goldfish: NAND flash driver

Fold together the NAND driver for Goldfish from Arve with cleanups by
Jun Nakajima and a tidy up to 3.7 and checkpatch.

This provides a virtual flash driver for the Goldfish Android Virtual Platform,
and which is normally used as the root file system when testing emulated
devices.

Signed-off-by: Mike A. Chan <mikechan@google.com>
Signed-off-by: Arve Hjønnevåg <arve@android.com>
[Ported to handle x86]
Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Signed-off-by: Xiaohui Xin <xiaohui.xin@intel.com>
Signed-off-by: Jun Nakajima <jun.nakajima@intel.com>
Signed-off-by: Bruce Beare <bruce.j.beare@intel.com>
[Ported to 3.4]
Signed-off-by: Tom Keel <thomas.keel@intel.com>
[Ported to 3.7 and tided for checkpatch etc]
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/goldfish/Kconfig

@@ -4,3 +4,9 @@ config GOLDFISH_AUDIO
 	---help---
 	  Emulated audio channel for the Goldfish Android Virtual Device
 
+config MTD_GOLDFISH_NAND
+	tristate "Goldfish NAND device"
+	depends on GOLDFISH
+	help
+	  Drives the emulated NAND flash device on the Google Goldfish
+	  Android virtual device.

drivers/staging/goldfish/Makefile

@@ -3,3 +3,4 @@
 #
 
 obj-$(CONFIG_GOLDFISH_AUDIO) += goldfish_audio.o
+obj-$(CONFIG_MTD_GOLDFISH_NAND)	+= goldfish_nand.o

drivers/staging/goldfish/README

@@ -1,2 +1,12 @@
+Audio
+-----
 - Move to using the ALSA framework not faking it
 - Fix the wrong user page DMA (moving to ALSA may fix that too)
+
+NAND
+----
+- Switch from spinlock to mutex
+- Remove excess checking of parameters in calls
+- Use dma coherent memory not kmalloc/__pa for the memory (this is just
+  a cleanliness issue not a correctness one)
+