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From:   Shengjiu Wang <shengjiu.wang@gmail.com>
Date:   Tue, 12 May 2020 10:48:41 +0800
Message-ID: <CAA+D8ANK+Sd=nPeDZpd_=fQRFOdLtKgvsCmfQ_fRU3RCjMY+rQ@mail.gmail.com>
Subject: Re: [PATCH 2/3] ASoC: fsl_esai: Add support for imx8qm
To:     Mark Brown <broonie@kernel.org>
Cc:     Shengjiu Wang <shengjiu.wang@nxp.com>,
        "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" 
        <devicetree@vger.kernel.org>,
        Linux-ALSA <alsa-devel@alsa-project.org>,
        Timur Tabi <timur@kernel.org>, Xiubo Li <Xiubo.Lee@gmail.com>,
        Liam Girdwood <lgirdwood@gmail.com>,
        linuxppc-dev@lists.ozlabs.org, Takashi Iwai <tiwai@suse.com>,
        Nicolin Chen <nicoleotsuka@gmail.com>,
        Rob Herring <robh+dt@kernel.org>,
        Fabio Estevam <festevam@gmail.com>,
        linux-kernel <linux-kernel@vger.kernel.org>
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Hi Mark, Nicolin

On Wed, May 6, 2020 at 10:33 AM Shengjiu Wang <shengjiu.wang@gmail.com> wrote:
>
> Hi
>
> On Fri, May 1, 2020 at 6:23 PM Mark Brown <broonie@kernel.org> wrote:
> >
> > On Fri, May 01, 2020 at 04:12:05PM +0800, Shengjiu Wang wrote:
> > > The difference for esai on imx8qm is that DMA device is EDMA.
> > >
> > > EDMA requires the period size to be multiple of maxburst. Otherwise
> > > the remaining bytes are not transferred and thus noise is produced.
> >
> > If this constraint comes from the DMA controller then normally you'd
> > expect the DMA controller integration to be enforcing this - is there no
> > information in the DMA API that lets us know that this constraint is
> > there?
>
> No, I can't find one API for this.
> Do you have a recommendation?
>
could you please recommend which DMA API can I use?

best regards
wang shengjiu