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Subject: Re: Few problems in mtd system
From: Maxim Levitsky <maximlevitsky@gmail.com>
To: =?ISO-8859-1?Q?J=F6rn?= Engel <joern@logfs.org>
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Date: Tue, 22 Dec 2009 20:03:54 +0200
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On Mon, 2009-12-21 at 15:00 +0100, Jörn Engel wrote: 
> On Sun, 20 December 2009 22:59:55 +0200, Maxim Levitsky wrote:
> > 
> > I suspect that older non type M cards didn't have such emulation, but
> > were real nand chips, bacause there are some references on the web about
> > using XD card as a nand chip replacement.
> > Such card as I have will really will make very poor nand replacement...
> 
> If you want to know whether the cards or the readers are to blame, you
> can try to buy an old alauda reader on ebay.  It is too slow to be
> useful for most purposes, but I believe it did give me full access with
> my cards.
> 
> > Folks, could you review my other questions about bugs in mtd core, and
> > tell your opinion?

I have several problems, more correctly bugs in mtd system I have to fix
to make my driver work.

Lets start from  the problem I face now.

Problem is that add_mtd_blktrans_dev is called with mtd_table_mutex
locked, but it calls add_disk which opens the block device if you
specify that you need partitions on the disk. Open routine 'looks' at
mtd table using get_mtd_device, and thus deadlocks.

Do you have a clue how to fix that so it won't break anything?


Best regards,
Maxim Levitsky