_device_exit(tps65912);
99
100	return 0;
101}
102
103static const struct i2c_device_id tps65912_i2c_id[] = {
104	{"tps65912", 0 },
105	{ }
106};
107MODULE_DEVICE_TABLE(i2c, tps65912_i2c_id);
108
109static struct i2c_driver tps65912_i2c_driver = {
110	.driver = {
111		   .name = "tps65912",
112	},
113	.probe = tps65912_i2c_probe,
114	.remove = tps65912_i2c_remove,
115	.id_table = tps65912_i2c_id,
116};
117
118static 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 */
129subsys_initcall(tps65912_i2c_init);
130
131static void __exit tps65912_i2c_exit(void)
132{
133	i2c_del_driver(&tps65912_i2c_driver);
134}
135module_exit(tps65912_i2c_exit);
136
137MODULE_AUTHOR("Margarita Olaya	<magi@slimlogic.co.uk>");
138MODULE_DESCRIPTION("TPS6591x chip family multi-function driver");
139MODULE_LICENSE("GPL");
140