drivers/uwb/pal.c

   1 /*
   2  * UWB PAL support.
   3  *
   4  * Copyright (C) 2008 Cambridge Silicon Radio Ltd.
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License version
   8  * 2 as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17  */
  18 #include <linux/kernel.h>
  19 #include <linux/uwb.h>
  20
  21 #include "uwb-internal.h"
  22
  23 /**
  24  * uwb_pal_init - initialize a UWB PAL
  25  * @pal: the PAL to initialize
  26  */
  27 void uwb_pal_init(struct uwb_pal *pal)
  28 {
  29         INIT_LIST_HEAD(&pal->node);
  30 }
  31 EXPORT_SYMBOL_GPL(uwb_pal_init);
  32
  33 /**
  34  * uwb_pal_register - register a UWB PAL
  35  * @rc: the radio controller the PAL will be using
  36  * @pal: the PAL
  37  *
  38  * The PAL must be initialized with uwb_pal_init().
  39  */
  40 int uwb_pal_register(struct uwb_rc *rc, struct uwb_pal *pal)
  41 {
  42         int ret;
  43
  44         if (pal->device) {
  45                 ret = sysfs_create_link(&pal->device->kobj,
  46                                         &rc->uwb_dev.dev.kobj, "uwb_rc");
  47                 if (ret < 0)
  48                         return ret;
  49                 ret = sysfs_create_link(&rc->uwb_dev.dev.kobj,
  50                                         &pal->device->kobj, pal->name);
  51                 if (ret < 0) {
  52                         sysfs_remove_link(&pal->device->kobj, "uwb_rc");
  53                         return ret;
  54                 }
  55         }
  56
  57         spin_lock(&rc->pal_lock);
  58         list_add(&pal->node, &rc->pals);
  59         spin_unlock(&rc->pal_lock);
  60
  61         return 0;
  62 }
  63 EXPORT_SYMBOL_GPL(uwb_pal_register);
  64
  65 /**
  66  * uwb_pal_register - unregister a UWB PAL
  67  * @rc: the radio controller the PAL was using
  68  * @pal: the PAL
  69  */
  70 void uwb_pal_unregister(struct uwb_rc *rc, struct uwb_pal *pal)
  71 {
  72         spin_lock(&rc->pal_lock);
  73         list_del(&pal->node);
  74         spin_unlock(&rc->pal_lock);
  75
  76         if (pal->device) {
  77                 sysfs_remove_link(&rc->uwb_dev.dev.kobj, pal->name);
  78                 sysfs_remove_link(&pal->device->kobj, "uwb_rc");
  79         }
  80 }
  81 EXPORT_SYMBOL_GPL(uwb_pal_unregister);
  82
  83 /**
  84  * uwb_rc_pal_init - initialize the PAL related parts of a radio controller
  85  * @rc: the radio controller
  86  */
  87 void uwb_rc_pal_init(struct uwb_rc *rc)
  88 {
  89         spin_lock_init(&rc->pal_lock);
  90         INIT_LIST_HEAD(&rc->pals);
  91 }