2 * wm831x-i2c.c -- I2C access for Wolfson WM831x PMICs
4 * Copyright 2009,2010 Wolfson Microelectronics PLC.
6 * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
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.
15 #include <linux/kernel.h>
16 #include <linux/module.h>
17 #include <linux/i2c.h>
18 #include <linux/delay.h>
19 #include <linux/mfd/core.h>
20 #include <linux/slab.h>
22 #include <linux/mfd/wm831x/core.h>
23 #include <linux/mfd/wm831x/pdata.h>
25 static int wm831x_i2c_read_device(struct wm831x *wm831x, unsigned short reg,
26 int bytes, void *dest)
28 struct i2c_client *i2c = wm831x->control_data;
30 u16 r = cpu_to_be16(reg);
32 ret = i2c_master_send(i2c, (unsigned char *)&r, 2);
38 ret = i2c_master_recv(i2c, dest, bytes);
46 /* Currently we allocate the write buffer on the stack; this is OK for
47 * small writes - if we need to do large writes this will need to be
50 static int wm831x_i2c_write_device(struct wm831x *wm831x, unsigned short reg,
53 struct i2c_client *i2c = wm831x->control_data;
54 struct i2c_msg xfer[2];
57 reg = cpu_to_be16(reg);
59 xfer[0].addr = i2c->addr;
62 xfer[0].buf = (char *)®
64 xfer[1].addr = i2c->addr;
65 xfer[1].flags = I2C_M_NOSTART;
67 xfer[1].buf = (char *)src;
69 ret = i2c_transfer(i2c->adapter, xfer, 2);
78 static int wm831x_i2c_probe(struct i2c_client *i2c,
79 const struct i2c_device_id *id)
81 struct wm831x *wm831x;
83 wm831x = kzalloc(sizeof(struct wm831x), GFP_KERNEL);
87 i2c_set_clientdata(i2c, wm831x);
88 wm831x->dev = &i2c->dev;
89 wm831x->control_data = i2c;
90 wm831x->read_dev = wm831x_i2c_read_device;
91 wm831x->write_dev = wm831x_i2c_write_device;
93 return wm831x_device_init(wm831x, id->driver_data, i2c->irq);
96 static int wm831x_i2c_remove(struct i2c_client *i2c)
98 struct wm831x *wm831x = i2c_get_clientdata(i2c);
100 wm831x_device_exit(wm831x);
105 static int wm831x_i2c_suspend(struct device *dev)
107 struct wm831x *wm831x = dev_get_drvdata(dev);
109 return wm831x_device_suspend(wm831x);
112 static const struct i2c_device_id wm831x_i2c_id[] = {
113 { "wm8310", WM8310 },
114 { "wm8311", WM8311 },
115 { "wm8312", WM8312 },
116 { "wm8320", WM8320 },
117 { "wm8321", WM8321 },
118 { "wm8325", WM8325 },
119 { "wm8326", WM8326 },
122 MODULE_DEVICE_TABLE(i2c, wm831x_i2c_id);
124 static const struct dev_pm_ops wm831x_pm_ops = {
125 .suspend = wm831x_i2c_suspend,
128 static struct i2c_driver wm831x_i2c_driver = {
131 .owner = THIS_MODULE,
132 .pm = &wm831x_pm_ops,
134 .probe = wm831x_i2c_probe,
135 .remove = wm831x_i2c_remove,
136 .id_table = wm831x_i2c_id,
139 static int __init wm831x_i2c_init(void)
143 ret = i2c_add_driver(&wm831x_i2c_driver);
145 pr_err("Failed to register wm831x I2C driver: %d\n", ret);
149 subsys_initcall(wm831x_i2c_init);
151 static void __exit wm831x_i2c_exit(void)
153 i2c_del_driver(&wm831x_i2c_driver);
155 module_exit(wm831x_i2c_exit);