[U-Boot] [PATCH 0/2] New abstraction layer for handling MMC and FAT commands

[Marek Vasut]

Dear Wolfgang Denk,

> Dear Lukasz Majewski,
> 
> In message <20120727123832.69195dcd at amdc308.digital.local> you wrote:
> > > Sorry if I don't understand, but what exactly is special with MMC and
> > > FAT here?
> > 
> > Those patches are a follow up of a discussion about DFU support in
> > u-boot.
> > "[PATCH 4/7] dfu: MMC specific routines for DFU operation"
> 
> OK, I see.   Guess I will have to start reading these patches then
> (which I didn't so far).
> 
> > In short - during this discussion it has been suggested, that
> > sprintf() + run_command() call shall be replaced with a "_safe" function
> > call, which decouples "real" e.g. MMC write from parsing user data
> > from prompt.
> 
> ...
> 
> > I need the FAT and MMC for DFU patches, on which I work now. Those
> > patches (actually v2) have already been posted to ML and are under
> > review.
> 
> This makes no sense to me.  MMC is just one of the storagte devices we
> support, and especially with the upcoming support of a clean device
> model it makes no sense to handle it special in any way.

Sure, but that might still be a release or so away. So let's not hinder people 
from doing so, rather let's coordinate. Also, I consider there patches helpful, 
as we can use that abstraction during the DM work.

> The same holds for FAT - it is just one out of a number of file
> systems we support, and it makes no sense to add any code to FAT
> support that makes it incompatible with other file systems.

It's not incompatible, how?

> Any such addition should be implemented in a generic way, that is
> agnostic of the underlying storage device and the file system used on
> top of it.

Should, that's the proper word here. It isn't in most of FSs in uboot though and 
I think this is better than nothing.

> It is OK if you then test with one combination only, but the
> implementation shall be generic.

I still consider it better than nothing -- if we have to pick this up and tear 
it apart during the DM, it's also OK, because we will easily figure out what 
parts to put where. So I'm quite fine with these patches.

> Best regards,
> 
> Wolfgang Denk

Best regards,
Marek Vasut