From 1ec1e82f2510e2bdcb6268ed74aa79e1a7bc9594 Mon Sep 17 00:00:00 2001 From: Sascha Hauer Date: Thu, 30 Sep 2010 13:56:34 +0000 Subject: dmaengine: Add Freescale i.MX SDMA support 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 Reviewed-by: Linus Walleij Signed-off-by: Dan Williams --- arch/arm/mach-imx/include/mach/dma-v1.h | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-) (limited to 'arch/arm/mach-imx') diff --git a/arch/arm/mach-imx/include/mach/dma-v1.h b/arch/arm/mach-imx/include/mach/dma-v1.h index 287431cc13e5..ac6fd713828a 100644 --- a/arch/arm/mach-imx/include/mach/dma-v1.h +++ b/arch/arm/mach-imx/include/mach/dma-v1.h @@ -27,6 +27,8 @@ #define imx_has_dma_v1() (cpu_is_mx1() || cpu_is_mx21() || cpu_is_mx27()) +#include + #define IMX_DMA_CHANNELS 16 #define DMA_MODE_READ 0 @@ -96,12 +98,6 @@ int imx_dma_request(int channel, const char *name); void imx_dma_free(int channel); -enum imx_dma_prio { - DMA_PRIO_HIGH = 0, - DMA_PRIO_MEDIUM = 1, - DMA_PRIO_LOW = 2 -}; - int imx_dma_request_by_prio(const char *name, enum imx_dma_prio prio); #endif /* __MACH_DMA_V1_H__ */ -- cgit v1.2.3