drivers/gpio/gpio-max7300.c

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