Re: [RFC PATCH 0/8] mtd: rawnand: ams-delta: Use gpio-omap accessors for data I/O

Boris Brezillon
2018-07-20T19:25:21Z

On Fri, 20 Jul 2018 19:55:42 +0200
Janusz Krzysztofik <jmkrzyszt@gmail.com> wrote:

> Hi Boris,
>
> On Thursday, July 19, 2018 8:15:08 AM CEST Boris Brezillon wrote:
> > Hi Janusz,
> >
> > On Thu, 19 Jul 2018 01:57:02 +0200
> > Janusz Krzysztofik <jmkrzyszt@gmail.com> wrote:
> >
> > > Implement the idea suggested by Artem Bityutskiy and Tony Lindgren
> > > described in commit b027274d2e3a ("mtd: ams-delta: fix
> > > request_mem_region() failure").
> >
> > Thanks for doing that. I'll review the patches, but I already have a
> > extra request: can you convert this driver to ->exec_op()? It does not
> > necessarily have to be done in this patchset, but, that'd be great to
> > have one more driver converted to the new interface.
>
> OK, I'll have a look as my free time permits.
>
> > BTW, there seems to be a nand_gpio driver, maybe we should merge
> > ams-delta code into nand_gpio after it's been patched to use the GPIO
> > consumer API.
>
> nand_gpio uses a form of read()/write() on a single bidirectional register for
> data transfer, not GPIO, and it does not make use of NRE / NWE signals. Maybe
> the two drivers could be merged to some extent but not entirely, I think.

Well, yes, right now the nand-gpio driver is assuming the data bus
is not bit-banged, but that's something we can easily add. Anyway, my
remark was more a "nice to have" not a hard requirement.