mac80211: add throughput based LED blink trigger

iwlwifi and other drivers like to blink their LED
based on throughput. Implement this generically in
mac80211, based on a throughput table the driver
specifies. That way, drivers can set the blink
frequencies depending on their desired behaviour
and max throughput.

All the drivers need to do is provide an LED class
device, best with blink hardware offload.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

include/net/mac80211.h

@@ -1852,11 +1852,26 @@ struct ieee80211_hw *ieee80211_alloc_hw(size_t priv_data_len,
  */
 int ieee80211_register_hw(struct ieee80211_hw *hw);
 
+/**
+ * struct ieee80211_tpt_blink - throughput blink description
+ * @throughput: throughput in Kbit/sec
+ * @blink_time: blink time in milliseconds
+ *	(full cycle, ie. one off + one on period)
+ */
+struct ieee80211_tpt_blink {
+	int throughput;
+	int blink_time;
+};
+
 #ifdef CONFIG_MAC80211_LEDS
 extern char *__ieee80211_get_tx_led_name(struct ieee80211_hw *hw);
 extern char *__ieee80211_get_rx_led_name(struct ieee80211_hw *hw);
 extern char *__ieee80211_get_assoc_led_name(struct ieee80211_hw *hw);
 extern char *__ieee80211_get_radio_led_name(struct ieee80211_hw *hw);
+extern char *__ieee80211_create_tpt_led_trigger(
+				struct ieee80211_hw *hw,
+				const struct ieee80211_tpt_blink *blink_table,
+				unsigned int blink_table_len);
 #endif
 /**
  * ieee80211_get_tx_led_name - get name of TX LED
@@ -1934,6 +1949,29 @@ static inline char *ieee80211_get_radio_led_name(struct ieee80211_hw *hw)
 #endif
 }
 
+/**
+ * ieee80211_create_tpt_led_trigger - create throughput LED trigger
+ * @hw: the hardware to create the trigger for
+ * @blink_table: the blink table -- needs to be ordered by throughput
+ * @blink_table_len: size of the blink table
+ *
+ * This function returns %NULL (in case of error, or if no LED
+ * triggers are configured) or the name of the new trigger.
+ * This function must be called before ieee80211_register_hw().
+ */
+static inline char *
+ieee80211_create_tpt_led_trigger(struct ieee80211_hw *hw,
+				 const struct ieee80211_tpt_blink *blink_table,
+				 unsigned int blink_table_len)
+{
+#ifdef CONFIG_MAC80211_LEDS
+	return __ieee80211_create_tpt_led_trigger(hw, blink_table,
+						  blink_table_len);
+#else
+	return NULL;
+#endif
+}
+
 /**
  * ieee80211_unregister_hw - Unregister a hardware device
  *

net/mac80211/ieee80211_i.h

@@ -23,6 +23,7 @@
 #include <linux/types.h>
 #include <linux/spinlock.h>
 #include <linux/etherdevice.h>
+#include <linux/leds.h>
 #include <net/ieee80211_radiotap.h>
 #include <net/cfg80211.h>
 #include <net/mac80211.h>
@@ -630,6 +631,17 @@ enum queue_stop_reason {
 	IEEE80211_QUEUE_STOP_REASON_SKB_ADD,
 };
 
+struct tpt_led_trigger {
+	struct led_trigger trig;
+	char name[32];
+	const struct ieee80211_tpt_blink *blink_table;
+	unsigned int blink_table_len;
+	struct timer_list timer;
+	bool running;
+	unsigned long prev_traffic;
+	unsigned long tx_bytes, rx_bytes;
+};
+
 /**
  * mac80211 scan flags - currently active scan mode
  *
@@ -838,6 +850,7 @@ struct ieee80211_local {
 #ifdef CONFIG_MAC80211_LEDS
 	int tx_led_counter, rx_led_counter;
 	struct led_trigger *tx_led, *rx_led, *assoc_led, *radio_led;
+	struct tpt_led_trigger *tpt_led_trigger;
 	char tx_led_name[32], rx_led_name[32],
 	     assoc_led_name[32], radio_led_name[32];
 #endif

net/mac80211/iface.c

@@ -220,6 +220,7 @@ static int ieee80211_do_open(struct net_device *dev, bool coming_up)
 		/* we're brought up, everything changes */
 		hw_reconf_flags = ~0;
 		ieee80211_led_radio(local, true);
+		ieee80211_start_tpt_led_trig(local);
 	}
 
