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>
diff --git a/net/mac80211/led.c b/net/mac80211/led.c
index 740a1d4..79b1309 100644
--- a/net/mac80211/led.c
+++ b/net/mac80211/led.c
@@ -103,6 +103,13 @@
 			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 @@
 		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 @@
 	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);
+}