LXR linux/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
  38MODULE_AUTHOR("Michael Hunold <michael@mihu.de>");
  39MODULE_DESCRIPTION("tea6415c driver");
  40MODULE_LICENSE("GPL");
  41
  42static int debug;
  43module_param(debug, int, 0644);
  44
  45MODULE_PARM_DESC(debug, "Debug level (0-1)");
  46
  47
  48/* makes a connection between the input-pin 'i' and the output-pin 'o' */
  49static 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
 123static const struct v4l2_subdev_video_ops tea6415c_video_ops = {
 124        .s_routing = tea6415c_s_routing,
 125};
 126
 127static const struct v4l2_subdev_ops tea6415c_ops = {
 128        .video = &tea6415c_video_ops,
 129};
 130
 131static 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
 149static 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
 157static const struct i2c_device_id tea6415c_id[] = {
 158        { "tea6415c", 0 },
 159        { }
 160};
 161MODULE_DEVICE_TABLE(i2c, tea6415c_id);
 162
 163static 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
 172module_i2c_driver(tea6415c_driver);
 173