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 <media/v4l2-chip-ident.h>
37#include "tea6415c.h"
38
39MODULE_AUTHOR("Michael Hunold <michael@mihu.de>");
40MODULE_DESCRIPTION("tea6415c driver");
41MODULE_LICENSE("GPL");
42
43static int debug;
44module_param(debug, int, 0644);
45
46MODULE_PARM_DESC(debug, "Debug level (0-1)");
47
48
49/* makes a connection between the input-pin 'i' and the output-pin 'o' */
50static int tea6415c_s_routing(struct v4l2_subdev *sd,
51			      u32 i, u32 o, u32 config)
52{
53	struct i2c_client *client = v4l2_get_subdevdata(sd);
54	u8 byte = 0;
55	int ret;
56
57	v4l2_dbg(1, debug, sd, "i=%d, o=%d\n", i, o);
58
59	/* check if the pins are valid */
60	if (0 == ((1 == i ||  3 == i ||  5 == i ||  6 == i ||  8 == i || 10 == i || 20 == i || 11 == i)
61	      && (18 == o || 17 == o || 16 == o || 15 == o || 14 == o || 13 == o)))
62		return -EINVAL;
63
64	/* to understand this, have a look at the tea6415c-specs (p.5) */
65	switch (o) {
66	case 18:
67		byte = 0x00;
68		break;
69	case 14:
70		byte = 0x20;
71		break;
72	case 16:
73		byte = 0x10;
74		break;
75	case 17:
76		byte = 0x08;
77		break;
78	case 15:
79		byte = 0x18;
80		break;
81	case 13:
82		byte = 0x28;
83		break;
84	};
85
86	switch (i) {
87	case 5:
88		byte |= 0x00;
89		break;
90	case 8:
91		byte |= 0x04;
92		break;
93	case 3:
94		byte |= 0x02;
95		break;
96	case 20:
97		byte |= 0x06;
98		break;
99	case 6:
100		byte |= 0x01;
101		break;
102	case 10:
103		byte |= 0x05;
104		break;
105	case 1:
106		byte |= 0x03;
107		break;
108	case 11:
109		byte |= 0x07;
110		break;
111	};
112
113	ret = i2c_smbus_write_byte(client, byte);
114	if (ret) {
115		v4l2_dbg(1, debug, sd,
116			"i2c_smbus_write_byte() failed, ret:%d\n", ret);
117		return -EIO;
118	}
119	return ret;
120}
121
122static int tea6415c_g_chip_ident(struct v4l2_subdev *sd, struct v4l2_dbg_chip_ident *chip)
123{
124	struct i2c_client *client = v4l2_get_subdevdata(sd);
125
126	return v4l2_chip_ident_i2c_client(client, chip, V4L2_IDENT_TEA6415C, 0);
127}
128
129/* ----------------------------------------------------------------------- */
130
131static const struct v4l2_subdev_core_ops tea6415c_core_ops = {
132	.g_chip_ident = tea6415c_g_chip_ident,
133};
134
135static const struct v4l2_subdev_video_ops tea6415c_video_ops = {
136	.s_routing = tea6415c_s_routing,
137};
138
139static const struct v4l2_subdev_ops tea6415c_ops = {
140	.core = &tea6415c_core_ops,
141	.video = &tea6415c_video_ops,
142};
143
144static int tea6415c_probe(struct i2c_client *client,
145			  const struct i2c_device_id *id)
146{
147	struct v4l2_subdev *sd;
148
149	/* let's see whether this adapter can support what we need */
150	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WRITE_BYTE))
151		return -EIO;
152
153	v4l_info(client, "chip found @ 0x%x (%s)\n",
154			client->addr << 1, client->adapter->name);
155	sd = kzalloc(sizeof(struct v4l2_subdev), GFP_KERNEL);
156	if (sd == NULL)
157		return -ENOMEM;
158	v4l2_i2c_subdev_init(sd, client, &tea6415c_ops);
159	return 0;
160}
161
162static int tea6415c_remove(struct i2c_client *client)
163{
164	struct v4l2_subdev *sd = i2c_get_clientdata(client);
165
166	v4l2_device_unregister_subdev(sd);
167	kfree(sd);
168	return 0;
169}
170
171static const struct i2c_device_id tea6415c_id[] = {
172	{ "tea6415c", 0 },
173	{ }
174};
175MODULE_DEVICE_TABLE(i2c, tea6415c_id);
176
177static struct i2c_driver tea6415c_driver = {
178	.driver = {
179		.owner	= THIS_MODULE,
180		.name	= "tea6415c",
181	},
182	.probe		= tea6415c_probe,
183	.remove		= tea6415c_remove,
184	.id_table	= tea6415c_id,
185};
186
187module_i2c_driver(tea6415c_driver);
188