From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marek Vasut Subject: Re: [PATCH V2] mxs: spi: clear XFER_COUNT in ctrl0 field in DMA descriptor Date: Mon, 7 Jan 2013 13:13:04 +0100 Message-ID: <201301071313.04309.marex@denx.de> References: <1356500931-31861-1-git-send-email-juha.lumme@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: Fabio Estevam , spi-devel-general-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org, Shawn Guo , linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org To: Juha Lumme Return-path: In-Reply-To: <1356500931-31861-1-git-send-email-juha.lumme-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: spi-devel-general-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Id: linux-spi.vger.kernel.org Dear Juha Lumme, > On MX23 the XFER_COUNT part in ctrl0 field in DMA descriptor was improperly > OR'd during the construction of DMA descriptor chain, instead of being > freshly set. > Because of that too many bytes were being expected from SPI during the last > DMA cycle. > This caused a timeout (SSP_TIMEOUT) to happen in the processing of the last > DMA descriptor, and thus reads and writes were failing. > This is a fix for the problem, by clearing XFER_COUNT bytes in ctrl0 before > setting the new XFER_COUNT for DMA descriptor. > > Cc: Marek Vasut > Cc: Fabio Estevam > Cc: Shawn Guo > > Signed-off-by: Juha Lumme > Acked-by: Marek Vasut Bump? This is stable matter too. Best regards, Marek Vasut ------------------------------------------------------------------------------ Master Visual Studio, SharePoint, SQL, ASP.NET, C# 2012, HTML5, CSS, MVC, Windows 8 Apps, JavaScript and much more. Keep your skills current with LearnDevNow - 3,200 step-by-step video tutorials by Microsoft MVPs and experts. SALE $99.99 this month only -- learn more at: http://p.sf.net/sfu/learnmore_122412