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
  24 struct 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
  37 static struct v4l2_i2c_driver_data v4l2_i2c_data;
  38 static const struct i2c_client_address_data addr_data;
  39 static struct i2c_driver v4l2_i2c_driver_legacy;
  40 static char v4l2_i2c_drv_name_legacy[32];
  41
  42 static 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
  48 static 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
  60 static 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
  74 static 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
  79 static 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 */
  87 static 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 */
 100 static struct i2c_driver v4l2_i2c_driver = {
 101         .suspend        = v4l2_i2c_drv_suspend_helper,
 102         .resume         = v4l2_i2c_drv_resume_helper,
 103 };
 104
 105 static 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
 134 static 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
 140 module_init(v4l2_i2c_drv_init);
 141 module_exit(v4l2_i2c_drv_cleanup);