From: Marek Vasut <marex@denx.de>
To: Cyrille Pitchen <cyrille.pitchen@atmel.com>
Subject: Re: [PATCH v2 1/5] mtd: spi-nor: notify (Q)SPI controller about protocol change
Date: Wed, 22 Jul 2015 15:41:46 +0200
User-Agent: KMail/1.13.7 (Linux/3.14-2-amd64; KDE/4.13.1; x86_64; ; )
Cc: nicolas.ferre@atmel.com, broonie@kernel.org, linux-spi@vger.kernel.org,
        dwmw2@infradead.org, computersforpeace@gmail.com, zajec5@gmail.com,
        beanhuo@micron.com, juhosg@openwrt.org, shijie.huang@intel.com,
        ben@decadent.org.uk, linux-kernel@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org, devicetree@vger.kernel.org,
        robh+dt@kernel.org, pawel.moll@arm.com, mark.rutland@arm.com,
        ijc+devicetree@hellion.org.uk, galak@codeaurora.org,
        linux-mtd@lists.infradead.org
References: <cover.1437569902.git.cyrille.pitchen@atmel.com> <036f143509fed3f303508d1688d68012790f835a.1437569902.git.cyrille.pitchen@atmel.com>
In-Reply-To: <036f143509fed3f303508d1688d68012790f835a.1437569902.git.cyrille.pitchen@atmel.com>
MIME-Version: 1.0
Content-Type: Text/Plain;
  charset="us-ascii"
Content-Transfer-Encoding: 7bit
Message-Id: <201507221541.46135.marex@denx.de>
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 1798
Lines: 52

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@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
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/