1 files changed, 244 insertions, 0 deletions

diff --git a/drivers/net/wireless/ath/ath9k/common.c b/drivers/net/wireless/ath/ath9k/common.c
index 768c733cad31..c6dd7f1fed65 100644
--- a/drivers/net/wireless/ath/ath9k/common.c
+++ b/drivers/net/wireless/ath/ath9k/common.c
@@ -27,6 +27,250 @@ MODULE_AUTHOR("Atheros Communications");
 MODULE_DESCRIPTION("Shared library for Atheros wireless 802.11n LAN cards.");
 MODULE_LICENSE("Dual BSD/GPL");
 
+/* Assumes you've already done the endian to CPU conversion */
+bool ath9k_cmn_rx_accept(struct ath_common *common,
+			 struct ieee80211_hdr *hdr,
+			 struct ieee80211_rx_status *rxs,
+			 struct ath_rx_status *rx_stats,
+			 bool *decrypt_error,
+			 unsigned int rxfilter)
+{
+	struct ath_hw *ah = common->ah;
+	bool is_mc, is_valid_tkip, strip_mic, mic_error;
+	__le16 fc;
+
+	fc = hdr->frame_control;
+
+	is_mc = !!is_multicast_ether_addr(hdr->addr1);
+	is_valid_tkip = rx_stats->rs_keyix != ATH9K_RXKEYIX_INVALID &&
+		test_bit(rx_stats->rs_keyix, common->tkip_keymap);
+	strip_mic = is_valid_tkip && ieee80211_is_data(fc) &&
+		ieee80211_has_protected(fc) &&
+		!(rx_stats->rs_status &
+		(ATH9K_RXERR_DECRYPT | ATH9K_RXERR_CRC | ATH9K_RXERR_MIC |
+		 ATH9K_RXERR_KEYMISS));
+
+	/*
+	 * Key miss events are only relevant for pairwise keys where the
+	 * descriptor does contain a valid key index. This has been observed
+	 * mostly with CCMP encryption.
+	 */
+	if (rx_stats->rs_keyix == ATH9K_RXKEYIX_INVALID ||
+	    !test_bit(rx_stats->rs_keyix, common->ccmp_keymap))
+		rx_stats->rs_status &= ~ATH9K_RXERR_KEYMISS;
+
+	mic_error = is_valid_tkip && !ieee80211_is_ctl(fc) &&
+		!ieee80211_has_morefrags(fc) &&
+		!(le16_to_cpu(hdr->seq_ctrl) & IEEE80211_SCTL_FRAG) &&
+		(rx_stats->rs_status & ATH9K_RXERR_MIC);
+
+	/*
+	 * The rx_stats->rs_status will not be set until the end of the
+	 * chained descriptors so it can be ignored if rs_more is set. The
+	 * rs_more will be false at the last element of the chained
+	 * descriptors.
+	 */
+	if (rx_stats->rs_status != 0) {
+		u8 status_mask;
+
+		if (rx_stats->rs_status & ATH9K_RXERR_CRC) {
+			rxs->flag |= RX_FLAG_FAILED_FCS_CRC;
+			mic_error = false;
+		}
+
+		if ((rx_stats->rs_status & ATH9K_RXERR_DECRYPT) ||
+		    (!is_mc && (rx_stats->rs_status & ATH9K_RXERR_KEYMISS))) {
+			*decrypt_error = true;
+			mic_error = false;
+		}
+
+
+		/*
+		 * Reject error frames with the exception of
+		 * decryption and MIC failures. For monitor mode,
+		 * we also ignore the CRC error.
+		 */
+		status_mask = ATH9K_RXERR_DECRYPT | ATH9K_RXERR_MIC |
+			      ATH9K_RXERR_KEYMISS;
+
+		if (ah->is_monitoring && (rxfilter & FIF_FCSFAIL))
+			status_mask |= ATH9K_RXERR_CRC;
+
+		if (rx_stats->rs_status & ~status_mask)
+			return false;
+	}
+
+	/*
+	 * For unicast frames the MIC error bit can have false positives,
+	 * so all MIC error reports need to be validated in software.
+	 * False negatives are not common, so skip software verification
+	 * if the hardware considers the MIC valid.
