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authorSjoerd Simons <sjoerd.simons@collabora.co.uk>2014-11-27 16:34:08 +0100
committerSimon Glass <sjg@chromium.org>2015-01-05 17:45:16 -0700
commit9332274989009b213a405134202088e1bd81fe51 (patch)
tree0f501bf747ffa134f98a774ad463418b93547aa5 /doc/device-tree-bindings
parentee5ee87642fdf57ee0c116b9bb5d65b838f09897 (diff)
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cros-ec-keyboard: Synchronize DT binding from linux
The ChromeOS EC keyboard is used by various different chromebooks. Peach pi being the third board in the u-boot tree to use it (snow and peach pit the other two). Rather then embedding the same big DT node in the peach-pi DT again, copy the dtsi snippit & bindings documentation from linux and include it in all 3 boards. This slightly changes the dt bindings in u-boot: * google,key-rows becomes keypad,num-rows * google,key-colums becomes keypad,num-colums * google,repeat-delay-ms and google,repeat-rate-ms are no longer used and replaced by hardcoded values (similar to tegra kbc) Signed-off-by: Sjoerd Simons <sjoerd.simons@collabora.co.uk> Acked-by: Simon Glass <sjg@chromium.org> Tested-by: Simon Glass <sjg@chromium.org>
Diffstat (limited to 'doc/device-tree-bindings')
-rw-r--r--doc/device-tree-bindings/input/cros-ec-keyb.txt53
1 files changed, 23 insertions, 30 deletions
diff --git a/doc/device-tree-bindings/input/cros-ec-keyb.txt b/doc/device-tree-bindings/input/cros-ec-keyb.txt
index 3118276..0f6355c 100644
--- a/doc/device-tree-bindings/input/cros-ec-keyb.txt
+++ b/doc/device-tree-bindings/input/cros-ec-keyb.txt
@@ -1,45 +1,38 @@
-CROS_EC Keyboard
+ChromeOS EC Keyboard
-The CROS_EC (Matrix Keyboard Protocol) allows communcation with a secondary
-micro used for keyboard, and possible other features.
+Google's ChromeOS EC Keyboard is a simple matrix keyboard implemented on
+a separate EC (Embedded Controller) device. It provides a message for reading
+key scans from the EC. These are then converted into keycodes for processing
+by the kernel.
-The CROS_EC keyboard uses this protocol to receive key scans and produce input
-in U-Boot.
+This binding is based on matrix-keymap.txt and extends/modifies it as follows:
-Required properties :
-- compatible : "google,cros-ec-keyb"
-- google,key-rows : Number of key rows
-- google,key-columns : Number of key columns
+Required properties:
+- compatible: "google,cros-ec-keyb"
-Optional properties, in addition to those specified by the shared
-matrix-keyboard bindings:
+Optional properties:
+- google,needs-ghost-filter: True to enable a ghost filter for the matrix
+keyboard. This is recommended if the EC does not have its own logic or
+hardware for this.
-- linux,fn-keymap: a second keymap, same specification as the
- matrix-keyboard-controller spec but to be used when the KEY_FN modifier
- key is pressed.
-- google,repeat-delay-ms : delay in milliseconds before repeat starts
-- google,repeat-rate-ms : delay between each subsequent key press
-- google,ghost-filter : enable ghost filtering for this device
-Example, taken from daisy:
+Example:
cros-ec-keyb {
compatible = "google,cros-ec-keyb";
- google,key-rows = <8>;
- google,key-columns = <13>;
- google,ghost-filter;
- google,repeat-delay-ms = <240>;
- google,repeat-rate-ms = <30>;
+ keypad,num-rows = <8>;
+ keypad,num-columns = <13>;
+ google,needs-ghost-filter;
/*
- * Keymap entries take the form of 0xRRCCKKKK where
- * RR=Row CC=Column KKKK=Key Code
- * The values below are for a US keyboard layout and
- * are taken from the Linux driver. Note that the
- * 102ND key is not used for US keyboards.
- */
+ * Keymap entries take the form of 0xRRCCKKKK where
+ * RR=Row CC=Column KKKK=Key Code
+ * The values below are for a US keyboard layout and
+ * are taken from the Linux driver. Note that the
+ * 102ND key is not used for US keyboards.
+ */
linux,keymap = <
/* CAPSLCK F1 B F10 */
- 0x0001003a 0x0002003c 0x00030030 0x00040044
+ 0x0001003a 0x0002003b 0x00030030 0x00040044
/* N = R_ALT ESC */
0x00060031 0x0008000d 0x000a0064 0x01010001
/* F4 G F7 H */