xref: /openbmc/linux/drivers/media/i2c/ov7640.c (revision d6fc9fcb)
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 static const u8 initial_registers[] = {
17 	0x12, 0x80,
18 	0x12, 0x54,
19 	0x14, 0x24,
20 	0x15, 0x01,
21 	0x28, 0x20,
22 	0x75, 0x82,
23 	0xFF, 0xFF, /* Terminator (reg 0xFF is unused) */
24 };
25 
26 static int write_regs(struct i2c_client *client, const u8 *regs)
27 {
28 	int i;
29 
30 	for (i = 0; regs[i] != 0xFF; i += 2)
31 		if (i2c_smbus_write_byte_data(client, regs[i], regs[i + 1]) < 0)
32 			return -1;
33 	return 0;
34 }
35 
36 /* ----------------------------------------------------------------------- */
37 
38 static const struct v4l2_subdev_ops ov7640_ops;
39 
40 static int ov7640_probe(struct i2c_client *client,
41 			const struct i2c_device_id *id)
42 {
43 	struct i2c_adapter *adapter = client->adapter;
44 	struct v4l2_subdev *sd;
45 
46 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
47 		return -ENODEV;
48 
49 	sd = devm_kzalloc(&client->dev, sizeof(*sd), GFP_KERNEL);
50 	if (sd == NULL)
51 		return -ENOMEM;
52 	v4l2_i2c_subdev_init(sd, client, &ov7640_ops);
53 
54 	client->flags = I2C_CLIENT_SCCB;
55 
56 	v4l_info(client, "chip found @ 0x%02x (%s)\n",
57 			client->addr << 1, client->adapter->name);
58 
59 	if (write_regs(client, initial_registers) < 0) {
60 		v4l_err(client, "error initializing OV7640\n");
61 		return -ENODEV;
62 	}
63 
64 	return 0;
65 }
66 
67 
68 static int ov7640_remove(struct i2c_client *client)
69 {
70 	struct v4l2_subdev *sd = i2c_get_clientdata(client);
71 
72 	v4l2_device_unregister_subdev(sd);
73 
74 	return 0;
75 }
76 
77 static const struct i2c_device_id ov7640_id[] = {
78 	{ "ov7640", 0 },
79 	{ }
80 };
81 MODULE_DEVICE_TABLE(i2c, ov7640_id);
82 
83 static struct i2c_driver ov7640_driver = {
84 	.driver = {
85 		.name	= "ov7640",
86 	},
87 	.probe = ov7640_probe,
88 	.remove = ov7640_remove,
89 	.id_table = ov7640_id,
90 };
91 module_i2c_driver(ov7640_driver);
92