From mboxrd@z Thu Jan  1 00:00:00 1970
Subject: 2nd problem with read_subpage() ?
From: Artem Bityutskiy <dedekind@infradead.org>
To: Alexey Korolev <akorolev@infradead.org>
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Date: Tue, 29 Jul 2008 09:53:52 +0300
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Glance at nand_do_read_ops():


if (likely(sndcmd)) {
        chip->cmdfunc(mtd, NAND_CMD_READ0, 0x00, page);
        sndcmd =3D 0;
}

/* Now read the page into the buffer */
if (unlikely(ops->mode =3D=3D MTD_OOB_RAW))
        ret =3D chip->ecc.read_page_raw(mtd, chip, bufpoi);
else if (!aligned && NAND_SUBPAGE_READ(chip) && !oob)
        ret =3D chip->ecc.read_subpage(mtd, chip, col, bytes, bufpoi);
else
        ret =3D chip->ecc.read_page(mtd, chip, bufpoi);
if (ret < 0)
        break;


What happens is that first NAND_CMD_READ0 command is sent, and the
chip reads _full_ page 0. Then read_subpage() is called and chip
reads the subpage again. Does it make any sense?

--=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)