[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>

arch/arm/Kconfig

@@ -21,6 +21,10 @@ config ARM
 config SYS_SUPPORTS_APM_EMULATION
 	bool
 
+config GENERIC_GPIO
+	bool
+	default n
+
 config GENERIC_TIME
 	bool
 	default n
@@ -163,6 +167,7 @@ config ARCH_VERSATILE
 
 config ARCH_AT91
 	bool "Atmel AT91"
+	select GENERIC_GPIO
 	help
 	  This enables support for systems based on the Atmel AT91RM9200
 	  and AT91SAM9xxx processors.
@@ -304,6 +309,7 @@ config ARCH_PXA
 	bool "PXA2xx-based"
 	depends on MMU
 	select ARCH_MTD_XIP
+	select GENERIC_GPIO
 	select GENERIC_TIME
 	help
 	  Support for Intel's PXA2XX processor line.
@@ -325,11 +331,13 @@ config ARCH_SA1100
 	select ISA
 	select ARCH_DISCONTIGMEM_ENABLE
 	select ARCH_MTD_XIP
+	select GENERIC_GPIO
 	help
 	  Support for StrongARM 11x0 based boards.
 
 config ARCH_S3C2410
 	bool "Samsung S3C2410, S3C2412, S3C2413, S3C2440, S3C2442, S3C2443"
+	select GENERIC_GPIO
 	help
 	  Samsung S3C2410X CPU based systems, such as the Simtec Electronics
 	  BAST (<http://www.simtec.co.uk/products/EB110ITX/>), the IPAQ 1940 or
@@ -354,6 +362,7 @@ config ARCH_LH7A40X
 
 config ARCH_OMAP
 	bool "TI OMAP"
+	select GENERIC_GPIO
 	help
 	  Support for TI's OMAP platform (OMAP1 and OMAP2).
 

arch/avr32/Kconfig

@@ -22,6 +22,10 @@ config AVR32
 config UID16
 	bool
 
+config GENERIC_GPIO
+	bool
+	default y
+
 config GENERIC_HARDIRQS
 	bool
 	default y

drivers/input/keyboard/Kconfig

@@ -215,14 +215,16 @@ config KEYBOARD_AAED2000
 	  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.