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  * You should have received a copy of the GNU General Public License
  14  * along with this program; if not, write to the Free Software Foundation,
  15  * Inc., 59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
  16  */
  17
  18 #include <linux/init.h>
  19 #include <linux/module.h>
  20 #include <linux/i2c.h>
  21 #include <linux/videodev2.h>
  22 #include <media/v4l2-device.h>
  23 #include <media/v4l2-chip-ident.h>
  24 #include <linux/slab.h>
  25
  26 MODULE_DESCRIPTION("OmniVision ov7640 sensor driver");
  27 MODULE_LICENSE("GPL v2");
  28
  29 static const u8 initial_registers[] = {
  30         0x12, 0x80,
  31         0x12, 0x54,
  32         0x14, 0x24,
  33         0x15, 0x01,
  34         0x28, 0x20,
  35         0x75, 0x82,
  36         0xFF, 0xFF, /* Terminator (reg 0xFF is unused) */
  37 };
  38
  39 static int write_regs(struct i2c_client *client, const u8 *regs)
  40 {
  41         int i;
  42
  43         for (i = 0; regs[i] != 0xFF; i += 2)
  44                 if (i2c_smbus_write_byte_data(client, regs[i], regs[i + 1]) < 0)
  45                         return -1;
  46         return 0;
  47 }
  48
  49 /* ----------------------------------------------------------------------- */
  50
  51 static const struct v4l2_subdev_ops ov7640_ops;
  52
  53 static int ov7640_probe(struct i2c_client *client,
  54                         const struct i2c_device_id *id)
  55 {
  56         struct i2c_adapter *adapter = client->adapter;
  57         struct v4l2_subdev *sd;
  58
  59         if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
  60                 return -ENODEV;
  61
  62         sd = kzalloc(sizeof(struct v4l2_subdev), GFP_KERNEL);
  63         if (sd == NULL)
  64                 return -ENOMEM;
  65         v4l2_i2c_subdev_init(sd, client, &ov7640_ops);
  66
  67         client->flags = I2C_CLIENT_SCCB;
  68
  69         v4l_info(client, "chip found @ 0x%02x (%s)\n",
  70                         client->addr << 1, client->adapter->name);
  71
  72         if (write_regs(client, initial_registers) < 0) {
  73                 v4l_err(client, "error initializing OV7640\n");
  74                 kfree(sd);
  75                 return -ENODEV;
  76         }
  77
  78         return 0;
  79 }
  80
  81
  82 static int ov7640_remove(struct i2c_client *client)
  83 {
  84         struct v4l2_subdev *sd = i2c_get_clientdata(client);
  85
  86         v4l2_device_unregister_subdev(sd);
  87         kfree(sd);
  88         return 0;
  89 }
  90
  91 static const struct i2c_device_id ov7640_id[] = {
  92         { "ov7640", 0 },
  93         { }
  94 };
  95 MODULE_DEVICE_TABLE(i2c, ov7640_id);
  96
  97 static struct i2c_driver ov7640_driver = {
  98         .driver = {
  99                 .owner  = THIS_MODULE,
 100                 .name   = "ov7640",
 101         },
 102         .probe = ov7640_probe,
 103         .remove = ov7640_remove,
 104         .id_table = ov7640_id,
 105 };
 106 module_i2c_driver(ov7640_driver);