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Date:   Fri, 5 Feb 2021 13:29:42 +0000
From:   Mark Brown <broonie@kernel.org>
To:     Alain Volmat <alain.volmat@foss.st.com>
Cc:     amelie.delaunay@foss.st.com, mcoquelin.stm32@gmail.com,
        alexandre.torgue@foss.st.com, linux-spi@vger.kernel.org,
        linux-stm32@st-md-mailman.stormreply.com,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        fabrice.gasnier@foss.st.com
Subject: Re: [PATCH 1/8] spi: stm32: properly handle 0 byte transfer
Message-ID: <20210205132942.GA4720@sirena.org.uk>
References: <1612523342-10466-1-git-send-email-alain.volmat@foss.st.com>
 <1612523342-10466-2-git-send-email-alain.volmat@foss.st.com>
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On Fri, Feb 05, 2021 at 12:08:55PM +0100, Alain Volmat wrote:
> On 0 byte transfer request, return straight from the
> xfer function after finalizing the transfer.

> +	if (transfer->len == 0) {
> +		spi_finalize_current_transfer(master);
> +		return 0;

The driver only needs to finalize the transfer if it returned a value
greater than 0, returning 0 indicates that the transfer is already done.

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