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Date:   Mon, 27 Jun 2022 22:03:20 -0700
From:   Jakub Kicinski <kuba@kernel.org>
To:     Michael Walle <michael@walle.cc>
Cc:     Charles Gorand <charles.gorand@effinnov.com>,
        Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>,
        =?UTF-8?B?Q2zDqW1lbnQ=?= Perrochaud <clement.perrochaud@nxp.com>,
        netdev@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 2/2] NFC: nxp-nci: Don't issue a zero length
 i2c_master_read()
Message-ID: <20220627220320.29ca05ec@kernel.org>
In-Reply-To: <20220626194243.4059870-2-michael@walle.cc>
References: <20220626194243.4059870-1-michael@walle.cc>
        <20220626194243.4059870-2-michael@walle.cc>
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On Sun, 26 Jun 2022 21:42:43 +0200 Michael Walle wrote:
> There are packets which doesn't have a payload. In that case, the second
> i2c_master_read() will have a zero length. But because the NFC
> controller doesn't have any data left, it will NACK the I2C read and
> -ENXIO will be returned. In case there is no payload, just skip the
> second i2c master read.

Whoa, are you using this code or just found the problem thru code
inspection? NFC is notorious for having no known users.