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Sender: Guenter Roeck <groeck7@gmail.com>
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Date:   Fri, 11 Aug 2023 16:05:19 -0700
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Subject: Re: [PATCH v3] hwmon: (aquacomputer_d5next) Add selective 200ms delay
 after sending ctrl report
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To:     Aleksa Savic <savicaleksa83@gmail.com>
Cc:     linux-hwmon@vger.kernel.org, Jack Doan <me@jackdoan.com>,
        Jean Delvare <jdelvare@suse.com>, linux-kernel@vger.kernel.org
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 <e7bcf401-991c-808c-66df-65664940bf22@gmail.com>
From:   Guenter Roeck <linux@roeck-us.net>
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On 8/10/23 11:15, Aleksa Savic wrote:
> On 2023-08-10 06:09:13 GMT+02:00, Guenter Roeck wrote:
>> On Mon, Aug 07, 2023 at 07:20:03PM +0200, Aleksa Savic wrote:
>>> Add a 200ms delay after sending a ctrl report to Quadro,
>>> Octo, D5 Next and Aquaero to give them enough time to
>>> process the request and save the data to memory. Otherwise,
>>> under heavier userspace loads where multiple sysfs entries
>>> are usually set in quick succession, a new ctrl report could
>>> be requested from the device while it's still processing the
>>> previous one and fail with -EPIPE. The delay is only applied
>>> if two ctrl report operations are near each other in time.
>>>
>>> Reported by a user on Github [1] and tested by both of us.
>>>
>>> [1] https://github.com/aleksamagicka/aquacomputer_d5next-hwmon/issues/82
>>>
>>> Fixes: 752b927951ea ("hwmon: (aquacomputer_d5next) Add support for Aquacomputer Octo")
>>> Signed-off-by: Aleksa Savic <savicaleksa83@gmail.com>
>>
>> I would have suggested to use fsleep() to avoid unnecessary
>> sleep times if they are small, bt I guess it doesn't make much
>> of a difference.
> 
> Will keep that in mind.
> 
>>
>> Applied.
> 
> Will this patch perhaps be marked for stable?
> 

It has a Fixes: tag, so it will be applied to affected stable releases
automatically, at least if it applies cleanly. I could have added Cc:
stable@ to make it explicit, but I had pushed it already, and I didn't
want to rebase the branch just for that.

Guenter