mac80211: Add documentation bits for mac80211_rate_control_flags

Signed-off-by: Sujith <Sujith.Manoharan@atheros.com>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

include/net/mac80211.h

@@ -262,6 +262,26 @@ enum mac80211_tx_control_flags {
 	IEEE80211_TX_CTL_RATE_CTRL_PROBE	= BIT(12),
 };
 
+/**
+ * enum mac80211_rate_control_flags - per-rate flags set by the
+ *	Rate Control algorithm.
+ *
+ * These flags are set by the Rate control algorithm for each rate during tx,
+ * in the @flags member of struct ieee80211_tx_rate.
+ *
+ * @IEEE80211_TX_RC_USE_RTS_CTS: Use RTS/CTS exchange for this rate.
+ * @IEEE80211_TX_RC_USE_CTS_PROTECT: CTS-to-self protection is required.
+ *	This is set if the current BSS requires ERP protection.
+ * @IEEE80211_TX_RC_USE_SHORT_PREAMBLE: Use short preamble.
+ * @IEEE80211_TX_RC_MCS: HT rate.
+ * @IEEE80211_TX_RC_GREEN_FIELD: Indicates whether this rate should be used in
+ *	Greenfield mode.
+ * @IEEE80211_TX_RC_40_MHZ_WIDTH: Indicates if the Channel Width should be 40 MHz.
+ * @IEEE80211_TX_RC_DUP_DATA: The frame should be transmitted on both of the
+ *	adjacent 20 MHz channels, if the current channel type is
+ *	NL80211_CHAN_HT40MINUS or NL80211_CHAN_HT40PLUS.
+ * @IEEE80211_TX_RC_SHORT_GI: Short Guard interval should be used for this rate.
+ */
 enum mac80211_rate_control_flags {
 	IEEE80211_TX_RC_USE_RTS_CTS		= BIT(0),
 	IEEE80211_TX_RC_USE_CTS_PROTECT		= BIT(1),