RE: [PATCH 1/7] spi: add slave device size in spi_device struct

From: Yogesh Narayan Gaur
Date: Mon Sep 03 2018 - 00:47:34 EST


Hi Lothar,

> -----Original Message-----
> From: Lothar WaÃmann [mailto:LW@xxxxxxxxxxxxxxxxxxx]
> Sent: Friday, August 31, 2018 5:28 PM
> To: Yogesh Narayan Gaur <yogeshnarayan.gaur@xxxxxxx>
> Cc: linux-mtd@xxxxxxxxxxxxxxxxxxx; boris.brezillon@xxxxxxxxxxx;
> marek.vasut@xxxxxxxxx; linux-spi@xxxxxxxxxxxxxxx;
> devicetree@xxxxxxxxxxxxxxx; mark.rutland@xxxxxxx; robh@xxxxxxxxxx; linux-
> kernel@xxxxxxxxxxxxxxx; frieder.schrempf@xxxxxxxxx;
> computersforpeace@xxxxxxxxx; shawnguo@xxxxxxxxxx; linux-arm-
> kernel@xxxxxxxxxxxxxxxxxxx
> Subject: Re: [PATCH 1/7] spi: add slave device size in spi_device struct
>
> Hi,
>
> On Fri, 31 Aug 2018 15:59:58 +0530 Yogesh Gaur wrote:
> > Add 'size' data variable in spi_device struct.
> > This is to save the size of the connected slave device.
> >
> > After slave device scan, spi_nor_scan, size being assigned to this
> > from MTD layer.
> >
> > SFDP read is being requested before completion of spi_nor_scan()
> > routine, thus populate device size before making read request to the
> > SPI controller.
> >
> > Signed-off-by: Yogesh Gaur <yogeshnarayan.gaur@xxxxxxx>
> > ---
> > drivers/mtd/devices/m25p80.c | 6 ++++++
> > drivers/mtd/spi-nor/spi-nor.c | 2 ++
> > include/linux/spi/spi.h | 2 ++
> > 3 files changed, 10 insertions(+)
> >
> > diff --git a/drivers/mtd/devices/m25p80.c
> > b/drivers/mtd/devices/m25p80.c index fe260cc..6c7ad86 100644
> > --- a/drivers/mtd/devices/m25p80.c
> > +++ b/drivers/mtd/devices/m25p80.c
> > @@ -124,6 +124,10 @@ static ssize_t m25p80_read(struct spi_nor *nor,
> loff_t from, size_t len,
> > /* convert the dummy cycles to the number of bytes */
> > op.dummy.nbytes = (nor->read_dummy * op.dummy.buswidth) / 8;
> >
> > + /* for case of SFDP header read commands, populate spi device size */
> > + if (flash->spimem->spi->size == 0)
> > + flash->spimem->spi->size = nor->mtd.size;
> > +
> If the 'size' is an spimem specific variable it should be added to the spi_mem
> struct rather than the spi_device struct.

Sure, would move 'size' from struct spi_device to the struct spi_mem.

--
Regards
Yogesh Gaur.

>
> Lothar WaÃmann