From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mark Brown Subject: Re: [PATCH V3 1/2] of: Add generic device tree DMA helpers Date: Thu, 17 May 2012 14:52:36 +0100 Message-ID: <20120517135236.GA5807@sirena.org.uk> References: <1335820679-28721-1-git-send-email-jon-hunter@ti.com> <4FB3D294.4020505@wwwdotorg.org> <201205161942.20296.arnd@arndb.de> <20120517132223.GB9650@n2100.arm.linux.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20120517132223.GB9650@n2100.arm.linux.org.uk> Sender: linux-omap-owner@vger.kernel.org To: Russell King - ARM Linux Cc: Arnd Bergmann , device-tree , Rob Herring , Jassi Brar , Jon Hunter , linux-omap , linux-arm List-Id: devicetree@vger.kernel.org On Thu, May 17, 2012 at 02:22:23PM +0100, Russell King - ARM Linux wrote: > DMA on the other hand seems to have cases where you can make a choice > between two or more providers of the service. The impression that I'm > getting from this thread is that it's difficult to describe that kind > of relationship in DT - DT is good at describing "A provides X to C" > but not "A _or_ B provides X to C and you can chose either A or B > depending on to satisfy X". A similar thing exists in a lot of clock trees - often the final clock block before an IP block includes a mux which could come from one of a number of sources. From mboxrd@z Thu Jan 1 00:00:00 1970 From: broonie@opensource.wolfsonmicro.com (Mark Brown) Date: Thu, 17 May 2012 14:52:36 +0100 Subject: [PATCH V3 1/2] of: Add generic device tree DMA helpers In-Reply-To: <20120517132223.GB9650@n2100.arm.linux.org.uk> References: <1335820679-28721-1-git-send-email-jon-hunter@ti.com> <4FB3D294.4020505@wwwdotorg.org> <201205161942.20296.arnd@arndb.de> <20120517132223.GB9650@n2100.arm.linux.org.uk> Message-ID: <20120517135236.GA5807@sirena.org.uk> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Thu, May 17, 2012 at 02:22:23PM +0100, Russell King - ARM Linux wrote: > DMA on the other hand seems to have cases where you can make a choice > between two or more providers of the service. The impression that I'm > getting from this thread is that it's difficult to describe that kind > of relationship in DT - DT is good at describing "A provides X to C" > but not "A _or_ B provides X to C and you can chose either A or B > depending on to satisfy X". A similar thing exists in a lot of clock trees - often the final clock block before an IP block includes a mux which could come from one of a number of sources.