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

Lee Jones
2020-08-13T08:21:25Z

On Mon, 10 Aug 2020, Michael Walle wrote:

> Am 2020-08-10 09:13, schrieb Lee Jones:
> > 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?
>
> (1) Its a symbol on which all sl28cpld will depend on. Thus they will
> all be hidden if that is not set.
> (2) the drivers itself wouldn't need to depend on MFD_SIMPLE_MFD_I2C,
> which is more correct, because they don't have anything to do with
> i2c.

Yes, okay.

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