Hi Biju,
On Tue, 1 Jul 2025 at 13:40, Biju Das <biju.das.jz@xxxxxxxxxxxxxx> wrote:
> > From: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>
> > On Mon, 14 Apr 2025 at 17:38, Biju Das <biju.das.jz@xxxxxxxxxxxxxx> wrote:
> > > RZ/G3E SMARC EVK has 3 user buttons called USER_SW1, USER_SW2 and
> > > USER_SW3. Add a DT node in device tree to instantiate the gpio-keys
> > > driver for these buttons.
> > >
> > > Signed-off-by: Biju Das <biju.das.jz@xxxxxxxxxxxxxx>
> > > --- a/arch/arm64/boot/dts/renesas/renesas-smarc2.dtsi
> > > +++ b/arch/arm64/boot/dts/renesas/renesas-smarc2.dtsi
> > > @@ -12,8 +12,13 @@
> > > * SW_SDIO_M2E:
> > > * 0 - SMARC SDIO signal is connected to uSD1
> > > * 1 - SMARC SDIO signal is connected to M.2 Key E connector
> > > + *
> > > + * GPIO keys are enabled by default. Use PMOD_GPIO macros to disable
> > > + them
> > > + * if needed.
> > > */
> > >
> > > +#include <dt-bindings/input/input.h>
> > > +
> > > / {
> > > model = "Renesas RZ SMARC Carrier-II Board";
> > > compatible = "renesas,smarc2-evk"; @@ -27,6 +32,31 @@ aliases
> > > {
> > > serial3 = &scif0;
> > > mmc1 = &sdhi1;
> > > };
> > > +
> > > + keys: keys {
> > > + compatible = "gpio-keys";
> > > +
> > > + key-1 {
> > > + interrupts-extended = <&pinctrl KEY_1_GPIO
> > > + IRQ_TYPE_EDGE_FALLING>;
> >
> > So you are using them as interrupts. Don't you need to configure pin control for that (function 15 =
> > IRQ14)?
>
> The same pin can be configured as TINT or IRQ15, currently it is configured as TINT IRQ.
> Is it ok?
OK.
> > Alternatively, can't you use them as gpios with interrupt facilities?
>
> interrupts-extended = <&pinctrl KEY_1_GPIO IRQ_TYPE_EDGE_FALLING>;
>
> The TINT IRQ will provide the same right? Am I missing anything here?
When you use interrupts directly, the system will detect only key presses,
and fake (timer-based) key releases.
When you use GPIOs with interrupt-capability, the system can detect both
key presses and releases.
See also commit cab3511ea7a0b1fc ("ARM: dts: marzen: Add slide switches").
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx
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
