release/src-rt-6.x.4708/linux/linux-2.6.36/drivers/staging/otus/80211core/cwm.c

   1 /*
   2  * Copyright (c) 2007-2008 Atheros Communications Inc.
   3  *
   4  * Permission to use, copy, modify, and/or distribute this software for any
   5  * purpose with or without fee is hereby granted, provided that the above
   6  * copyright notice and this permission notice appear in all copies.
   7  *
   8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
   9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  15  */
  16 /*                                                                      */
  17 /*  Module Name : cwm.c                                                 */
  18 /*                                                                      */
  19 /*  Abstract                                                            */
  20 /*      This module contains channel width related functions.           */
  21 /*                                                                      */
  22 /*  NOTES                                                               */
  23 /*      None                                                            */
  24 /*                                                                      */
  25 /************************************************************************/
  26
  27 #include "cprecomp.h"
  28
  29
  30
  31 void zfCwmInit(zdev_t* dev) {
  32     //u16_t i;
  33     zmw_get_wlan_dev(dev);
  34
  35     switch (wd->wlanMode) {
  36     case ZM_MODE_AP:
  37         wd->cwm.cw_mode = CWM_MODE2040;
  38         wd->cwm.cw_width = CWM_WIDTH40;
  39         wd->cwm.cw_enable = 1;
  40         break;
  41     case ZM_MODE_INFRASTRUCTURE:
  42     case ZM_MODE_PSEUDO:
  43     case ZM_MODE_IBSS:
  44     default:
  45         wd->cwm.cw_mode = CWM_MODE2040;
  46         wd->cwm.cw_width = CWM_WIDTH20;
  47         wd->cwm.cw_enable = 1;
  48         break;
  49     }
  50 }
  51
  52
  53 void zfCoreCwmBusy(zdev_t* dev, u16_t busy)
  54 {
  55
  56     zmw_get_wlan_dev(dev);
  57
  58     zm_msg1_mm(ZM_LV_0, "CwmBusy=", busy);
  59
  60     if(wd->cwm.cw_mode == CWM_MODE20) {
  61         wd->cwm.cw_width = CWM_WIDTH20;
  62         return;
  63     }
  64
  65     if(wd->cwm.cw_mode == CWM_MODE40) {
  66         wd->cwm.cw_width = CWM_WIDTH40;
  67         return;
  68     }
  69
  70     if (busy) {
  71         wd->cwm.cw_width = CWM_WIDTH20;
  72         return;
  73     }
  74
  75
  76     if((wd->wlanMode == ZM_MODE_INFRASTRUCTURE || wd->wlanMode == ZM_MODE_PSEUDO ||
  77         wd->wlanMode == ZM_MODE_IBSS)) {
  78         if ((wd->sta.ie.HtCap.HtCapInfo & HTCAP_SupChannelWidthSet) &&
  79             (wd->sta.ie.HtInfo.ChannelInfo & ExtHtCap_RecomTxWidthSet) &&
  80             (wd->sta.ie.HtInfo.ChannelInfo & ExtHtCap_ExtChannelOffsetAbove)) {
  81
  82             wd->cwm.cw_width = CWM_WIDTH40;
  83         }
  84         else {
  85             wd->cwm.cw_width = CWM_WIDTH20;
  86         }
  87
  88         return;
  89     }
  90
  91     if(wd->wlanMode == ZM_MODE_AP) {
  92         wd->cwm.cw_width = CWM_WIDTH40;
  93     }
  94
  95 }
  96
  97
  98
  99
 100 u16_t zfCwmIsExtChanBusy(u32_t ctlBusy, u32_t extBusy)
 101 {
 102     u32_t busy; /* percentage */
 103     u32_t cycleTime, ctlClear;
 104
 105     cycleTime = 1280000; //1.28 seconds
 106
 107     if (cycleTime > ctlBusy) {
 108         ctlClear = cycleTime - ctlBusy;
 109     }
 110     else
 111     {
 112         ctlClear = 0;
 113     }
 114
 115     /* Compute ratio of extension channel busy to control channel clear
 116      * as an approximation to extension channel cleanliness.
 117      *
 118      * According to the hardware folks, ext rxclear is undefined
 119      * if the ctrl rxclear is de-asserted (i.e. busy)
 120      */
 121     if (ctlClear) {
 122         busy = (extBusy * 100) / ctlClear;
 123     } else {
 124         busy = 0;
 125     }
 126     if (busy > ATH_CWM_EXTCH_BUSY_THRESHOLD) {
 127         return TRUE;
 128     }
 129
 130     return FALSE;
 131 }