xref: /openbmc/linux/drivers/media/i2c/tea6415c.c (revision bbecb07f)
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 
38 MODULE_AUTHOR("Michael Hunold <michael@mihu.de>");
39 MODULE_DESCRIPTION("tea6415c driver");
40 MODULE_LICENSE("GPL");
41 
42 static int debug;
43 module_param(debug, int, 0644);
44 
45 MODULE_PARM_DESC(debug, "Debug level (0-1)");
46 
47 
48 /* makes a connection between the input-pin 'i' and the output-pin 'o' */
49 static 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 
123 static const struct v4l2_subdev_video_ops tea6415c_video_ops = {
124 	.s_routing = tea6415c_s_routing,
125 };
126 
127 static const struct v4l2_subdev_ops tea6415c_ops = {
128 	.video = &tea6415c_video_ops,
129 };
130 
131 static 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 
149 static 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 
157 static const struct i2c_device_id tea6415c_id[] = {
158 	{ "tea6415c", 0 },
159 	{ }
160 };
161 MODULE_DEVICE_TABLE(i2c, tea6415c_id);
162 
163 static struct i2c_driver tea6415c_driver = {
164 	.driver = {
165 		.name	= "tea6415c",
166 	},
167 	.probe		= tea6415c_probe,
168 	.remove		= tea6415c_remove,
169 	.id_table	= tea6415c_id,
170 };
171 
172 module_i2c_driver(tea6415c_driver);
173