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>

1 files changed, 100 insertions, 0 deletions

diff --git a/drivers/net/wireless/wl12xx/wl1271_main.c b/drivers/net/wireless/wl12xx/wl1271_main.c
index d6d1a4c1b114..7d70f4168b2f 100644
--- a/drivers/net/wireless/wl12xx/wl1271_main.c
+++ b/drivers/net/wireless/wl12xx/wl1271_main.c
@@ -32,6 +32,7 @@
 #include <linux/etherdevice.h>
 #include <linux/vmalloc.h>
 #include <linux/spi/wl12xx.h>
+#include <linux/inetdevice.h>
 
 #include "wl1271.h"
 #include "wl12xx_80211.h"
@@ -325,6 +326,8 @@ static struct conf_drv_settings default_conf = {
 	}
 };
 
+static LIST_HEAD(wl_list);
+
 static void wl1271_conf_init(struct wl1271 *wl)
 {
 
@@ -843,6 +846,93 @@ static int wl1271_op_tx(struct ieee80211_hw *hw, struct sk_buff *skb)
 	return NETDEV_TX_OK;
 }
 
+static int wl1271_dev_notify(struct notifier_block *me, unsigned long what,
+			     void *arg)
+{
+	struct net_device *dev;
+	struct wireless_dev *wdev;
+	struct wiphy *wiphy;
+	struct ieee80211_hw *hw;
+	struct wl1271 *wl;
+	struct wl1271 *wl_temp;
+	struct in_device *idev;
+	struct in_ifaddr *ifa = arg;
+	int ret = 0;
+
+	/* FIXME: this ugly function should probably be implemented in the
+	 * mac80211, and here should only be a simple callback handling actual
+	 * setting of the filters. Now we need to dig up references to
+	 * various structures to gain access to what we need.
+	 * Also, because of this, there is no "initial" setting of the filter
+	 * in "op_start", because we don't want to dig up struct net_device
+	 * there - the filter will be set upon first change of the interface
+	 * IP address. */
+
+	dev = ifa->ifa_dev->dev;
+
+	wdev = dev->ieee80211_ptr;
+	if (wdev == NULL)
+		return -ENODEV;
+
+	wiphy = wdev->wiphy;
+	if (wiphy == NULL)
+		return -ENODEV;
+
+	hw = wiphy_priv(wiphy);
+	if (hw == NULL)
+		return -ENODEV;
+
+	/* Check that the interface is one supported by this driver. */
+	wl_temp = hw->priv;
+	list_for_each_entry(wl, &wl_list, list) {
+		if (wl == wl_temp)
+			break;
+	}
+	if (wl == NULL)
+		return -ENODEV;
+
+	/* Get the interface IP address for the device. "ifa" will become
+	   NULL if:
+	     - there is no IPV4 protocol address configured
+	     - there are multiple (virtual) IPV4 addresses configured
+	   When "ifa" is NULL, filtering will be disabled.
+	*/
+	ifa = NULL;
+	idev = dev->ip_ptr;
+	if (idev)
+		ifa = idev->ifa_list;
+
+	if (ifa && ifa->ifa_next)
+		ifa = NULL;
+
+	mutex_lock(&wl->mutex);
+
+	if (wl->state == WL1271_STATE_OFF)
+		goto out;
+
+	ret = wl1271_ps_elp_wakeup(wl, false);
+	if (ret < 0)
+		goto out;
+	if (ifa)
+		ret = wl1271_acx_arp_ip_filter(wl, true,
+					       (u8 *)&ifa->ifa_address,
+					       ACX_IPV4_VERSION);
+	else
+		ret = wl1271_acx_arp_ip_filter(wl, false, NULL,
+					       ACX_IPV4_VERSION);
+	wl1271_ps_elp_sleep(wl);
+
+out:
+	mutex_unlock(&wl->mutex);
+
+	return ret;
+}
+
+static struct notifier_block wl1271_dev_notifier = {
+	.notifier_call = wl1271_dev_notify,
+};
+
+
 static int wl1271_op_start(struct ieee80211_hw *hw)
 {
 	struct wl1271 *wl = hw->priv;
@@ -886,6 +976,11 @@ out_power_off:
 out:
 	mutex_unlock(&wl->mutex);
 
+	if (!ret) {
+		list_add(&wl->list, &wl_list);
+		register_inetaddr_notifier(&wl1271_dev_notifier);
+	}
+
 	return ret;
 }
 
@@ -906,6 +1001,9 @@ static void wl1271_op_stop(struct ieee80211_hw *hw)
 	wl->filter_params = NULL;
 	spin_unlock_irqrestore(&wl->wl_lock, flags);
 
+	unregister_inetaddr_notifier(&wl1271_dev_notifier);
+	list_del(&wl->list);
+
 	mutex_lock(&wl->mutex);
 
 	WARN_ON(wl->state != WL1271_STATE_ON);
@@ -1754,6 +1852,8 @@ static int __devinit wl1271_probe(struct spi_device *spi)
 	wl = hw->priv;
 	memset(wl, 0, sizeof(*wl));
 
+	INIT_LIST_HEAD(&wl->list);
+
 	wl->hw = hw;
 	dev_set_drvdata(&spi->dev, wl);
 	wl->spi = spi;