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authorKim, Milo <Milo.Kim@ti.com>2013-02-20 00:36:01 -0800
committerBryan Wu <cooloney@gmail.com>2013-04-01 11:04:48 -0700
commitf07fb52107c881f35eaff09fe990a4dfd0f7e62a (patch)
treeb4b338f39799781648b5c6e0782c9ad746733bca /drivers/leds/trigger/ledtrig-heartbeat.c
parentff45262a85dbf1bc74463c5dcea1d71a406d4d8e (diff)
downloadlinux-f07fb52107c881f35eaff09fe990a4dfd0f7e62a.tar.bz2
leds: move LED trigger drivers into new subdirectory
For better driver management, new subdirectory, 'trigger' is created. All LED trigger drivers are moved into this directory. Internal header, 'leds.h' is included in each LED trigger drivers. Fix the location of header file, "leds.h" -> "../leds.h" in driver files. One exception is here, 'ledtrig-timer.c'. There is no need to include 'leds.h'. so '#include "leds.h"' line was removed. Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com> Signed-off-by: Bryan Wu <cooloney@gmail.com>
Diffstat (limited to 'drivers/leds/trigger/ledtrig-heartbeat.c')
-rw-r--r--drivers/leds/trigger/ledtrig-heartbeat.c161
1 files changed, 161 insertions, 0 deletions
diff --git a/drivers/leds/trigger/ledtrig-heartbeat.c b/drivers/leds/trigger/ledtrig-heartbeat.c
new file mode 100644
index 000000000000..5c8464a33172
--- /dev/null
+++ b/drivers/leds/trigger/ledtrig-heartbeat.c
@@ -0,0 +1,161 @@
+/*
+ * 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/slab.h>
+#include <linux/timer.h>
+#include <linux/sched.h>
+#include <linux/leds.h>
+#include <linux/reboot.h>
+#include "../leds.h"
+
+static int panic_heartbeats;
+
+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;
+
+ if (unlikely(panic_heartbeats)) {
+ led_set_brightness(led_cdev, LED_OFF);
+ return;
+ }
+
+ /* 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_cdev->max_brightness;
+ 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_cdev->max_brightness;
+ 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);
+ led_cdev->activated = true;
+}
+
+static void heartbeat_trig_deactivate(struct led_classdev *led_cdev)
+{
+ struct heartbeat_trig_data *heartbeat_data = led_cdev->trigger_data;
+
+ if (led_cdev->activated) {
+ del_timer_sync(&heartbeat_data->timer);
+ kfree(heartbeat_data);
+ led_cdev->activated = false;
+ }
+}
+
+static struct led_trigger heartbeat_led_trigger = {
+ .name = "heartbeat",
+ .activate = heartbeat_trig_activate,
+ .deactivate = heartbeat_trig_deactivate,
+};
+
+static int heartbeat_reboot_notifier(struct notifier_block *nb,
+ unsigned long code, void *unused)
+{
+ led_trigger_unregister(&heartbeat_led_trigger);
+ return NOTIFY_DONE;
+}
+
+static int heartbeat_panic_notifier(struct notifier_block *nb,
+ unsigned long code, void *unused)
+{
+ panic_heartbeats = 1;
+ return NOTIFY_DONE;
+}
+
+static struct notifier_block heartbeat_reboot_nb = {
+ .notifier_call = heartbeat_reboot_notifier,
+};
+
+static struct notifier_block heartbeat_panic_nb = {
+ .notifier_call = heartbeat_panic_notifier,
+};
+
+static int __init heartbeat_trig_init(void)
+{
+ int rc = led_trigger_register(&heartbeat_led_trigger);
+
+ if (!rc) {
+ atomic_notifier_chain_register(&panic_notifier_list,
+ &heartbeat_panic_nb);
+ register_reboot_notifier(&heartbeat_reboot_nb);
+ }
+ return rc;
+}
+
+static void __exit heartbeat_trig_exit(void)
+{
+ unregister_reboot_notifier(&heartbeat_reboot_nb);
+ atomic_notifier_chain_unregister(&panic_notifier_list,
+ &heartbeat_panic_nb);
+ 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");