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Message-ID: <054c1d8f-fb23-4793-b6d1-5d8814209992@linaro.org>
Date:   Fri, 17 Nov 2023 09:32:17 +0000
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Subject: Re: [PATCH v6 1/2] spi: Replace -ENOTSUPP with -EOPNOTSUPP in op
 checking
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To:     AceLan Kao <acelan.kao@canonical.com>,
        Pratyush Yadav <pratyush@kernel.org>,
        Michael Walle <michael@walle.cc>,
        Miquel Raynal <miquel.raynal@bootlin.com>,
        Richard Weinberger <richard@nod.at>,
        Vignesh Raghavendra <vigneshr@ti.com>,
        Mika Westerberg <mika.westerberg@linux.intel.com>,
        Dhruva Gole <d-gole@ti.com>, linux-mtd@lists.infradead.org,
        Mark Brown <broonie@kernel.org>,
        Kamal Dasu <kamal.dasu@broadcom.com>,
        =?UTF-8?Q?Jonathan_Neusch=C3=A4fer?= <j.neuschaefer@gmx.net>,
        Mario Kicherer <dev@kicherer.org>,
        Chuanhong Guo <gch981213@gmail.com>,
        linux-kernel@vger.kernel.org,
        "linux-spi@vger.kernel.org" <linux-spi@vger.kernel.org>
References: <20231116024338.337304-1-acelan.kao@canonical.com>
From:   Tudor Ambarus <tudor.ambarus@linaro.org>
In-Reply-To: <20231116024338.337304-1-acelan.kao@canonical.com>
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I included linux-spi@vger.kernel.org. Please do the same if you're going
to send a new version.

On 11/16/23 02:43, AceLan Kao wrote:
> --- a/drivers/spi/spi-mem.c
> +++ b/drivers/spi/spi-mem.c
> @@ -323,7 +323,7 @@ int spi_mem_exec_op(struct spi_mem *mem, const struct spi_mem_op *op)
>  		return ret;
>  
>  	if (!spi_mem_internal_supports_op(mem, op))
> -		return -ENOTSUPP;
> +		return -EOPNOTSUPP;

this will break user-space if someone uses the return code of
unsupported operations, but I'm not against taking the risk and changing
the return code, as I doubt it's used. Anyway, if we're taking this
path, please specify the risk in the commit message and why we're taking
this risk.