xref: /openbmc/linux/drivers/media/i2c/tea6415c.c (revision 8fdff1dc)
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 
39 MODULE_AUTHOR("Michael Hunold <michael@mihu.de>");
40 MODULE_DESCRIPTION("tea6415c driver");
41 MODULE_LICENSE("GPL");
42 
43 static int debug;
44 module_param(debug, int, 0644);
45 
46 MODULE_PARM_DESC(debug, "Debug level (0-1)");
47 
48 
49 /* makes a connection between the input-pin 'i' and the output-pin 'o' */
50 static 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 
122 static 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 
131 static const struct v4l2_subdev_core_ops tea6415c_core_ops = {
132 	.g_chip_ident = tea6415c_g_chip_ident,
133 };
134 
135 static const struct v4l2_subdev_video_ops tea6415c_video_ops = {
136 	.s_routing = tea6415c_s_routing,
137 };
138 
139 static const struct v4l2_subdev_ops tea6415c_ops = {
140 	.core = &tea6415c_core_ops,
141 	.video = &tea6415c_video_ops,
142 };
143 
144 static 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 
162 static 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 
171 static const struct i2c_device_id tea6415c_id[] = {
172 	{ "tea6415c", 0 },
173 	{ }
174 };
175 MODULE_DEVICE_TABLE(i2c, tea6415c_id);
176 
177 static 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 
187 module_i2c_driver(tea6415c_driver);
188