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Date:   Fri, 16 Jun 2023 15:51:55 -0700
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Subject: Re: [BUG] _regmap_raw_write() - divide-by-zero
Content-Language: en-US
To:     Mark Brown <broonie@kernel.org>
CC:     Jim Wylder <jwylder@google.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>
References: <02da121f-d6f1-73de-1805-4b331ccbc547@intel.com>
 <648e22d2-d455-4439-a00d-4042077a8571@sirena.org.uk>
From:   Russ Weight <russell.h.weight@intel.com>
In-Reply-To: <648e22d2-d455-4439-a00d-4042077a8571@sirena.org.uk>
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On 6/16/23 15:14, Mark Brown wrote:
> 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/4973ca29552864a7a047ab8a15611a585827412f/drivers/base/regmap/regmap-spi-avmm.c#L663
>>> .max_raw_write = 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.

Thanks for the guidance, Mark. We'll put a patch together to fix up the config.

- Russ

>
> 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.