xref: /openbmc/linux/drivers/media/i2c/ov7640.c (revision 39b6f3aa)
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);
107