Re: [PATCH 1/2] dt-bindings: mfd: Add ChromeOS fingerprint binding

From: Stephen Boyd
Date: Tue Mar 15 2022 - 11:50:43 EST


Quoting Alexandru M Stan (2022-03-14 17:23:38)
> On Mon, Mar 14, 2022 at 4:22 PM Stephen Boyd <swboyd@xxxxxxxxxxxx> wrote:
> >
> > + compatible = "google,cros-ec-fp";
> > + reg = <0>;
> > + interrupt-parent = <&gpio_controller>;
> > + interrupts = <4 IRQ_TYPE_LEVEL_LOW>;
> > + spi-max-frequency = <3000000>;
> > + google,cros-ec-spi-msg-delay = <37>;
> > + google,cros-ec-spi-pre-delay = <5>;
> > + reset-gpios = <&gpio_controller 5 GPIO_ACTIVE_LOW>;
> > + boot0-gpios = <&gpio_controller 10 GPIO_ACTIVE_LOW>;
> This should say GPIO_ACTIVE_HIGH, since there's no inverting going on
> either with a real inverter, or the convention (of 'N' being in the
> pin name).
>
> It might be easier to reason about if there's no invesion going for this signal.
>
> Consider it like an enum instead of a verb (unlike active_low
> reset-gpios which can be considered: in reset if it's set):
>
> enum boot0 {
> normal = 0,
> bootloader = 1,
> };

Ok got it! I have in my notes that physically high line means normal
boot mode and physically low is bootloader mode. I confused myself. I'll
fix this.