From mboxrd@z Thu Jan 1 00:00:00 1970 From: mporter@ti.com (Matt Porter) Date: Tue, 20 Mar 2012 10:02:13 -0400 Subject: [PATCH] of: Add generic device tree DMA helpers In-Reply-To: <4F626180.2010902@ti.com> References: <4F22DEF2.5000807@ti.com> <4F621939.9040906@ti.com> <20120315195753.GA2842@n2100.arm.linux.org.uk> <201203152041.53754.arnd@arndb.de> <4F626180.2010902@ti.com> Message-ID: <20120320140213.GG14084@beef> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Thu, Mar 15, 2012 at 10:39:12PM +0100, Cousson, Benoit wrote: > On 3/15/2012 9:41 PM, Arnd Bergmann wrote: > >The numbers definitely need to become local to each of the controllers, but > >that is the case pretty much automatically using the proposed binding, > >because each dma request identifier starts with the phandle of the > >controller. > > Indeed, and in the case of the OMAP SDMA controller, it can handle > up to 127 DMA request lines numbered from 0 to 126... So a local > number seems to be a good representation... especially for a number. > I'm not sure to understand the issue with this binding. > > And AFAIK, there is the only one general purpose DMA controller in > OMAP so far. The other ones are private to some IPs like MMC or USB, > so they do not need necessarily need any DT representation. AM335x has an EDMA controller instead of SDMA. This is the same EDMA found on mach-davinci/ parts. -Matt