drivers/gpio/max7300.c

   1 /*
   2  * drivers/gpio/max7300.c
   3  *
   4  * Copyright (C) 2009 Wolfram Sang, Pengutronix
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  *
  10  * Check max730x.c for further details.
  11  */
  12
  13 #include <linux/module.h>
  14 #include <linux/init.h>
  15 #include <linux/platform_device.h>
  16 #include <linux/mutex.h>
  17 #include <linux/i2c.h>
  18 #include <linux/spi/max7301.h>
  19 #include <linux/slab.h>
  20
  21 static int max7300_i2c_write(struct device *dev, unsigned int reg,
  22                                 unsigned int val)
  23 {
  24         struct i2c_client *client = to_i2c_client(dev);
  25
  26         return i2c_smbus_write_byte_data(client, reg, val);
  27 }
  28
  29 static int max7300_i2c_read(struct device *dev, unsigned int reg)
  30 {
  31         struct i2c_client *client = to_i2c_client(dev);
  32
  33         return i2c_smbus_read_byte_data(client, reg);
  34 }
  35
  36 static int __devinit max7300_probe(struct i2c_client *client,
  37                          const struct i2c_device_id *id)
  38 {
  39         struct max7301 *ts;
  40         int ret;
  41
  42         if (!i2c_check_functionality(client->adapter,
  43                         I2C_FUNC_SMBUS_BYTE_DATA))
  44                 return -EIO;
  45
  46         ts = kzalloc(sizeof(struct max7301), GFP_KERNEL);
  47         if (!ts)
  48                 return -ENOMEM;
  49
  50         ts->read = max7300_i2c_read;
  51         ts->write = max7300_i2c_write;
  52         ts->dev = &client->dev;
  53
  54         ret = __max730x_probe(ts);
  55         if (ret)
  56                 kfree(ts);
  57         return ret;
  58 }
  59
  60 static int __devexit max7300_remove(struct i2c_client *client)
  61 {
  62         return __max730x_remove(&client->dev);
  63 }
  64
  65 static const struct i2c_device_id max7300_id[] = {
  66         { "max7300", 0 },
  67         { }
  68 };
  69 MODULE_DEVICE_TABLE(i2c, max7300_id);
  70
  71 static struct i2c_driver max7300_driver = {
  72         .driver = {
  73                 .name = "max7300",
  74                 .owner = THIS_MODULE,
  75         },
  76         .probe = max7300_probe,
  77         .remove = __devexit_p(max7300_remove),
  78         .id_table = max7300_id,
  79 };
  80
  81 static int __init max7300_init(void)
  82 {
  83         return i2c_add_driver(&max7300_driver);
  84 }
  85 subsys_initcall(max7300_init);
  86
  87 static void __exit max7300_exit(void)
  88 {
  89         i2c_del_driver(&max7300_driver);
  90 }
  91 module_exit(max7300_exit);
  92
  93 MODULE_AUTHOR("Wolfram Sang");
  94 MODULE_LICENSE("GPL v2");
  95 MODULE_DESCRIPTION("MAX7300 GPIO-Expander");