Re: [PATCH v7 06/13] pwm: add support for sl28cpld PWM controller

From: Lee Jones
Date: Mon Aug 10 2020 - 03:13:36 EST


On Fri, 07 Aug 2020, Michael Walle wrote:

> Hi Uwe, Hi Lee,
>
> Am 2020-08-06 10:40, schrieb Uwe Kleine-König:
> > On Mon, Aug 03, 2020 at 11:35:52AM +0200, Michael Walle wrote:
> > > diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig
> > > index 7dbcf6973d33..a0d50d70c3b9 100644
> > > --- a/drivers/pwm/Kconfig
> > > +++ b/drivers/pwm/Kconfig
> > > @@ -428,6 +428,16 @@ config PWM_SIFIVE
> > > To compile this driver as a module, choose M here: the module
> > > will be called pwm-sifive.
> > >
> > > +config PWM_SL28CPLD
> > > + tristate "Kontron sl28cpld PWM support"
> > > + select MFD_SIMPLE_MFD_I2C
> >
> > Is it sensible to present this option to everyone? Maybe
> >
> > depends on SOME_SYMBOL_ONLY_TRUE_ON_SL28CPLD || COMPILE_TEST
>
> Because there is now no real MFD driver anymore, there is also
> no symbol for that. The closest would be ARCH_ARM64 but I don't
> think that is a good idea.
>
> Lee, what do you think about adding a symbol to the MFD, which
> selects MFD_SIMPLE_MFD_I2C but doesn't enable any C modules?
>
> I.e.
> config MFD_SL28CPLD
> tristate "Kontron sl28cpld"
> select MFD_SIMPLE_MFD_I2C
> help
> Say yes here to add support for the Kontron sl28cpld board
> management controller.
>
> Then all the other device driver could depend on the MFD_SL28CPLD
> symbol.

You want to add a virtual symbol to prevent having to present a real
one? How is that a reasonable solution?

--
Lee Jones [李琼斯]
Senior Technical Lead - Developer Services
Linaro.org │ Open source software for Arm SoCs
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