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 <media/v4l2-chip-ident.h>
  37#include "tea6415c.h"
  38
  39MODULE_AUTHOR("Michael Hunold <michael@mihu.de>");
  40MODULE_DESCRIPTION("tea6415c driver");
  41MODULE_LICENSE("GPL");
  42
  43static int debug;
  44module_param(debug, int, 0644);
  45
  46MODULE_PARM_DESC(debug, "Debug level (0-1)");
  47
  48
  49/* makes a connection between the input-pin 'i' and the output-pin 'o' */
  50static 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
 122static 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
 131static const struct v4l2_subdev_core_ops tea6415c_core_ops = {
 132        .g_chip_ident = tea6415c_g_chip_ident,
 133};
 134
 135static const struct v4l2_subdev_video_ops tea6415c_video_ops = {
 136        .s_routing = tea6415c_s_routing,
 137};
 138
 139static const struct v4l2_subdev_ops tea6415c_ops = {
 140        .core = &tea6415c_core_ops,
 141        .video = &tea6415c_video_ops,
 142};
 143
 144static 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
 162static 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
 171static const struct i2c_device_id tea6415c_id[] = {
 172        { "tea6415c", 0 },
 173        { }
 174};
 175MODULE_DEVICE_TABLE(i2c, tea6415c_id);
 176
 177static 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
 187module_i2c_driver(tea6415c_driver);
 188