Re: [PATCH v2 1/2] gpio: dt-bindings: add parsing of loongson gpio offset

[Yinbo Zhu]

在 2023/8/2 下午3:22, Conor Dooley 写道:
> On Wed, Aug 02, 2023 at 09:38:34AM +0800, Yinbo Zhu wrote:
> > 在 2023/8/1 下午11:54, Conor Dooley 写道:
> > > On Tue, Aug 01, 2023 at 04:34:30PM +0800, Yinbo Zhu wrote:
> > > > 在 2023/8/1 下午3:23, Conor Dooley 写道:
> > > > > On Tue, Aug 01, 2023 at 02:39:49PM +0800, Yinbo Zhu wrote:
> > > > > > 在 2023/7/31 下午11:55, Conor Dooley 写道:
> > > > > > > On Mon, Jul 31, 2023 at 05:10:58PM +0800, Yinbo Zhu wrote:
> > > > > > > > Add parsing GPIO configure, input, output, interrupt register offset
> > > > > > > > address and GPIO control mode support.
> > > > > > >
> > > > > > > This reeks of insufficient use of SoC specific compatibles. Do GPIO
> > > > > > > controllers on the same SoC have different register offsets?
> > > > > >
> > > > > >
> > > > > > Yes,
> > > > > >
> > > > > > > Where are the users for this?
> > > > > >
> > > > > >
> > > > > > For example, ls2k500 contains multiple GPIO chips with different
> > > > > > (configure, input, output, interrupt) offset addresses, but all others
> > > > > > are the same.
> > > > >
> > > > > Right. That's admittedly not what I expected to hear! Can you firstly
> > > > > explain this in the commit message,
> > > >
> > > >
> > > > I will add following explain in the commit message. Do you think it's
> > > > suitable?
> > > >
> > > > Loongson GPIO controllers come in multiple variants that are compatible
> > > > except for certain register offset values.  Add support in yaml file for
> > > > device properties allowing to specify them in DT.
> > >
> > > Sure, that would be helpful.
> > >
> > > > > and secondly add a soc-specific
> > > > > compatible for the ls2k500 and only allow these properties on that SoC?
> > >
> > > > Sorry, I may not have described it clearly before, the ls2k500 was only
> > > > as a example, actually, Loongson GPIO controllers (2k500,2k1000,eg)come
> > > > in multiple variants that are compatible except for certain register
> > > > offset values.  So above all offset device property was used to in all
> > > > loongson gpio controller.
> > >
> > > But it would be good to know why they are different. Do they each
> > > support some different features, or was there some other reason for
> > > making controllers like this?
> >
> >
> > There are no other reasons, just differences in these offset addresses.
>
> Huh. Do you have a link to a devicetree for the ls2k500?


Yes,  there was a link about ls2k500 dts,  but that ls2k500 dts has not
yet added a gpio node.  this gpio node will be added later.

Thanks,
Yinbo