According to this link, it seems that DMA support can be enabled by setting "dma-names" in dts. Also referring to this thread and checking it, the DMA related driver code is also integrated in spi-imx.c.
I am writing a driver for a SPI SRAM device and am using the 23k256 driver (/drivers/mtd/devices/mchp23k256.c) as reference. It seems to me that the IMX SPI controller driver is already handling the DMA mappings and requests, and there is no extra configuration needed other than calling standard SPI API as illustrated in the 23k256 driver?
