drivers/staging/vt6656/dpc.c

   1 /*
   2  * Copyright (c) 1996, 2003 VIA Networking Technologies, Inc.
   3  * All rights reserved.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   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  *
  16  * File: dpc.c
  17  *
  18  * Purpose: handle dpc rx functions
  19  *
  20  * Author: Lyndon Chen
  21  *
  22  * Date: May 20, 2003
  23  *
  24  * Functions:
  25  *
  26  * Revision History:
  27  *
  28  */
  29
  30 #include "dpc.h"
  31 #include "device.h"
  32 #include "mac.h"
  33 #include "baseband.h"
  34 #include "rf.h"
  35
  36 int vnt_rx_data(struct vnt_private *priv, struct vnt_rcb *ptr_rcb,
  37         unsigned long bytes_received)
  38 {
  39         struct ieee80211_hw *hw = priv->hw;
  40         struct ieee80211_supported_band *sband;
  41         struct sk_buff *skb;
  42         struct ieee80211_rx_status rx_status = { 0 };
  43         struct ieee80211_hdr *hdr;
  44         __le16 fc;
  45         u8 *rsr, *new_rsr, *rssi, *frame;
  46         __le64 *tsf_time;
  47         u32 frame_size;
  48         int ii, r;
  49         u8 *rx_sts, *rx_rate, *sq, *sq_3;
  50         u32 wbk_status;
  51         u8 *skb_data;
  52         u16 *pay_load_len;
  53         u16 pay_load_with_padding;
  54         u8 rate_idx = 0;
  55         u8 rate[MAX_RATE] = {2, 4, 11, 22, 12, 18, 24, 36, 48, 72, 96, 108};
  56         long rx_dbm;
  57
  58         skb = ptr_rcb->skb;
  59
  60         /* [31:16]RcvByteCount ( not include 4-byte Status ) */
  61         wbk_status = *((u32 *)(skb->data));
  62         frame_size = wbk_status >> 16;
  63         frame_size += 4;
  64
  65         if (bytes_received != frame_size) {
  66                 dev_dbg(&priv->usb->dev, "------- WRONG Length 1\n");
  67                 return false;
  68         }
  69
  70         if ((bytes_received > 2372) || (bytes_received <= 40)) {
  71                 /* Frame Size error drop this packet.*/
  72                 dev_dbg(&priv->usb->dev, "------ WRONG Length 2\n");
  73                 return false;
  74         }
  75
  76         skb_data = (u8 *)skb->data;
  77
  78         rx_sts = skb_data+4;
  79         rx_rate = skb_data+5;
  80
  81         /* real Frame Size = USBframe_size -4WbkStatus - 4RxStatus */
  82         /* -8TSF - 4RSR - 4SQ3 - ?Padding */
  83
  84         /* if SQ3 the range is 24~27, if no SQ3 the range is 20~23 */
  85
  86         pay_load_len = (u16 *) (skb_data + 6);
  87
  88         /*Fix hardware bug => PLCP_Length error */
  89         if (((bytes_received - (*pay_load_len)) > 27) ||
  90                 ((bytes_received - (*pay_load_len)) < 24) ||
  91                         (bytes_received < (*pay_load_len))) {
  92                 dev_dbg(&priv->usb->dev, "Wrong PLCP Length %x\n",
  93                                                         *pay_load_len);
  94                 return false;
  95         }
  96
  97         sband = hw->wiphy->bands[hw->conf.chandef.chan->band];
  98
  99         for (r = RATE_1M; r < MAX_RATE; r++) {
 100                 if (*rx_rate == rate[r])
 101                         break;
 102         }
 103
 104         priv->rx_rate = r;
 105
 106         for (ii = 0; ii < sband->n_bitrates; ii++) {
 107                 if (sband->bitrates[ii].hw_value == r) {
 108                         rate_idx = ii;
 109                                 break;
 110                 }
 111         }
 112
 113         if (ii == sband->n_bitrates) {
 114                 dev_dbg(&priv->usb->dev, "Wrong RxRate %x\n", *rx_rate);
 115                 return false;
 116         }
 117
 118         pay_load_with_padding = ((*pay_load_len / 4) +
 119                 ((*pay_load_len % 4) ? 1 : 0)) * 4;
 120
 121         tsf_time = (__le64 *)(skb_data + 8 + pay_load_with_padding);
 122
 123         priv->tsf_time = le64_to_cpu(*tsf_time);
 124
 125         if (priv->bb_type == BB_TYPE_11G) {
 126                 sq_3 = skb_data + 8 + pay_load_with_padding + 12;
 127                 sq = sq_3;
 128         } else {
 129                 sq = skb_data + 8 + pay_load_with_padding + 8;
 130                 sq_3 = sq;
 131         }
 132
 133         new_rsr = skb_data + 8 + pay_load_with_padding + 9;
 134         rssi = skb_data + 8 + pay_load_with_padding + 10;
 135
 136         rsr = skb_data + 8 + pay_load_with_padding + 11;
 137         if (*rsr & (RSR_IVLDTYP | RSR_IVLDLEN))
 138                 return false;
 139
 140         frame_size = *pay_load_len;
 141
 142         vnt_rf_rssi_to_dbm(priv, *rssi, &rx_dbm);
 143
 144         priv->bb_pre_ed_rssi = (u8)rx_dbm + 1;
 145         priv->current_rssi = priv->bb_pre_ed_rssi;
 146
 147         frame = skb_data + 8;
 148
 149         skb_pull(skb, 8);
 150         skb_trim(skb, frame_size);
 151
 152         rx_status.mactime = priv->tsf_time;
 153         rx_status.band = hw->conf.chandef.chan->band;
 154         rx_status.signal = rx_dbm;
 155         rx_status.flag = 0;
 156         rx_status.freq = hw->conf.chandef.chan->center_freq;
 157
 158         if (!(*rsr & RSR_CRCOK))
 159                 rx_status.flag |= RX_FLAG_FAILED_FCS_CRC;
 160
 161         hdr = (struct ieee80211_hdr *)(skb->data);
 162         fc = hdr->frame_control;
 163
 164         rx_status.rate_idx = rate_idx;
 165
 166         if (ieee80211_has_protected(fc)) {
 167                 if (priv->local_id > REV_ID_VT3253_A1) {
 168                         rx_status.flag |= RX_FLAG_DECRYPTED;
 169
 170                         /* Drop packet */
 171                         if (!(*new_rsr & NEWRSR_DECRYPTOK)) {
 172                                 dev_kfree_skb(skb);
 173                                 return true;
 174                         }
 175                 }
 176         }
 177
 178         memcpy(IEEE80211_SKB_RXCB(skb), &rx_status, sizeof(rx_status));
 179
 180         ieee80211_rx_irqsafe(priv->hw, skb);
 181
 182         return true;
 183 }