From mboxrd@z Thu Jan 1 00:00:00 1970 From: grant.likely@secretlab.ca (Grant Likely) Date: Tue, 05 Feb 2013 12:45:35 +0000 Subject: [PATCH V2] mxs: spi: clear XFER_COUNT in ctrl0 field in DMA descriptor In-Reply-To: <1356500931-31861-1-git-send-email-juha.lumme@gmail.com> References: <1356500931-31861-1-git-send-email-juha.lumme@gmail.com> Message-ID: <20130205124535.D59043E0E27@localhost> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Wed, 26 Dec 2012 14:48:51 +0900, Juha Lumme wrote: > 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 Applied, thanks. g.