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Date: Mon, 20 Oct 2025 09:15:05 +0200
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From: Hans Verkuil <hverkuil+cisco@kernel.org>
Subject: Re: i2c-designware: not possible to write to different i2c addresses
 in one transfer?
To: Wolfram Sang <wsa+renesas@sang-engineering.com>,
 Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: linux-i2c@vger.kernel.org, Jarkko Nikula <jarkko.nikula@linux.intel.com>,
 Mika Westerberg <mika.westerberg@linux.intel.com>,
 Jan Dabros <jsd@semihalf.com>, Andi Shyti <andi.shyti@kernel.org>
References: <ee6afdd7-3117-43cd-831f-e0ec5ee46f46@kernel.org>
 <aO-KuJ_T9cXsNpIh@ninjato> <aO-kZUwqcoqnFfTh@smile.fi.intel.com>
 <aPUltv8jbxDJ8DcC@shikoro>
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On 19/10/2025 19:53, Wolfram Sang wrote:
> 
>> May I ask a dumb question? Why do we need such an awkward transaction
>> to begin with?
> 
> Because it is allowed per I2C specs? So people will use it.
> 
> Interestingly, a patch has just now been proposed which I haven't looked
> at but I wanted to let you guys already know:
> 
> [PATCH 2/3] i2c: designware: Enable transfer with different target addresses
> https://lore.kernel.org/r/20251017-i2c-dw-v1-2-7b85b71c7a87@bootlin.com
> 
> Maybe you guys can have a look at it?
> 

I'll give it a spin today.

Regards,

	Hans