RE: [EXT] Re: [1/3] rtc/fsl: support flextimer for lx2160a

[Biwen Li <biwen.li@nxp.com>]

> 
> On 26/08/2019 03:37:43+0000, Biwen Li wrote:
> > >
> > > On Fri, 2019-08-23 at 17:57 +0800, Biwen Li wrote:
> > > > The patch supports flextimer for lx2160a
> > > >
> > > > Signed-off-by: Biwen Li <biwen.li@nxp.com>
> > > > ---
> > > >  drivers/rtc/rtc-fsl-ftm-alarm.c | 1 +
> > > >  1 file changed, 1 insertion(+)
> > > >
> > > > diff --git a/drivers/rtc/rtc-fsl-ftm-alarm.c
> > > > b/drivers/rtc/rtc-fsl- ftm-alarm.c index
> > > > 4f7259c2d6a3..2b81525f6db8 100644
> > > > --- a/drivers/rtc/rtc-fsl-ftm-alarm.c
> > > > +++ b/drivers/rtc/rtc-fsl-ftm-alarm.c
> > > > @@ -313,6 +313,7 @@ static const struct of_device_id
> > > > ftm_rtc_match[] = {
> > > >       { .compatible = "fsl,ls1088a-ftm-alarm", },
> > > >       { .compatible = "fsl,ls208xa-ftm-alarm", },
> > > >       { .compatible = "fsl,ls1028a-ftm-alarm", },
> > > > +     { .compatible = "fsl,lx2160a-ftm-alarm", },
> > > >       { },
> > > >  };
> > > >
> > >
> > > Since there's no data associated with each compatible, it doesn't
> > > seem like there's any need to add a new one.
> > >
> > > What's normally done is add two compatibles in the dts, the base
> > > version and the specific version, e.g.:
> > >
> > > +               rcpm: rcpm@1e34040 {
> > > +                       compatible = "fsl,lx2160a-rcpm",
> > > + "fsl,qoriq-cpm-2.1+";
> > >
> > > Or in this case, compatible = "fsl,lx2160a-ftm-alarm",
> > > "fsl,ls1088a-ftm-alarm";
> > >
> > > Then there's no need to add to the driver list.
> > Yes, it will be work. But it will be confusing. Is ls1088a same with lx2160a? No.
> 
> Well, if you are sure it is the exact same IP that is used, then you should only use
> one compatible. We usually use the name of the first SoC that had the IP. Is it
> confusing anyone? Probably not because this will be in a dtsi that nobody will
> read.
> 
> Note that adding so many compatbile will increase the boot time of your
> platform and this is annoying many NXP customers of the i.mx line.

Yeah, that makes sense.
> 
> --
> Alexandre Belloni, Bootlin
> Embedded Linux and Kernel engineering
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