net/wireless/util.c

   1 /*
   2  * Wireless utility functions
   3  *
   4  * Copyright 2007       Johannes Berg <johannes@sipsolutions.net>
   5  */
   6 #include <net/wireless.h>
   7 #include <asm/bitops.h>
   8 #include "core.h"
   9
  10 int ieee80211_channel_to_frequency(int chan)
  11 {
  12         if (chan < 14)
  13                 return 2407 + chan * 5;
  14
  15         if (chan == 14)
  16                 return 2484;
  17
  18         /* FIXME: 802.11j 17.3.8.3.2 */
  19         return (chan + 1000) * 5;
  20 }
  21 EXPORT_SYMBOL(ieee80211_channel_to_frequency);
  22
  23 int ieee80211_frequency_to_channel(int freq)
  24 {
  25         if (freq == 2484)
  26                 return 14;
  27
  28         if (freq < 2484)
  29                 return (freq - 2407) / 5;
  30
  31         /* FIXME: 802.11j 17.3.8.3.2 */
  32         return freq/5 - 1000;
  33 }
  34 EXPORT_SYMBOL(ieee80211_frequency_to_channel);
  35
  36 struct ieee80211_channel *__ieee80211_get_channel(struct wiphy *wiphy,
  37                                                   int freq)
  38 {
  39         enum ieee80211_band band;
  40         struct ieee80211_supported_band *sband;
  41         int i;
  42
  43         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
  44                 sband = wiphy->bands[band];
  45
  46                 if (!sband)
  47                         continue;
  48
  49                 for (i = 0; i < sband->n_channels; i++) {
  50                         if (sband->channels[i].center_freq == freq)
  51                                 return &sband->channels[i];
  52                 }
  53         }
  54
  55         return NULL;
  56 }
  57 EXPORT_SYMBOL(__ieee80211_get_channel);
  58
  59 static void set_mandatory_flags_band(struct ieee80211_supported_band *sband,
  60                                      enum ieee80211_band band)
  61 {
  62         int i, want;
  63
  64         switch (band) {
  65         case IEEE80211_BAND_5GHZ:
  66                 want = 3;
  67                 for (i = 0; i < sband->n_bitrates; i++) {
  68                         if (sband->bitrates[i].bitrate == 60 ||
  69                             sband->bitrates[i].bitrate == 120 ||
  70                             sband->bitrates[i].bitrate == 240) {
  71                                 sband->bitrates[i].flags |=
  72                                         IEEE80211_RATE_MANDATORY_A;
  73                                 want--;
  74                         }
  75                 }
  76                 WARN_ON(want);
  77                 break;
  78         case IEEE80211_BAND_2GHZ:
  79                 want = 7;
  80                 for (i = 0; i < sband->n_bitrates; i++) {
  81                         if (sband->bitrates[i].bitrate == 10) {
  82                                 sband->bitrates[i].flags |=
  83                                         IEEE80211_RATE_MANDATORY_B |
  84                                         IEEE80211_RATE_MANDATORY_G;
  85                                 want--;
  86                         }
  87
  88                         if (sband->bitrates[i].bitrate == 20 ||
  89                             sband->bitrates[i].bitrate == 55 ||
  90                             sband->bitrates[i].bitrate == 110 ||
  91                             sband->bitrates[i].bitrate == 60 ||
  92                             sband->bitrates[i].bitrate == 120 ||
  93                             sband->bitrates[i].bitrate == 240) {
  94                                 sband->bitrates[i].flags |=
  95                                         IEEE80211_RATE_MANDATORY_G;
  96                                 want--;
  97                         }
  98
  99                         if (sband->bitrates[i].bitrate != 10 &&
 100                             sband->bitrates[i].bitrate != 20 &&
 101                             sband->bitrates[i].bitrate != 55 &&
 102                             sband->bitrates[i].bitrate != 110)
 103                                 sband->bitrates[i].flags |=
 104                                         IEEE80211_RATE_ERP_G;
 105                 }
 106                 WARN_ON(want != 0 && want != 3 && want != 6);
 107                 break;
 108         case IEEE80211_NUM_BANDS:
 109                 WARN_ON(1);
 110                 break;
 111         }
 112 }
 113
 114 void ieee80211_set_bitrate_flags(struct wiphy *wiphy)
 115 {
 116         enum ieee80211_band band;
 117
 118         for (band = 0; band < IEEE80211_NUM_BANDS; band++)
 119                 if (wiphy->bands[band])
 120                         set_mandatory_flags_band(wiphy->bands[band], band);
 121 }