unsigned int ielength = 0;
        unsigned int i, j;
 
-       i = 12; /* after the fixed IE */
+       i = _FIXED_IE_LENGTH_; /* after the fixed IE */
        while (i < in_len) {
                ielength = initial_out_len;
 
                  "ndissecuritytype=%d\n", ndisauthmode, ndissecuritytype));
 
        /* copy fixed ie only */
-       memcpy(out_ie, in_ie, 12);
-       ielength = 12;
+       memcpy(out_ie, in_ie, _FIXED_IE_LENGTH_);
+       ielength = _FIXED_IE_LENGTH_;
        if (ndisauthmode == Ndis802_11AuthModeWPA ||
            ndisauthmode == Ndis802_11AuthModeWPAPSK)
                authmode = WLAN_EID_VENDOR_SPECIFIC;
 
        phtpriv->ht_option = false;
 
-       p = cfg80211_find_ie(WLAN_EID_HT_CAPABILITY, in_ie + 12, in_len -12);
+       p = cfg80211_find_ie(WLAN_EID_HT_CAPABILITY, in_ie + _FIXED_IE_LENGTH_,
+                            in_len - _FIXED_IE_LENGTH_);
 
        if (p && p[1] > 0) {
                u32 rx_packet_offset, max_recvbuf_sz;
 
                phtpriv->ht_option = true;
 
-               p = cfg80211_find_ie(WLAN_EID_HT_OPERATION, in_ie + 12,
-                                    in_len -12);
+               p = cfg80211_find_ie(WLAN_EID_HT_OPERATION,
+                                    in_ie + _FIXED_IE_LENGTH_,
+                                    in_len - _FIXED_IE_LENGTH_);
                if (p && (p[1] == sizeof(struct ieee80211_ht_operation))) {
                        out_len = *pout_len;
                        pframe = rtw_set_ie23a(out_ie + out_len,