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path: root/drivers/dma/imx-sdma.c
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2011-01-05Merge branch 'for-rmk' of git://git.pengutronix.de/git/imx/linux-2.6 into ↵Russell King
devel-stable
2010-12-07dmaengine i.MX SDMA: initialize on module_initSascha Hauer
The firmware framework gets initialized during fs_initcall time, so we are not allowed to call request_firmware earlier. Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2010-12-04dmaengine: imx-sdma: fix bug in buffer descriptor initializationAnatolij Gustschin
Currently while submitting scatterlists with more than one SG entry the DMA buffer address from the first SG entry is inserted into all initialized DMA buffer descriptors. This is due to the typo in the for_each_sg() loop where the scatterlist pointer is used for obtaining the DMA buffer address and _not_ the SG list iterator. As a result all received data will be written only into the first DMA buffer while reading. While writing the data from the first DMA buffer is send to the device multiple times. This caused the filesystem destruction on the MMC card when using DMA in mxcmmc driver. Signed-off-by: Anatolij Gustschin <agust@denx.de> Acked-by: Sascha Hauer <s.hauer@pengutronix.de> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2010-12-03dmaengine i.MX SDMA: Allow to run without firmwareSascha Hauer
The SDMA firmware consists of a ROM part and a RAM part. The ROM part is always present in the SDMA engine and is sufficient for many cases. This patch allows to pass in platform data containing the script addresses in ROM, so loading a firmware is optional now. Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de> Acked-by: Dan Williams <dan.j.williams@intel.com>
2010-10-05dmaengine: Add Freescale i.MX SDMA supportSascha Hauer
This patch adds support for the Freescale i.MX SDMA engine. The SDMA engine is a scatter/gather DMA engine which is implemented as a seperate coprocessor. SDMA needs its own firmware which is requested using the standard request_firmware mechanism. The firmware has different entry points for each peripheral type, so drivers have to pass the peripheral type to the DMA engine which in turn picks the correct firmware entry point from a table contained in the firmware image itself. The original Freescale code also supports support for transfering data to the internal SRAM which needs different entry points to the firmware. Support for this is currently not implemented. Also, support for the ASRC (asymmetric sample rate converter) is skipped. I took a very simple approach to implement dmaengine support. Only a single descriptor is statically assigned to a each channel. This means that transfers can't be queued up but only a single transfer is in progress. This simplifies implementation a lot and is sufficient for the usual device/memory transfers. Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de> Reviewed-by: Linus Walleij <linus.ml.walleij@gmail.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>