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From:   "Lad, Prabhakar" <prabhakar.csengg@gmail.com>
Date:   Tue, 8 Dec 2020 10:40:42 +0000
Message-ID: <CA+V-a8tCATgVYkxrzQGWg9GhD=70Hy=O_eESa5mcewt2PpUo7Q@mail.gmail.com>
Subject: Re: [PATCH] mtd: spi-nor: winbond: Add support for w25m512jw
To:     Tudor Ambarus <Tudor.Ambarus@microchip.com>
Cc:     "Lad, Prabhakar" <prabhakar.mahadev-lad.rj@bp.renesas.com>,
        Miquel Raynal <miquel.raynal@bootlin.com>,
        Richard Weinberger <richard@nod.at>,
        Vignesh R <vigneshr@ti.com>, linux-mtd@lists.infradead.org,
        Linux-Renesas <linux-renesas-soc@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Biju Das <biju.das.jz@bp.renesas.com>
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Hi Tudor,

On Mon, Dec 7, 2020 at 5:27 PM <Tudor.Ambarus@microchip.com> wrote:
>
> Hi, Lad,
>
> On 10/16/20 2:55 PM, Lad Prabhakar wrote:
> > EXTERNAL EMAIL: Do not click links or open attachments unless you know =
the content is safe
> >
> > This chip is (nearly) identical to the Winbond w25m512jv which is
> > already supported by Linux. Compared to the w25m512jv, the 'jw'
> > has a different JEDEC ID.
>
> W25M512JW-IQ (2 x 256M-bit) Serial MCP (Multi Chip Package) Flash memory,
> introduces a new =E2=80=9CSoftware Die Select (C2h)=E2=80=9D instruction,=
 which we don't
> support. I guess you can't access the second die with what we have in
> mainline. Or am I wrong? We'll need to add support for multi-die support
> if we want to add new multi-die flashes.
>
My bad, yes only the first die is accessible.  I'll post a patch
dropping this id.

Cheers,
Prabhakar