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Date:   Thu, 12 Dec 2019 17:33:15 +0100
From:   Wolfram Sang <wsa@the-dreams.de>
To:     Luca Ceresoli <luca@lucaceresoli.net>
Cc:     Daniel Mack <daniel@zonque.org>, linux-kernel@vger.kernel.org,
        linux-gpio@vger.kernel.org, linux-i2c@vger.kernel.org,
        alsa-devel@alsa-project.org, devicetree@vger.kernel.org,
        linux-clk@vger.kernel.org, mturquette@baylibre.com,
        sboyd@kernel.org, robh+dt@kernel.org, broonie@kernel.org,
        lee.jones@linaro.org, lars@metafoo.de, pascal.huerst@gmail.com
Subject: Re: [PATCH 07/10] i2c: Add driver for AD242x bus controller
Message-ID: <20191212163315.GA3932@kunai>
References: <20191209183511.3576038-1-daniel@zonque.org>
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 <64adf5d7-754a-f1da-aa9b-11579c5a2780@lucaceresoli.net>
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Hi Luca,

thanks for the review!

> good, but I think there's a problem in this function. A "normal"
> master_xfer function issues a repeated start between one msg and the
> next one, at least in the typical case where all msgs have the same
> slave address. Your implementation breaks repeated start. At first sight
> we might need more complex code here to coalesce all consecutive msgs
> with the same address into a single i2c_transfer() call.

Note that it is by far the standard case that all messages in a transfer
have the same client address (99,999%?). But technically, this is not a
requirement and the repeated start on the bus is totally independent of
the addresses used. It is just a master wanting to send without being
interrupted by another master.

   Wolfram


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