input: Extend matrix-keypad device tree binding

Some matrix keypad drivers can support different numbers of rows and
columns. Add a generic binding for these.

Implementation note:

In order to implement this binding in the kernel, we will need to modify
matrix_keypad_() to look up the number of rows and cols in
the keymap. Perhaps this could be done by passing 0 for these parameters?
Many of the parameters can already be set to NULL. Ick.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

1 files changed, 5 insertions, 8 deletions

diff --git a/Documentation/devicetree/bindings/input/omap-keypad.txt b/Documentation/devicetree/bindings/input/omap-keypad.txt
index f2fa5e10493d..34ed1c60ff95 100644
--- a/Documentation/devicetree/bindings/input/omap-keypad.txt
+++ b/Documentation/devicetree/bindings/input/omap-keypad.txt
@@ -6,19 +6,16 @@ A key can be placed at each intersection of a unique row and a unique column.
 The keypad controller can sense a key-press and key-release and report the
 event using a interrupt to the cpu.
 
+This binding is based on the matrix-keymap binding with the following
+changes:
+
+keypad,num-rows and keypad,num-columns are required.
+
 Required SoC Specific Properties:
 - compatible: should be one of the following
    - "ti,omap4-keypad": For controllers compatible with omap4 keypad
       controller.
 
-Required Board Specific Properties, in addition to those specified by
-the shared matrix-keyboard bindings:
-- keypad,num-rows: Number of row lines connected to the keypad
-  controller.
-
-- keypad,num-columns: Number of column lines connected to the
-  keypad controller.
-
 Optional Properties specific to linux:
 - linux,keypad-no-autorepeat: do no enable autorepeat feature.