[PATCH] LED: add LED heartbeat trigger

[PATCH] LED: add LED heartbeat trigger

[Atsushi Nemoto]

Add an LED trigger acts like a heart beat.  This can be used as a
replacement of CONFIG_HEARTBEAT code exists in some arch's timer code.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>

diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
index 6265062..21bb7e8 100644
--- a/drivers/leds/Kconfig
+++ b/drivers/leds/Kconfig
@@ -87,5 +87,14 @@ config LEDS_TRIGGER_IDE_DISK
 	  This allows LEDs to be controlled by IDE disk activity.
 	  If unsure, say Y.
 
+config LEDS_TRIGGER_HEARTBEAT
+	tristate "LED Heartbeat Trigger"
+	depends LEDS_TRIGGERS
+	help
+	  This allows LEDs to be controlled by a CPU load average.
+	  The flash frequency is a hyperbolic function of the 5-minute
+	  load average.
+	  If unsure, say Y.
+
 endmenu
 
diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
index 40f0426..1dc79b5 100644
--- a/drivers/leds/Makefile
+++ b/drivers/leds/Makefile
@@ -15,3 +15,4 @@ obj-$(CONFIG_LEDS_S3C24XX)		+= leds-s3c2
 # LED Triggers
 obj-$(CONFIG_LEDS_TRIGGER_TIMER)	+= ledtrig-timer.o
 obj-$(CONFIG_LEDS_TRIGGER_IDE_DISK)	+= ledtrig-ide-disk.o
+obj-$(CONFIG_LEDS_TRIGGER_HEARTBEAT)	+= ledtrig-heartbeat.o
diff --git a/drivers/leds/ledtrig-heartbeat.c b/drivers/leds/ledtrig-heartbeat.c
new file mode 100644
index 0000000..07ac645
--- /dev/null
+++ b/drivers/leds/ledtrig-heartbeat.c
@@ -0,0 +1,118 @@
+/*
+ * LED Heartbeat Trigger
+ *
+ * Copyright (C) 2006 Atsushi Nemoto <anemo@mba.ocn.ne.jp>
+ *
+ * Based on Richard Purdie's ledtrig-timer.c and some arch's
+ * CONFIG_HEARTBEAT code.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/timer.h>
+#include <linux/sched.h>
+#include <linux/leds.h>
+#include "leds.h"
+
+struct heartbeat_trig_data {
+	unsigned int phase;
+	unsigned int period;
+	struct timer_list timer;
+};
+
+static void led_heartbeat_function(unsigned long data)
+{
+	struct led_classdev *led_cdev = (struct led_classdev *) data;
+	struct heartbeat_trig_data *heartbeat_data = led_cdev->trigger_data;
+	unsigned long brightness = LED_OFF;
+	unsigned long delay = 0;
+
+	/* acts like an actual heart beat -- ie thump-thump-pause... */
+	switch (heartbeat_data->phase) {
+	case 0:
+		/*
+		 * The hyperbolic function below modifies the
+		 * heartbeat period length in dependency of the
+		 * current (5min) load. It goes through the points
+		 * f(0)=126, f(1)=86, f(5)=51, f(inf)->30.
+		 */
+		heartbeat_data->period = 30 +
+			(672 << FSHIFT) / (5 * avenrun[0] + (7 << FSHIFT));
+		heartbeat_data->period = heartbeat_data->period * HZ / 100;
+		delay = 7 * HZ / 100;
+		heartbeat_data->phase++;
+		brightness = LED_FULL;
+		break;
+	case 1:
+		delay = heartbeat_data->period / 4 - 7 * HZ / 100;
+		heartbeat_data->phase++;
+		break;
+	case 2:
+		delay = 7 * HZ / 100;
+		heartbeat_data->phase++;
+		brightness = LED_FULL;
+		break;
+	default:
+		delay = heartbeat_data->period - heartbeat_data->period / 4 -
+			7 * HZ / 100;
+		heartbeat_data->phase = 0;
+		break;
+	}
+
+	led_set_brightness(led_cdev, brightness);
+	mod_timer(&heartbeat_data->timer, jiffies + delay);
+}
+
+static void heartbeat_trig_activate(struct led_classdev *led_cdev)
+{
+	struct heartbeat_trig_data *heartbeat_data;
+
+	heartbeat_data = kzalloc(sizeof(*heartbeat_data), GFP_KERNEL);
+	if (!heartbeat_data)
+		return;
+
+	led_cdev->trigger_data = heartbeat_data;
+	init_timer(&heartbeat_data->timer);
+	heartbeat_data->timer.function = led_heartbeat_function;
+	heartbeat_data->timer.data = (unsigned long) led_cdev;
+	heartbeat_data->phase = 0;
+	led_heartbeat_function(heartbeat_data->timer.data);
+}
+
+static void heartbeat_trig_deactivate(struct led_classdev *led_cdev)
+{
+	struct heartbeat_trig_data *heartbeat_data = led_cdev->trigger_data;
+
+	if (heartbeat_data) {
+		del_timer_sync(&heartbeat_data->timer);
+		kfree(heartbeat_data);
+	}
+}
+
+static struct led_trigger heartbeat_led_trigger = {
+	.name     = "heartbeat",
+	.activate = heartbeat_trig_activate,
+	.deactivate = heartbeat_trig_deactivate,
+};
+
+static int __init heartbeat_trig_init(void)
+{
+	return led_trigger_register(&heartbeat_led_trigger);
+}
+
+static void __exit heartbeat_trig_exit(void)
+{
+	led_trigger_unregister(&heartbeat_led_trigger);
+}
+
+module_init(heartbeat_trig_init);
+module_exit(heartbeat_trig_exit);
+
+MODULE_AUTHOR("Atsushi Nemoto <anemo@mba.ocn.ne.jp>");
+MODULE_DESCRIPTION("Heartbeat LED trigger");
+MODULE_LICENSE("GPL");

