Re: drivers/mtd/devices/at91_dataflash26.c

Hans-Jürgen Koch
2007-06-25T06:35:54Z

Am Montag 25 Juni 2007 04:51 schrieb David Brownell:
> On Thursday 10 May 2007, Hans-Jürgen Koch wrote:
> > Am Donnerstag 10 Mai 2007 22:07 schrieb David Brownell:
> > > On Friday 27 April 2007, David Brownell wrote:
> > > > On Friday 27 April 2007, Hans-Jürgen Koch wrote:
> > > >
> > > > > > the m25p80 driver
> > > > > > was pretty close to working with those Atmel devices too ...
> > > > > > most of the commands are identical.
> > > > >
> > > > > Thanks for that hint, I'll have a look at the data sheet.
> > >
> > > Any progress on that? I looked again, and yes most commands
> > > are identical.
>
> Still true. :)

I came to the same conclusion.

>
> For that and a boatload of other SPI flash chips. I'm
> wondering just what that JEDEC standard covers; either
> it's got useful command coverage, or vendors of SPI flash
> noticed that converging command sets is a Good Thing.
>
>
> > > - That driver relies on an AT91-only SPI stack that's not
> > > going upstream, instead of drivers/spi/atmel_spi.c;
> > >
> > > - Driver can't even be selected on kernel.org kernel (!!);
> > >
> > > - The m25p80 driver will need at most minor tweaks to
> > > handle those AT26 (and AT25) series chips;
> > >
> > > So 340ea370c2ce89d1c15fbf785460f2f74314ce58 should be reverted.
>
> Also still true...

I agree.

>
>
> > >
> > > - Dave
> > >
> >
> > Dave,
> > sorry for not responding earlier, I was busy with lots of other
> > stuff. At the moment, I'm working on this again. I had a bit
> > of trouble getting a recent kernel working on my test system,
> > but that seems to be OK now.
> >
> > You'll hear from me soon.
>
> Ping? Have a look at
>
> http://lists.infradead.org/pipermail/linux-mtd/2007-June/018706.html

Great! Didn't notice that one.

>
> which depends on the resent mutex conversion patch in the
> "previous message" link of that patch.
>
> That should highlight more reasons why at91_dataflash should
> be reverted ASAP. I'd expect you would be able to just drop
> that in and have it work ...

Looks like that.

> unless you're seeing that nCS0
> issue built out of at91rm9200 errata, in which case there's
> an experiment I can forward to you. :)

I'll look at that ASAP. I had tons of other work on my desk and last time
I tried, SPI was broken on my device. It would be OK for me if you threw out
that at91_dataflash/at91_dataflash26 stuff now.

Thanks,
Hans