rt2x00: FIF_PSPOLL filter flag support

This patch implements FIF_PSPOLL filter flag support in rt2x00 drivers,
which has been introduced in mac80211 (see
http://marc.info/?l=linux-wireless&m=124897986330807&w=2).

Signed-off-by: Igor Perminov <igor.perminov@inbox.ru>
Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/rt2x00/rt2x00mac.c b/drivers/net/wireless/rt2x00/rt2x00mac.c
index 74451f9..cb7b6d4 100644
--- a/drivers/net/wireless/rt2x00/rt2x00mac.c
+++ b/drivers/net/wireless/rt2x00/rt2x00mac.c
@@ -392,6 +392,7 @@
 	    FIF_FCSFAIL |
 	    FIF_PLCPFAIL |
 	    FIF_CONTROL |
+	    FIF_PSPOLL |
 	    FIF_OTHER_BSS |
 	    FIF_PROMISC_IN_BSS;
 
@@ -407,6 +408,22 @@
 		*total_flags |= FIF_PROMISC_IN_BSS | FIF_OTHER_BSS;
 
 	/*
+	 * If the device has a single filter for all control frames,
+	 * FIF_CONTROL and FIF_PSPOLL flags imply each other.
+	 * And if the device has more than one filter for control frames
+	 * of different types, but has no a separate filter for PS Poll frames,
+	 * FIF_CONTROL flag implies FIF_PSPOLL.
+	 */
+	if (!test_bit(DRIVER_SUPPORT_CONTROL_FILTERS, &rt2x00dev->flags)) {
+		if (*total_flags & FIF_CONTROL || *total_flags & FIF_PSPOLL)
+			*total_flags |= FIF_CONTROL | FIF_PSPOLL;
+	}
+	if (!test_bit(DRIVER_SUPPORT_CONTROL_FILTER_PSPOLL, &rt2x00dev->flags)) {
+		if (*total_flags & FIF_CONTROL)
+			*total_flags |= FIF_PSPOLL;
+	}
+
+	/*
 	 * Check if there is any work left for us.
 	 */
 	if (rt2x00dev->packet_filter == *total_flags)