summaryrefslogtreecommitdiffstats
path: root/drivers/media/video/tea6415c.c
blob: cde092adbb5abffdd1aafaf0b21d2b566ff20bcd (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
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
 /*
    tea6415c - i2c-driver for the tea6415c by SGS Thomson

    Copyright (C) 1998-2003 Michael Hunold <michael@mihu.de>
    Copyright (C) 2008 Hans Verkuil <hverkuil@xs4all.nl>

    The tea6415c is a bus controlled video-matrix-switch
    with 8 inputs and 6 outputs.
    It is cascadable, i.e. it can be found at the addresses
    0x86 and 0x06 on the i2c-bus.

    For detailed informations download the specifications directly
    from SGS Thomson at http://www.st.com

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License vs 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.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 675 Mvss Ave, Cambridge, MA 02139, USA.
  */


#include <linux/module.h>
#include <linux/ioctl.h>
#include <linux/i2c.h>
#include <media/v4l2-common.h>
#include <media/v4l2-i2c-drv-legacy.h>
#include "tea6415c.h"

MODULE_AUTHOR("Michael Hunold <michael@mihu.de>");
MODULE_DESCRIPTION("tea6415c driver");
MODULE_LICENSE("GPL");

static int debug;
module_param(debug, int, 0644);

MODULE_PARM_DESC(debug, "Debug level (0-1)");

/* addresses to scan, found only at 0x03 and/or 0x43 (7-bit) */
static unsigned short normal_i2c[] = { I2C_TEA6415C_1, I2C_TEA6415C_2, I2C_CLIENT_END };

/* magic definition of all other variables and things */
I2C_CLIENT_INSMOD;

/* makes a connection between the input-pin 'i' and the output-pin 'o'
   for the tea6415c-client 'client' */
static int switch_matrix(struct i2c_client *client, int i, int o)
{
	u8 byte = 0;
	int ret;

	v4l_dbg(1, debug, client, "i=%d, o=%d\n", i, o);

	/* check if the pins are valid */
	if (0 == ((1 == i ||  3 == i ||  5 == i ||  6 == i ||  8 == i || 10 == i || 20 == i || 11 == i)
	      && (18 == o || 17 == o || 16 == o || 15 == o || 14 == o || 13 == o)))
		return -1;

	/* to understand this, have a look at the tea6415c-specs (p.5) */
	switch (o) {
	case 18:
		byte = 0x00;
		break;
	case 14:
		byte = 0x20;
		break;
	case 16:
		byte = 0x10;
		break;
	case 17:
		byte = 0x08;
		break;
	case 15:
		byte = 0x18;
		break;
	case 13:
		byte = 0x28;
		break;
	};

	switch (i) {
	case 5:
		byte |= 0x00;
		break;
	case 8:
		byte |= 0x04;
		break;
	case 3:
		byte |= 0x02;
		break;
	case 20:
		byte |= 0x06;
		break;
	case 6:
		byte |= 0x01;
		break;
	case 10:
		byte |= 0x05;
		break;
	case 1:
		byte |= 0x03;
		break;
	case 11:
		byte |= 0x07;
		break;
	};

	ret = i2c_smbus_write_byte(client, byte);
	if (ret) {
		v4l_dbg(1, debug, client,
			"i2c_smbus_write_byte() failed, ret:%d\n", ret);
		return -EIO;
	}
	return ret;
}

static int tea6415c_command(struct i2c_client *client, unsigned cmd, void *arg)
{
	struct tea6415c_multiplex *v = (struct tea6415c_multiplex *)arg;
	int result = 0;

	switch (cmd) {
	case TEA6415C_SWITCH:
		result = switch_matrix(client, v->in, v->out);
		break;
	default:
		return -ENOIOCTLCMD;
	}
	return result;
}

/* this function is called by i2c_probe */
static int tea6415c_probe(struct i2c_client *client,
			  const struct i2c_device_id *id)
{
	/* let's see whether this adapter can support what we need */
	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WRITE_BYTE))
		return 0;

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

static int tea6415c_legacy_probe(struct i2c_adapter *adapter)
{
	/* Let's see whether this is a known adapter we can attach to.
	   Prevents conflicts with tvaudio.c. */
	return adapter->id == I2C_HW_SAA7146;
}

static const struct i2c_device_id tea6415c_id[] = {
	{ "tea6415c", 0 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, tea6415c_id);

static struct v4l2_i2c_driver_data v4l2_i2c_data = {
	.name = "tea6415c",
	.driverid = I2C_DRIVERID_TEA6415C,
	.command = tea6415c_command,
	.probe = tea6415c_probe,
	.legacy_probe = tea6415c_legacy_probe,
	.id_table = tea6415c_id,
};