xref: /openbmc/linux/drivers/media/i2c/tea6415c.c (revision 1edd0337)
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' */
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 
119 static 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(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(&client->dev, sizeof(*sd), GFP_KERNEL);
130 	if (sd == NULL)
131 		return -ENOMEM;
132 	v4l2_i2c_subdev_init(sd, client, &tea6415c_ops);
133 	return 0;
134 }
135 
136 static 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 
143 static const struct i2c_device_id tea6415c_id[] = {
144 	{ "tea6415c", 0 },
145 	{ }
146 };
147 MODULE_DEVICE_TABLE(i2c, tea6415c_id);
148 
149 static struct i2c_driver tea6415c_driver = {
150 	.driver = {
151 		.name	= "tea6415c",
152 	},
153 	.probe_new	= tea6415c_probe,
154 	.remove		= tea6415c_remove,
155 	.id_table	= tea6415c_id,
156 };
157 
158 module_i2c_driver(tea6415c_driver);
159