[PATCH v2 1/5] mtd: spi-nor: notify (Q)SPI controller about protocol change

Marek Vasut marex at denx.de
Wed Jul 22 06:41:46 PDT 2015


On Wednesday, July 22, 2015 at 03:17:06 PM, Cyrille Pitchen wrote:
> Once the Quad SPI mode has been enabled on a Micron flash memory, this
> device expects ALL the following commands to use the SPI 4-4-4 protocol.
> The (Q)SPI controller needs to be notified about the protocol change so it
> can adapt and keep on dialoging with the Micron memory.
> 
> Signed-off-by: Cyrille Pitchen <cyrille.pitchen at atmel.com>
> ---
>  drivers/mtd/spi-nor/spi-nor.c | 17 +++++++++++++++++
>  include/linux/mtd/spi-nor.h   | 13 +++++++++++++
>  2 files changed, 30 insertions(+)
> 
> diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c
> index d78831b4422b..93627d4e6be8 100644
> --- a/drivers/mtd/spi-nor/spi-nor.c
> +++ b/drivers/mtd/spi-nor/spi-nor.c
> @@ -163,6 +163,18 @@ static inline int write_disable(struct spi_nor *nor)
>  	return nor->write_reg(nor, SPINOR_OP_WRDI, NULL, 0, 0);
>  }
> 
> +/*
> + * Notify the (Q)SPI controller about the new protocol to be used.

Hi!

Can you please just reword this a little, so that it is absolutelly clear
even to the less bright of us (like me) that this is a notification coming
from the upper layers (ie. the spi-nor framework) toward the hardware ?

> + */
> +static inline int spi_nor_set_protocol(struct spi_nor *nor,
> +				       enum spi_protocol proto)
> +{
> +	if (nor->set_protocol)
> +		return nor->set_protocol(nor, proto);
> +
> +	return 0;
> +}
> +
>  static inline struct spi_nor *mtd_to_spi_nor(struct mtd_info *mtd)
>  {
>  	return mtd->priv;

[...]

Best regards,
Marek Vasut



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