drivers/media/i2c/ov7640.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) 2005-2006 Micronas USA Inc.
   4  */
   5
   6 #include <linux/init.h>
   7 #include <linux/module.h>
   8 #include <linux/i2c.h>
   9 #include <linux/videodev2.h>
  10 #include <media/v4l2-device.h>
  11 #include <linux/slab.h>
  12
  13 MODULE_DESCRIPTION("OmniVision ov7640 sensor driver");
  14 MODULE_LICENSE("GPL v2");
  15
  16 struct reg_val {
  17         u8 reg;
  18         u8 val;
  19 };
  20
  21 static const struct reg_val regval_init[] = {
  22         {0x12, 0x80},
  23         {0x12, 0x54},
  24         {0x14, 0x24},
  25         {0x15, 0x01},
  26         {0x28, 0x20},
  27         {0x75, 0x82},
  28 };
  29
  30 static int write_regs(struct i2c_client *client,
  31                 const struct reg_val *rv, int len)
  32 {
  33         while (--len >= 0) {
  34                 if (i2c_smbus_write_byte_data(client, rv->reg, rv->val) < 0)
  35                         return -1;
  36                 rv++;
  37         }
  38         return 0;
  39 }
  40
  41 /* ----------------------------------------------------------------------- */
  42
  43 static const struct v4l2_subdev_ops ov7640_ops;
  44
  45 static int ov7640_probe(struct i2c_client *client)
  46 {
  47         struct i2c_adapter *adapter = client->adapter;
  48         struct v4l2_subdev *sd;
  49
  50         if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
  51                 return -ENODEV;
  52
  53         sd = devm_kzalloc(&client->dev, sizeof(*sd), GFP_KERNEL);
  54         if (sd == NULL)
  55                 return -ENOMEM;
  56         v4l2_i2c_subdev_init(sd, client, &ov7640_ops);
  57
  58         client->flags = I2C_CLIENT_SCCB;
  59
  60         v4l_info(client, "chip found @ 0x%02x (%s)\n",
  61                         client->addr << 1, client->adapter->name);
  62
  63         if (write_regs(client, regval_init, ARRAY_SIZE(regval_init)) < 0) {
  64                 v4l_err(client, "error initializing OV7640\n");
  65                 return -ENODEV;
  66         }
  67
  68         return 0;
  69 }
  70
  71
  72 static void ov7640_remove(struct i2c_client *client)
  73 {
  74         struct v4l2_subdev *sd = i2c_get_clientdata(client);
  75
  76         v4l2_device_unregister_subdev(sd);
  77 }
  78
  79 static const struct i2c_device_id ov7640_id[] = {
  80         { "ov7640", 0 },
  81         { }
  82 };
  83 MODULE_DEVICE_TABLE(i2c, ov7640_id);
  84
  85 static struct i2c_driver ov7640_driver = {
  86         .driver = {
  87                 .name   = "ov7640",
  88         },
  89         .probe = ov7640_probe,
  90         .remove = ov7640_remove,
  91         .id_table = ov7640_id,
  92 };
  93 module_i2c_driver(ov7640_driver);