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Sender: Guenter Roeck <groeck7@gmail.com>
Date:   Tue, 10 Oct 2023 06:45:15 -0700
From:   Guenter Roeck <linux@roeck-us.net>
To:     Wolfram Sang <wsa@kernel.org>,
        Lakshmi Yadlapati <lakshmiy@us.ibm.com>,
        sumit.semwal@linaro.org, christian.koenig@amd.com,
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        dri-devel@lists.freedesktop.org
Subject: Re: [PATCH v1 0/2] [PATCH] hwmon: (pmbus/max31785) Add minimum delay
 between bus accesses
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 <ZSUaDIfWmEn5edrE@shikoro>
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On Tue, Oct 10, 2023 at 11:31:56AM +0200, Wolfram Sang wrote:
> Hi,
> 
> thanks for this series!
> 
> > Reference to Andrew's previous proposal:
> > https://lore.kernel.org/all/20200914122811.3295678-1-andrew@aj.id.au/
> 
> I do totally agree with Guenter's comment[1], though. This just affects
> a few drivers and this patch is way too intrusive for the I2C core. The
> later suggested prepare_device() callback[2] sounds better to me. I
> still haven't fully understood why this all cannot be handled in the
> driver's probe. Could someone give me a small summary about that?
> 

Lots of PMBus devices have the same problem, we have always handled
it in PMBus drivers by implementing local wait code, and your references
point that out. What other summary are you looking for ?

On a side note, if anyone plans to implement the prepare_device() callback,
please make sure that it covers all requirements. It would be unfortunate
if such a callback was implemented if that would still require per-driver
code (besides the callback).

Thanks,
Guenter