drivers/staging/meilhaus/meslist.c

   1 /**
   2  * @file me_slist.c
   3  *
   4  * @brief Implements the subdevice list class.
   5  * @note Copyright (C) 2007 Meilhaus Electronic GmbH (support@meilhaus.de)
   6  * @author Guenter Gebhardt
   7  */
   8
   9 /*
  10  * Copyright (C) 2007 Meilhaus Electronic GmbH (support@meilhaus.de)
  11  *
  12  * This file is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License as published by
  14  * the Free Software Foundation; either version 2 of the License, or
  15  * (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License
  23  * along with this program; if not, write to the Free Software
  24  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  25  */
  26
  27 #include "meerror.h"
  28 #include "medefines.h"
  29
  30 #include "meslist.h"
  31 #include "medebug.h"
  32
  33 int me_slist_query_number_subdevices(struct me_slist *slist, int *number)
  34 {
  35         PDEBUG_LOCKS("called.\n");
  36         *number = slist->n;
  37         return ME_ERRNO_SUCCESS;
  38 }
  39
  40 unsigned int me_slist_get_number_subdevices(struct me_slist *slist)
  41 {
  42         PDEBUG_LOCKS("called.\n");
  43         return slist->n;
  44 }
  45
  46 me_subdevice_t *me_slist_get_subdevice(struct me_slist * slist,
  47                                        unsigned int index)
  48 {
  49
  50         struct list_head *pos;
  51         me_subdevice_t *subdevice = NULL;
  52         unsigned int i = 0;
  53
  54         PDEBUG_LOCKS("called.\n");
  55
  56         if (index >= slist->n) {
  57                 PERROR("Index out of range.\n");
  58                 return NULL;
  59         }
  60
  61         list_for_each(pos, &slist->head) {
  62                 if (i == index) {
  63                         subdevice = list_entry(pos, me_subdevice_t, list);
  64                         break;
  65                 }
  66
  67                 ++i;
  68         }
  69
  70         return subdevice;
  71 }
  72
  73 int me_slist_get_subdevice_by_type(struct me_slist *slist,
  74                                    unsigned int start_subdevice,
  75                                    int type, int subtype, int *subdevice)
  76 {
  77         me_subdevice_t *pos;
  78         int s_type, s_subtype;
  79         unsigned int index = 0;
  80
  81         PDEBUG_LOCKS("called.\n");
  82
  83         if (start_subdevice >= slist->n) {
  84                 PERROR("Start index out of range.\n");
  85                 return ME_ERRNO_NOMORE_SUBDEVICE_TYPE;
  86         }
  87
  88         list_for_each_entry(pos, &slist->head, list) {
  89                 if (index < start_subdevice) {  // Go forward to start subdevice.
  90                         ++index;
  91                         continue;
  92                 }
  93
  94                 pos->me_subdevice_query_subdevice_type(pos,
  95                                                        &s_type, &s_subtype);
  96
  97                 if (subtype == ME_SUBTYPE_ANY) {
  98                         if (s_type == type)
  99                                 break;
 100                 } else {
 101                         if ((s_type == type) && (s_subtype == subtype))
 102                                 break;
 103                 }
 104
 105                 ++index;
 106         }
 107
 108         if (index >= slist->n) {
 109                 return ME_ERRNO_NOMORE_SUBDEVICE_TYPE;
 110         }
 111
 112         *subdevice = index;
 113
 114         return ME_ERRNO_SUCCESS;
 115 }
 116
 117 void me_slist_add_subdevice_tail(struct me_slist *slist,
 118                                  me_subdevice_t * subdevice)
 119 {
 120         PDEBUG_LOCKS("called.\n");
 121
 122         list_add_tail(&subdevice->list, &slist->head);
 123         ++slist->n;
 124 }
 125
 126 me_subdevice_t *me_slist_del_subdevice_tail(struct me_slist *slist)
 127 {
 128
 129         struct list_head *last;
 130         me_subdevice_t *subdevice;
 131
 132         PDEBUG_LOCKS("called.\n");
 133
 134         if (list_empty(&slist->head))
 135                 return NULL;
 136
 137         last = slist->head.prev;
 138
 139         subdevice = list_entry(last, me_subdevice_t, list);
 140
 141         list_del(last);
 142
 143         --slist->n;
 144
 145         return subdevice;
 146 }
 147
 148 int me_slist_init(me_slist_t * slist)
 149 {
 150         PDEBUG_LOCKS("called.\n");
 151
 152         INIT_LIST_HEAD(&slist->head);
 153         slist->n = 0;
 154         return 0;
 155 }
 156
 157 void me_slist_deinit(me_slist_t * slist)
 158 {
 159
 160         struct list_head *s;
 161         me_subdevice_t *subdevice;
 162
 163         PDEBUG_LOCKS("called.\n");
 164
 165         while (!list_empty(&slist->head)) {
 166                 s = slist->head.next;
 167                 list_del(s);
 168                 subdevice = list_entry(s, me_subdevice_t, list);
 169                 subdevice->me_subdevice_destructor(subdevice);
 170         }
 171
 172         slist->n = 0;
 173 }