aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/media/i2c/cs3308.c
blob: 7da5f69cace66862fdd966319c418054836d016e (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
/*
 * Cirrus Logic cs3308 8-Channel Analog Volume Control
 *
 * Copyright (C) 2010 Devin Heitmueller <dheitmueller@kernellabs.com>
 * Copyright (C) 2012 Steven Toth <stoth@kernellabs.com>
 *
 * Derived from cs5345.c Copyright (C) 2007 Hans Verkuil
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 */


#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/i2c.h>
#include <linux/slab.h>
#include <linux/videodev2.h>
#include <media/v4l2-device.h>

MODULE_DESCRIPTION("i2c device driver for cs3308 8-channel volume control");
MODULE_AUTHOR("Devin Heitmueller");
MODULE_LICENSE("GPL");

static inline int cs3308_write(struct v4l2_subdev *sd, u8 reg, u8 value)
{
	struct i2c_client *client = v4l2_get_subdevdata(sd);

	return i2c_smbus_write_byte_data(client, reg, value);
}

static inline int cs3308_read(struct v4l2_subdev *sd, u8 reg)
{
	struct i2c_client *client = v4l2_get_subdevdata(sd);

	return i2c_smbus_read_byte_data(client, reg);
}

#ifdef CONFIG_VIDEO_ADV_DEBUG
static int cs3308_g_register(struct v4l2_subdev *sd, struct v4l2_dbg_register *reg)
{
	reg->val = cs3308_read(sd, reg->reg & 0xffff);
	reg->size = 1;
	return 0;
}

static int cs3308_s_register(struct v4l2_subdev *sd, const struct v4l2_dbg_register *reg)
{
	cs3308_write(sd, reg->reg & 0xffff, reg->val & 0xff);
	return 0;
}
#endif

/* ----------------------------------------------------------------------- */

static const struct v4l2_subdev_core_ops cs3308_core_ops = {
#ifdef CONFIG_VIDEO_ADV_DEBUG
	.g_register = cs3308_g_register,
	.s_register = cs3308_s_register,
#endif
};

static const struct v4l2_subdev_ops cs3308_ops = {
	.core = &cs3308_core_ops,
};

/* ----------------------------------------------------------------------- */

static int cs3308_probe(struct i2c_client *client,
			const struct i2c_device_id *id)
{
	struct v4l2_subdev *sd;
	unsigned i;

	/* Check if the adapter supports the needed features */
	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
		return -EIO;

	if ((i2c_smbus_read_byte_data(client, 0x1c) & 0xf0) != 0xe0)
		return -ENODEV;

	v4l_info(client, "chip found @ 0x%x (%s)\n",
		 client->addr << 1, client->adapter->name);

	sd = kzalloc(sizeof(struct v4l2_subdev), GFP_KERNEL);
	if (sd == NULL)
		return -ENOMEM;

	v4l2_i2c_subdev_init(sd, client, &cs3308_ops);

	/* Set some reasonable defaults */
	cs3308_write(sd, 0x0d, 0x00); /* Power up all channels */
	cs3308_write(sd, 0x0e, 0x00); /* Master Power */
	cs3308_write(sd, 0x0b, 0x00); /* Device Configuration */
	/* Set volume for each channel */
	for (i = 1; i <= 8; i++)
		cs3308_write(sd, i, 0xd2);
	cs3308_write(sd, 0x0a, 0x00); /* Unmute all channels */
	return 0;
}

/* ----------------------------------------------------------------------- */

static int cs3308_remove(struct i2c_client *client)
{
	struct v4l2_subdev *sd = i2c_get_clientdata(client);

	v4l2_device_unregister_subdev(sd);
	kfree(sd);
	return 0;
}

/* ----------------------------------------------------------------------- */

static const struct i2c_device_id cs3308_id[] = {
	{ "cs3308", 0 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, cs3308_id);

static struct i2c_driver cs3308_driver = {
	.driver = {
		.name   = "cs3308",
	},
	.probe          = cs3308_probe,
	.remove         = cs3308_remove,
	.id_table       = cs3308_id,
};

module_i2c_driver(cs3308_driver);