From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Wed, 20 May 2015 16:54:47 -0700 From: Brian Norris To: Marek Vasut Subject: Re: [PATCH 0/3] Using SPI NOR flah on sunxi. Message-ID: <20150520235447.GZ11598@ld-irv-0074> References: <201504302034.36753.marex@denx.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <201504302034.36753.marex@denx.de> Cc: Mark Rutland , linux-sunxi , linux-mtd@lists.infradead.org, Alison Chaiken , "Bean Huo ????????? \(beanhuo\)" , linux-mtd , Michal Suchanek , Rafa?? Mi??ecki , Ben Hutchings , devicetree , Pawel Moll , Ian Campbell , Mark Brown , Thomas.Betker@rohde-schwarz.com, Mika Westerberg , "grmoore@altera.com" , Linux Kernel Mailing List , linux-spi@vger.kernel.org, Huang Shijie , Rob Herring , Kumar Gala , David Woodhouse List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Thu, Apr 30, 2015 at 08:34:36PM +0200, Marek Vasut wrote: > On Thursday, April 30, 2015 at 06:56:18 PM, Michal Suchanek wrote: > > On 30 April 2015 at 18:30, wrote: > > > Hello Michal: > > >> I tried to connect a SPI NOR flash to my sunxi board and due to the > > > > > > current > > > > > >> sunxi SPI driver limitations it does not work. > > >> > > >> The SPI driver returns an error when more than 64 bytes are > > >> transferred at once > > >> due to lack of DMA support. > > > > > > Wouldn't it be easier to fix the SPI driver to handle transfers larger > > > than 64 bytes, filling and draining the FIFO multiple times if > > > neccessary? (As far as I can tell, most SPI drivers do this.) > > > > Yes, the intent is to fix this by adding dma support to the driver, > > eventually. > > > > The patch might be still useful for other hardware with developing SPI > > support. > > Please just fix the controller driver to correctly handle arbitrary transfer > lengths. Just noticed this. Yes, that would definitely be a better option! Brian