x86: add generic GPIO support to x86

This patch adds the generic GPIO support to the x86
architecture. We do the same as for MIPS, we let
the machine override the gpio callbacks and provide
defaults one in mach-generic.
Signed-off-by: Florian Fainelli <florian.fainelli@telecomint.eu>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

arch/x86/Kconfig

@@ -72,6 +72,9 @@ config GENERIC_BUG
 config GENERIC_HWEIGHT
 	def_bool y
 
+config GENERIC_GPIO
+	def_bool n
+
 config ARCH_MAY_HAVE_PC_FDC
 	def_bool y
 

include/asm-x86/gpio.h

+#ifndef _ASM_I386_GPIO_H
+#define _ASM_I386_GPIO_H
+
+#include <gpio.h>
+
+#endif /* _ASM_I386_GPIO_H */

include/asm-x86/mach-generic/gpio.h

+#ifndef __ASM_MACH_GENERIC_GPIO_H
+#define __ASM_MACH_GENERIC_GPIO_H
+
+int gpio_request(unsigned gpio, const char *label);
+void gpio_free(unsigned gpio);
+int gpio_direction_input(unsigned gpio);
+int gpio_direction_output(unsigned gpio, int value);
+int gpio_get_value(unsigned gpio);
+void gpio_set_value(unsigned gpio, int value);
+int gpio_to_irq(unsigned gpio);
+int irq_to_gpio(unsigned irq);
+
+#include <asm-generic/gpio.h>           /* cansleep wrappers */
+
+#endif /* __ASM_MACH_GENERIC_GPIO_H */