1 /*
2    tea6415c - i2c-driver for the tea6415c by SGS Thomson
3
4    Copyright (C) 1998-2003 Michael Hunold <michael@mihu.de>
5    Copyright (C) 2008 Hans Verkuil <hverkuil@xs4all.nl>
6
7    The tea6415c is a bus controlled video-matrix-switch
8    with 8 inputs and 6 outputs.
9    It is cascadable, i.e. it can be found at the addresses
10    0x86 and 0x06 on the i2c-bus.
11
12    For detailed informations download the specifications directly
13    from SGS Thomson at http://www.st.com
14
15    This program is free software; you can redistribute it and/or modify
16    it under the terms of the GNU General Public License vs published by
17    the Free Software Foundation; either version 2 of the License, or
18    (at your option) any later version.
19
20    This program is distributed in the hope that it will be useful,
21    but WITHOUT ANY WARRANTY; without even the implied warranty of
22    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
23    GNU General Public License for more details.
24
25    You should have received a copy of the GNU General Public License
26    along with this program; if not, write to the Free Software
27    Foundation, Inc., 675 Mvss Ave, Cambridge, MA 02139, USA.
28  */
29
30
31#include <linux/module.h>
32#include <linux/ioctl.h>
33#include <linux/slab.h>
34#include <linux/i2c.h>
35#include <media/v4l2-device.h>
36#include "tea6415c.h"
37
38MODULE_AUTHOR("Michael Hunold <michael@mihu.de>");
39MODULE_DESCRIPTION("tea6415c driver");
40MODULE_LICENSE("GPL");
41
42static int debug;
43module_param(debug, int, 0644);
44
45MODULE_PARM_DESC(debug, "Debug level (0-1)");
46
47
48/* makes a connection between the input-pin 'i' and the output-pin 'o' */
49static int tea6415c_s_routing(struct v4l2_subdev *sd,
50			      u32 i, u32 o, u32 config)
51{
52	struct i2c_client *client = v4l2_get_subdevdata(sd);
53	u8 byte = 0;
54	int ret;
55
56	v4l2_dbg(1, debug, sd, "i=%d, o=%d\n", i, o);
57
58	/* check if the pins are valid */
59	if (0 == ((1 == i ||  3 == i ||  5 == i ||  6 == i ||  8 == i || 10 == i || 20 == i || 11 == i)
60	      && (18 == o || 17 == o || 16 == o || 15 == o || 14 == o || 13 == o)))
61		return -EINVAL;
62
63	/* to understand this, have a look at the tea6415c-specs (p.5) */
64	switch (o) {
65	case 18:
66		byte = 0x00;
67		break;
68	case 14:
69		byte = 0x20;
70		break;
71	case 16:
72		byte = 0x10;
73		break;
74	case 17:
75		byte = 0x08;
76		break;
77	case 15:
78		byte = 0x18;
79		break;
80	case 13:
81		byte = 0x28;
82		break;
83	}
84
85	switch (i) {
86	case 5:
87		byte |= 0x00;
88		break;
89	case 8:
90		byte |= 0x04;
91		break;
92	case 3:
93		byte |= 0x02;
94		break;
95	case 20:
96		byte |= 0x06;
97		break;
98	case 6:
99		byte |= 0x01;
100		break;
101	case 10:
102		byte |= 0x05;
103		break;
104	case 1:
105		byte |= 0x03;
106		break;
107	case 11:
108		byte |= 0x07;
109		break;
110	}
111
112	ret = i2c_smbus_write_byte(client, byte);
113	if (ret) {
114		v4l2_dbg(1, debug, sd,
115			"i2c_smbus_write_byte() failed, ret:%d\n", ret);
116		return -EIO;
117	}
118	return ret;
119}
120
121/* ----------------------------------------------------------------------- */
122
123static const struct v4l2_subdev_video_ops tea6415c_video_ops = {
124	.s_routing = tea6415c_s_routing,
125};
126
127static const struct v4l2_subdev_ops tea6415c_ops = {
128	.video = &tea6415c_video_ops,
129};
130
131static int tea6415c_probe(struct i2c_client *client,
132			  const struct i2c_device_id *id)
133{
134	struct v4l2_subdev *sd;
135
136	/* let's see whether this adapter can support what we need */
137	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WRITE_BYTE))
138		return -EIO;
139
140	v4l_info(client, "chip found @ 0x%x (%s)\n",
141			client->addr << 1, client->adapter->name);
142	sd = devm_kzalloc(&client->dev, sizeof(*sd), GFP_KERNEL);
143	if (sd == NULL)
144		return -ENOMEM;
145	v4l2_i2c_subdev_init(sd, client, &tea6415c_ops);
146	return 0;
147}
148
149static int tea6415c_remove(struct i2c_client *client)
150{
151	struct v4l2_subdev *sd = i2c_get_clientdata(client);
152
153	v4l2_device_unregister_subdev(sd);
154	return 0;
155}
156
157static const struct i2c_device_id tea6415c_id[] = {
158	{ "tea6415c", 0 },
159	{ }
160};
161MODULE_DEVICE_TABLE(i2c, tea6415c_id);
162
163static struct i2c_driver tea6415c_driver = {
164	.driver = {
165		.owner	= THIS_MODULE,
166		.name	= "tea6415c",
167	},
168	.probe		= tea6415c_probe,
169	.remove		= tea6415c_remove,
170	.id_table	= tea6415c_id,
171};
172
173module_i2c_driver(tea6415c_driver);
174