It wasn't possible to enable some features like memory-to-memory transfers or multi block transfers via DT. It is fixed by these patches. Changes for v6: * Use "supported" as default state for "multi-block" property, to keep old DTBs working. Pointed by Andy Shevchenko. Changes for v5: * Update existing DTS. Pointed by Andy Shevchenko. * Read multi-block per chanel instead of per master (Move DW_DMA_MAX_NR_CHANNELS define from regs.h to dma-dw.h to implement this) Pointed by Andy Shevchenko. Changes for v4: * Fix setting inverted value to "dwc->nollp". My fault - I tested with wrong DTS, so DMAC was configured from autoconfig instead of device tree. Pointed by Andy Shevchenko. * Update "multi-block" diescription in documentation to be more clear. Pointed by Arnd Bergmann. Changes for v3: * Update existing platform data. We don't need to update existing DTS because default logic wasn't change: we don't set "is_nollp" if we read configuration from DT before. And we don't set it now if "multi-block" property doesn't exist in DTS. Changes for v2: * I thought about is_memcpy DT property: all known devices, which use DT for configuration, support memory-to-memory transfers. So we don't need to read it from DT. So enable it by default, if we read configuration from DT. * Use "multi-block" instead of "hw-llp" name to be more clear. * Move adding DT property and adding documentation for this property to one patch. Eugeniy Paltsev (2): DW DMAC: enable memory-to-memory transfers support DW DMAC: add multi-block property to device tree Documentation/devicetree/bindings/dma/snps-dma.txt | 2 ++ arch/arc/boot/dts/abilis_tb10x.dtsi | 1 + arch/arm/boot/dts/spear13xx.dtsi | 2 ++ drivers/dma/dw/core.c | 2 +- drivers/dma/dw/platform.c | 18 +++++++++++++++++- drivers/dma/dw/regs.h | 3 ++- drivers/tty/serial/8250/8250_lpss.c | 2 +- include/linux/platform_data/dma-dw.h | 5 +++-- 8 files changed, 29 insertions(+), 6 deletions(-) -- 2.5.5
