bcma: gpio: add own IRQ domain

Input GPIO changes can generate interrupts, but we need kind of ACK for
them by changing IRQ polarity. This is required to stop hardware from
keep generating interrupts and generate another one on the next GPIO
state change.
This code allows using GPIOs with standard interrupts and add for
example GPIO buttons support.

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Acked-by: Hauke Mehrtens <hauke@hauke-m.de>
Signed-off-by: John Crispin <blogic@openwrt.org>
Patchwork: http://patchwork.linux-mips.org/patch/6216/
diff --git a/drivers/bcma/Kconfig b/drivers/bcma/Kconfig
index 7c081b3..0ee48be 100644
--- a/drivers/bcma/Kconfig
+++ b/drivers/bcma/Kconfig
@@ -75,6 +75,7 @@
 config BCMA_DRIVER_GPIO
 	bool "BCMA GPIO driver"
 	depends on BCMA && GPIOLIB
+	select IRQ_DOMAIN if BCMA_HOST_SOC
 	help
 	  Driver to provide access to the GPIO pins of the bcma bus.