gpio: add interrupt handling capability to max732x

Most of the GPIO expanders supported by the max732x driver have interrupt
generation capability by reporting changes on input pins through an INT#
pin.  This patch implements the irq_chip functionnality (edge detection
only).

Signed-off-by: Marc Zyngier <maz@misterjones.org>
Cc: Eric Miao <eric.y.miao@gmail.com>
Cc: Jebediah Huang <jebediah.huang@gmail.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>

1 files changed, 7 insertions, 0 deletions

diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index fee678f74a19..1aa63a2e9af5 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -139,6 +139,13 @@ config GPIO_MAX732X
           Board setup code must specify the model to use, and the start
           number for these GPIOs.
 
+config GPIO_MAX732X_IRQ
+        bool "Interrupt controller support for MAX732x"
+        depends on GPIO_MAX732X=y && GENERIC_HARDIRQS
+        help
+          Say yes here to enable the max732x to be used as an interrupt
+          controller. It requires the driver to be built in the kernel.
+
 config GPIO_PCA953X
         tristate "PCA953x, PCA955x, TCA64xx, and MAX7310 I/O ports"
         depends on I2C