From mboxrd@z Thu Jan  1 00:00:00 1970
Subject: Re: 2nd problem with read_subpage() ?
From: Artem Bityutskiy <dedekind@infradead.org>
To: Alexey Korolev <akorolev@infradead.org>
In-Reply-To: <1217314432.3124.9.camel@sauron>
References: <1217314432.3124.9.camel@sauron>
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Date: Tue, 29 Jul 2008 12:30:10 +0300
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On Tue, 2008-07-29 at 09:53 +0300, Artem Bityutskiy wrote:
> Glance at nand_do_read_ops():
>=20
>=20
> if (likely(sndcmd)) {
>         chip->cmdfunc(mtd, NAND_CMD_READ0, 0x00, page);
>         sndcmd =3D 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.

--=20
Best regards,
Artem Bityutskiy (=D0=91=D0=B8=D1=82=D1=8E=D1=86=D0=BA=D0=B8=D0=B9 =D0=90=
=D1=80=D1=82=D1=91=D0=BC)