1// SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 tea6415c - i2c-driver for the tea6415c by SGS Thomson
4
5 Copyright (C) 1998-2003 Michael Hunold <michael@mihu.de>
6 Copyright (C) 2008 Hans Verkuil <hverkuil@xs4all.nl>
7
8 The tea6415c is a bus controlled video-matrix-switch
9 with 8 inputs and 6 outputs.
10 It is cascadable, i.e. it can be found at the addresses
11 0x86 and 0x06 on the i2c-bus.
12
13 For detailed information download the specifications directly
14 from SGS Thomson at http://www.st.com
15
16 */
17
18
19#include <linux/module.h>
20#include <linux/ioctl.h>
21#include <linux/slab.h>
22#include <linux/i2c.h>
23#include <media/v4l2-device.h>
24#include "tea6415c.h"
25
26MODULE_AUTHOR("Michael Hunold <michael@mihu.de>");
27MODULE_DESCRIPTION("tea6415c driver");
28MODULE_LICENSE("GPL");
29
30static int debug;
31module_param(debug, int, 0644);
32
33MODULE_PARM_DESC(debug, "Debug level (0-1)");
34
35
36/* makes a connection between the input-pin 'i' and the output-pin 'o' */
37static int tea6415c_s_routing(struct v4l2_subdev *sd,
38 u32 i, u32 o, u32 config)
39{
40 struct i2c_client *client = v4l2_get_subdevdata(sd);
41 u8 byte = 0;
42 int ret;
43
44 v4l2_dbg(1, debug, sd, "i=%d, o=%d\n", i, o);
45
46 /* check if the pins are valid */
47 if (0 == ((1 == i || 3 == i || 5 == i || 6 == i || 8 == i || 10 == i || 20 == i || 11 == i)
48 && (18 == o || 17 == o || 16 == o || 15 == o || 14 == o || 13 == o)))
49 return -EINVAL;
50
51 /* to understand this, have a look at the tea6415c-specs (p.5) */
52 switch (o) {
53 case 18:
54 byte = 0x00;
55 break;
56 case 14:
57 byte = 0x20;
58 break;
59 case 16:
60 byte = 0x10;
61 break;
62 case 17:
63 byte = 0x08;
64 break;
65 case 15:
66 byte = 0x18;
67 break;
68 case 13:
69 byte = 0x28;
70 break;
71 }
72
73 switch (i) {
74 case 5:
75 byte |= 0x00;
76 break;
77 case 8:
78 byte |= 0x04;
79 break;
80 case 3:
81 byte |= 0x02;
82 break;
83 case 20:
84 byte |= 0x06;
85 break;
86 case 6:
87 byte |= 0x01;
88 break;
89 case 10:
90 byte |= 0x05;
91 break;
92 case 1:
93 byte |= 0x03;
94 break;
95 case 11:
96 byte |= 0x07;
97 break;
98 }
99
100 ret = i2c_smbus_write_byte(client, value: byte);
101 if (ret) {
102 v4l2_dbg(1, debug, sd,
103 "i2c_smbus_write_byte() failed, ret:%d\n", ret);
104 return -EIO;
105 }
106 return ret;
107}
108
109/* ----------------------------------------------------------------------- */
110
111static const struct v4l2_subdev_video_ops tea6415c_video_ops = {
112 .s_routing = tea6415c_s_routing,
113};
114
115static const struct v4l2_subdev_ops tea6415c_ops = {
116 .video = &tea6415c_video_ops,
117};
118
119static int tea6415c_probe(struct i2c_client *client)
120{
121 struct v4l2_subdev *sd;
122
123 /* let's see whether this adapter can support what we need */
124 if (!i2c_check_functionality(adap: client->adapter, I2C_FUNC_SMBUS_WRITE_BYTE))
125 return -EIO;
126
127 v4l_info(client, "chip found @ 0x%x (%s)\n",
128 client->addr << 1, client->adapter->name);
129 sd = devm_kzalloc(dev: &client->dev, size: sizeof(*sd), GFP_KERNEL);
130 if (sd == NULL)
131 return -ENOMEM;
132 v4l2_i2c_subdev_init(sd, client, ops: &tea6415c_ops);
133 return 0;
134}
135
136static void tea6415c_remove(struct i2c_client *client)
137{
138 struct v4l2_subdev *sd = i2c_get_clientdata(client);
139
140 v4l2_device_unregister_subdev(sd);
141}
142
143static const struct i2c_device_id tea6415c_id[] = {
144 { "tea6415c", 0 },
145 { }
146};
147MODULE_DEVICE_TABLE(i2c, tea6415c_id);
148
149static struct i2c_driver tea6415c_driver = {
150 .driver = {
151 .name = "tea6415c",
152 },
153 .probe = tea6415c_probe,
154 .remove = tea6415c_remove,
155 .id_table = tea6415c_id,
156};
157
158module_i2c_driver(tea6415c_driver);
159

source code of linux/drivers/media/i2c/tea6415c.c