drivers/staging/vt6655/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  * File: dpc.c
  16  *
  17  * Purpose: handle dpc rx functions
  18  *
  19  * Author: Lyndon Chen
  20  *
  21  * Date: May 20, 2003
  22  *
  23  * Functions:
  24  *
  25  * Revision History:
  26  *
  27  */
  28
  29 #include "device.h"
  30 #include "baseband.h"
  31 #include "rf.h"
  32 #include "dpc.h"
  33
  34 static bool vnt_rx_data(struct vnt_private *priv, struct sk_buff *skb,
  35                         u16 bytes_received)
  36 {
  37         struct ieee80211_hw *hw = priv->hw;
  38         struct ieee80211_supported_band *sband;
  39         struct ieee80211_rx_status rx_status = { 0 };
  40         struct ieee80211_hdr *hdr;
  41         __le16 fc;
  42         u8 *rsr, *new_rsr, *rssi;
  43         __le64 *tsf_time;
  44         u16 frame_size;
  45         int ii, r;
  46         u8 *rx_sts, *rx_rate, *sq;
  47         u8 *skb_data;
  48         u8 rate_idx = 0;
  49         u8 rate[MAX_RATE] = {2, 4, 11, 22, 12, 18, 24, 36, 48, 72, 96, 108};
  50         long rx_dbm;
  51
  52         /* [31:16]RcvByteCount ( not include 4-byte Status ) */
  53         frame_size = le16_to_cpu(*((__le16 *)(skb->data + 2)));
  54         if (frame_size > 2346 || frame_size < 14) {
  55                 dev_dbg(&priv->pcid->dev, "------- WRONG Length 1\n");
  56                 return false;
  57         }
  58
  59         skb_data = (u8 *)skb->data;
  60
  61         rx_sts = skb_data;
  62         rx_rate = skb_data + 1;
  63
  64         sband = hw->wiphy->bands[hw->conf.chandef.chan->band];
  65
  66         for (r = RATE_1M; r < MAX_RATE; r++) {
  67                 if (*rx_rate == rate[r])
  68                         break;
  69         }
  70
  71         priv->rx_rate = r;
  72
  73         for (ii = 0; ii < sband->n_bitrates; ii++) {
  74                 if (sband->bitrates[ii].hw_value == r) {
  75                         rate_idx = ii;
  76                                 break;
  77                 }
  78         }
  79
  80         if (ii == sband->n_bitrates) {
  81                 dev_dbg(&priv->pcid->dev, "Wrong RxRate %x\n", *rx_rate);
  82                 return false;
  83         }
  84
  85         tsf_time = (__le64 *)(skb_data + bytes_received - 12);
  86         sq = skb_data + bytes_received - 4;
  87         new_rsr = skb_data + bytes_received - 3;
  88         rssi = skb_data + bytes_received - 2;
  89         rsr = skb_data + bytes_received - 1;
  90         if (*rsr & (RSR_IVLDTYP | RSR_IVLDLEN))
  91                 return false;
  92
  93         RFvRSSITodBm(priv, *rssi, &rx_dbm);
  94
  95         priv->byBBPreEDRSSI = (u8)rx_dbm + 1;
  96         priv->uCurrRSSI = *rssi;
  97
  98         skb_pull(skb, 4);
  99         skb_trim(skb, frame_size);
 100
 101         rx_status.mactime = le64_to_cpu(*tsf_time);
 102         rx_status.band = hw->conf.chandef.chan->band;
 103         rx_status.signal = rx_dbm;
 104         rx_status.flag = 0;
 105         rx_status.freq = hw->conf.chandef.chan->center_freq;
 106
 107         if (!(*rsr & RSR_CRCOK))
 108                 rx_status.flag |= RX_FLAG_FAILED_FCS_CRC;
 109
 110         hdr = (struct ieee80211_hdr *)(skb->data);
 111         fc = hdr->frame_control;
 112
 113         rx_status.rate_idx = rate_idx;
 114
 115         if (ieee80211_has_protected(fc)) {
 116                 if (priv->byLocalID > REV_ID_VT3253_A1)
 117                         rx_status.flag |= RX_FLAG_DECRYPTED;
 118
 119                 /* Drop packet */
 120                 if (!(*new_rsr & NEWRSR_DECRYPTOK))
 121                         return false;
 122         }
 123
 124         memcpy(IEEE80211_SKB_RXCB(skb), &rx_status, sizeof(rx_status));
 125
 126         ieee80211_rx_irqsafe(priv->hw, skb);
 127
 128         return true;
 129 }
 130
 131 bool vnt_receive_frame(struct vnt_private *priv, struct vnt_rx_desc *curr_rd)
 132 {
 133         struct vnt_rd_info *rd_info = curr_rd->rd_info;
 134         struct sk_buff *skb;
 135         u16 frame_size;
 136
 137         skb = rd_info->skb;
 138
 139         dma_unmap_single(&priv->pcid->dev, rd_info->skb_dma,
 140                          priv->rx_buf_sz, DMA_FROM_DEVICE);
 141
 142         frame_size = le16_to_cpu(curr_rd->rd1.req_count)
 143                         - le16_to_cpu(curr_rd->rd0.res_count);
 144
 145         if ((frame_size > 2364) || (frame_size < 33)) {
 146                 /* Frame Size error drop this packet.*/
 147                 dev_dbg(&priv->pcid->dev, "Wrong frame size %d\n", frame_size);
 148                 dev_kfree_skb_irq(skb);
 149                 return true;
 150         }
 151
 152         if (vnt_rx_data(priv, skb, frame_size))
 153                 return true;
 154
 155         dev_kfree_skb_irq(skb);
 156
 157         return true;
 158 }