Re: [PATCH v1 1/1] mux: consumer: Add dummy functions for !CONFIG_MULTIPLEXER case

[Kuppuswamy, Sathyanarayanan]

Hi Peter,

On 7/8/2017 1:55 PM, Peter Rosin wrote:
> On 2017-07-07 23:41, sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx wrote:
> > From: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx>
> >
> > Add dummy functions to avoid compile time issues when CONFIG_MULTIPLEXER
> > is not enabled.
> Hi!
>
> Consumers should "select MULTIPLEXER",
 If their driver can't work without mux_* calls then  you can make it 
compulsory. But its not always true.
>   so this does not make sense.
> Or do you have a driver that has an optional mux consumer?
I came across this case when I was working on Intel USB MUX driver. I 
think you know the history behind it. Although I am not planning to 
merge that driver now, but I think the use case is still valid.
> > Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx>
> > ---
> >   include/linux/mux/consumer.h | 38 ++++++++++++++++++++++++++++++++++++++
> >   1 file changed, 38 insertions(+)
> >
> > diff --git a/include/linux/mux/consumer.h b/include/linux/mux/consumer.h
> > index 5577e1b..744a5b8 100644
> > --- a/include/linux/mux/consumer.h
> > +++ b/include/linux/mux/consumer.h
> > @@ -16,6 +16,7 @@
> >   struct device;
> >   struct mux_control;
> >   
> > +#ifdef CONFIG_MULTIPLEXER
> >   unsigned int mux_control_states(struct mux_control *mux);
> >   int __must_check mux_control_select(struct mux_control *mux,
> >   				    unsigned int state);
> > @@ -29,4 +30,41 @@ void mux_control_put(struct mux_control *mux);
> >   struct mux_control *devm_mux_control_get(struct device *dev,
> >   					 const char *mux_name);
> >   
> > +#else
> > +unsigned int mux_control_states(struct mux_control *mux)
> static inline
>
> Cheers,
> peda
>
> > +{
> > +	return -ENODEV;
> > +}
> > +
> > +int __must_check mux_control_select(struct mux_control *mux,
> > +				    unsigned int state)
> > +{
> > +	return -ENODEV;
> > +}
> > +
> > +int __must_check mux_control_try_select(struct mux_control *mux,
> > +					unsigned int state)
> > +{
> > +	return -ENODEV;
> > +}
> > +
> > +int mux_control_deselect(struct mux_control *mux)
> > +{
> > +	return -ENODEV;
> > +}
> > +
> > +struct mux_control *mux_control_get(struct device *dev, const char *mux_name)
> > +{
> > +	return ERR_PTR(-ENODEV);
> > +}
> > +
> > +void mux_control_put(struct mux_control *mux) {}
> > +
> > +struct mux_control *devm_mux_control_get(struct device *dev,
> > +					 const char *mux_name)
> > +{
> > +	return ERR_PTR(-ENODEV);
> > +}
> > +#endif
> > +
> >   #endif /* _LINUX_MUX_CONSUMER_H */