mac80211: add rx status flag for short preamble

and use it for the radiotap header
Signed-off-by: Bruno Randolf <br1@einfach.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

include/net/mac80211.h

@@ -363,6 +363,7 @@ static inline struct ieee80211_tx_info *IEEE80211_SKB_CB(struct sk_buff *skb)
  * @RX_FLAG_TSFT: The timestamp passed in the RX status (@mactime field)
  *	is valid. This is useful in monitor mode and necessary for beacon frames
  *	to enable IBSS merging.
+ * @RX_FLAG_SHORTPRE: Short preamble was used for this frame
  */
 enum mac80211_rx_flags {
 	RX_FLAG_MMIC_ERROR	= 1<<0,
@@ -373,6 +374,7 @@ enum mac80211_rx_flags {
 	RX_FLAG_FAILED_FCS_CRC	= 1<<5,
 	RX_FLAG_FAILED_PLCP_CRC = 1<<6,
 	RX_FLAG_TSFT		= 1<<7,
+	RX_FLAG_SHORTPRE	= 1<<8
 };
 
 /**

net/mac80211/rx.c

@@ -143,6 +143,8 @@ ieee80211_add_rx_radiotap_header(struct ieee80211_local *local,
 	/* IEEE80211_RADIOTAP_FLAGS */
 	if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
 		*pos |= IEEE80211_RADIOTAP_F_FCS;
+	if (status->flag & RX_FLAG_SHORTPRE)
+		*pos |= IEEE80211_RADIOTAP_F_SHORTPRE;
 	pos++;
 
 	/* IEEE80211_RADIOTAP_RATE */