ath9k: move ath9k_rx_skb_postprocess to common.c

and rename it to ath9k_cmn_rx_skb_postprocess. We will use it
on ath9k_htc.

Signed-off-by: Oleksij Rempel <linux@rempel-privat.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/ath/ath9k/common.c b/drivers/net/wireless/ath/ath9k/common.c
index 5c0d949..c6dd7f1 100644
--- a/drivers/net/wireless/ath/ath9k/common.c
+++ b/drivers/net/wireless/ath/ath9k/common.c
@@ -115,6 +115,58 @@
 }
 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,