media/i2c/tea6415c.c

0001 // SPDX-License-Identifier: GPL-2.0-or-later
0002  /*
0003     tea6415c - i2c-driver for the tea6415c by SGS Thomson
0004
0005     Copyright (C) 1998-2003 Michael Hunold <michael@mihu.de>
0006     Copyright (C) 2008 Hans Verkuil <hverkuil@xs4all.nl>
0007
0008     The tea6415c is a bus controlled video-matrix-switch
0009     with 8 inputs and 6 outputs.
0010     It is cascadable, i.e. it can be found at the addresses
0011     0x86 and 0x06 on the i2c-bus.
0012
0013     For detailed information download the specifications directly
0014     from SGS Thomson at http://www.st.com
0015
0016   */
0017
0018
0019 #include <linux/module.h>
0020 #include <linux/ioctl.h>
0021 #include <linux/slab.h>
0022 #include <linux/i2c.h>
0023 #include <media/v4l2-device.h>
0024 #include "tea6415c.h"
0025
0026 MODULE_AUTHOR("Michael Hunold <michael@mihu.de>");
0027 MODULE_DESCRIPTION("tea6415c driver");
0028 MODULE_LICENSE("GPL");
0029
0030 static int debug;
0031 module_param(debug, int, 0644);
0032
0033 MODULE_PARM_DESC(debug, "Debug level (0-1)");
0034
0035
0036 /* makes a connection between the input-pin 'i' and the output-pin 'o' */
0037 static int tea6415c_s_routing(struct v4l2_subdev *sd,
0038                   u32 i, u32 o, u32 config)
0039 {
0040     struct i2c_client *client = v4l2_get_subdevdata(sd);
0041     u8 byte = 0;
0042     int ret;
0043
0044     v4l2_dbg(1, debug, sd, "i=%d, o=%d\n", i, o);
0045
0046     /* check if the pins are valid */
0047     if (0 == ((1 == i ||  3 == i ||  5 == i ||  6 == i ||  8 == i || 10 == i || 20 == i || 11 == i)
0048           && (18 == o || 17 == o || 16 == o || 15 == o || 14 == o || 13 == o)))
0049         return -EINVAL;
0050
0051     /* to understand this, have a look at the tea6415c-specs (p.5) */
0052     switch (o) {
0053     case 18:
0054         byte = 0x00;
0055         break;
0056     case 14:
0057         byte = 0x20;
0058         break;
0059     case 16:
0060         byte = 0x10;
0061         break;
0062     case 17:
0063         byte = 0x08;
0064         break;
0065     case 15:
0066         byte = 0x18;
0067         break;
0068     case 13:
0069         byte = 0x28;
0070         break;
0071     }
0072
0073     switch (i) {
0074     case 5:
0075         byte |= 0x00;
0076         break;
0077     case 8:
0078         byte |= 0x04;
0079         break;
0080     case 3:
0081         byte |= 0x02;
0082         break;
0083     case 20:
0084         byte |= 0x06;
0085         break;
0086     case 6:
0087         byte |= 0x01;
0088         break;
0089     case 10:
0090         byte |= 0x05;
0091         break;
0092     case 1:
0093         byte |= 0x03;
0094         break;
0095     case 11:
0096         byte |= 0x07;
0097         break;
0098     }
0099
0100     ret = i2c_smbus_write_byte(client, byte);
0101     if (ret) {
0102         v4l2_dbg(1, debug, sd,
0103             "i2c_smbus_write_byte() failed, ret:%d\n", ret);
0104         return -EIO;
0105     }
0106     return ret;
0107 }
0108
0109 /* ----------------------------------------------------------------------- */
0110
0111 static const struct v4l2_subdev_video_ops tea6415c_video_ops = {
0112     .s_routing = tea6415c_s_routing,
0113 };
0114
0115 static const struct v4l2_subdev_ops tea6415c_ops = {
0116     .video = &tea6415c_video_ops,
0117 };
0118
0119 static int tea6415c_probe(struct i2c_client *client,
0120               const struct i2c_device_id *id)
0121 {
0122     struct v4l2_subdev *sd;
0123
0124     /* let's see whether this adapter can support what we need */
0125     if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WRITE_BYTE))
0126         return -EIO;
0127
0128     v4l_info(client, "chip found @ 0x%x (%s)\n",
0129             client->addr << 1, client->adapter->name);
0130     sd = devm_kzalloc(&client->dev, sizeof(*sd), GFP_KERNEL);
0131     if (sd == NULL)
0132         return -ENOMEM;
0133     v4l2_i2c_subdev_init(sd, client, &tea6415c_ops);
0134     return 0;
0135 }
0136
0137 static int tea6415c_remove(struct i2c_client *client)
0138 {
0139     struct v4l2_subdev *sd = i2c_get_clientdata(client);
0140
0141     v4l2_device_unregister_subdev(sd);
0142     return 0;
0143 }
0144
0145 static const struct i2c_device_id tea6415c_id[] = {
0146     { "tea6415c", 0 },
0147     { }
0148 };
0149 MODULE_DEVICE_TABLE(i2c, tea6415c_id);
0150
0151 static struct i2c_driver tea6415c_driver = {
0152     .driver = {
0153         .name   = "tea6415c",
0154     },
0155     .probe      = tea6415c_probe,
0156     .remove     = tea6415c_remove,
0157     .id_table   = tea6415c_id,
0158 };
0159
0160 module_i2c_driver(tea6415c_driver);