memstick: add support for legacy memorysticks

Based partially on MS standard spec quotes from Alex Dubov.

As any code that works with user data this driver isn't recommended to use
to write cards that contain valuable data.

It tries its best though to avoid data corruption and possible damage to
the card.

Tested on MS DUO 64 MB card on Ricoh R592 card reader.

Signed-off-by: Maxim Levitsky <maximlevitsky@gmail.com>
Cc: Valdis Kletnieks <Valdis.Kletnieks@vt.edu>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Alex Dubov <oakad@yahoo.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

MAINTAINERS

@@ -7749,6 +7749,11 @@ W:	http://tifmxx.berlios.de/
 S:	Maintained
 F:	drivers/memstick/host/tifm_ms.c
 
+SONY MEMORYSTICK STANDARD SUPPORT
+M:	Maxim Levitsky <maximlevitsky@gmail.com>
+S:	Maintained
+F:	drivers/memstick/core/ms_block.*
+
 SOUND
 M:	Jaroslav Kysela <perex@perex.cz>
 M:	Takashi Iwai <tiwai@suse.de>

drivers/memstick/core/Kconfig

@@ -24,3 +24,15 @@ config MSPRO_BLOCK
 	  support. This provides a block device driver, which you can use
 	  to mount the filesystem. Almost everyone wishing MemoryStick
 	  support should say Y or M here.
+
+config MS_BLOCK
+	tristate "MemoryStick Standard device driver"
+	depends on BLOCK
+	help
+	  Say Y here to enable the MemoryStick Standard device driver
+	  support. This provides a block device driver, which you can use
+	  to mount the filesystem.
+	  This driver works with old (bulky) MemoryStick and MemoryStick Duo
+	  but not PRO. Say Y if you have such card.
+	  Driver is new and not yet well tested, thus it can damage your card
+	  (even permanently)

drivers/memstick/core/Makefile

@@ -3,5 +3,5 @@
 #
 
 obj-$(CONFIG_MEMSTICK)		+= memstick.o
-
+obj-$(CONFIG_MS_BLOCK)		+= ms_block.o
 obj-$(CONFIG_MSPRO_BLOCK)	+= mspro_block.o