LXR linux/drivers/mfd/wm8350-i2c.c

   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
  23static int wm8350_i2c_read_device(struct wm8350 *wm8350, char reg,
  24                                  int bytes, void *dest)
  25{
  26        int ret;
  27
  28        ret = i2c_master_send(wm8350->i2c_client, &reg, 1);
  29        if (ret < 0)
  30                return ret;
  31        ret = i2c_master_recv(wm8350->i2c_client, dest, bytes);
  32        if (ret < 0)
  33                return ret;
  34        if (ret != bytes)
  35                return -EIO;
  36        return 0;
  37}
  38
  39static int wm8350_i2c_write_device(struct wm8350 *wm8350, char reg,
  40                                   int bytes, void *src)
  41{
  42        /* we add 1 byte for device register */
  43        u8 msg[(WM8350_MAX_REGISTER << 1) + 1];
  44        int ret;
  45
  46        if (bytes > ((WM8350_MAX_REGISTER << 1) + 1))
  47                return -EINVAL;
  48
  49        msg[0] = reg;
  50        memcpy(&msg[1], src, bytes);
  51        ret = i2c_master_send(wm8350->i2c_client, msg, bytes + 1);
  52        if (ret < 0)
  53                return ret;
  54        if (ret != bytes + 1)
  55                return -EIO;
  56        return 0;
  57}
  58
  59static int wm8350_i2c_probe(struct i2c_client *i2c,
  60                            const struct i2c_device_id *id)
  61{
  62        struct wm8350 *wm8350;
  63        int ret = 0;
  64
  65        wm8350 = kzalloc(sizeof(struct wm8350), GFP_KERNEL);
  66        if (wm8350 == NULL) {
  67                kfree(i2c);
  68                return -ENOMEM;
  69        }
  70
  71        i2c_set_clientdata(i2c, wm8350);
  72        wm8350->dev = &i2c->dev;
  73        wm8350->i2c_client = i2c;
  74        wm8350->read_dev = wm8350_i2c_read_device;
  75        wm8350->write_dev = wm8350_i2c_write_device;
  76
  77        ret = wm8350_device_init(wm8350, i2c->irq, i2c->dev.platform_data);
  78        if (ret < 0)
  79                goto err;
  80
  81        return ret;
  82
  83err:
  84        kfree(wm8350);
  85        return ret;
  86}
  87
  88static int wm8350_i2c_remove(struct i2c_client *i2c)
  89{
  90        struct wm8350 *wm8350 = i2c_get_clientdata(i2c);
  91
  92        wm8350_device_exit(wm8350);
  93        kfree(wm8350);
  94
  95        return 0;
  96}
  97
  98static const struct i2c_device_id wm8350_i2c_id[] = {
  99       { "wm8350", 0 },
 100       { "wm8351", 0 },
 101       { "wm8352", 0 },
 102       { }
 103};
 104MODULE_DEVICE_TABLE(i2c, wm8350_i2c_id);
 105
 106
 107static struct i2c_driver wm8350_i2c_driver = {
 108        .driver = {
 109                   .name = "wm8350",
 110                   .owner = THIS_MODULE,
 111        },
 112        .probe = wm8350_i2c_probe,
 113        .remove = wm8350_i2c_remove,
 114        .id_table = wm8350_i2c_id,
 115};
 116
 117static int __init wm8350_i2c_init(void)
 118{
 119        return i2c_add_driver(&wm8350_i2c_driver);
 120}
 121/* init early so consumer devices can complete system boot */
 122subsys_initcall(wm8350_i2c_init);
 123
 124static void __exit wm8350_i2c_exit(void)
 125{
 126        i2c_del_driver(&wm8350_i2c_driver);
 127}
 128module_exit(wm8350_i2c_exit);
 129
 130MODULE_DESCRIPTION("I2C support for the WM8350 AudioPlus PMIC");
 131MODULE_LICENSE("GPL");
 132