 	/*

net/mac80211/led.c

@@ -103,6 +103,13 @@ void ieee80211_led_init(struct ieee80211_local *local)
 			local->radio_led = NULL;
 		}
 	}
+
+	if (local->tpt_led_trigger) {
+		if (led_trigger_register(&local->tpt_led_trigger->trig)) {
+			kfree(local->tpt_led_trigger);
+			local->tpt_led_trigger = NULL;
+		}
+	}
 }
 
 void ieee80211_led_exit(struct ieee80211_local *local)
@@ -123,6 +130,11 @@ void ieee80211_led_exit(struct ieee80211_local *local)
 		led_trigger_unregister(local->rx_led);
 		kfree(local->rx_led);
 	}
+
+	if (local->tpt_led_trigger) {
+		led_trigger_unregister(&local->tpt_led_trigger->trig);
+		kfree(local->tpt_led_trigger);
+	}
 }
 
 char *__ieee80211_get_radio_led_name(struct ieee80211_hw *hw)
@@ -156,3 +168,112 @@ char *__ieee80211_get_rx_led_name(struct ieee80211_hw *hw)
 	return local->rx_led_name;
 }
 EXPORT_SYMBOL(__ieee80211_get_rx_led_name);
+
+static unsigned long tpt_trig_traffic(struct ieee80211_local *local,
+				      struct tpt_led_trigger *tpt_trig)
+{
+	unsigned long traffic, delta;
+
+	traffic = tpt_trig->tx_bytes + tpt_trig->rx_bytes;
+
+	delta = traffic - tpt_trig->prev_traffic;
+	tpt_trig->prev_traffic = traffic;
+	return DIV_ROUND_UP(delta, 1024 / 8);
+}
+
+static void tpt_trig_timer(unsigned long data)
+{
+	struct ieee80211_local *local = (void *)data;
+	struct tpt_led_trigger *tpt_trig = local->tpt_led_trigger;
+	struct led_classdev *led_cdev;
+	unsigned long on, off, tpt;
+	int i;
+
+	if (!tpt_trig->running)
+		return;
+
+	mod_timer(&tpt_trig->timer, round_jiffies(jiffies + HZ));
+
+	tpt = tpt_trig_traffic(local, tpt_trig);
+
+	/* default to just solid on */
+	on = 1;
+	off = 0;
+
+	for (i = tpt_trig->blink_table_len - 1; i >= 0; i--) {
+		if (tpt_trig->blink_table[i].throughput < 0 ||
+		    tpt > tpt_trig->blink_table[i].throughput) {
+			off = tpt_trig->blink_table[i].blink_time / 2;
+			on = tpt_trig->blink_table[i].blink_time - off;
+			break;
+		}
+	}
+
+	read_lock(&tpt_trig->trig.leddev_list_lock);
+	list_for_each_entry(led_cdev, &tpt_trig->trig.led_cdevs, trig_list)
+		led_blink_set(led_cdev, &on, &off);
+	read_unlock(&tpt_trig->trig.leddev_list_lock);
+}
+
+extern char *__ieee80211_create_tpt_led_trigger(
+				struct ieee80211_hw *hw,
+				const struct ieee80211_tpt_blink *blink_table,
+				unsigned int blink_table_len)
+{
+	struct ieee80211_local *local = hw_to_local(hw);
+	struct tpt_led_trigger *tpt_trig;
+
+	if (WARN_ON(local->tpt_led_trigger))
+		return NULL;
+
+	tpt_trig = kzalloc(sizeof(struct tpt_led_trigger), GFP_KERNEL);
+	if (!tpt_trig)
+		return NULL;
+
+	snprintf(tpt_trig->name, sizeof(tpt_trig->name),
+		 "%stpt", wiphy_name(local->hw.wiphy));
+
+	tpt_trig->trig.name = tpt_trig->name;
+
+	tpt_trig->blink_table = blink_table;
+	tpt_trig->blink_table_len = blink_table_len;
+
+	setup_timer(&tpt_trig->timer, tpt_trig_timer, (unsigned long)local);
+
+	local->tpt_led_trigger = tpt_trig;
+
+	return tpt_trig->name;
+}
+EXPORT_SYMBOL(__ieee80211_create_tpt_led_trigger);
+
+void ieee80211_start_tpt_led_trig(struct ieee80211_local *local)
+{
+	struct tpt_led_trigger *tpt_trig = local->tpt_led_trigger;
+
+	if (!tpt_trig)
+		return;
+
+	/* reset traffic */
+	tpt_trig_traffic(local, tpt_trig);
+	tpt_trig->running = true;
+
+	tpt_trig_timer((unsigned long)local);
+	mod_timer(&tpt_trig->timer, round_jiffies(jiffies + HZ));
+}
+
+void ieee80211_stop_tpt_led_trig(struct ieee80211_local *local)
+{
+	struct tpt_led_trigger *tpt_trig = local->tpt_led_trigger;
+	struct led_classdev *led_cdev;
+
+	if (!tpt_trig)
+		return;
+
+	tpt_trig->running = false;
+	del_timer_sync(&tpt_trig->timer);
+
+	read_lock(&tpt_trig->trig.leddev_list_lock);
+	list_for_each_entry(led_cdev, &tpt_trig->trig.led_cdevs, trig_list)
+		led_brightness_set(led_cdev, LED_OFF);
+	read_unlock(&tpt_trig->trig.leddev_list_lock);
+}

net/mac80211/led.h

@@ -12,15 +12,17 @@
 #include "ieee80211_i.h"
 
