gpio: grgpio: Add device driver for GRGPIO cores

This driver supports GRGPIO gpio cores available in the GRLIB VHDL IP
core library from Aeroflex Gaisler.

Signed-off-by: Andreas Larsson <andreas@gaisler.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

1 files changed, 21 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/gpio/gpio-grgpio.txt b/Documentation/devicetree/bindings/gpio/gpio-grgpio.txt
new file mode 100644
index 000000000000..1ec46fdf11d0
--- /dev/null
+++ b/Documentation/devicetree/bindings/gpio/gpio-grgpio.txt
@@ -0,0 +1,21 @@
+Aeroflex Gaisler GRGPIO General Purpose I/O cores.
+
+The GRGPIO GPIO core is available in the GRLIB VHDL IP core library.
+
+Note: In the ordinary environment for the GRGPIO core, a Leon SPARC system,
+these properties are built from information in the AMBA plug&play.
+
+Required properties:
+
+- name : Should be "GAISLER_GPIO" or "01_01a"
+
+- reg : Address and length of the register set for the device
+
+- interrupts : Interrupt numbers for this device
+
+Optional properties:
+
+- nbits : The number of gpio lines. If not present driver assumes 32 lines.
+
+For further information look in the documentation for the GLIB IP core library:
+http://www.gaisler.com/products/grlib/grip.pdf