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	Based on 2 normalized pattern(s): 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 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 # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Enrico Weigelt <info@metux.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
		
			
				
	
	
		
			73 lines
		
	
	
	
		
			1.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			73 lines
		
	
	
	
		
			1.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
// SPDX-License-Identifier: GPL-2.0-only
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/*
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 * Kernel Panic LED Trigger
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 *
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 * Copyright 2016 Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
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 */
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#include <linux/kernel.h>
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#include <linux/init.h>
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#include <linux/notifier.h>
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#include <linux/leds.h>
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#include "../leds.h"
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static struct led_trigger *trigger;
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/*
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 * This is called in a special context by the atomic panic
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 * notifier. This means the trigger can be changed without
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 * worrying about locking.
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 */
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static void led_trigger_set_panic(struct led_classdev *led_cdev)
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{
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	struct led_trigger *trig;
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	list_for_each_entry(trig, &trigger_list, next_trig) {
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		if (strcmp("panic", trig->name))
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			continue;
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		if (led_cdev->trigger)
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			list_del(&led_cdev->trig_list);
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		list_add_tail(&led_cdev->trig_list, &trig->led_cdevs);
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		/* Avoid the delayed blink path */
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		led_cdev->blink_delay_on = 0;
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		led_cdev->blink_delay_off = 0;
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		led_cdev->trigger = trig;
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		if (trig->activate)
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			trig->activate(led_cdev);
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		break;
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	}
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}
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static int led_trigger_panic_notifier(struct notifier_block *nb,
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				      unsigned long code, void *unused)
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{
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	struct led_classdev *led_cdev;
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	list_for_each_entry(led_cdev, &leds_list, node)
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		if (led_cdev->flags & LED_PANIC_INDICATOR)
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			led_trigger_set_panic(led_cdev);
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	return NOTIFY_DONE;
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}
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static struct notifier_block led_trigger_panic_nb = {
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	.notifier_call = led_trigger_panic_notifier,
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};
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static long led_panic_blink(int state)
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{
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	led_trigger_event(trigger, state ? LED_FULL : LED_OFF);
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	return 0;
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}
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static int __init ledtrig_panic_init(void)
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{
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	atomic_notifier_chain_register(&panic_notifier_list,
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				       &led_trigger_panic_nb);
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	led_trigger_register_simple("panic", &trigger);
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	panic_blink = led_panic_blink;
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	return 0;
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}
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device_initcall(ledtrig_panic_init);
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