Re: [PATCH v3 1/3] dt-bindings: adc-joystick: add adc-joystick,no-hardware-trigger

Chris Morgan
2022-06-15T18:09:41Z

On Wed, Jun 15, 2022 at 10:23:55AM -0700, Krzysztof Kozlowski wrote:
> On 14/06/2022 18:50, Artur Rojek wrote:
> > On 2022-06-13 21:23, Chris Morgan wrote:
> >> From: Chris Morgan <macromorgan@hotmail.com>
> >>
> >> Add documentation for adc-joystick,no-hardware-trigger. New device-tree
> >> properties have been added.
> >>
> >> - adc-joystick,no-hardware-trigger: A boolean value noting the joystick
> >> device should be polled rather than
> >> use a triggered buffer.
> >>
> >> Signed-off-by: Maya Matuszczyk <maccraft123mc@gmail.com>
> >> Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
> >> ---
> >> .../devicetree/bindings/input/adc-joystick.yaml | 9 ++++++++-
> >> 1 file changed, 8 insertions(+), 1 deletion(-)
> >>
> >> diff --git a/Documentation/devicetree/bindings/input/adc-joystick.yaml
> >> b/Documentation/devicetree/bindings/input/adc-joystick.yaml
> >> index 2ee04e03bc22..627cc6c40191 100644
> >> --- a/Documentation/devicetree/bindings/input/adc-joystick.yaml
> >> +++ b/Documentation/devicetree/bindings/input/adc-joystick.yaml
> >> @@ -12,12 +12,19 @@ maintainers:
> >>
> >> description: >
> >> Bindings for joystick devices connected to ADC controllers
> >> supporting
> >> - the Industrial I/O subsystem.
> >> + the Industrial I/O subsystem. Supports both polled devices where no
> >> + iio trigger is available and non-polled devices which are triggered
> >> + by iio.
> >>
> >> properties:
> >> compatible:
> >> const: adc-joystick
> >>
> >> + adc-joystick,no-hardware-trigger:
> > I'm against using Device Tree for this functionality. See my reply to
> > patch 2/3 for details.
>
> I am surprised to see v3 after that comment...

No, I'm sorry I must have missed this comment or glossed over it when
updating a v3. I've tested checking for INDIO_ALL_BUFFER_MODES and that
doesn't seem to trigger the desired behavior (since I think maybe
something in my kernel config is adding INDIO_BUFFER_TRIGGERED, and I'd
hate for behavior to be dependent on what's in the config versus what's
in the hardware). Would it be sufficient to check for
"(INDIO_BUFFER_HARDWARE | INDIO_BUFFER_SOFTWARE)"?

Thank you.

>
> > But in case we do end up going DT way, I would much prefer going with
> > Rob's suggestion of using the existing `poll-interval` input property.
>
> +1 here as well, if above does not work.
>
>
> Best regards,
> Krzysztof