From mboxrd@z Thu Jan 1 00:00:00 1970 From: Russell King - ARM Linux Subject: Re: [PATCH 1/5] dmaengine: dw_dmac: move to generic DMA binding Date: Tue, 29 Jan 2013 11:18:50 +0000 Message-ID: <20130129111850.GR23505@n2100.arm.linux.org.uk> References: <1359395857-1235-1-git-send-email-arnd@arndb.de> <1359410300-26113-2-git-send-email-arnd@arndb.de> <1359445171.31148.30.camel@smile> <201301291050.23743.arnd@arndb.de> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <201301291050.23743.arnd-r2nGTMty4D4@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: devicetree-discuss-bounces+gldd-devicetree-discuss=m.gmane.org-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org Sender: "devicetree-discuss" To: Arnd Bergmann Cc: Vinod Koul , Viresh Kumar , devicetree-discuss-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org, spear-devel , Andy Shevchenko , linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org List-Id: devicetree@vger.kernel.org On Tue, Jan 29, 2013 at 10:50:23AM +0000, Arnd Bergmann wrote: > (putting back the Cc list, I assumed you dropped them accidentally) That'll be why I don't have a copy of Andy's email to reply to. > On Tuesday 29 January 2013, Andy Shevchenko wrote: > > On Mon, 2013-01-28 at 21:58 +0000, Arnd Bergmann wrote: > > > - if ((last_dw == dw) && (last_bus_id == param)) > > > + /* both the driver and the device must match */ > > > + if (chan->device->dev->driver != &dw_driver.driver) > > > > Could we somehow pass the &.driver to the generic filter function (via > > *_dma_controller_register() ? ) and do this to each DMA driver? How, and what driver gets passed? > My hope is still that we can avoid using filter functions entirely > when we use xlate() logic, and instead just go through the channels > of the dma engine we know we are looking at. Has anyone yet determined whether any of these new DMA engine slave APIs are usable for implementations which have a separate MUX between the DMA engine and the DMA peripheral?