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
26 MODULE_AUTHOR("Michael Hunold <michael@mihu.de>");
27 MODULE_DESCRIPTION("tea6415c driver");
28 MODULE_LICENSE("GPL");
29
30 static int debug;
31 module_param(debug, int, 0644);
32
33 MODULE_PARM_DESC(debug, "Debug level (0-1)");
34
35
36 /* makes a connection between the input-pin 'i' and the output-pin 'o' */
tea6415c_s_routing(struct v4l2_subdev * sd,u32 i,u32 o,u32 config)37 static 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, 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
111 static const struct v4l2_subdev_video_ops tea6415c_video_ops = {
112 .s_routing = tea6415c_s_routing,
113 };
114
115 static const struct v4l2_subdev_ops tea6415c_ops = {
116 .video = &tea6415c_video_ops,
117 };
118
tea6415c_probe(struct i2c_client * client,const struct i2c_device_id * id)119 static int tea6415c_probe(struct i2c_client *client,
120 const struct i2c_device_id *id)
121 {
122 struct v4l2_subdev *sd;
123
124 /* let's see whether this adapter can support what we need */
125 if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WRITE_BYTE))
126 return -EIO;
127
128 v4l_info(client, "chip found @ 0x%x (%s)\n",
129 client->addr << 1, client->adapter->name);
130 sd = devm_kzalloc(&client->dev, sizeof(*sd), GFP_KERNEL);
131 if (sd == NULL)
132 return -ENOMEM;
133 v4l2_i2c_subdev_init(sd, client, &tea6415c_ops);
134 return 0;
135 }
136
tea6415c_remove(struct i2c_client * client)137 static int tea6415c_remove(struct i2c_client *client)
138 {
139 struct v4l2_subdev *sd = i2c_get_clientdata(client);
140
141 v4l2_device_unregister_subdev(sd);
142 return 0;
143 }
144
145 static const struct i2c_device_id tea6415c_id[] = {
146 { "tea6415c", 0 },
147 { }
148 };
149 MODULE_DEVICE_TABLE(i2c, tea6415c_id);
150
151 static struct i2c_driver tea6415c_driver = {
152 .driver = {
153 .name = "tea6415c",
154 },
155 .probe = tea6415c_probe,
156 .remove = tea6415c_remove,
157 .id_table = tea6415c_id,
158 };
159
160 module_i2c_driver(tea6415c_driver);
161