[PATCH 6/6] arm64: defconfig: Enable Renesas DA9062 defconfig

[Geert Uytterhoeven]

Hi Biju,

On Sun, Dec 10, 2023 at 10:50 AM Biju Das <biju.das.jz at bp.renesas.com> wrote:
> > -----Original Message-----
> > From: Geert Uytterhoeven <geert at linux-m68k.org>
> > Sent: Friday, December 1, 2023 3:42 PM
> > Subject: Re: [PATCH 6/6] arm64: defconfig: Enable Renesas DA9062 defconfig
> >
> > On Fri, Dec 1, 2023 at 4:02 PM Biju Das <biju.das.jz at bp.renesas.com>
> > wrote:
> > > > From: Geert Uytterhoeven <geert at linux-m68k.org> On Fri, Dec 1, 2023
> > > > at 12:09 PM Biju Das <biju.das.jz at bp.renesas.com>
> > > > wrote:
> > > > > Enable the config for the Renesas DA9062 PMIC and RTC, as it is
> > > > > populated on RZ/G2UL SMARC EVK.
> > > > >
> > > > > Signed-off-by: Biju Das <biju.das.jz at bp.renesas.com>
> > > >
> > > > Thanks for your patch!
> > > >
> > > > LGTM, but I would have expected (at least)
> > > >
> > > >     CONFIG_INPUT_DA9063_ONKEY=m
> > > >
> > > > too, cfr. my comments on patch 5/6.
> > >
> > > I have tested this, but I get "da9063-onkey da9062-onkey: error -ENXIO:
> > IRQ ONKEY not found"
> > > So, I won't be able to test onkey events. So plaaning to disable this
> > node.
> >
> > Indeed, currently drivers/input/misc/da9063_onkey.c requires an interrupt
> > to function.  I wonder if it can be made to work using a timer and pure
> > polling...
>
> Yes, that is possible by either adding a debugfs to enable polling for testing.
>
> Or
>
> a device tree property for adding poll delay, so that one can have polling support to test onkey driver.

I would go for the latter, cfr. poll-interval in
Documentation/devicetree/bindings/input/gpio-keys.yaml.

> Basically, on a production system we should avoid polling as it unnecessarily wakeup the system.

Wouldn't polling (by Linux) only happen when the system is already
awake?  I think the DA9063 itself handles the onkey when the system
is asleep.

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert at linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds