dmaengine: add ep93xx DMA support

The ep93xx DMA controller has 10 independent memory to peripheral (M2P)
channels, and 2 dedicated memory to memory (M2M) channels. M2M channels can
also be used by SPI and IDE to perform DMA transfers to/from their memory
mapped FIFOs.

This driver supports both M2P and M2M channels with DMA_SLAVE, DMA_CYCLIC and
DMA_MEMCPY (M2M only) capabilities.

Signed-off-by: Mika Westerberg <mika.westerberg@iki.fi>
Signed-off-by: Ryan Mallon <rmallon@gmail.com>
Acked-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Acked-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig
index 25cf327..2e3b3d3 100644
--- a/drivers/dma/Kconfig
+++ b/drivers/dma/Kconfig
@@ -237,6 +237,13 @@
 	  Support the MXS DMA engine. This engine including APBH-DMA
 	  and APBX-DMA is integrated into Freescale i.MX23/28 chips.
 
+config EP93XX_DMA
+	bool "Cirrus Logic EP93xx DMA support"
+	depends on ARCH_EP93XX
+	select DMA_ENGINE
+	help
+	  Enable support for the Cirrus Logic EP93xx M2P/M2M DMA controller.
+
 config DMA_ENGINE
 	bool