kernel/device.c

   1 /* kernel/device.c
   2  *
   3  * Copyright (C) 2007 David Cohen <dacohen@gmail.com>
   4  * Copyright (C) 2007 Felipe Balbi <me@felipebalbi.com>
   5  *
   6  * This file is part of Tinyx Nanokernel Project.
   7  *
   8  * Tinyx is free software: you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation, either version 3 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * Tinyx is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with Tinyx.  If not, see <http://www.gnu.org/licenses/>.
  20  */
  21
  22 #include <tinyx/device.h>
  23 #include <tinyx/list.h>
  24 #include <string.h>
  25
  26 DECLARE_LIST_HEAD(bus_list);
  27 DECLARE_LIST_HEAD(driver_list);
  28 DECLARE_LIST_HEAD(device_list);
  29
  30 static void *match_device_driver(struct device *dev, struct device_driver *drv)
  31 {
  32         struct list_head *list;
  33         struct list_head *entry;
  34         void *item;
  35         int ret;
  36
  37         if (!dev)
  38                 list = &device_list;
  39         else
  40                 list = &driver_list;
  41
  42         list_for_each(list, entry) {
  43                 if (!dev) {
  44                         item = list_entry(entry, struct device, queue);
  45                         ret = strcmp(((struct device *)item)->name, drv->name);
  46                 } else {
  47                         item = list_entry(entry, struct device_driver, queue);
  48                         ret = strcmp(dev->name,
  49                                         ((struct device_driver *)item)->name);
  50                 }
  51                 if (!ret)
  52                         break;
  53                 else
  54                         item = NULL;
  55         }
  56
  57         return item;
  58 }
  59
  60 int register_bus_type(struct bus_type *bus)
  61 {
  62         int ret = 0;
  63
  64         if (bus == NULL)
  65                 return -ENODEV;
  66
  67         if (bus->probe)
  68                 ret = bus->probe(bus);
  69         if (!ret)
  70                 list_add_tail(&bus_list, &bus->queue);
  71
  72         return ret;
  73 }
  74
  75 int register_device_driver(struct device_driver *drv)
  76 {
  77         int ret = 0;
  78         struct device *dev;
  79
  80         if (drv == NULL)
  81                 return -ENODEV;
  82
  83         dev = match_device_driver(NULL, drv);
  84         if (dev) {
  85                 if (dev->bus->match)
  86                         ret = dev->bus->match(dev->bus, dev, drv);
  87                 if (!ret && drv->probe)
  88                         ret = drv->probe(dev);
  89         }
  90
  91         if (!ret)
  92                 list_add_tail(&driver_list, &drv->queue);
  93
  94         return ret;
  95 }
  96
  97 int register_device(struct device *dev, struct bus_type *bus)
  98 {
  99         int ret = 0;
 100         struct device_driver *drv;
 101
 102         if (dev == NULL)
 103                 return -ENODEV;
 104
 105         dev->bus = bus;
 106         drv = match_device_driver(dev, NULL);
 107         if (drv) {
 108                 if (bus->match)
 109                         ret = bus->match(bus, dev, drv);
 110                 if (!ret && drv->probe)
 111                         ret = drv->probe(dev);
 112         }
 113
 114         if (!ret)
 115                 list_add_tail(&device_list, &dev->queue);
 116         else
 117                 dev->bus = NULL;
 118
 119         return ret;
 120 }