Re: [PATCH v2 2/4] dt-bindings: pinctrl: qcom,tlmm-common: document i2c pull property

[Linus Walleij]

On Thu, Nov 24, 2022 at 2:24 PM Neil Armstrong
<neil.armstrong@xxxxxxxxxx> wrote:
> On 24/11/2022 14:11, Linus Walleij wrote:
> > On Wed, Nov 23, 2022 at 4:20 PM Abel Vesa <abel.vesa@xxxxxxxxxx> wrote:
> >
> >> From: Neil Armstrong <neil.armstrong@xxxxxxxxxx>
> >>
> >> Document the new i2c_pull property introduced for SM8550 setting
> >> an I2C specific pull mode on I2C able pins.
> >>
> >> Signed-off-by: Neil Armstrong <neil.armstrong@xxxxxxxxxx>
> >> Signed-off-by: Abel Vesa <abel.vesa@xxxxxxxxxx>
> > (...)
> >> +      qcom,i2c-pull:
> >> +        type: boolean
> >> +        description: enable bias pull feature designed for I2C on pin
> >
> > But what is this?
> >
> > I2C buses are usually just plain old bias-high-impedance, high-z
> > or open drain, wire-or or whatever you want to call it.
> >
> > But now there is some special i2c mode, huh?
> >
> > The description is pretty much "it is what it is"... can we have
> > some explanation about what this means electrically speaking
> > and why you cannot use bias-high-impedance?
>
> I'll try to get some more info, but so far I only found what I wrote in the bindings.

Björn: can you see if you can get some clarity about the i2c
bias thing?

Yours,
Linus Walleij