Re: [PATCH v2 1/4] spi: dt-bindings: Introduce spi-mosi-idle-low flag

[Börge Strümpfel]

Am Fr., 12. Mai 2023 um 05:30 Uhr schrieb Mark Brown <broonie@xxxxxxxxxx>:
>
> On Fri, May 12, 2023 at 01:13:14AM +0200, Boerge Struempfel wrote:
> > Some spi controller switch the mosi line to high, whenever they are
> > idle. This may not be desired in all use cases. For example neopixel
> > leds can get confused and flicker due to misinterpreting the idle state.
> > Therefore, we introduce a new spi-mode bit, with which the idle behaviour
> > can be overwritten on a per device basis.
> >
> > Signed-off-by: Boerge Struempfel <bstruempfel@xxxxxxxxxxxxxx>
> > ---
> >  .../devicetree/bindings/spi/spi-peripheral-props.yaml       | 6 ++++++
>
> If this is always required for a given device (which I'd expect to be
> the case) why configure it through DT?  I know we've got some legacy
> stuff like that but not all legacy DT choices were good and no need to
> continue the pattern.

Yes this will always be the case for specific spi-device, spi-controller
combinations. Just to make sure, that I understand your suggestion
correctly: You propose to check from the specific spi-device-driver, if
the spi-controller supports this particular mode-bit, and then set it if
it does and thereby loose the need for the DT entry completely?