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/rt73usb.c b/drivers/net/wireless/rt2x00/rt73usb.c
index 4f9b177..4b9955b 100644
--- a/drivers/net/wireless/rt2x00/rt73usb.c
+++ b/drivers/net/wireless/rt2x00/rt73usb.c
@@ -493,7 +493,7 @@
 	rt2x00_set_field32(&reg, TXRX_CSR0_DROP_PHYSICAL,
 			   !(filter_flags & FIF_PLCPFAIL));
 	rt2x00_set_field32(&reg, TXRX_CSR0_DROP_CONTROL,
-			   !(filter_flags & FIF_CONTROL));
+			   !(filter_flags & (FIF_CONTROL | FIF_PSPOLL)));
 	rt2x00_set_field32(&reg, TXRX_CSR0_DROP_NOT_TO_ME,
 			   !(filter_flags & FIF_PROMISC_IN_BSS));
 	rt2x00_set_field32(&reg, TXRX_CSR0_DROP_TO_DS,
@@ -2144,6 +2144,12 @@
 		return retval;
 
 	/*
+	 * This device has multiple filters for control frames,
+	 * but has no a separate filter for PS Poll frames.
+	 */
+	__set_bit(DRIVER_SUPPORT_CONTROL_FILTERS, &rt2x00dev->flags);
+
+	/*
 	 * This device requires firmware.
 	 */
 	__set_bit(DRIVER_REQUIRE_FIRMWARE, &rt2x00dev->flags);