drivers/media/i2c/ov7640.c

   1 /*
   2  * Copyright (C) 2005-2006 Micronas USA Inc.
   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  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  */
  13
  14 #include <linux/init.h>
  15 #include <linux/module.h>
  16 #include <linux/i2c.h>
  17 #include <linux/videodev2.h>
  18 #include <media/v4l2-device.h>
  19 #include <linux/slab.h>
  20
  21 MODULE_DESCRIPTION("OmniVision ov7640 sensor driver");
  22 MODULE_LICENSE("GPL v2");
  23
  24 static const u8 initial_registers[] = {
  25         0x12, 0x80,
  26         0x12, 0x54,
  27         0x14, 0x24,
  28         0x15, 0x01,
  29         0x28, 0x20,
  30         0x75, 0x82,
  31         0xFF, 0xFF, /* Terminator (reg 0xFF is unused) */
  32 };
  33
  34 static int write_regs(struct i2c_client *client, const u8 *regs)
  35 {
  36         int i;
  37
  38         for (i = 0; regs[i] != 0xFF; i += 2)
  39                 if (i2c_smbus_write_byte_data(client, regs[i], regs[i + 1]) < 0)
  40                         return -1;
  41         return 0;
  42 }
  43
  44 /* ----------------------------------------------------------------------- */
  45
  46 static const struct v4l2_subdev_ops ov7640_ops;
  47
  48 static int ov7640_probe(struct i2c_client *client,
  49                         const struct i2c_device_id *id)
  50 {
  51         struct i2c_adapter *adapter = client->adapter;
  52         struct v4l2_subdev *sd;
  53
  54         if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
  55                 return -ENODEV;
  56
  57         sd = devm_kzalloc(&client->dev, sizeof(*sd), GFP_KERNEL);
  58         if (sd == NULL)
  59                 return -ENOMEM;
  60         v4l2_i2c_subdev_init(sd, client, &ov7640_ops);
  61
  62         client->flags = I2C_CLIENT_SCCB;
  63
  64         v4l_info(client, "chip found @ 0x%02x (%s)\n",
  65                         client->addr << 1, client->adapter->name);
  66
  67         if (write_regs(client, initial_registers) < 0) {
  68                 v4l_err(client, "error initializing OV7640\n");
  69                 return -ENODEV;
  70         }
  71
  72         return 0;
  73 }
  74
  75
  76 static int ov7640_remove(struct i2c_client *client)
  77 {
  78         struct v4l2_subdev *sd = i2c_get_clientdata(client);
  79
  80         v4l2_device_unregister_subdev(sd);
  81
  82         return 0;
  83 }
  84
  85 static const struct i2c_device_id ov7640_id[] = {
  86         { "ov7640", 0 },
  87         { }
  88 };
  89 MODULE_DEVICE_TABLE(i2c, ov7640_id);
  90
  91 static struct i2c_driver ov7640_driver = {
  92         .driver = {
  93                 .name   = "ov7640",
  94         },
  95         .probe = ov7640_probe,
  96         .remove = ov7640_remove,
  97         .id_table = ov7640_id,
  98 };
  99 module_i2c_driver(ov7640_driver);