On 08.09.21 03:45, chaochao2021666 wrote:

Dear Marek


For other types of led could be set at the userspace level. But for the
panic,
maybe it would trigger at kernel space during the kernel boot up.

And currently only blink to indicate the error. we need more kinds of
type to indicate the error.

we have two leds in the panic trigger group, all in the panic only one
behavior-- blink.
we need different panic led behavior, so extend the led behavior. I
think add more types of 
LED behavior could be helpful.

To make it even clearer, there are three issues to solve for us:

One is that we have two LEDs mixing a color, red and green, and the
obviously desired panic color it red, not orange.

The other is that the desired state in an error case is non-blinking,
just on (in line with what our U-Boot will do in case the boot fails).

And as we need that behavior prior to userspace, it should be
configurable via DT. But that does not exclude extending the sysfs
interface as well with the new options.

Jan

BRs
Chao


At 2021-09-07 20:20:18, "Marek Behún" [off-list ref] wrote:

quoted

On Mon,  6 Sep 2021 21:53:18 +0800
chaochao2021666@163.com wrote:

quoted

From: chao zeng <redacted>

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

We don't wont gazillion triggers, each for every possible setting.

Instead extend the existing panic trigger to have another sysfs setting
where you can set this behavior.
 echo panic >trigger
 echo blink >on_panic
So the on_panic file can accept "on", "off" or "blink".

Alternatively a pattern could be set as in the ledtrig-pattern trigger.

Also your patches do not use correct spacing in commit titles:
 leds:triggers:Extend the kernel panic LED trigger
should instead be
 leds: triggers: Extend the kernel panic LED trigger

Marek

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