xref: /openbmc/linux/drivers/media/i2c/ov7640.c (revision 94cdda6b)
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 <linux/slab.h>
24 
25 MODULE_DESCRIPTION("OmniVision ov7640 sensor driver");
26 MODULE_LICENSE("GPL v2");
27 
28 static const u8 initial_registers[] = {
29 	0x12, 0x80,
30 	0x12, 0x54,
31 	0x14, 0x24,
32 	0x15, 0x01,
33 	0x28, 0x20,
34 	0x75, 0x82,
35 	0xFF, 0xFF, /* Terminator (reg 0xFF is unused) */
36 };
37 
38 static int write_regs(struct i2c_client *client, const u8 *regs)
39 {
40 	int i;
41 
42 	for (i = 0; regs[i] != 0xFF; i += 2)
43 		if (i2c_smbus_write_byte_data(client, regs[i], regs[i + 1]) < 0)
44 			return -1;
45 	return 0;
46 }
47 
48 /* ----------------------------------------------------------------------- */
49 
50 static const struct v4l2_subdev_ops ov7640_ops;
51 
52 static int ov7640_probe(struct i2c_client *client,
53 			const struct i2c_device_id *id)
54 {
55 	struct i2c_adapter *adapter = client->adapter;
56 	struct v4l2_subdev *sd;
57 
58 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
59 		return -ENODEV;
60 
61 	sd = devm_kzalloc(&client->dev, sizeof(*sd), GFP_KERNEL);
62 	if (sd == NULL)
63 		return -ENOMEM;
64 	v4l2_i2c_subdev_init(sd, client, &ov7640_ops);
65 
66 	client->flags = I2C_CLIENT_SCCB;
67 
68 	v4l_info(client, "chip found @ 0x%02x (%s)\n",
69 			client->addr << 1, client->adapter->name);
70 
71 	if (write_regs(client, initial_registers) < 0) {
72 		v4l_err(client, "error initializing OV7640\n");
73 		return -ENODEV;
74 	}
75 
76 	return 0;
77 }
78 
79 
80 static int ov7640_remove(struct i2c_client *client)
81 {
82 	struct v4l2_subdev *sd = i2c_get_clientdata(client);
83 
84 	v4l2_device_unregister_subdev(sd);
85 
86 	return 0;
87 }
88 
89 static const struct i2c_device_id ov7640_id[] = {
90 	{ "ov7640", 0 },
91 	{ }
92 };
93 MODULE_DEVICE_TABLE(i2c, ov7640_id);
94 
95 static struct i2c_driver ov7640_driver = {
96 	.driver = {
97 		.owner	= THIS_MODULE,
98 		.name	= "ov7640",
99 	},
100 	.probe = ov7640_probe,
101 	.remove = ov7640_remove,
102 	.id_table = ov7640_id,
103 };
104 module_i2c_driver(ov7640_driver);
105