wl1271: Support for IPv4 ARP filtering

Add support for IPv4 ARP filtering in the driver. This will dramatically
reduce the number of unnecessary interrupts by the device in conqested
networks.

This patch is based on a similar patch to wl1251 by Janne Ylälehto.

Cc: Janne Ylälehto <janne.ylalehto@nokia.com>
Signed-off-by: Juuso Oikarinen <juuso.oikarinen@nokia.com>
Reviewed-by: Luciano Coelho <luciano.coelho@nokia.com>
Signed-off-by: Luciano Coelho <luciano.coelho@nokia.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/wl12xx/wl1271_acx.h b/drivers/net/wireless/wl12xx/wl1271_acx.h
index 29fd363..1580314 100644
--- a/drivers/net/wireless/wl12xx/wl1271_acx.h
+++ b/drivers/net/wireless/wl12xx/wl1271_acx.h
@@ -955,6 +955,21 @@
 	u8 padding[2];
 } __attribute__ ((packed));
 
+#define ACX_IPV4_VERSION 4
+#define ACX_IPV6_VERSION 6
+#define ACX_IPV4_ADDR_SIZE 4
+struct wl1271_acx_arp_filter {
+	struct acx_header header;
+	u8 version;         /* ACX_IPV4_VERSION, ACX_IPV6_VERSION */
+	u8 enable;          /* 1 to enable ARP filtering, 0 to disable */
+	u8 padding[2];
+	u8 address[16];     /* The configured device IP address - all ARP
+			       requests directed to this IP address will pass
+			       through. For IPv4, the first four bytes are
+			       used. */
+} __attribute__((packed));
+
+
 enum {
 	ACX_WAKE_UP_CONDITIONS      = 0x0002,
 	ACX_MEM_CFG                 = 0x0003,
@@ -1064,5 +1079,7 @@
 int wl1271_acx_init_rx_interrupt(struct wl1271 *wl);
 int wl1271_acx_smart_reflex(struct wl1271 *wl);
 int wl1271_acx_bet_enable(struct wl1271 *wl, bool enable);
+int wl1271_acx_arp_ip_filter(struct wl1271 *wl, bool enable, u8 *address,
+			     u8 version);
 
 #endif /* __WL1271_ACX_H__ */