From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marek Vasut Subject: Re: [PATCH 0/3] Using SPI NOR flah on sunxi. Date: Thu, 30 Apr 2015 20:34:36 +0200 Message-ID: <201504302034.36753.marex@denx.de> References: Reply-To: marex-ynQEQJNshbs@public.gmane.org Mime-Version: 1.0 Content-Type: Text/Plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Post: , List-Help: , List-Archive: , List-Unsubscribe: , To: Michal Suchanek Cc: Thomas.Betker-Bf/A/FSCP0w3s4ca2cGeAgC/G2K4zDHf@public.gmane.org, Alison Chaiken , Huang Shijie , "Bean Huo ????????? (beanhuo)" , Ben Hutchings , Brian Norris , devicetree , David Woodhouse , Kumar Gala , "grmoore-EIB2kfCEclfQT0dZR+AlfA@public.gmane.org" , Ian Campbell , Linux Kernel Mailing List , linux-mtd-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-mtd , linux-sunxi , Mark Rutland , Mika Westerberg , Pawel Moll , Rob Herring , Rafa?? Mi??ecki List-Id: devicetree@vger.kernel.org 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. Best regards, Marek Vasut