Re: [RFC 1/2] dt-bindings: iio: imu: Add DT binding doc for BMI323

From: Jonathan Cameron
Date: Fri Oct 13 2023 - 04:16:22 EST


On Tue, 10 Oct 2023 21:51:17 +0200
Linus Walleij <linus.walleij@xxxxxxxxxx> wrote:

> On Tue, Oct 10, 2023 at 4:42 PM Jonathan Cameron <jic23@xxxxxxxxxx> wrote:
>
> > We kind of lost the question along the way. Wasn't so much about whether
> > there was a generic binding but more about whether it is worth providing
> > separate controls for the two IRQ pins? Or just assume no one is crazy
> > enough to play that level of mix and match.
>
> Ugh no, that's upfront design for a nonexistent use case.
>
> - First, to even consider open drain the designer need to be really
> short of IRQ lines/rails, and, despite knowing it's a bad idea, decide
> to share this line between several peripherals, even though it will
> require I2C traffic to just determine which one even fired the IRQ.
>
> - Second, be interested in using two IRQs to distinguish between
> different events? When we just faced the situation that we had
> too few IRQ lines so we need to start sharing them with open
> drain...?
>
> It's not gonna happen.
>
> Stay with just drive-open-drain; and configure them all as that if
> that property is set.

Good insights, I'd not really thought about the wider reasons for using
this :) Not done any circuit design or embedded board bring up in a
long while.

Thanks!

>
> Yours,
> Linus Walleij
>