From mboxrd@z Thu Jan 1 00:00:00 1970 From: broonie@kernel.org (Mark Brown) Date: Fri, 18 Mar 2016 20:33:52 +0000 Subject: [PATCH 1/2] spi: sun4i: add DMA support In-Reply-To: <20160318202310.GS30977@lukather> References: <1456466217-6793-2-git-send-email-plaes@plaes.org> <20160226122504.GR18327@sirena.org.uk> <20160306214206.GW8418@lukather> <20160317072721.GJ30977@lukather> <20160317114308.GF2566@sirena.org.uk> <20160318202310.GS30977@lukather> Message-ID: <20160318203352.GL2566@sirena.org.uk> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Fri, Mar 18, 2016 at 09:23:10PM +0100, Maxime Ripard wrote: > On Thu, Mar 17, 2016 at 12:54:08PM +0100, Michal Suchanek wrote: > > Very few device drivers would work with 63byte transfers only and the > > code for manually driving the CS line in case the DMA engine fails to > > configure will necessarily go untested most of the time since most > > systems will have DMA configured properly. > That's not true. A significant portion would work. I don't like to > make up numbers, but I guess only the EEPROMs and rather big screens > wouldn't work. You'll probably also see devices doing things like firmware downloads, there's a bunch of applications for larger transfers. Like you say it's definitely not going to be a universal problem though, there's many devices that just use SPI for fast register access. -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 473 bytes Desc: not available URL: