File-copy from v4.4.100

This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

Please refer to that tree for all history prior to this point.

Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/Documentation/devicetree/bindings/gpio/gpio-grgpio.txt b/Documentation/devicetree/bindings/gpio/gpio-grgpio.txt
new file mode 100644
index 0000000..e466598
--- /dev/null
+++ b/Documentation/devicetree/bindings/gpio/gpio-grgpio.txt
@@ -0,0 +1,26 @@
+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.
+
+- irqmap : An array with an index for each gpio line. An index is either a valid
+	index into the interrupts property array, or 0xffffffff that indicates
+	no irq for that line. Driver provides no interrupt support if not
+	present.
+
+For further information look in the documentation for the GLIB IP core library:
+http://www.gaisler.com/products/grlib/grip.pdf