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Date:   Thu, 16 Nov 2023 16:37:44 +0100
From:   Michael Walle <michael@walle.cc>
To:     Mark Brown <broonie@kernel.org>
Cc:     AceLan Kao <acelan.kao@canonical.com>,
        Tudor Ambarus <tudor.ambarus@linaro.org>,
        Pratyush Yadav <pratyush@kernel.org>,
        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,
        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
Subject: Re: [PATCH v6 1/2] spi: Replace -ENOTSUPP with -EOPNOTSUPP in op
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>> The purpose of this patch is to distinguish the "operation not 
>> support"
>> error from the generic "not support", so that drivers could better
>> handle different errors.
> 
> What is the intended distinction between the two?

The commit message is misleading. The intention is to replace
ENOTSUPP with EOPNOTUPP for two reasons:
  (1) checkpatch will complain about the use of ENOTSUPP and apparently
      should only be used with NFS
  (2) more importantly, spi-nor already uses EOPNOTSUPP, but calls to
      spi-mem might return ENOTSUPP. We'd like to unify this.

-michael