Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  1) // SPDX-License-Identifier: GPL-2.0-only
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  3)  * Kernel Panic LED Trigger
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  4)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  5)  * Copyright 2016 Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  6)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  7) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  8) #include <linux/kernel.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  9) #include <linux/init.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) #include <linux/notifier.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) #include <linux/leds.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) #include "../leds.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) static struct led_trigger *trigger;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17)  * This is called in a special context by the atomic panic
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18)  * notifier. This means the trigger can be changed without
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19)  * worrying about locking.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) static void led_trigger_set_panic(struct led_classdev *led_cdev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) 	struct led_trigger *trig;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) 	list_for_each_entry(trig, &trigger_list, next_trig) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) 		if (strcmp("panic", trig->name))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) 			continue;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) 		if (led_cdev->trigger)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) 			list_del(&led_cdev->trig_list);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) 		list_add_tail(&led_cdev->trig_list, &trig->led_cdevs);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) 		/* Avoid the delayed blink path */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) 		led_cdev->blink_delay_on = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) 		led_cdev->blink_delay_off = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) 		led_cdev->trigger = trig;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) 		if (trig->activate)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) 			trig->activate(led_cdev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) 		break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) static int led_trigger_panic_notifier(struct notifier_block *nb,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) 				      unsigned long code, void *unused)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) 	struct led_classdev *led_cdev;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) 	list_for_each_entry(led_cdev, &leds_list, node)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) 		if (led_cdev->flags & LED_PANIC_INDICATOR)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) 			led_trigger_set_panic(led_cdev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) 	return NOTIFY_DONE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) static struct notifier_block led_trigger_panic_nb = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) 	.notifier_call = led_trigger_panic_notifier,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) static long led_panic_blink(int state)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) 	led_trigger_event(trigger, state ? LED_FULL : LED_OFF);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) static int __init ledtrig_panic_init(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) 	atomic_notifier_chain_register(&panic_notifier_list,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) 				       &led_trigger_panic_nb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) 	led_trigger_register_simple("panic", &trigger);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) 	panic_blink = led_panic_blink;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) device_initcall(ledtrig_panic_init);