Date:   Wed, 5 Jan 2022 10:52:00 +0100
From:   Boris Brezillon <boris.brezillon@collabora.com>
To:     Apurva Nandan <a-nandan@ti.com>
Cc:     Miquel Raynal <miquel.raynal@bootlin.com>,
        Richard Weinberger <richard@nod.at>,
        Vignesh Raghavendra <vigneshr@ti.com>,
        Mark Brown <broonie@kernel.org>,
        Patrice Chotard <patrice.chotard@foss.st.com>,
        Christophe Kerello <christophe.kerello@foss.st.com>,
        Daniel Palmer <daniel@0x0f.com>,
        Alexander Lobakin <alobakin@pm.me>,
        <linux-mtd@lists.infradead.org>, <linux-kernel@vger.kernel.org>,
        <linux-spi@vger.kernel.org>, <p.yadav@ti.com>
Subject: Re: [PATCH v3 09/17] mtd: spinand: Add change_mode() in
 manufacturer_ops
Message-ID: <20220105105200.67037833@collabora.com>
In-Reply-To: <20220101074250.14443-10-a-nandan@ti.com>
References: <20220101074250.14443-1-a-nandan@ti.com>
        <20220101074250.14443-10-a-nandan@ti.com>
Organization: Collabora
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On Sat, 1 Jan 2022 13:12:42 +0530
Apurva Nandan <a-nandan@ti.com> wrote:

> Introduce change_mode() manufacturer_op to let the vendor provide the
> implementation of switching of SPI IO modes.
> 
> The method to switch to different SPI IO mode may vary across
> manufacturers. For example, for Winbond, Octal DTR is enabled by
> writing values to the volatile configuration register. So, let the
> manufacturer's code have their own implementation for switching to
> any given SPI IO mode. Manufacturer's code need to take care, if
> the requested protocol change is allowed/needed and how to apply
> it.
> 
> Signed-off-by: Apurva Nandan <a-nandan@ti.com>
> ---
>  include/linux/mtd/spinand.h | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/include/linux/mtd/spinand.h b/include/linux/mtd/spinand.h
> index 5dae0649f2fb..ad924271a248 100644
> --- a/include/linux/mtd/spinand.h
> +++ b/include/linux/mtd/spinand.h
> @@ -298,6 +298,7 @@ struct spinand_devid {
>  /**
>   * struct manufacurer_ops - SPI NAND manufacturer specific operations
>   * @init: initialize a SPI NAND device
> + * @change_mode: switch the SPI NAND flash to a specific SPI protocol
>   * @cleanup: cleanup a SPI NAND device
>   *
>   * Each SPI NAND manufacturer driver should implement this interface so that
> @@ -305,6 +306,8 @@ struct spinand_devid {
>   */
>  struct spinand_manufacturer_ops {
>  	int (*init)(struct spinand_device *spinand);
> +	int (*change_mode)(struct spinand_device *spinand,
> +			   const enum spinand_protocol protocol);

Protocol or mode? Pick one and stick to it. Given you already use
protocol elsewhere, maybe s/select_mode/select_protocol/.

>  	void (*cleanup)(struct spinand_device *spinand);
>  };
>