Re: [PATCH 1/6] serial: 8250: remove AR7 support

From: Andy Shevchenko
Date: Thu Sep 21 2023 - 13:53:16 EST


On Thu, Sep 21, 2023 at 01:21:46PM +0200, Jiri Slaby wrote:
> On 21. 09. 23, 13:16, Andy Shevchenko wrote:
> > On Thu, Sep 21, 2023 at 12:36:05PM +0200, Philippe Mathieu-Daudé wrote:
> > > On 20/9/23 22:10, Wolfram Sang wrote:

...

> > > > -#define PORT_AR7 18 /* Texas Instruments AR7 internal UART */
> > >
> > > I'm a bit surprised definitions are removed from the uAPI, isn't
> > > it expected to be very stable? Shouldn't it be better to keep it
> > > defined but modify the comment, mentioning "obsolete" or "deprecated"?
> >
> > The numbers up to 20 must stay, they are being used somewhere, setserial
> > implementation in busybox (IIRC).
>
> But they define it if we don't:
> #ifndef PORT_AR7
> # define PORT_AR7 18
> #endif

Yep, but the problem is that we may not use that number anyway, because two
different versions of kernel can clash on the same version of tool that will
think about AR7 while it's something different. That's why instead of having
reserved space, better to leave with names assigned.

> > NAK.
> I don't mind either way. But likely we should reserve the field if we go and
> remove it (setserial has a number->string mapping in busybox). Hm, then
> reserving it or keep it? Perhaps keep it is better... So ack the NACK :).

--
With Best Regards,
Andy Shevchenko