+	 */
+	if (strip_mic)
+		rxs->flag |= RX_FLAG_MMIC_STRIPPED;
+	else if (is_mc && mic_error)
+		rxs->flag |= RX_FLAG_MMIC_ERROR;
+
+	return true;
+}
+EXPORT_SYMBOL(ath9k_cmn_rx_accept);
+
+void ath9k_cmn_rx_skb_postprocess(struct ath_common *common,
+				  struct sk_buff *skb,
+				  struct ath_rx_status *rx_stats,
+				  struct ieee80211_rx_status *rxs,
+				  bool decrypt_error)
+{
+	struct ath_hw *ah = common->ah;
+	struct ieee80211_hdr *hdr;
+	int hdrlen, padpos, padsize;
+	u8 keyix;
+	__le16 fc;
+
+	/* see if any padding is done by the hw and remove it */
+	hdr = (struct ieee80211_hdr *) skb->data;
+	hdrlen = ieee80211_get_hdrlen_from_skb(skb);
+	fc = hdr->frame_control;
+	padpos = ieee80211_hdrlen(fc);
+
+	/* The MAC header is padded to have 32-bit boundary if the
+	 * packet payload is non-zero. The general calculation for
+	 * padsize would take into account odd header lengths:
+	 * padsize = (4 - padpos % 4) % 4; However, since only
+	 * even-length headers are used, padding can only be 0 or 2
+	 * bytes and we can optimize this a bit. In addition, we must
+	 * not try to remove padding from short control frames that do
+	 * not have payload. */
+	padsize = padpos & 3;
+	if (padsize && skb->len>=padpos+padsize+FCS_LEN) {
+		memmove(skb->data + padsize, skb->data, padpos);
+		skb_pull(skb, padsize);
+	}
+
+	keyix = rx_stats->rs_keyix;
+
+	if (!(keyix == ATH9K_RXKEYIX_INVALID) && !decrypt_error &&
+	    ieee80211_has_protected(fc)) {
+		rxs->flag |= RX_FLAG_DECRYPTED;
+	} else if (ieee80211_has_protected(fc)
+		   && !decrypt_error && skb->len >= hdrlen + 4) {
+		keyix = skb->data[hdrlen + 3] >> 6;
+
+		if (test_bit(keyix, common->keymap))
+			rxs->flag |= RX_FLAG_DECRYPTED;
+	}
+	if (ah->sw_mgmt_crypto &&
+	    (rxs->flag & RX_FLAG_DECRYPTED) &&
+	    ieee80211_is_mgmt(fc))
+		/* Use software decrypt for management frames. */
+		rxs->flag &= ~RX_FLAG_DECRYPTED;
+}
+EXPORT_SYMBOL(ath9k_cmn_rx_skb_postprocess);
+
+int ath9k_cmn_process_rate(struct ath_common *common,
+			   struct ieee80211_hw *hw,
+			   struct ath_rx_status *rx_stats,
+			   struct ieee80211_rx_status *rxs)
+{
+	struct ieee80211_supported_band *sband;
+	enum ieee80211_band band;
+	unsigned int i = 0;
+	struct ath_hw *ah = common->ah;
+
+	band = ah->curchan->chan->band;
+	sband = hw->wiphy->bands[band];
+
+	if (IS_CHAN_QUARTER_RATE(ah->curchan))
+		rxs->flag |= RX_FLAG_5MHZ;
+	else if (IS_CHAN_HALF_RATE(ah->curchan))
+		rxs->flag |= RX_FLAG_10MHZ;
+
+	if (rx_stats->rs_rate & 0x80) {
+		/* HT rate */
+		rxs->flag |= RX_FLAG_HT;
+		rxs->flag |= rx_stats->flag;
+		rxs->rate_idx = rx_stats->rs_rate & 0x7f;
+		return 0;
+	}
+
+	for (i = 0; i < sband->n_bitrates; i++) {
+		if (sband->bitrates[i].hw_value == rx_stats->rs_rate) {
+			rxs->rate_idx = i;
+			return 0;
+		}
+		if (sband->bitrates[i].hw_value_short == rx_stats->rs_rate) {
+			rxs->flag |= RX_FLAG_SHORTPRE;
+			rxs->rate_idx = i;
+			return 0;
+		}
+	}
+
+	return -EINVAL;
+}
+EXPORT_SYMBOL(ath9k_cmn_process_rate);
+
+void ath9k_cmn_process_rssi(struct ath_common *common,
+			    struct ieee80211_hw *hw,
+			    struct ath_rx_status *rx_stats,
+			    struct ieee80211_rx_status *rxs)
+{
+	struct ath_hw *ah = common->ah;
+	int last_rssi;
+	int rssi = rx_stats->rs_rssi;
+	int i, j;
+
+	/*
+	 * RSSI is not available for subframes in an A-MPDU.
+	 */
+	if (rx_stats->rs_moreaggr) {
+		rxs->flag |= RX_FLAG_NO_SIGNAL_VAL;
+		return;
+	}
+
+	/*
+	 * Check if the RSSI for the last subframe in an A-MPDU
+	 * or an unaggregated frame is valid.
+	 */
+	if (rx_stats->rs_rssi == ATH9K_RSSI_BAD) {
+		rxs->flag |= RX_FLAG_NO_SIGNAL_VAL;
+		return;
+	}
+
+	for (i = 0, j = 0; i < ARRAY_SIZE(rx_stats->rs_rssi_ctl); i++) {
+		s8 rssi;
+
+		if (!(ah->rxchainmask & BIT(i)))
+			continue;
+
+		rssi = rx_stats->rs_rssi_ctl[i];
+		if (rssi != ATH9K_RSSI_BAD) {
+		    rxs->chains |= BIT(j);
+		    rxs->chain_signal[j] = ah->noise + rssi;
+		}
+		j++;
+	}
+
+	/*
+	 * Update Beacon RSSI, this is used by ANI.
+	 */
+	if (rx_stats->is_mybeacon &&
+	    ((ah->opmode == NL80211_IFTYPE_STATION) ||
+	     (ah->opmode == NL80211_IFTYPE_ADHOC))) {
+		ATH_RSSI_LPF(common->last_rssi, rx_stats->rs_rssi);
+		last_rssi = common->last_rssi;
+
+		if (likely(last_rssi != ATH_RSSI_DUMMY_MARKER))
+			rssi = ATH_EP_RND(last_rssi, ATH_RSSI_EP_MULTIPLIER);
+		if (rssi < 0)
+			rssi = 0;
+
+		ah->stats.avgbrssi = rssi;
+	}
+
+	rxs->signal = ah->noise + rx_stats->rs_rssi;
+}
+EXPORT_SYMBOL(ath9k_cmn_process_rssi);
+
 int ath9k_cmn_get_hw_crypto_keytype(struct sk_buff *skb)
 {
 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);