Re: [PATCH 13/28] dt-bindings: serial: move Marvell compatible string to 8250 binding doc

Lubomir Rintel
2020-03-17T19:09:25Z

On Tue, Mar 17, 2020 at 02:48:05PM +0100, Andrew Lunn wrote:
> On Tue, Mar 17, 2020 at 10:39:07AM +0100, Lubomir Rintel wrote:
> > These ports are compatible with NS8250 and handled by the same driver.
> > Get rid of the extra document that fails to document the properties that
> > are actually supported.
>
> Hi Lubmir
>
> This is needs a bit closer examination. By the PXA maintainers. It
> appears there are two serial drivers, the 8250 and a PXA specific
> driver.

Well, for "mrvl,mmp-uart", there are three: SERIAL_OF_PLATFORM,
SERIAL_8250_PXA and SERIAL_PXA:

drivers/tty/serial/8250/8250_of.c: { .compatible = "mrvl,mmp-uart",
drivers/tty/serial/8250/8250_pxa.c: { .compatible = "mrvl,mmp-uart", },
drivers/tty/serial/pxa.c: { .compatible = "mrvl,mmp-uart", },

For that matter, the hardware is also compatible with intel,xscale-uart
and the mrvl,mmp-uart compatible string is perhaps entirely unnecessary.

I guess the story is somewhat similar for mrvl,pxa-uart; I can not
verify though.

I suppose SERIAL_PXA is not really needed at this point and if support
for mrvl,pxa-uart was added to SERIAL_OF_PLATFORM, then SERIAL_8250_PXA
would only be useful for platforms that don't use DT and the DT bits
could be stripped from it eventually. That is -- if PXA maintainers
agree, of course.

> Andrew

Regards
Lubo