linux/drivers/leds/trigger/ledtrig-panic.c
Andy Shevchenko f39650de68 kernel.h: split out panic and oops helpers
kernel.h is being used as a dump for all kinds of stuff for a long time.
Here is the attempt to start cleaning it up by splitting out panic and
oops helpers.

There are several purposes of doing this:
- dropping dependency in bug.h
- dropping a loop by moving out panic_notifier.h
- unload kernel.h from something which has its own domain

At the same time convert users tree-wide to use new headers, although for
the time being include new header back to kernel.h to avoid twisted
indirected includes for existing users.

[akpm@linux-foundation.org: thread_info.h needs limits.h]
[andriy.shevchenko@linux.intel.com: ia64 fix]
  Link: https://lkml.kernel.org/r/20210520130557.55277-1-andriy.shevchenko@linux.intel.com

Link: https://lkml.kernel.org/r/20210511074137.33666-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Co-developed-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Corey Minyard <cminyard@mvista.com>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Wei Liu <wei.liu@kernel.org>
Acked-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Sebastian Reichel <sre@kernel.org>
Acked-by: Luis Chamberlain <mcgrof@kernel.org>
Acked-by: Stephen Boyd <sboyd@kernel.org>
Acked-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Acked-by: Helge Deller <deller@gmx.de> # parisc
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-07-01 11:06:04 -07:00

75 lines
1.7 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Kernel Panic LED Trigger
*
* Copyright 2016 Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/notifier.h>
#include <linux/panic_notifier.h>
#include <linux/leds.h>
#include "../leds.h"
static struct led_trigger *trigger;
/*
* This is called in a special context by the atomic panic
* notifier. This means the trigger can be changed without
* worrying about locking.
*/
static void led_trigger_set_panic(struct led_classdev *led_cdev)
{
struct led_trigger *trig;
list_for_each_entry(trig, &trigger_list, next_trig) {
if (strcmp("panic", trig->name))
continue;
if (led_cdev->trigger)
list_del(&led_cdev->trig_list);
list_add_tail(&led_cdev->trig_list, &trig->led_cdevs);
/* Avoid the delayed blink path */
led_cdev->blink_delay_on = 0;
led_cdev->blink_delay_off = 0;
led_cdev->trigger = trig;
if (trig->activate)
trig->activate(led_cdev);
break;
}
}
static int led_trigger_panic_notifier(struct notifier_block *nb,
unsigned long code, void *unused)
{
struct led_classdev *led_cdev;
list_for_each_entry(led_cdev, &leds_list, node)
if (led_cdev->flags & LED_PANIC_INDICATOR)
led_trigger_set_panic(led_cdev);
return NOTIFY_DONE;
}
static struct notifier_block led_trigger_panic_nb = {
.notifier_call = led_trigger_panic_notifier,
};
static long led_panic_blink(int state)
{
led_trigger_event(trigger, state ? LED_FULL : LED_OFF);
return 0;
}
static int __init ledtrig_panic_init(void)
{
atomic_notifier_chain_register(&panic_notifier_list,
&led_trigger_panic_nb);
led_trigger_register_simple("panic", &trigger);
panic_blink = led_panic_blink;
return 0;
}
device_initcall(ledtrig_panic_init);