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path: root/drivers/dma/mxs-dma.c
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2011-12-23dma: mxs-dma: Don't use CLKGATE bits in CTRL0 to disable DMA channelsLothar Waßmann
This is how the original Freescale code (unintentionally) worked, because the code path which would have asserted the CLKGATE bit was never actually reached in their code. This fixes the nefarious "DMA timout" bug when multiple DMA channels (e.g. GPMI NAND and MMC) are used at the same time. If a better fix for this problem should be found, the clkgate handling could be reinstated. See http://lists.infradead.org/pipermail/linux-arm-kernel/2011-September/065228.html Also reverse the order of mxs_dma_disable_chan() and mxs_dma_reset_chan() in mxs_dma_control() because mxs_dma_reset_chan() can only work when the DMA channel is enabled. Signed-off-by: Lothar Waßmann <LW@KARO-electronics.de> Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
2011-12-23dma: mxs-dma: make mxs_dma_prep_slave_sg() multi user safeLothar Waßmann
Using a static variable for counting the number of CCWs attached to a DMA channel when appending a new descriptor is not multi user safe. Signed-off-by: Lothar Waßmann <LW@KARO-electronics.de> Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
2011-12-23dma: mxs-dma: Always leave mxs_dma_init() with the clock disabled.Lothar Waßmann
There is no need to have the clock enabled all the time the driver is loaded. It will be enabled anyway in mxs_dma_alloc_chan_resources() when a channel is actually going to be used. Signed-off-by: Lothar Waßmann <LW@KARO-electronics.de> Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
2011-12-23dma: mxs-dma: fix a typo in commentLothar Waßmann
Signed-off-by: Lothar Waßmann <LW@KARO-electronics.de> Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
2011-10-27dmaengine: move drivers to dma_transfer_directionVinod Koul
fixup usage of dma direction by introducing dma_transfer_direction, this patch moves dma/drivers/* to use new enum Cc: Jassi Brar <jaswinder.singh@linaro.org> Cc: Russell King <rmk+kernel@arm.linux.org.uk> Cc: Viresh Kumar <viresh.kumar@st.com> Cc: Linus Walleij <linus.walleij@linaro.org> Cc: Nicolas Ferre <nicolas.ferre@atmel.com> Cc: Mika Westerberg <mika.westerberg@iki.fi> Cc: H Hartley Sweeten <hartleys@visionengravers.com> Cc: Li Yang <leoli@freescale.com> Cc: Zhang Wei <zw@zh-kernel.org> Cc: Sascha Hauer <s.hauer@pengutronix.de> Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de> Cc: Shawn Guo <shawn.guo@freescale.com> Cc: Yong Wang <yong.y.wang@intel.com> Cc: Tomoya MORINAGA <tomoya-linux@dsn.lapis-semi.com> Cc: Boojin Kim <boojin.kim@samsung.com> Cc: Barry Song <Baohua.Song@csr.com> Acked-by: Mika Westerberg <mika.westerberg@iki.fi> Acked-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Viresh Kumar <viresh.kumar@st.com> Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com> Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
2011-08-16mxs-dma: enable CLKGATE before accessing registersLothar Waßmann
After calling mxs_dma_disable_chan() for a channel, that channel becomes unusable because some controller registers can only be written when the clock is enabled via CLKGATE. Signed-off-by: Lothar Waßmann <LW@KARO-electronics.de> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2011-07-26ARM: mxs-dma: reset after disable channelDong Aisheng
We met some channels in abnormal state after disable. Reset it to get a clean state. Signed-off-by: Dong Aisheng <b29396@freescale.com> Cc: Vinod Koul <vinod.koul@intel.com> Cc: Shawn Guo <shawn.guo@linaro.org> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2011-07-26dma: mxs-dma: fix unterminated platform_device_id tableAxel Lin
Signed-off-by: Axel Lin <axel.lin@gmail.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2011-07-14dmaengine: mxs-dma: skip request_irq for NO_IRQShawn Guo
In general, the mxs-dma users get separate irq for each channel, but gpmi is special one which has only one irq shared by all gpmi channels. It causes mxs_dma channel allocation function fail for all other gpmi channels except the first one calling into the function. The patch gets request_irq call skipped for NO_IRQ case, and leaves this gpmi specific quirk to gpmi driver to sort out. It will fix above problem if gpmi driver sets chan_irq as gpmi irq for only one channel and NO_IRQ for all the rest channels. Signed-off-by: Shawn Guo <shawn.guo@linaro.org> Cc: Vinod Koul <vinod.koul@intel.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2011-03-02dmaengine: mxs-dma: add dma support for i.MX23/28Shawn Guo
This patch adds dma support for Freescale MXS-based SoC i.MX23/28, including apbh-dma and apbx-dma. * apbh-dma and apbx-dma are supported in the driver as two mxs-dma instances. * apbh-dma is different between mx23 and mx28, hardware version register is used to differentiate. * mxs-dma supports pio function besides data transfer. The driver uses dma_data_direction DMA_NONE to identify the pio mode, and steals sgl and sg_len to get pio words and numbers from clients. * mxs dmaengine has some very specific features, like sense function and the special NAND support (nand_lock, nand_wait4ready). These are too specific to implemented in generic dmaengine driver. * The driver refers to imx-sdma and only a single descriptor is statically assigned to each channel. Signed-off-by: Shawn Guo <shawn.guo@freescale.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>