Re: [RFC PATCH v2 07/12] mtd: rawnand: ams-delta: Set port direction once per transfer

From: Janusz Krzysztofik
Date: Wed Aug 08 2018 - 12:54:40 EST

Hi Boris,

On Tuesday, August 7, 2018 8:57:52 PM CEST Boris Brezillon wrote:
> On Tue, 7 Aug 2018 00:29:13 +0200
> Janusz Krzysztofik <jmkrzyszt@xxxxxxxxx> wrote:
> > In its current shape, the driver sets data port direction before each
> > byte read/write operation, even during multi-byte transfers. Since
> > performance of the driver is completely not acceptable on Amstrad Delta
> > after it has been converted to GPIO bitbang, try to improve things a
> > bit by setting the port direction only on first byte of each transfer.
> ...
> I'd suggest a slightly different approach where the data pins
> direction state is stored in the the priv struct and only changed when
> required. This way you just have to add a test in
> ams_delta_read/write_byte().

Good idea, I'm going to use it, thanks.

Once done, may I also move that one earlier in the series so that it can be
applied while our discussion on GPIO bitmap changes still continues?