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Date: Tue, 26 Nov 2013 22:59:36 -0800
From: Brian Norris <computersforpeace@gmail.com>
To: Uwe =?iso-8859-1?Q?Kleine-K=F6nig?= <u.kleine-koenig@pengutronix.de>
Subject: Re: [PATCH v2] mtd/nand: don't use {read,write}_buf for 8-bit
 transfers
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Cc: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>,
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+ Pekon, Ezequiel

On Tue, Nov 26, 2013 at 10:03:41PM +0100, Uwe Kleine-König wrote:
> On Wed, Mar 13, 2013 at 11:33:04AM +0200, Artem Bityutskiy wrote:

Resurrecting a really old thread, eh? :) I like it!

> > On Mon, 2013-03-04 at 17:47 +0100, Uwe Kleine-König wrote:
> > > diff --git a/include/linux/mtd/nand.h b/include/linux/mtd/nand.h
> > > index 7ccb3c5..8ee4ed1 100644
> > > --- a/include/linux/mtd/nand.h
> > > +++ b/include/linux/mtd/nand.h
> > > @@ -419,6 +419,8 @@ struct nand_buffers {
> > >   *                     flash device.
> > >   * @read_byte:         [REPLACEABLE] read one byte from the chip
> > >   * @read_word:         [REPLACEABLE] read one word from the chip
> > > + * @write_byte         [REPLACEABLE] write a single byte to the chip on the
> > > + *                     low 8 I/O lines
> > >   * @write_buf:         [REPLACEABLE] write data from the buffer to the chip
> > >   * @read_buf:          [REPLACEABLE] read data from the chip into the buffer
> > >   * @select_chip:       [REPLACEABLE] select chip nr
> > > @@ -503,6 +505,7 @@ struct nand_chip {
> > >  
> > >         uint8_t (*read_byte)(struct mtd_info *mtd);
> > >         u16 (*read_word)(struct mtd_info *mtd);
> > > +       void (*write_byte)(struct mtd_info *mtd, uint8_t byte);
> > >         void (*write_buf)(struct mtd_info *mtd, const uint8_t *buf, int len);
> > >         void (*read_buf)(struct mtd_info *mtd, uint8_t *buf, int len);
> > >         void (*select_chip)(struct mtd_info *mtd, int chip);
> > 
> > I would like to make the interface symmetric for read and write. I do
> > not have any 16 bit flashes, so need to somehow encouredge someone who
> > has one to do this. Namely, I'd like to kill 'read_word()', if possible.
> > What's your take on this?
> I don't have a 16 bit flash, so I have the same excuse as you do :-)

Ezequiel and Pekon have 16-bit devices and can do testing, I think. They
also may be interested in your v3 patch.

Brian