Re: [PATCH 0/2] New NAND chip IDs

[Boris Brezillon <boris.brezillon@free-electrons.com>]

On Tue, 28 Jul 2015 17:19:40 +0200
Boris Brezillon <boris.brezillon@free-electrons.com> wrote:

> Hi Hans,
> 
> Here is a more appropriate answer ;-)
> 
> On Tue, 28 Jul 2015 16:49:58 +0200
> Hans de Goede <hdegoede@redhat.com> wrote:
> 
> > Hi,
> > 
> > On 07/28/2015 04:29 PM, Michal Suchanek wrote:
> > > Hello,
> > >
> > > the NAND chips on Cubietech boards are not known to Linux.
> > >
> > > I used Petros Angelatos' patch from sunxi experimental tree for one chip and
> > > added another chip.
> > >
> > > I hope it's ok to send both patches to avoid merge conflict.
> > 
> > I do not think that these patches are a good idea, this will lead to an
> > ever growing manual maintained list of ids, and that is not maintainable
> > IMHO.
> > 
> > For Samsung chips we only need the ecc strength and size the rest is already
> > detected on the fly, and I've a patch in my personal tree to get the
> > ecc strengt and size from the nand without needing to have an entry per
> > chip:
> > 
> > https://github.com/jwrdegoede/linux-sunxi/commit/53b335d33232753b7aa70298009158baadf5a6bf
> > 
> > This is IMHO a much better solution.
> 
> Yes, indeed, this is a better approach, but AFAIR, not all Samsung
> chips use this layout to expose the ECC strength/size info, and I
> guess this is why this method is not used to retrieve the ECC
> requirements.

At least this was true for Hynix chips (see this thread [1]).

[1]http://comments.gmane.org/gmane.linux.drivers.mtd/50252

-- 
Boris Brezillon, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com