1 /*
2  * wm8350-i2c.c  --  Generic I2C driver for Wolfson WM8350 PMIC
3  *
4  * Copyright 2007, 2008 Wolfson Microelectronics PLC.
5  *
6  * Author: Liam Girdwood
7  *         linux@wolfsonmicro.com
8  *
9  *  This program is free software; you can redistribute  it and/or modify it
10  *  under  the terms of  the GNU General  Public License as published by the
11  *  Free Software Foundation;  either version 2 of the  License, or (at your
12  *  option) any later version.
13  *
14  */
15 
16 #include <linux/module.h>
17 #include <linux/moduleparam.h>
18 #include <linux/init.h>
19 #include <linux/i2c.h>
20 #include <linux/platform_device.h>
21 #include <linux/mfd/wm8350/core.h>
22 #include <linux/slab.h>
23 
wm8350_i2c_read_device(struct wm8350 * wm8350,char reg,int bytes,void * dest)24 static int wm8350_i2c_read_device(struct wm8350 *wm8350, char reg,
25 				  int bytes, void *dest)
26 {
27 	int ret;
28 
29 	ret = i2c_master_send(wm8350->i2c_client, &reg, 1);
30 	if (ret < 0)
31 		return ret;
32 	ret = i2c_master_recv(wm8350->i2c_client, dest, bytes);
33 	if (ret < 0)
34 		return ret;
35 	if (ret != bytes)
36 		return -EIO;
37 	return 0;
38 }
39 
wm8350_i2c_write_device(struct wm8350 * wm8350,char reg,int bytes,void * src)40 static int wm8350_i2c_write_device(struct wm8350 *wm8350, char reg,
41 				   int bytes, void *src)
42 {
43 	/* we add 1 byte for device register */
44 	u8 msg[(WM8350_MAX_REGISTER << 1) + 1];
45 	int ret;
46 
47 	if (bytes > ((WM8350_MAX_REGISTER << 1) + 1))
48 		return -EINVAL;
49 
50 	msg[0] = reg;
51 	memcpy(&msg[1], src, bytes);
52 	ret = i2c_master_send(wm8350->i2c_client, msg, bytes + 1);
53 	if (ret < 0)
54 		return ret;
55 	if (ret != bytes + 1)
56 		return -EIO;
57 	return 0;
58 }
59 
wm8350_i2c_probe(struct i2c_client * i2c,const struct i2c_device_id * id)60 static int wm8350_i2c_probe(struct i2c_client *i2c,
61 			    const struct i2c_device_id *id)
62 {
63 	struct wm8350 *wm8350;
64 	int ret = 0;
65 
66 	wm8350 = devm_kzalloc(&i2c->dev, sizeof(struct wm8350), GFP_KERNEL);
67 	if (wm8350 == NULL)
68 		return -ENOMEM;
69 
70 	i2c_set_clientdata(i2c, wm8350);
71 	wm8350->dev = &i2c->dev;
72 	wm8350->i2c_client = i2c;
73 	wm8350->read_dev = wm8350_i2c_read_device;
74 	wm8350->write_dev = wm8350_i2c_write_device;
75 
76 	ret = wm8350_device_init(wm8350, i2c->irq, i2c->dev.platform_data);
77 	if (ret < 0)
78 		goto err;
79 
80 	return ret;
81 
82 err:
83 	return ret;
84 }
85 
wm8350_i2c_remove(struct i2c_client * i2c)86 static int wm8350_i2c_remove(struct i2c_client *i2c)
87 {
88 	struct wm8350 *wm8350 = i2c_get_clientdata(i2c);
89 
90 	wm8350_device_exit(wm8350);
91 
92 	return 0;
93 }
94 
95 static const struct i2c_device_id wm8350_i2c_id[] = {
96        { "wm8350", 0 },
97        { "wm8351", 0 },
98        { "wm8352", 0 },
99        { }
100 };
101 MODULE_DEVICE_TABLE(i2c, wm8350_i2c_id);
102 
103 
104 static struct i2c_driver wm8350_i2c_driver = {
105 	.driver = {
106 		   .name = "wm8350",
107 		   .owner = THIS_MODULE,
108 	},
109 	.probe = wm8350_i2c_probe,
110 	.remove = wm8350_i2c_remove,
111 	.id_table = wm8350_i2c_id,
112 };
113 
wm8350_i2c_init(void)114 static int __init wm8350_i2c_init(void)
115 {
116 	return i2c_add_driver(&wm8350_i2c_driver);
117 }
118 /* init early so consumer devices can complete system boot */
119 subsys_initcall(wm8350_i2c_init);
120 
wm8350_i2c_exit(void)121 static void __exit wm8350_i2c_exit(void)
122 {
123 	i2c_del_driver(&wm8350_i2c_driver);
124 }
125 module_exit(wm8350_i2c_exit);
126 
127 MODULE_DESCRIPTION("I2C support for the WM8350 AudioPlus PMIC");
128 MODULE_LICENSE("GPL");
129