Re: [PATCH] LED: add LED heartbeat trigger

[Nish Aravamudan]

On 6/20/06, Atsushi Nemoto <anemo@mba.ocn.ne.jp> wrote:
> Add an LED trigger acts like a heart beat.  This can be used as a
> replacement of CONFIG_HEARTBEAT code exists in some arch's timer code.
>
> Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>

<snip>

> new file mode 100644
> index 0000000..07ac645
> --- /dev/null
> +++ b/drivers/leds/ledtrig-heartbeat.c
> +               heartbeat_data->period = heartbeat_data->period * HZ / 100;
> +               delay = 7 * HZ / 100;

Can these and the other HZ/100 users make use of the existing
*secs_to_jiffies() methods? FYI, if HZ=250, you're getting rounding
here, not sure if it's desired.

<snip>

> +static void heartbeat_trig_activate(struct led_classdev *led_cdev)
> +{
> +       struct heartbeat_trig_data *heartbeat_data;
> +
> +       heartbeat_data = kzalloc(sizeof(*heartbeat_data), GFP_KERNEL);
> +       if (!heartbeat_data)
> +               return;
> +
> +       led_cdev->trigger_data = heartbeat_data;
> +       init_timer(&heartbeat_data->timer);
> +       heartbeat_data->timer.function = led_heartbeat_function;
> +       heartbeat_data->timer.data = (unsigned long) led_cdev;

setup_timer()? (which will call init_timer() before returning.

Thanks,
Nish

Re: [PATCH] LED: add LED heartbeat trigger

[Atsushi Nemoto]

On Tue, 20 Jun 2006 09:54:59 -0700, "Nish Aravamudan" <nish.aravamudan@gmail.com> wrote:
> Can these and the other HZ/100 users make use of the existing
> *secs_to_jiffies() methods? FYI, if HZ=250, you're getting rounding
> here, not sure if it's desired.

