drivers/media/i2c/tea6415c.c

   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 "tea6415c.h"
  37
  38 MODULE_AUTHOR("Michael Hunold <michael@mihu.de>");
  39 MODULE_DESCRIPTION("tea6415c driver");
  40 MODULE_LICENSE("GPL");
  41
  42 static int debug;
  43 module_param(debug, int, 0644);
  44
  45 MODULE_PARM_DESC(debug, "Debug level (0-1)");
  46
  47
  48 /* makes a connection between the input-pin 'i' and the output-pin 'o' */
  49 static int tea6415c_s_routing(struct v4l2_subdev *sd,
  50                               u32 i, u32 o, u32 config)
  51 {
  52         struct i2c_client *client = v4l2_get_subdevdata(sd);
  53         u8 byte = 0;
  54         int ret;
  55
  56         v4l2_dbg(1, debug, sd, "i=%d, o=%d\n", i, o);
  57
  58         /* check if the pins are valid */
  59         if (0 == ((1 == i ||  3 == i ||  5 == i ||  6 == i ||  8 == i || 10 == i || 20 == i || 11 == i)
  60               && (18 == o || 17 == o || 16 == o || 15 == o || 14 == o || 13 == o)))
  61                 return -EINVAL;
  62
  63         /* to understand this, have a look at the tea6415c-specs (p.5) */
  64         switch (o) {
  65         case 18:
  66                 byte = 0x00;
  67                 break;
  68         case 14:
  69                 byte = 0x20;
  70                 break;
  71         case 16:
  72                 byte = 0x10;
  73                 break;
  74         case 17:
  75                 byte = 0x08;
  76                 break;
  77         case 15:
  78                 byte = 0x18;
  79                 break;
  80         case 13:
  81                 byte = 0x28;
  82                 break;
  83         }
  84
  85         switch (i) {
  86         case 5:
  87                 byte |= 0x00;
  88                 break;
  89         case 8:
  90                 byte |= 0x04;
  91                 break;
  92         case 3:
  93                 byte |= 0x02;
  94                 break;
  95         case 20:
  96                 byte |= 0x06;
  97                 break;
  98         case 6:
  99                 byte |= 0x01;
 100                 break;
 101         case 10:
 102                 byte |= 0x05;
 103                 break;
 104         case 1:
 105                 byte |= 0x03;
 106                 break;
 107         case 11:
 108                 byte |= 0x07;
 109                 break;
 110         }
 111
 112         ret = i2c_smbus_write_byte(client, byte);
 113         if (ret) {
 114                 v4l2_dbg(1, debug, sd,
 115                         "i2c_smbus_write_byte() failed, ret:%d\n", ret);
 116                 return -EIO;
 117         }
 118         return ret;
 119 }
 120
 121 /* ----------------------------------------------------------------------- */
 122
 123 static const struct v4l2_subdev_video_ops tea6415c_video_ops = {
 124         .s_routing = tea6415c_s_routing,
 125 };
 126
 127 static const struct v4l2_subdev_ops tea6415c_ops = {
 128         .video = &tea6415c_video_ops,
 129 };
 130
 131 static int tea6415c_probe(struct i2c_client *client,
 132                           const struct i2c_device_id *id)
 133 {
 134         struct v4l2_subdev *sd;
 135
 136         /* let's see whether this adapter can support what we need */
 137         if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WRITE_BYTE))
 138                 return -EIO;
 139
 140         v4l_info(client, "chip found @ 0x%x (%s)\n",
 141                         client->addr << 1, client->adapter->name);
 142         sd = devm_kzalloc(&client->dev, sizeof(*sd), GFP_KERNEL);
 143         if (sd == NULL)
 144                 return -ENOMEM;
 145         v4l2_i2c_subdev_init(sd, client, &tea6415c_ops);
 146         return 0;
 147 }
 148
 149 static int tea6415c_remove(struct i2c_client *client)
 150 {
 151         struct v4l2_subdev *sd = i2c_get_clientdata(client);
 152
 153         v4l2_device_unregister_subdev(sd);
 154         return 0;
 155 }
 156
 157 static const struct i2c_device_id tea6415c_id[] = {
 158         { "tea6415c", 0 },
 159         { }
 160 };
 161 MODULE_DEVICE_TABLE(i2c, tea6415c_id);
 162
 163 static struct i2c_driver tea6415c_driver = {
 164         .driver = {
 165                 .name   = "tea6415c",
 166         },
 167         .probe          = tea6415c_probe,
 168         .remove         = tea6415c_remove,
 169         .id_table       = tea6415c_id,
 170 };
 171
 172 module_i2c_driver(tea6415c_driver);