dmaengine: Add Arm DMA-350 driver

Add an initial driver for the Arm Corelink DMA-350 controller, to
support basic mem-to-mem async_tx. The design here leaves room for more
fun things like peripheral support and scatter-gather chaining to come
in future.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/6d7d8efefa935d34977b59a74797ab377528db94.1741780808.git.robin.murphy@arm.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

drivers/dma/Kconfig

@@ -93,6 +93,13 @@ config APPLE_ADMAC
 	help
 	  Enable support for Audio DMA Controller found on Apple Silicon SoCs.
 
+config ARM_DMA350
+	tristate "Arm DMA-350 support"
+	select DMA_ENGINE
+	select DMA_VIRTUAL_CHANNELS
+	help
+	  Enable support for the Arm DMA-350 controller.
+
 config AT_HDMAC
 	tristate "Atmel AHB DMA support"
 	depends on ARCH_AT91

drivers/dma/Makefile

@@ -17,6 +17,7 @@ obj-$(CONFIG_ALTERA_MSGDMA) += altera-msgdma.o
 obj-$(CONFIG_AMBA_PL08X) += amba-pl08x.o
 obj-$(CONFIG_AMCC_PPC440SPE_ADMA) += ppc4xx/
 obj-$(CONFIG_APPLE_ADMAC) += apple-admac.o
+obj-$(CONFIG_ARM_DMA350) += arm-dma350.o
 obj-$(CONFIG_AT_HDMAC) += at_hdmac.o
 obj-$(CONFIG_AT_XDMAC) += at_xdmac.o
 obj-$(CONFIG_AXI_DMAC) += dma-axi-dmac.o