[PATCH 1/3] leds:triggers:Extend the kernel panic LED trigger

From: chaochao2021666
Date: Mon Sep 06 2021 - 09:55:09 EST


From: chao zeng <chao.zeng@xxxxxxxxxxx>

This commit extend panic trigger, add two new panic trigger
"panic_on" and "panic_off" and keep the "panic" compatible with
"panic_blink".

All the led on the "panic_on" would light and on
the "panic_off" would turn off

Expand the panic state of led to meet more requirements

Signed-off-by: chao zeng <chao.zeng@xxxxxxxxxxx>
---
drivers/leds/trigger/ledtrig-panic.c | 39 ++++++++++++++++++++++------
1 file changed, 31 insertions(+), 8 deletions(-)

diff --git a/drivers/leds/trigger/ledtrig-panic.c b/drivers/leds/trigger/ledtrig-panic.c
index 64abf2e91608..1274bc94b5dd 100644
--- a/drivers/leds/trigger/ledtrig-panic.c
+++ b/drivers/leds/trigger/ledtrig-panic.c
@@ -12,19 +12,26 @@
#include <linux/leds.h>
#include "../leds.h"

-static struct led_trigger *trigger;
+enum led_display_type {
+ ON,
+ OFF,
+ BLINK,
+ DISPLAY_TYPE_COUNT,
+};
+
+static struct led_trigger *panic_trigger[DISPLAY_TYPE_COUNT];

/*
* 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)
+static void led_trigger_set_panic(struct led_classdev *led_cdev, const char *type)
{
struct led_trigger *trig;

list_for_each_entry(trig, &trigger_list, next_trig) {
- if (strcmp("panic", trig->name))
+ if (strcmp(type, trig->name))
continue;
if (led_cdev->trigger)
list_del(&led_cdev->trig_list);
@@ -37,6 +44,10 @@ static void led_trigger_set_panic(struct led_classdev *led_cdev)
led_cdev->trigger = trig;
if (trig->activate)
trig->activate(led_cdev);
+
+ /*Clear current brightness work*/
+ led_cdev->work_flags = 0;
+
break;
}
}
@@ -48,7 +59,12 @@ static int led_trigger_panic_notifier(struct notifier_block *nb,

list_for_each_entry(led_cdev, &leds_list, node)
if (led_cdev->flags & LED_PANIC_INDICATOR)
- led_trigger_set_panic(led_cdev);
+ led_trigger_set_panic(led_cdev, "panic");
+ else if (led_cdev->flags & LED_PANIC_INDICATOR_ON)
+ led_trigger_set_panic(led_cdev, "panic_on");
+ else if (led_cdev->flags & LED_PANIC_INDICATOR_OFF)
+ led_trigger_set_panic(led_cdev, "panic_off");
+
return NOTIFY_DONE;
}

@@ -56,9 +72,12 @@ static struct notifier_block led_trigger_panic_nb = {
.notifier_call = led_trigger_panic_notifier,
};

-static long led_panic_blink(int state)
+static long led_panic_activity(int state)
{
- led_trigger_event(trigger, state ? LED_FULL : LED_OFF);
+ led_trigger_event(panic_trigger[BLINK], state ? LED_FULL : LED_OFF);
+ led_trigger_event(panic_trigger[ON], LED_FULL);
+ led_trigger_event(panic_trigger[OFF], LED_OFF);
+
return 0;
}

@@ -67,8 +86,12 @@ 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;
+ led_trigger_register_simple("panic", &panic_trigger[BLINK]);
+ led_trigger_register_simple("panic_on", &panic_trigger[ON]);
+ led_trigger_register_simple("panic_off", &panic_trigger[OFF]);
+
+ panic_blink = led_panic_activity;
+
return 0;
}
device_initcall(ledtrig_panic_init);
--
2.17.1