From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vinod Koul Date: Mon, 15 Dec 2014 14:54:56 +0000 Subject: Re: [PATCH 2/2 v2] dmaengine: rcar-audmapp: independent from SH_DMAE_BASE v2 Message-Id: <20141215145341.GT16827@intel.com> List-Id: References: <87vblknmw3.wl%kuninori.morimoto.gx@renesas.com> In-Reply-To: <87vblknmw3.wl%kuninori.morimoto.gx@renesas.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-sh@vger.kernel.org On Thu, Dec 11, 2014 at 05:31:05AM +0000, Kuninori Morimoto wrote: > > Hi Vinod > > > > When we set simple settings to DMAC, then, it works automatically as cyclic transfer. > > > The usage of this DMA is very limited, so it is super simple. > > > In addition, this is 2nd DMA which is needed on sound. > > > 1st DMA is controled by rcar-dmac.c > > > 2nd DMA is this > > > almost all settings are set by 1st DMA, 2nd DMA is just relay. > > okay that needs to be called out explicitly. While reading driver it wasn't > > very clear > > So which one is the 1st DMA, how will the client configure these two DMAs? > > 1st DMA is rcar-dma which was created by Laurent. > And it has been sent to you now. > > ${LINUX}/sound/soc/sh/rcar/core.c > is the user of these 2 dmac. > 1st DMAC gets "from mem address", and "to reg address". > 2nd DMAC gets "from reg address", and "to reg address". > DMAC's ID are came from DT. So how is the user expectations, will they configure both the engines? -- ~Vinod