[PATCH 2/5] leds: is31fl319x: Fix shutdown GPIO initial state and remove redundant startup pulse

Jun Yan jerrysteve1101 at gmail.com
Wed May 13 07:44:10 PDT 2026


> On Fri, May 8, 2026 at 5:26=E2=80=AFPM Jun Yan <jerrysteve1101 at gmail.com> w=
> rote:
> 
> > 1. Per IS31FL319x datasheet [1], the hardware shutdown pin (SDB) is
> > active-low.
> 
> So that means that driving the line low will shut down the hardware.

Yes, that is right.

> 
> > -       is31->shutdown_gpio =3D devm_gpiod_get_optional(dev, "shutdown", =
> GPIOD_OUT_HIGH);
> > +       is31->shutdown_gpio =3D devm_gpiod_get_optional(dev, "shutdown", =
> GPIOD_OUT_LOW);
> 
> Add a comment here that this will in fact drive the line high,
> because the GPIO line will be flagged as GPIO_ACTIVE_LOW
> in the provider (such as the device tree).
> 
> At least write this in the commit message, it's a missing piece
> that helps readers understand what is going on.

Okay, I will add the necessary comment in the V2 version.

> 
> Have you checked any existing device trees so you don't
> break something here?

I have modified the problematic device trees and CC'd 
the relevant platform mailing lists as well as the device‑tree mailing list [1].

[1] https://lore.kernel.org/linux-devicetree/20260508152435.21389-1-jerrysteve1101@gmail.com/

> 
> If you're breaking platforms you may need a fixup in
> drivers/gpio/gpiolib-of.c to force the consumer active
> low for legacy device trees.

Thanks for the reminder. I will add the necessary fixup in the V2 version.

> 
> Yours,
> Linus Walleij
> 
> Yours,
> Linus Walleij




More information about the linux-arm-kernel mailing list