Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Date:   Wed, 14 Jul 2021 13:27:05 -0600
From:   Rob Herring <robh@kernel.org>
To:     Amelie Delaunay <amelie.delaunay@foss.st.com>
Cc:     Pierre-Yves Mordret <pierre-yves.mordret@foss.st.com>,
        Dan Williams <dan.j.williams@intel.com>,
        Vinod Koul <vkoul@kernel.org>,
        Rob Herring <robh+dt@kernel.org>, dmaengine@vger.kernel.org,
        Alexandre Torgue <alexandre.torgue@foss.st.com>,
        Maxime Coquelin <mcoquelin.stm32@gmail.com>,
        devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-stm32@st-md-mailman.stormreply.com,
        linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH 1/2] dt-bindings: dma: add alternative REQ/ACK protocol
 selection in stm32-dma
Message-ID: <20210714192705.GA3078178@robh.at.kernel.org>
References: <20210624093959.142265-1-amelie.delaunay@foss.st.com>
 <20210624093959.142265-2-amelie.delaunay@foss.st.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20210624093959.142265-2-amelie.delaunay@foss.st.com>
Precedence: bulk

On Thu, 24 Jun 2021 11:39:58 +0200, Amelie Delaunay wrote:
> Default REQ/ACK protocol consists in maintaining ACK signal up to the
> removal of REQuest and the transfer completion.
> In case of alternative REQ/ACK protocol, ACK de-assertion does not wait the
> removal of the REQuest, but only the transfer completion.
> Due to a possible DMA stream lock when transferring data to/from STM32
> USART/UART, this new bindings allow to select this alternative protocol in
> device tree, especially for STM32 USART/UART nodes.
> 
> Signed-off-by: Amelie Delaunay <amelie.delaunay@foss.st.com>
> ---
>  Documentation/devicetree/bindings/dma/st,stm32-dma.yaml | 7 +++++++
>  1 file changed, 7 insertions(+)
> 

Acked-by: Rob Herring <robh@kernel.org>