[PATCH] add CONFIG_GENERIC_GPIO

Most drivers using GPIOs already know they are running on a system that
supports the generic GPIO calls, because of other platform dependencies.
But the generic GPIO-based LED and input button drivers can't know that.

So this patch adds a Kconfig hook, GENERIC_GPIO, to mark the platforms
where <asm/gpio.h> will do the right thing.  Currently that's a bunch of
ARMs, and AVR32; more are on the way.

It also fixes a dependency bug for the gpio button input driver; it was
wrong to start with, now it covers all platforms with GENERIC_GPIO.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Acked-by: Richard Purdie <rpurdie@rpsys.net>
Cc: Arnaud Patard <arnaud.patard@rtp-net.org>
Cc: <raph@8d.com>
Cc: <msvoboda@ra.rockwell.com>
Cc: pHilipp Zabel <philipp.zabel@gmail.com>
Cc: Haavard Skinnemoen <hskinnemoen@atmel.com>
Cc: Dmitry Torokhov <dtor@mail.ru>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/input/keyboard/Kconfig b/drivers/input/keyboard/Kconfig
index 6450968..f17e9c7 100644
--- a/drivers/input/keyboard/Kconfig
+++ b/drivers/input/keyboard/Kconfig
@@ -215,14 +215,16 @@
 	  module will be called aaed2000_kbd.
 
 config KEYBOARD_GPIO
-	tristate "Buttons on CPU GPIOs (PXA)"
-	depends on (ARCH_SA1100 || ARCH_PXA || ARCH_S3C2410)
+	tristate "GPIO Buttons"
+	depends on GENERIC_GPIO
 	help
 	  This driver implements support for buttons connected
-	  directly to GPIO pins of SA1100, PXA or S3C24xx CPUs.
+	  to GPIO pins of various CPUs (and some other chips).
 
 	  Say Y here if your device has buttons connected
-	  directly to GPIO pins of the CPU.
+	  directly to such GPIO pins.  Your board-specific
+	  setup logic must also provide a platform device,
+	  with configuration data saying which GPIOs are used.
 
 	  To compile this driver as a module, choose M here: the
 	  module will be called gpio-keys.