From mboxrd@z Thu Jan 1 00:00:00 1970 From: Geert Uytterhoeven Date: Mon, 04 Aug 2014 08:05:49 +0000 Subject: Re: [PATCH 4/6] dmaengine: rcar-dmac: Add device tree bindings documentation Message-Id: List-Id: References: <3dc5d31428846326bf122a2a9b402a2a80e97681.1406766014.git.horms+renesas@verge.net.au> In-Reply-To: <3dc5d31428846326bf122a2a9b402a2a80e97681.1406766014.git.horms+renesas@verge.net.au> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Simon Horman Cc: Vinod Koul , dmaengine@vger.kernel.org, Linux-sh list , Magnus Damm , Laurent Pinchart , "devicetree@vger.kernel.org" On Thu, Jul 31, 2014 at 2:34 AM, Simon Horman wrote: > --- /dev/null > +++ b/Documentation/devicetree/bindings/dma/renesas,rcar-dmac.txt > @@ -0,0 +1,98 @@ > +* Renesas R-Car DMA Controller Device Tree bindings > + > +Renesas R-Car Generation 2 SoCs have have multiple multi-channel DMA > +controller instances named DMAC capable of serving multiple clients. Channels > +can be dedicated to specific clients or shared between a large number of > +clients. > + > +DMA clients are connected to the DMAC ports referenced by an 8-bit identifier > +called MID/RID. I think the above sentence can be removed, as it's superseded by the first sentence of the successive paragraph: > + > +Each DMA client is connected to one dedicated port of the DMAC, identified by > +an 8-bit port number called the MID/RID. A DMA controller can thus serve up to > +256 clients in total. When the number of hardware channels is lower than the > +number of clients to be served, channels must be shared between multiple DMA > +clients. The association of DMA clients to DMAC channels is fully dynamic and > +not described in these device tree bindings. Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds