drivers/media/i2c/tea6415c.c

   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                           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
 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);