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From:   Jim Wylder <jwylder@google.com>
Date:   Fri, 16 Jun 2023 17:39:05 -0500
Message-ID: <CAEP57O9c2Ano4qU5V4EK3ePoBHz+N1xFDo8ULEvidPFnBX+0cw@mail.gmail.com>
Subject: Re: [BUG] _regmap_raw_write() - divide-by-zero
To:     Mark Brown <broonie@kernel.org>
Cc:     Russ Weight <russell.h.weight@intel.com>,
        "Gerlach, Matthew" <matthew.gerlach@linux.intel.com>,
        linux-kernel@vger.kernel.org,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        "Rafael J. Wysocki" <rafael@kernel.org>
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Sorry for causing the grief.

For the description would it be something like "Max transfer size
supported on a write"?
Or does that still not describe it correctly?

Jim

On Fri, Jun 16, 2023 at 5:14=E2=80=AFPM Mark Brown <broonie@kernel.org> wro=
te:
>
> On Fri, Jun 16, 2023 at 02:58:24PM -0700, Russ Weight wrote:
>
> > The origination of the regmap->max_raw_write value is here:
> > https://github.com/torvalds/linux/blob/4973ca29552864a7a047ab8a15611a58=
5827412f/drivers/base/regmap/regmap-spi-avmm.c#L663
> > > .max_raw_write =3D SPI_AVMM_VAL_SIZE * MAX_WRITE_CNT,
>
> > SPI_AVMM_VAL_SIZE is defined as 4, and MAX_WRITE_CNT is defined as 1
>
> This should add in some headroom for the value too.
>
> We should also fix the max_raw_write comments since it's a bit confusing
> between users and buses, though AFAICT nothing outside the core ever
> checks.