Thanks.  The msecs_to_jiffies makes code more readable.  The rounding
is not serious here.

> setup_timer()? (which will call init_timer() before returning.

Sure.  I'll post a new patch soon.

---
Atsushi Nemoto

Re: [PATCH] LED: add LED heartbeat trigger

[Atsushi Nemoto]

Take 2.  Updated by a few comment.  Thanks.


Add an LED trigger acts like a heart beat.  This can be used as a
replacement of CONFIG_HEARTBEAT code exists in some arch's timer code.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>

diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
index 6265062..b0d73b8 100644
--- a/drivers/leds/Kconfig
+++ b/drivers/leds/Kconfig
@@ -87,5 +87,14 @@ config LEDS_TRIGGER_IDE_DISK
 	  This allows LEDs to be controlled by IDE disk activity.
 	  If unsure, say Y.
 
+config LEDS_TRIGGER_HEARTBEAT
+	tristate "LED Heartbeat Trigger"
+	depends LEDS_TRIGGERS
+	help
+	  This allows LEDs to be controlled by a CPU load average.
+	  The flash frequency is a hyperbolic function of the 1-minute
+	  load average.
+	  If unsure, say Y.
+
 endmenu
 
diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
index 40f0426..1dc79b5 100644
--- a/drivers/leds/Makefile
+++ b/drivers/leds/Makefile
@@ -15,3 +15,4 @@ obj-$(CONFIG_LEDS_S3C24XX)		+= leds-s3c2
 # LED Triggers
 obj-$(CONFIG_LEDS_TRIGGER_TIMER)	+= ledtrig-timer.o
 obj-$(CONFIG_LEDS_TRIGGER_IDE_DISK)	+= ledtrig-ide-disk.o
+obj-$(CONFIG_LEDS_TRIGGER_HEARTBEAT)	+= ledtrig-heartbeat.o
diff --git a/drivers/leds/ledtrig-heartbeat.c b/drivers/leds/ledtrig-heartbeat.c
new file mode 100644
index 0000000..4bf8cec
--- /dev/null
+++ b/drivers/leds/ledtrig-heartbeat.c
@@ -0,0 +1,118 @@
+/*
+ * LED Heartbeat Trigger
+ *
+ * Copyright (C) 2006 Atsushi Nemoto <anemo@mba.ocn.ne.jp>
+ *
+ * Based on Richard Purdie's ledtrig-timer.c and some arch's
+ * CONFIG_HEARTBEAT code.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/timer.h>
+#include <linux/sched.h>
+#include <linux/leds.h>
+#include "leds.h"
+
+struct heartbeat_trig_data {
+	unsigned int phase;
+	unsigned int period;
+	struct timer_list timer;
+};
+
+static void led_heartbeat_function(unsigned long data)
+{
+	struct led_classdev *led_cdev = (struct led_classdev *) data;
+	struct heartbeat_trig_data *heartbeat_data = led_cdev->trigger_data;
+	unsigned long brightness = LED_OFF;
+	unsigned long delay = 0;
+
+	/* acts like an actual heart beat -- ie thump-thump-pause... */
+	switch (heartbeat_data->phase) {
+	case 0:
+		/*
+		 * The hyperbolic function below modifies the
+		 * heartbeat period length in dependency of the
+		 * current (1min) load. It goes through the points
+		 * f(0)=1260, f(1)=860, f(5)=510, f(inf)->300.
+		 */
+		heartbeat_data->period = 300 +
+			(6720 << FSHIFT) / (5 * avenrun[0] + (7 << FSHIFT));
+		heartbeat_data->period =
+			msecs_to_jiffies(heartbeat_data->period);
+		delay = msecs_to_jiffies(70);
+		heartbeat_data->phase++;
+		brightness = LED_FULL;
+		break;
+	case 1:
+		delay = heartbeat_data->period / 4 - msecs_to_jiffies(70);
+		heartbeat_data->phase++;
+		break;
+	case 2:
+		delay = msecs_to_jiffies(70);
+		heartbeat_data->phase++;
+		brightness = LED_FULL;
+		break;
+	default:
+		delay = heartbeat_data->period - heartbeat_data->period / 4 -
+			msecs_to_jiffies(70);
+		heartbeat_data->phase = 0;
+		break;
+	}
+
+	led_set_brightness(led_cdev, brightness);
+	mod_timer(&heartbeat_data->timer, jiffies + delay);
+}
+
+static void heartbeat_trig_activate(struct led_classdev *led_cdev)
+{
+	struct heartbeat_trig_data *heartbeat_data;
+
+	heartbeat_data = kzalloc(sizeof(*heartbeat_data), GFP_KERNEL);
+	if (!heartbeat_data)
+		return;
+
+	led_cdev->trigger_data = heartbeat_data;
+	setup_timer(&heartbeat_data->timer,
+		    led_heartbeat_function, (unsigned long) led_cdev);
+	heartbeat_data->phase = 0;
+	led_heartbeat_function(heartbeat_data->timer.data);
+}
+
+static void heartbeat_trig_deactivate(struct led_classdev *led_cdev)
+{
+	struct heartbeat_trig_data *heartbeat_data = led_cdev->trigger_data;
+
+	if (heartbeat_data) {
+		del_timer_sync(&heartbeat_data->timer);
+		kfree(heartbeat_data);
+	}
+}
+
+static struct led_trigger heartbeat_led_trigger = {
+	.name     = "heartbeat",
+	.activate = heartbeat_trig_activate,
+	.deactivate = heartbeat_trig_deactivate,
+};
+
+static int __init heartbeat_trig_init(void)
+{
+	return led_trigger_register(&heartbeat_led_trigger);
+}
+
+static void __exit heartbeat_trig_exit(void)
+{
+	led_trigger_unregister(&heartbeat_led_trigger);
+}
+
+module_init(heartbeat_trig_init);
+module_exit(heartbeat_trig_exit);
+
+MODULE_AUTHOR("Atsushi Nemoto <anemo@mba.ocn.ne.jp>");
+MODULE_DESCRIPTION("Heartbeat LED trigger");
+MODULE_LICENSE("GPL");

