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Diffstat (limited to 'doc/device-tree-bindings/input/cros-ec-keyb.txt')
| -rw-r--r-- | doc/device-tree-bindings/input/cros-ec-keyb.txt | 53 |
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 */ |