dmaengine: mediatek: Add MediaTek Command-Queue DMA controller for MT6765 SoC

MediaTek Command-Queue DMA controller (CQDMA) on MT6765 SoC is dedicated
to memory-to-memory transfer through queue based descriptor management.

There are only 3 physical channels inside CQDMA, while the driver is
extended to support 32 virtual channels for multiple dma users to issue
dma requests onto the CQDMA simultaneously.
Signed-off-by: Shun-Chih Yu <shun-chih.yu@mediatek.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>

drivers/dma/mediatek/Kconfig

@@ -11,3 +11,16 @@ config MTK_HSDMA
 	  This controller provides the channels which is dedicated to
 	  memory-to-memory transfer to offload from CPU through ring-
 	  based descriptor management.
+
+config MTK_CQDMA
+	tristate "MediaTek Command-Queue DMA controller support"
+	depends on ARCH_MEDIATEK || COMPILE_TEST
+	select DMA_ENGINE
+	select DMA_VIRTUAL_CHANNELS
+	select ASYNC_TX_ENABLE_CHANNEL_SWITCH
+	help
+	  Enable support for Command-Queue DMA controller on MediaTek
+	  SoCs.
+
+	  This controller provides the channels which is dedicated to
+	  memory-to-memory transfer to offload from CPU.

drivers/dma/mediatek/Makefile

 obj-$(CONFIG_MTK_HSDMA) += mtk-hsdma.o
+obj-$(CONFIG_MTK_CQDMA) += mtk-cqdma.o