Debugging options for the DMA engine subsystem

This adds Kconfig options for DEBUG and VERBOSE_DEBUG to the DMA
engine subsystem, I got tired of editing the Makefile manually
each time I want to debug things in here, modelled this on the
debug switches for other subsystems and works like a charm when
working on our DMA engines.
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

drivers/dma/Kconfig

@@ -13,6 +13,22 @@ menuconfig DMADEVICES
 	  DMA Device drivers supported by the configured arch, it may
 	  be empty in some cases.
 
+config DMADEVICES_DEBUG
+        bool "DMA Engine debugging"
+        depends on DMADEVICES != n
+        help
+          This is an option for use by developers; most people should
+          say N here.  This enables DMA engine core and driver debugging.
+
+config DMADEVICES_VDEBUG
+        bool "DMA Engine verbose debugging"
+        depends on DMADEVICES_DEBUG != n
+        help
+          This is an option for use by developers; most people should
+          say N here.  This enables deeper (more verbose) debugging of
+          the DMA engine core and drivers.
+
+
 if DMADEVICES
 
 comment "DMA Devices"

drivers/dma/Makefile

+ifeq ($(CONFIG_DMADEVICES_DEBUG),y)
+	EXTRA_CFLAGS	+= -DDEBUG
+endif
+ifeq ($(CONFIG_DMADEVICES_VDEBUG),y)
+	EXTRA_CFLAGS	+= -DVERBOSE_DEBUG
+endif
+
 obj-$(CONFIG_DMA_ENGINE) += dmaengine.o
 obj-$(CONFIG_NET_DMA) += iovlock.o
 obj-$(CONFIG_DMATEST) += dmatest.o