drivers/staging/vt6656/dpc.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Copyright (c) 1996, 2003 VIA Networking Technologies, Inc.
   4  * All rights reserved.
   5  *
   6  * File: dpc.c
   7  *
   8  * Purpose: handle dpc rx functions
   9  *
  10  * Author: Lyndon Chen
  11  *
  12  * Date: May 20, 2003
  13  *
  14  * Functions:
  15  *
  16  * Revision History:
  17  *
  18  */
  19
  20 #include "dpc.h"
  21 #include "device.h"
  22 #include "mac.h"
  23 #include "baseband.h"
  24 #include "rf.h"
  25
  26 int vnt_rx_data(struct vnt_private *priv, struct vnt_rcb *ptr_rcb,
  27                 unsigned long bytes_received)
  28 {
  29         struct ieee80211_hw *hw = priv->hw;
  30         struct ieee80211_supported_band *sband;
  31         struct sk_buff *skb;
  32         struct ieee80211_rx_status *rx_status;
  33         struct vnt_rx_header *head;
  34         struct vnt_rx_tail *tail;
  35         u32 frame_size;
  36         int ii;
  37         u16 rx_bitrate, pay_load_with_padding;
  38         u8 rate_idx = 0;
  39         long rx_dbm;
  40
  41         skb = ptr_rcb->skb;
  42         rx_status = IEEE80211_SKB_RXCB(skb);
  43
  44         /* [31:16]RcvByteCount ( not include 4-byte Status ) */
  45         head = (struct vnt_rx_header *)skb->data;
  46         frame_size = head->wbk_status >> 16;
  47         frame_size += 4;
  48
  49         if (bytes_received != frame_size) {
  50                 dev_dbg(&priv->usb->dev, "------- WRONG Length 1\n");
  51                 return false;
  52         }
  53
  54         if ((bytes_received > 2372) || (bytes_received <= 40)) {
  55                 /* Frame Size error drop this packet.*/
  56                 dev_dbg(&priv->usb->dev, "------ WRONG Length 2\n");
  57                 return false;
  58         }
  59
  60         /* real Frame Size = USBframe_size -4WbkStatus - 4RxStatus */
  61         /* -8TSF - 4RSR - 4SQ3 - ?Padding */
  62
  63         /* if SQ3 the range is 24~27, if no SQ3 the range is 20~23 */
  64
  65         /*Fix hardware bug => PLCP_Length error */
  66         if (((bytes_received - head->pay_load_len) > 27) ||
  67             ((bytes_received - head->pay_load_len) < 24) ||
  68             (bytes_received < head->pay_load_len)) {
  69                 dev_dbg(&priv->usb->dev, "Wrong PLCP Length %x\n",
  70                         head->pay_load_len);
  71                 return false;
  72         }
  73
  74         sband = hw->wiphy->bands[hw->conf.chandef.chan->band];
  75         rx_bitrate = head->rx_rate * 5; /* rx_rate * 5 */
  76
  77         for (ii = 0; ii < sband->n_bitrates; ii++) {
  78                 if (sband->bitrates[ii].bitrate == rx_bitrate) {
  79                         rate_idx = ii;
  80                                 break;
  81                 }
  82         }
  83
  84         if (ii == sband->n_bitrates) {
  85                 dev_dbg(&priv->usb->dev, "Wrong Rx Bit Rate %d\n", rx_bitrate);
  86                 return false;
  87         }
  88
  89         pay_load_with_padding = ((head->pay_load_len / 4) +
  90                 ((head->pay_load_len % 4) ? 1 : 0)) * 4;
  91
  92         tail = (struct vnt_rx_tail *)(skb->data +
  93                                       sizeof(*head) + pay_load_with_padding);
  94         priv->tsf_time = le64_to_cpu(tail->tsf_time);
  95
  96         if (tail->rsr & (RSR_IVLDTYP | RSR_IVLDLEN))
  97                 return false;
  98
  99         vnt_rf_rssi_to_dbm(priv, tail->rssi, &rx_dbm);
 100
 101         priv->bb_pre_ed_rssi = (u8)-rx_dbm + 1;
 102         priv->current_rssi = priv->bb_pre_ed_rssi;
 103
 104         skb_pull(skb, sizeof(*head));
 105         skb_trim(skb, head->pay_load_len);
 106
 107         rx_status->mactime = priv->tsf_time;
 108         rx_status->band = hw->conf.chandef.chan->band;
 109         rx_status->signal = rx_dbm;
 110         rx_status->flag = 0;
 111         rx_status->freq = hw->conf.chandef.chan->center_freq;
 112
 113         if (!(tail->rsr & RSR_CRCOK))
 114                 rx_status->flag |= RX_FLAG_FAILED_FCS_CRC;
 115
 116         rx_status->rate_idx = rate_idx;
 117
 118         if (tail->new_rsr & NEWRSR_DECRYPTOK)
 119                 rx_status->flag |= RX_FLAG_DECRYPTED;
 120
 121         ieee80211_rx_irqsafe(priv->hw, skb);
 122
 123         return true;
 124 }