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Date:   Fri, 2 Jul 2021 12:51:27 +0530
From:   Viresh Kumar <viresh.kumar@linaro.org>
To:     Jie Deng <jie.deng@intel.com>
Cc:     Wolfram Sang <wsa@kernel.org>, linux-i2c@vger.kernel.org,
        virtualization@lists.linux-foundation.org,
        linux-kernel@vger.kernel.org, mst@redhat.com, arnd@arndb.de,
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        yu1.wang@intel.com, shuo.a.liu@intel.com, conghui.chen@intel.com,
        stefanha@redhat.com
Subject: Re: [PATCH v11] i2c: virtio: add a virtio i2c frontend driver
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On 02-07-21, 15:15, Jie Deng wrote:
> Then what is the need to design this interface as "return the number of
> messages successfully
> processed, or a negative value on error". Just return success or fail is
> enough.

Right, that isn't clear to me as well. And so I asked Wolfram this yesterday.

I think it is left for the clients handle this, i.e. what they want to do with
it if something fails in between.

> Here, we didn't break the contract with the interface "master_xfer", so if
> there is a problem then
> the contract may be the problem.

So in your case here, either you should return 0 or nr (the number of transfers
requested) and anything else can only be sent if the host reports partial
failures.

Also, since this driver is pretty much independent of everything else, and won't
break anything in the kernel, there is still a good chance of getting it merged
for 5.14-rc1/2.. So it would be better if you resend the next version as soon as
possible :)

-- 
viresh