drivers/mfd/wm8350-i2c.c

   1 /*
   2  * wm8350-i2c.c  --  Generic I2C driver for Wolfson WM8350 PMIC
   3  *
   4  * This driver defines and configures the WM8350 for the Freescale i.MX32ADS.
   5  *
   6  * Copyright 2007, 2008 Wolfson Microelectronics PLC.
   7  *
   8  * Author: Liam Girdwood
   9  *         linux@wolfsonmicro.com
  10  *
  11  *  This program is free software; you can redistribute  it and/or modify it
  12  *  under  the terms of  the GNU General  Public License as published by the
  13  *  Free Software Foundation;  either version 2 of the  License, or (at your
  14  *  option) any later version.
  15  *
  16  */
  17
  18 #include <linux/module.h>
  19 #include <linux/moduleparam.h>
  20 #include <linux/init.h>
  21 #include <linux/i2c.h>
  22 #include <linux/platform_device.h>
  23 #include <linux/mfd/wm8350/core.h>
  24
  25 static int wm8350_i2c_read_device(struct wm8350 *wm8350, char reg,
  26                                   int bytes, void *dest)
  27 {
  28         int ret;
  29
  30         ret = i2c_master_send(wm8350->i2c_client, &reg, 1);
  31         if (ret < 0)
  32                 return ret;
  33         return i2c_master_recv(wm8350->i2c_client, dest, bytes);
  34 }
  35
  36 static int wm8350_i2c_write_device(struct wm8350 *wm8350, char reg,
  37                                    int bytes, void *src)
  38 {
  39         /* we add 1 byte for device register */
  40         u8 msg[(WM8350_MAX_REGISTER << 1) + 1];
  41
  42         if (bytes > ((WM8350_MAX_REGISTER << 1) + 1))
  43                 return -EINVAL;
  44
  45         msg[0] = reg;
  46         memcpy(&msg[1], src, bytes);
  47         return i2c_master_send(wm8350->i2c_client, msg, bytes + 1);
  48 }
  49
  50 static int wm8350_i2c_probe(struct i2c_client *i2c,
  51                             const struct i2c_device_id *id)
  52 {
  53         struct wm8350 *wm8350;
  54         int ret = 0;
  55
  56         wm8350 = kzalloc(sizeof(struct wm8350), GFP_KERNEL);
  57         if (wm8350 == NULL) {
  58                 kfree(i2c);
  59                 return -ENOMEM;
  60         }
  61
  62         i2c_set_clientdata(i2c, wm8350);
  63         wm8350->dev = &i2c->dev;
  64         wm8350->i2c_client = i2c;
  65         wm8350->read_dev = wm8350_i2c_read_device;
  66         wm8350->write_dev = wm8350_i2c_write_device;
  67
  68         ret = wm8350_device_init(wm8350, i2c->irq, i2c->dev.platform_data);
  69         if (ret < 0)
  70                 goto err;
  71
  72         return ret;
  73
  74 err:
  75         kfree(wm8350);
  76         return ret;
  77 }
  78
  79 static int wm8350_i2c_remove(struct i2c_client *i2c)
  80 {
  81         struct wm8350 *wm8350 = i2c_get_clientdata(i2c);
  82
  83         wm8350_device_exit(wm8350);
  84         kfree(wm8350);
  85
  86         return 0;
  87 }
  88
  89 static const struct i2c_device_id wm8350_i2c_id[] = {
  90        { "wm8350", 0 },
  91        { }
  92 };
  93 MODULE_DEVICE_TABLE(i2c, wm8350_i2c_id);
  94
  95
  96 static struct i2c_driver wm8350_i2c_driver = {
  97         .driver = {
  98                    .name = "wm8350",
  99                    .owner = THIS_MODULE,
 100         },
 101         .probe = wm8350_i2c_probe,
 102         .remove = wm8350_i2c_remove,
 103         .id_table = wm8350_i2c_id,
 104 };
 105
 106 static int __init wm8350_i2c_init(void)
 107 {
 108         return i2c_add_driver(&wm8350_i2c_driver);
 109 }
 110 /* init early so consumer devices can complete system boot */
 111 subsys_initcall(wm8350_i2c_init);
 112
 113 static void __exit wm8350_i2c_exit(void)
 114 {
 115         i2c_del_driver(&wm8350_i2c_driver);
 116 }
 117 module_exit(wm8350_i2c_exit);
 118
 119 MODULE_DESCRIPTION("I2C support for the WM8350 AudioPlus PMIC");
 120 MODULE_LICENSE("GPL");