Re: [PATCH] LED: add LED heartbeat trigger

[Richard Purdie]

On Thu, 2006-06-22 at 00:01 +0900, Atsushi Nemoto wrote:
> Add an LED trigger acts like a heart beat.  This can be used as a
> replacement of CONFIG_HEARTBEAT code exists in some arch's timer code.
> 
> Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Acked-by: Richard Purdie <rpurdie@rpsys.net>

Re: [PATCH] LED: add LED heartbeat trigger

[Bodo Eggert]

Atsushi Nemoto <anemo@mba.ocn.ne.jp> wrote:

> +       This allows LEDs to be controlled by a CPU load average.
> +       The flash frequency is a hyperbolic function of the 5-minute
> +       load average.
> +       If unsure, say Y.

Wouldn't the 1-minute-load be better?
-- 
Ich danke GMX dafür, die Verwendung meiner Adressen mittels per SPF
verbreiteten Lügen zu sabotieren.

http://david.woodhou.se/why-not-spf.html

Re: [PATCH] LED: add LED heartbeat trigger

[Atsushi Nemoto]

On Tue, 20 Jun 2006 19:39:04 +0200, Bodo Eggert <7eggert@elstempel.de> wrote:
> > +       This allows LEDs to be controlled by a CPU load average.
> > +       The flash frequency is a hyperbolic function of the 5-minute
> > +       load average.
> > +       If unsure, say Y.
> 
> Wouldn't the 1-minute-load be better?

Actually, this driver (and preceeding CONFIG_HEARTBEAT codes) is using
1-minute load average, avenrun[0].  This inconsistency has been exist
so long time (since 2.4 kernel at least).  I'll fix the help text and
a comment in driver anyway.

---
Atsushi Nemoto