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 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 = devm_kzalloc(&client->dev, 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         return ret;
  54 }
  55
  56 static int max7300_remove(struct i2c_client *client)
  57 {
  58         return __max730x_remove(&client->dev);
  59 }
  60
  61 static const struct i2c_device_id max7300_id[] = {
  62         { "max7300", 0 },
  63         { }
  64 };
  65 MODULE_DEVICE_TABLE(i2c, max7300_id);
  66
  67 static struct i2c_driver max7300_driver = {
  68         .driver = {
  69                 .name = "max7300",
  70                 .owner = THIS_MODULE,
  71         },
  72         .probe = max7300_probe,
  73         .remove = max7300_remove,
  74         .id_table = max7300_id,
  75 };
  76
  77 static int __init max7300_init(void)
  78 {
  79         return i2c_add_driver(&max7300_driver);
  80 }
  81 subsys_initcall(max7300_init);
  82
  83 static void __exit max7300_exit(void)
  84 {
  85         i2c_del_driver(&max7300_driver);
  86 }
  87 module_exit(max7300_exit);
  88
  89 MODULE_AUTHOR("Wolfram Sang");
  90 MODULE_LICENSE("GPL v2");
  91 MODULE_DESCRIPTION("MAX7300 GPIO-Expander");