LXR linux/drivers/dio/dio-driver.c

   1/*
   2 *  DIO Driver Services
   3 *
   4 *  Copyright (C) 2004 Jochen Friedrich
   5 *
   6 *  Loosely based on drivers/pci/pci-driver.c and drivers/zorro/zorro-driver.c
   7 *
   8 *  This file is subject to the terms and conditions of the GNU General Public
   9 *  License.  See the file COPYING in the main directory of this archive
  10 *  for more details.
  11 */
  12
  13#include <linux/init.h>
  14#include <linux/module.h>
  15#include <linux/dio.h>
  16
  17
  18/**
  19 *  dio_match_device - Tell if a DIO device structure has a matching DIO device id structure
  20 *  @ids: array of DIO device id structures to search in
  21 *  @d: the DIO device structure to match against
  22 *
  23 *  Used by a driver to check whether a DIO device present in the
  24 *  system is in its list of supported devices. Returns the matching
  25 *  dio_device_id structure or %NULL if there is no match.
  26 */
  27
  28const struct dio_device_id *
  29dio_match_device(const struct dio_device_id *ids,
  30                   const struct dio_dev *d)
  31{
  32        while (ids->id) {
  33                if (ids->id == DIO_WILDCARD)
  34                        return ids;
  35                if (DIO_NEEDSSECID(ids->id & 0xff)) {
  36                        if (ids->id == d->id)
  37                                return ids;
  38                } else {
  39                        if ((ids->id & 0xff) == (d->id & 0xff))
  40                                return ids;
  41                }
  42                ids++;
  43        }
  44        return NULL;
  45}
  46
  47static int dio_device_probe(struct device *dev)
  48{
  49        int error = 0;
  50        struct dio_driver *drv = to_dio_driver(dev->driver);
  51        struct dio_dev *d = to_dio_dev(dev);
  52
  53        if (!d->driver && drv->probe) {
  54                const struct dio_device_id *id;
  55
  56                id = dio_match_device(drv->id_table, d);
  57                if (id)
  58                        error = drv->probe(d, id);
  59                if (error >= 0) {
  60                        d->driver = drv;
  61                        error = 0;
  62                }
  63        }
  64        return error;
  65}
  66
  67
  68/**
  69 *  dio_register_driver - register a new DIO driver
  70 *  @drv: the driver structure to register
  71 *
  72 *  Adds the driver structure to the list of registered drivers
  73 *  Returns zero or a negative error value.
  74 */
  75
  76int dio_register_driver(struct dio_driver *drv)
  77{
  78        /* initialize common driver fields */
  79        drv->driver.name = drv->name;
  80        drv->driver.bus = &dio_bus_type;
  81
  82        /* register with core */
  83        return driver_register(&drv->driver);
  84}
  85
  86
  87/**
  88 *  dio_unregister_driver - unregister a DIO driver
  89 *  @drv: the driver structure to unregister
  90 *
  91 *  Deletes the driver structure from the list of registered DIO drivers,
  92 *  gives it a chance to clean up by calling its remove() function for
  93 *  each device it was responsible for, and marks those devices as
  94 *  driverless.
  95 */
  96
  97void dio_unregister_driver(struct dio_driver *drv)
  98{
  99        driver_unregister(&drv->driver);
 100}
 101
 102
 103/**
 104 *  dio_bus_match - Tell if a DIO device structure has a matching DIO device id structure
 105 *  @dev: the DIO device structure to match against
 106 *  @drv: the &device_driver that points to the array of DIO device id structures to search
 107 *
 108 *  Used by a driver to check whether a DIO device present in the
 109 *  system is in its list of supported devices. Returns the matching
 110 *  dio_device_id structure or %NULL if there is no match.
 111 */
 112
 113static int dio_bus_match(struct device *dev, struct device_driver *drv)
 114{
 115        struct dio_dev *d = to_dio_dev(dev);
 116        struct dio_driver *dio_drv = to_dio_driver(drv);
 117        const struct dio_device_id *ids = dio_drv->id_table;
 118
 119        if (!ids)
 120                return 0;
 121
 122        return dio_match_device(ids, d) ? 1 : 0;
 123}
 124
 125
 126struct bus_type dio_bus_type = {
 127        .name   = "dio",
 128        .match  = dio_bus_match,
 129        .probe  = dio_device_probe,
 130};
 131
 132
 133static int __init dio_driver_init(void)
 134{
 135        return bus_register(&dio_bus_type);
 136}
 137
 138postcore_initcall(dio_driver_init);
 139
 140EXPORT_SYMBOL(dio_match_device);
 141EXPORT_SYMBOL(dio_register_driver);
 142EXPORT_SYMBOL(dio_unregister_driver);
 143EXPORT_SYMBOL(dio_bus_type);
 144