dma: MIC X100 DMA Driver

This patch implements DMA Engine API for DMA controller on MIC X100
Coprocessors. DMA h/w is shared between host and card s/w.
Channels 0 to 3 are used by host and 4 to 7 are used by card.
Since the DMA device doesn't show up as PCIe device, a virtual bus called mic
bus is created and virtual devices are added on that bus to follow device model.
Allowed dma transfer directions are host to card, card to host and card to card.

Reviewed-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Reviewed-by: Nikhil Rao <nikhil.rao@intel.com>
Reviewed-by: Sudeep Dutt <sudeep.dutt@intel.com>
Signed-off-by: Siva Yerramreddy <yshivakrishna@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig
index 1eca7b9..7c8b8c4 100644
--- a/drivers/dma/Kconfig
+++ b/drivers/dma/Kconfig
@@ -33,6 +33,25 @@
 
 comment "DMA Devices"
 
+config INTEL_MIC_X100_DMA
+	tristate "Intel MIC X100 DMA Driver"
+	depends on 64BIT && X86 && INTEL_MIC_BUS
+	select DMAENGINE
+	default N
+	help
+	  This enables DMA support for the Intel Many Integrated Core
+	  (MIC) family of PCIe form factor coprocessor X100 devices that
+	  run a 64 bit Linux OS. This driver will be used by both MIC
+	  host and card drivers.
+
+	  If you are building host kernel with a MIC device or a card
+	  kernel for a MIC device, then say M (recommended) or Y, else
+	  say N. If unsure say N.
+
+	  More information about the Intel MIC family as well as the Linux
+	  OS and tools for MIC to use with this driver are available from
+	  <http://software.intel.com/en-us/mic-developer>.
+
 config INTEL_MID_DMAC
 	tristate "Intel MID DMA support for Peripheral DMA controllers"
 	depends on PCI && X86