From mboxrd@z Thu Jan 1 00:00:00 1970 From: arnd@arndb.de (Arnd Bergmann) Date: Tue, 20 May 2014 13:51:15 +0200 Subject: [PATCH] s3cmci: port DMA code to dmaengine API In-Reply-To: References: <1400522593-6366-1-git-send-email-anarsoul@gmail.com> <6897537.JWQLgZ3Zsx@wuerfel> Message-ID: <6873175.VdOFbJiHYM@wuerfel> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Tuesday 20 May 2014 14:36:49 Vasily Khoruzhick wrote: > On Tue, May 20, 2014 at 1:39 PM, Arnd Bergmann wrote: > > On Tuesday 20 May 2014 13:22:35 Vasily Khoruzhick wrote: > >> Hi Arnd, > >> > >> On Mon, May 19, 2014 at 10:02 PM, Arnd Bergmann wrote: > >> > For this driver, you don't have to go that far, as long as it's > >> > ensure that the pointer to the filter function is available to > >> > the driver, i.e. you can't have a built-in s3mci driver when the > >> > dmaengine driver is a loadable module. > >> > >> OK, so I guess I need to add explicit dependency on > >> CONFIG_S3C24XX_DMAC for s3cmci driver. > >> > >> Btw, I didn't understand if it's acceptable to pass DMA channel number > >> through DMA resource for non-DT case or not? > > > > It's commonly done on certain SoCs, but I'd prefer to not start doing > > it on those that don't do it today. > > > > At the moment, we do it only on s3c64xx, s5p, davinci, omap1, and pxa > > on ARM, as well as arch/blackfin and one MIPS machine. > > I suppose we have to introduce it on s3c24xx in order to keep > > supporting sound, unless we put the audio dma channels into > > s3c_audio_pdata. > > > > I think that would be a better approach, given that you also need > > to put the filter function pointer for the audio stuff somewhere. > > > > Maybe Mark Brown has a strong preference to how he wants this done > > in the audio drivers, then you can do it the same way for s3cmci. > > Let's just leave channel number hardcoded, how it was before conversion. > It doesn't seem to be a good idea to clean non-DT machine code now, since > it's better to put some effort into converting s3c2410 and s3c244{0,2} to DT. Ok, fair enough. I'm actually more interested in making s3c24xx multiplatform capable than moving it to DT, but we that requires a few other patches as well, and we can fix this one along with those. Arnd