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

Geert Uytterhoeven
2018-08-31T11:41:22Z

Hi Yogesh,

Thanks for your patch!

On Fri, Aug 31, 2018 at 12:33 PM Yogesh Gaur <yogeshnarayan.gaur@nxp.com> wrote:
> Add 'size' data variable in spi_device struct.
> This is to save the size of the connected slave device.

What is the "size" of an SPI slave device?

> After slave device scan, spi_nor_scan, size being assigned to this
> from MTD layer.

Ah, this is MTD specific?

> 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@nxp.com>

> --- a/include/linux/spi/spi.h
> +++ b/include/linux/spi/spi.h
> @@ -127,6 +127,7 @@ void spi_statistics_add_transfer_stats(struct spi_statistics *stats,
> * for driver coldplugging, and in uevents used for hotplugging
> * @cs_gpio: gpio number of the chipselect line (optional, -ENOENT when
> * not using a GPIO line)
> + * @size: size of the connected slave device

Please document what is the meaning of "size".

> *
> * @statistics: statistics for the spi_device
> *
> @@ -168,6 +169,7 @@ struct spi_device {
> void *controller_data;
> char modalias[SPI_NAME_SIZE];
> int cs_gpio; /* chip select gpio */
> + u32 size; /* size of slave device */
>
> /* the statistics */
> struct spi_statistics statistics;

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

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when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds