From mboxrd@z Thu Jan  1 00:00:00 1970
Date: Tue, 29 Jul 2008 10:50:29 +0100 (BST)
From: Alexey Korolev <akorolev@infradead.org>
To: Artem Bityutskiy <dedekind@infradead.org>
Subject: Re: 2nd problem with read_subpage() ?
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Hi Artem,

> On Tue, 2008-07-29 at 12:30 +0300, Artem Bityutskiy wrote:
> > On Tue, 2008-07-29 at 09:53 +0300, Artem Bityutskiy wrote:
> > > Glance at nand_do_read_ops():
> > > 
> > > 
> > > if (likely(sndcmd)) {
> > >         chip->cmdfunc(mtd, NAND_CMD_READ0, 0x00, page);
> > >         sndcmd = 0;
> > > }
> > 
> > Alexey,
> > 
> > my investigation showed that this "random output" command is not
> > supported by all flashes. ST-micro NANDs seems to support it
> > (I checked 2 manuals), while Sumsung NANDs do not (checked manual
> > for K9XXG08UXA). This means your implementation will break many
> > systems and should be either fixed or reverted.
> 
> Note, the Samsung NAND I referred is a large page device.
> 
AFAIK this is a standard feature for LP NANDS. I glanced at spec for
K9XXG08UXA - device supports subpage oprations.

To check it I did this. 
Google -> K9XXG08UXA -> the first link -> open PDF page 41. 

Thanks,
Alexey