Re: XD/smartmedia - how to implement it right?

From: JÃrn Engel
Date: Sat Nov 21 2009 - 05:52:08 EST


On Sat, 21 November 2009 02:25:44 +0200, Maxim Levitsky wrote:
>
> This thread is meant to continue discussion about XD/smartmedia support
> in linux.
>
> I CC'd few peoples that participated in original discussion.
>
> Alex Dubov attempted to write a driver for jmicron device (I have it
> btw), but this was rejected due to code duplication.
>
> I successfully reverse engineered (in my free time) the XD card reader
> found on my laptop (ricoh based one)
>
> I would like to know how you think to implement the subsystem support
> right.
>
> I would go with mmc subsystem + FTL, but according to original thread,
> there are numerous problems with this approach.
>
> Any advice is appreciated.

A novel approach might be to just send the code as a patch. Last time
around noone seemed to have had a real look.

The "mtd uses blocking calls" argument I can help with. For some other
project I've added non-blocking calls to mtd[1].

Biggest problems I see are a) the userspace interface and b) allowing
both raw flash access through MTD and block device access with an FTL.

[1] http://lists.infradead.org/pipermail/linux-mtd/2009-November/028065.html

JÃrn

--
The wise man seeks everything in himself; the ignorant man tries to get
everything from somebody else.
-- unknown
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/