dt-bindings: img-ascii-lcd: Document a binding for simple ASCII LCDs

Add documentation for a devicetree binding for the simple ASCII LCD
displays found on development boards such as the MIPS Boston, MIPS Malta
& MIPS SEAD3 from Imagination Technologies.

Signed-off-by: Paul Burton <[email protected]>
Acked-by: Rob Herring <[email protected]>
Cc: Mauro Carvalho Chehab <[email protected]>
Cc: Guenter Roeck <[email protected]>
Cc: David S. Miller <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Cc: Geert Uytterhoeven <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Patchwork: https://patchwork.linux-mips.org/patch/14061/
Signed-off-by: Ralf Baechle <[email protected]>

Author: paulburton

Documentation/devicetree/bindings/auxdisplay/img-ascii-lcd.txt

@@ -0,0 +1,17 @@
+Binding for ASCII LCD displays on Imagination Technologies boards
+
+Required properties:
+- compatible : should be one of:
+    "img,boston-lcd"
+    "mti,malta-lcd"
+    "mti,sead3-lcd"
+
+Required properties for "img,boston-lcd":
+- reg : memory region locating the device registers
+
+Required properties for "mti,malta-lcd" or "mti,sead3-lcd":
+- regmap: phandle of the system controller containing the LCD registers
+- offset: offset in bytes to the LCD registers within the system controller
+
+The layout of the registers & properties of the display are determined
+from the compatible string, making this binding somewhat trivial.

MAINTAINERS

@@ -5964,6 +5964,11 @@ M:	Stanislaw Gruszka <[email protected]>
 S:	Maintained
 F:	drivers/usb/atm/ueagle-atm.c
 
+IMGTEC ASCII LCD DRIVER
+M:	Paul Burton <[email protected]>
+S:	Maintained
+F:	Documentation/devicetree/bindings/auxdisplay/img-ascii-lcd.txt
+
 INA209 HARDWARE MONITOR DRIVER
 M:	Guenter Roeck <[email protected]>
 L:	[email protected]