Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

This patch adds functionality to the gpio-lib subsystem to make it
possible to enable the gpio-lib code even if the architecture code didn't
request to get it built in.

The archtitecture code does still need to implement the gpiolib accessor
functions in its asm/gpio.h file.  This patch adds the implementations for
x86 and PPC.

With these changes it is possible to run generic GPIO expansion cards on
every architecture that implements the trivial wrapper functions.  Support
for more architectures can easily be added.

Signed-off-by: Michael Buesch <mb@bu3sch.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: David Brownell <david-b@pacbell.net>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Haavard Skinnemoen <hskinnemoen@atmel.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jean Delvare <khali@linux-fr.org>
Cc: Samuel Ortiz <sameo@openedhand.com>
Cc: Kumar Gala <galak@gate.crashing.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

If gpiolib was selected, asm-generic/gpio.h provides some prototypes
for gpio API and implementation helpers.  With this patch, platform
code can implement its GPIO API using gpiolib without custom gpio.h
file.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

Create fallback gpio.h which only contains prototypes for gpio API.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>