cregit-Linux how code gets into the kernel

Release 4.7 drivers/leds/trigger/ledtrig-heartbeat.c

/*
 * 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 <linux/suspend.h>
#include "../leds.h"


static int panic_heartbeats;


struct heartbeat_trig_data {
	
unsigned int phase;
	
unsigned int period;
	
struct timer_list timer;
	
unsigned int invert;
};


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_nosleep(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++; if (!heartbeat_data->invert) brightness = led_cdev->max_brightness; break; case 1: delay = heartbeat_data->period / 4 - msecs_to_jiffies(70); heartbeat_data->phase++; if (heartbeat_data->invert) brightness = led_cdev->max_brightness; break; case 2: delay = msecs_to_jiffies(70); heartbeat_data->phase++; if (!heartbeat_data->invert) brightness = led_cdev->max_brightness; break; default: delay = heartbeat_data->period - heartbeat_data->period / 4 - msecs_to_jiffies(70); heartbeat_data->phase = 0; if (heartbeat_data->invert) brightness = led_cdev->max_brightness; break; } led_set_brightness_nosleep(led_cdev, brightness); mod_timer(&heartbeat_data->timer, jiffies + delay); }

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PersonTokensPropCommitsCommitProp
atsushi nemotoatsushi nemoto19475.78%120.00%
jiri prchaljiri prchal3814.84%120.00%
alexander holleralexander holler166.25%120.00%
guennadi liakhovetskiguennadi liakhovetski62.34%120.00%
jacek anaszewskijacek anaszewski20.78%120.00%
Total256100.00%5100.00%


static ssize_t led_invert_show(struct device *dev, struct device_attribute *attr, char *buf) { struct led_classdev *led_cdev = dev_get_drvdata(dev); struct heartbeat_trig_data *heartbeat_data = led_cdev->trigger_data; return sprintf(buf, "%u\n", heartbeat_data->invert); }

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jiri prchaljiri prchal51100.00%1100.00%
Total51100.00%1100.00%


static ssize_t led_invert_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t size) { struct led_classdev *led_cdev = dev_get_drvdata(dev); struct heartbeat_trig_data *heartbeat_data = led_cdev->trigger_data; unsigned long state; int ret; ret = kstrtoul(buf, 0, &state); if (ret) return ret; heartbeat_data->invert = !!state; return size; }

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jiri prchaljiri prchal80100.00%1100.00%
Total80100.00%1100.00%

static DEVICE_ATTR(invert, 0644, led_invert_show, led_invert_store);
static void heartbeat_trig_activate(struct led_classdev *led_cdev) { struct heartbeat_trig_data *heartbeat_data; int rc; heartbeat_data = kzalloc(sizeof(*heartbeat_data), GFP_KERNEL); if (!heartbeat_data) return; led_cdev->trigger_data = heartbeat_data; rc = device_create_file(led_cdev->dev, &dev_attr_invert); if (rc) { kfree(led_cdev->trigger_data); return; } 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; }

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atsushi nemotoatsushi nemoto7267.29%133.33%
jiri prchaljiri prchal2927.10%133.33%
shuah khanshuah khan65.61%133.33%
Total107100.00%3100.00%


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); device_remove_file(led_cdev->dev, &dev_attr_invert); kfree(heartbeat_data); led_cdev->activated = false; } }

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atsushi nemotoatsushi nemoto3866.67%133.33%
jiri prchaljiri prchal1017.54%133.33%
shuah khanshuah khan915.79%133.33%
Total57100.00%3100.00%

static struct led_trigger heartbeat_led_trigger = { .name = "heartbeat", .activate = heartbeat_trig_activate, .deactivate = heartbeat_trig_deactivate, };
static int heartbeat_pm_notifier(struct notifier_block *nb, unsigned long pm_event, void *unused) { int rc; switch (pm_event) { case PM_SUSPEND_PREPARE: case PM_HIBERNATION_PREPARE: case PM_RESTORE_PREPARE: led_trigger_unregister(&heartbeat_led_trigger); break; case PM_POST_SUSPEND: case PM_POST_HIBERNATION: case PM_POST_RESTORE: rc = led_trigger_register(&heartbeat_led_trigger); if (rc) pr_err("could not re-register heartbeat trigger\n"); break; default: break; } return NOTIFY_DONE; }

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linus walleijlinus walleij76100.00%1100.00%
Total76100.00%1100.00%


static int heartbeat_reboot_notifier(struct notifier_block *nb, unsigned long code, void *unused) { led_trigger_unregister(&heartbeat_led_trigger); return NOTIFY_DONE; }

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alexander holleralexander holler28100.00%1100.00%
Total28100.00%1100.00%


static int heartbeat_panic_notifier(struct notifier_block *nb, unsigned long code, void *unused) { panic_heartbeats = 1; return NOTIFY_DONE; }

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alexander holleralexander holler26100.00%1100.00%
Total26100.00%1100.00%

static struct notifier_block heartbeat_pm_nb = { .notifier_call = heartbeat_pm_notifier, }; 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); register_pm_notifier(&heartbeat_pm_nb); } return rc; }

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alexander holleralexander holler2857.14%133.33%
atsushi nemotoatsushi nemoto1530.61%133.33%
linus walleijlinus walleij612.24%133.33%
Total49100.00%3100.00%


static void __exit heartbeat_trig_exit(void) { unregister_pm_notifier(&heartbeat_pm_nb); unregister_reboot_notifier(&heartbeat_reboot_nb); atomic_notifier_chain_unregister(&panic_notifier_list, &heartbeat_panic_nb); led_trigger_unregister(&heartbeat_led_trigger); }

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alexander holleralexander holler1541.67%133.33%
atsushi nemotoatsushi nemoto1541.67%133.33%
linus walleijlinus walleij616.67%133.33%
Total36100.00%3100.00%

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");

Overall Contributors

PersonTokensPropCommitsCommitProp
atsushi nemotoatsushi nemoto41945.69%110.00%
jiri prchaljiri prchal22424.43%110.00%
alexander holleralexander holler14415.70%220.00%
linus walleijlinus walleij10311.23%110.00%
shuah khanshuah khan151.64%110.00%
guennadi liakhovetskiguennadi liakhovetski60.65%110.00%
tejun heotejun heo30.33%110.00%
jacek anaszewskijacek anaszewski20.22%110.00%
kim milokim milo10.11%110.00%
Total917100.00%10100.00%
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