gpio: add GPIO driver for the Timberdale FPGA

A GPIO driver for the Timberdale FPGA found on the Intel Atom board
Russellville.

The GPIO driver also has an IRQ-chip to support interrupts on the pins.

Signed-off-by: Richard Röjfors <richard.rojfors@mocean-labs.com>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index 57ca339..a019b49 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -206,6 +206,12 @@
 	help
 	  Say Y here to support Intel Moorestown platform GPIO.
 
+config GPIO_TIMBERDALE
+	bool "Support for timberdale GPIO IP"
+	depends on MFD_TIMBERDALE && GPIOLIB && HAS_IOMEM
+	---help---
+	Add support for the GPIO IP in the timberdale FPGA.
+
 comment "SPI GPIO expanders:"
 
 config GPIO_MAX7301