LXR linux/include/media/v4l2-i2c-drv-legacy.h

   1/*
   2 * v4l2-i2c-drv-legacy.h - contains I2C handling code that's identical
   3 *                  for all V4L2 I2C drivers. Use this header if the
   4 *                  I2C driver is used by both legacy drivers and
   5 *                  drivers converted to the bus-based I2C API.
   6 *
   7 * Copyright (C) 2007 Hans Verkuil <hverkuil@xs4all.nl>
   8 *
   9 * This program is free software; you can redistribute it and/or modify
  10 * it under the terms of the GNU General Public License as published by
  11 * the Free Software Foundation; either version 2 of the License, or
  12 * (at your option) any later version.
  13 *
  14 * This program is distributed in the hope that it will be useful,
  15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17 * GNU General Public License for more details.
  18 *
  19 * You should have received a copy of the GNU General Public License
  20 * along with this program; if not, write to the Free Software
  21 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  22 */
  23
  24struct v4l2_i2c_driver_data {
  25        const char * const name;
  26        int driverid;
  27        int (*command)(struct i2c_client *client, unsigned int cmd, void *arg);
  28        int (*probe)(struct i2c_client *client, const struct i2c_device_id *id);
  29        int (*remove)(struct i2c_client *client);
  30        int (*suspend)(struct i2c_client *client, pm_message_t state);
  31        int (*resume)(struct i2c_client *client);
  32        int (*legacy_probe)(struct i2c_adapter *adapter);
  33        int legacy_class;
  34        const struct i2c_device_id *id_table;
  35};
  36
  37static struct v4l2_i2c_driver_data v4l2_i2c_data;
  38static const struct i2c_client_address_data addr_data;
  39static struct i2c_driver v4l2_i2c_driver_legacy;
  40static char v4l2_i2c_drv_name_legacy[32];
  41
  42static int v4l2_i2c_drv_attach_legacy(struct i2c_adapter *adapter, int address, int kind)
  43{
  44        return v4l2_i2c_attach(adapter, address, &v4l2_i2c_driver_legacy,
  45                        v4l2_i2c_drv_name_legacy, v4l2_i2c_data.probe);
  46}
  47
  48static int v4l2_i2c_drv_probe_legacy(struct i2c_adapter *adapter)
  49{
  50        if (v4l2_i2c_data.legacy_probe) {
  51                if (v4l2_i2c_data.legacy_probe(adapter))
  52                        return i2c_probe(adapter, &addr_data, v4l2_i2c_drv_attach_legacy);
  53                return 0;
  54        }
  55        if (adapter->class & v4l2_i2c_data.legacy_class)
  56                return i2c_probe(adapter, &addr_data, v4l2_i2c_drv_attach_legacy);
  57        return 0;
  58}
  59
  60static int v4l2_i2c_drv_detach_legacy(struct i2c_client *client)
  61{
  62        int err;
  63
  64        if (v4l2_i2c_data.remove)
  65                v4l2_i2c_data.remove(client);
  66
  67        err = i2c_detach_client(client);
  68        if (err)
  69                return err;
  70        kfree(client);
  71        return 0;
  72}
  73
  74static int v4l2_i2c_drv_suspend_helper(struct i2c_client *client, pm_message_t state)
  75{
  76        return v4l2_i2c_data.suspend ? v4l2_i2c_data.suspend(client, state) : 0;
  77}
  78
  79static int v4l2_i2c_drv_resume_helper(struct i2c_client *client)
  80{
  81        return v4l2_i2c_data.resume ? v4l2_i2c_data.resume(client) : 0;
  82}
  83
  84/* ----------------------------------------------------------------------- */
  85
  86/* i2c implementation */
  87static struct i2c_driver v4l2_i2c_driver_legacy = {
  88        .driver = {
  89                .owner = THIS_MODULE,
  90        },
  91        .attach_adapter = v4l2_i2c_drv_probe_legacy,
  92        .detach_client = v4l2_i2c_drv_detach_legacy,
  93        .suspend = v4l2_i2c_drv_suspend_helper,
  94        .resume  = v4l2_i2c_drv_resume_helper,
  95};
  96
  97/* ----------------------------------------------------------------------- */
  98
  99/* i2c implementation */
 100static struct i2c_driver v4l2_i2c_driver = {
 101        .suspend        = v4l2_i2c_drv_suspend_helper,
 102        .resume         = v4l2_i2c_drv_resume_helper,
 103};
 104
 105static int __init v4l2_i2c_drv_init(void)
 106{
 107        int err;
 108
 109        strlcpy(v4l2_i2c_drv_name_legacy, v4l2_i2c_data.name, sizeof(v4l2_i2c_drv_name_legacy));
 110        strlcat(v4l2_i2c_drv_name_legacy, "'", sizeof(v4l2_i2c_drv_name_legacy));
 111
 112        if (v4l2_i2c_data.legacy_class == 0)
 113                v4l2_i2c_data.legacy_class = I2C_CLASS_TV_ANALOG;
 114
 115        v4l2_i2c_driver_legacy.driver.name = v4l2_i2c_drv_name_legacy;
 116        v4l2_i2c_driver_legacy.id = v4l2_i2c_data.driverid;
 117        v4l2_i2c_driver_legacy.command = v4l2_i2c_data.command;
 118        err = i2c_add_driver(&v4l2_i2c_driver_legacy);
 119
 120        if (err)
 121                return err;
 122        v4l2_i2c_driver.driver.name = v4l2_i2c_data.name;
 123        v4l2_i2c_driver.id = v4l2_i2c_data.driverid;
 124        v4l2_i2c_driver.command = v4l2_i2c_data.command;
 125        v4l2_i2c_driver.probe = v4l2_i2c_data.probe;
 126        v4l2_i2c_driver.remove = v4l2_i2c_data.remove;
 127        v4l2_i2c_driver.id_table = v4l2_i2c_data.id_table;
 128        err = i2c_add_driver(&v4l2_i2c_driver);
 129        if (err)
 130                i2c_del_driver(&v4l2_i2c_driver_legacy);
 131        return err;
 132}
 133
 134static void __exit v4l2_i2c_drv_cleanup(void)
 135{
 136        i2c_del_driver(&v4l2_i2c_driver_legacy);
 137        i2c_del_driver(&v4l2_i2c_driver);
 138}
 139
 140module_init(v4l2_i2c_drv_init);
 141module_exit(v4l2_i2c_drv_cleanup);
 142