 #ifdef CONFIG_MAC80211_LEDS
-extern void ieee80211_led_rx(struct ieee80211_local *local);
-extern void ieee80211_led_tx(struct ieee80211_local *local, int q);
-extern void ieee80211_led_assoc(struct ieee80211_local *local,
-				bool associated);
-extern void ieee80211_led_radio(struct ieee80211_local *local,
-				bool enabled);
-extern void ieee80211_led_names(struct ieee80211_local *local);
-extern void ieee80211_led_init(struct ieee80211_local *local);
-extern void ieee80211_led_exit(struct ieee80211_local *local);
+void ieee80211_led_rx(struct ieee80211_local *local);
+void ieee80211_led_tx(struct ieee80211_local *local, int q);
+void ieee80211_led_assoc(struct ieee80211_local *local,
+			 bool associated);
+void ieee80211_led_radio(struct ieee80211_local *local,
+			 bool enabled);
+void ieee80211_led_names(struct ieee80211_local *local);
+void ieee80211_led_init(struct ieee80211_local *local);
+void ieee80211_led_exit(struct ieee80211_local *local);
+void ieee80211_start_tpt_led_trig(struct ieee80211_local *local);
+void ieee80211_stop_tpt_led_trig(struct ieee80211_local *local);
 #else
 static inline void ieee80211_led_rx(struct ieee80211_local *local)
 {
@@ -45,4 +47,28 @@ static inline void ieee80211_led_init(struct ieee80211_local *local)
 static inline void ieee80211_led_exit(struct ieee80211_local *local)
 {
 }
+static inline void ieee80211_start_tpt_led_trig(struct ieee80211_local *local)
+{
+}
+static inline void ieee80211_stop_tpt_led_trig(struct ieee80211_local *local)
+{
+}
+#endif
+
+static inline void
+ieee80211_tpt_led_trig_tx(struct ieee80211_local *local, __le16 fc, int bytes)
+{
+#ifdef CONFIG_MAC80211_LEDS
+	if (local->tpt_led_trigger && ieee80211_is_data(fc))
+		local->tpt_led_trigger->tx_bytes += bytes;
 #endif
+}
+
+static inline void
+ieee80211_tpt_led_trig_rx(struct ieee80211_local *local, __le16 fc, int bytes)
+{
+#ifdef CONFIG_MAC80211_LEDS
+	if (local->tpt_led_trigger && ieee80211_is_data(fc))
+		local->tpt_led_trigger->rx_bytes += bytes;
+#endif
+}

net/mac80211/rx.c

@@ -2928,6 +2928,9 @@ void ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb)
 		return;
 	}
 
+	ieee80211_tpt_led_trig_rx(local,
+			((struct ieee80211_hdr *)skb->data)->frame_control,
+			skb->len);
 	__ieee80211_rx_handle_packet(hw, skb);
 
 	rcu_read_unlock();

net/mac80211/tx.c

@@ -1297,6 +1297,7 @@ static int __ieee80211_tx(struct ieee80211_local *local,
 
 	while (skb) {
 		int q = skb_get_queue_mapping(skb);
+		__le16 fc;
 
 		spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
 		ret = IEEE80211_TX_OK;
@@ -1339,6 +1340,7 @@ static int __ieee80211_tx(struct ieee80211_local *local,
 		else
 			info->control.sta = NULL;
 
+		fc = ((struct ieee80211_hdr *)skb->data)->frame_control;
 		ret = drv_tx(local, skb);
 		if (WARN_ON(ret != NETDEV_TX_OK && skb->len != len)) {
 			dev_kfree_skb(skb);
@@ -1349,6 +1351,7 @@ static int __ieee80211_tx(struct ieee80211_local *local,
 			return IEEE80211_TX_AGAIN;
 		}
 
+		ieee80211_tpt_led_trig_tx(local, fc, len);
 		*skbp = skb = next;
 		ieee80211_led_tx(local, 1);
 		fragm = true;

net/mac80211/util.c

@@ -1116,6 +1116,7 @@ u32 ieee80211_sta_get_rates(struct ieee80211_local *local,
 void ieee80211_stop_device(struct ieee80211_local *local)
 {
 	ieee80211_led_radio(local, false);
+	ieee80211_stop_tpt_led_trig(local);
 
 	cancel_work_sync(&local->reconfig_filter);
 
@@ -1150,6 +1151,7 @@ int ieee80211_reconfig(struct ieee80211_local *local)
 		}
 
 		ieee80211_led_radio(local, true);
+		ieee80211_start_tpt_led_trig(local);
 	}
 
 	/* add interfaces */