Kernel-4.18.0-80.el8_brcm,bcm-keypa

• Broadcom Keypad Controller device tree bindings

Broadcom Keypad controller is used to interface a SoC with a matrix-type
keypad device. The keypad controller supports multiple row and column lines.
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 “brcm,bcm-keypad”

• reg: physical base address of the controller and length of memory mapped
  region.

• interrupts: The interrupt number to the cpu.

Board Specific Properties:

• keypad,num-rows: Number of row lines connected to the keypad
  controller.

• keypad,num-columns: Number of column lines connected to the
  keypad controller.

• col-debounce-filter-period: The debounce period for the Column filter.

  KEYPAD_DEBOUNCE_1_ms = 0
  KEYPAD_DEBOUNCE_2_ms = 1
  KEYPAD_DEBOUNCE_4_ms = 2
  KEYPAD_DEBOUNCE_8_ms = 3
  KEYPAD_DEBOUNCE_16_ms = 4
  KEYPAD_DEBOUNCE_32_ms = 5
  KEYPAD_DEBOUNCE_64_ms = 6
  KEYPAD_DEBOUNCE_128_ms = 7

• status-debounce-filter-period: The debounce period for the Status filter.

  KEYPAD_DEBOUNCE_1_ms = 0
  KEYPAD_DEBOUNCE_2_ms = 1
  KEYPAD_DEBOUNCE_4_ms = 2
  KEYPAD_DEBOUNCE_8_ms = 3
  KEYPAD_DEBOUNCE_16_ms = 4
  KEYPAD_DEBOUNCE_32_ms = 5
  KEYPAD_DEBOUNCE_64_ms = 6
  KEYPAD_DEBOUNCE_128_ms = 7

• row-output-enabled: An optional property indicating whether the row or
  column is being used as output. If specified the row is being used
  as the output. Else defaults to column.

• pull-up-enabled: An optional property indicating the Keypad scan mode.
  If specified implies the keypad scan pull-up has been enabled.

• autorepeat: Boolean, Enable auto repeat feature of Linux input

  subsystem (optional).
  

• linux,keymap: The keymap for keys as described in the binding document
  devicetree/bindings/input/matrix-keymap.txt.

Example:
#include “dt-bindings/input/input.h”

/ {
keypad: keypad@180ac000 {
/* Required SoC specific properties */
compatible = “brcm,bcm-keypad”;

    /* Required Board specific properties */
    keypad,num-rows = <5>;
    keypad,num-columns = <5>;

    linux,keymap = <MATRIX_KEY(0x00, 0x02, KEY_F) /* key_forward */
    MATRIX_KEY(0x00, 0x03, KEY_HOME) /* key_home */
    MATRIX_KEY(0x00, 0x04, KEY_M) /* key_message */
    MATRIX_KEY(0x01, 0x00, KEY_A) /* key_contacts */
    MATRIX_KEY(0x01, 0x01, KEY_1) /* key_1 */
    MATRIX_KEY(0x01, 0x02, KEY_2) /* key_2 */
    MATRIX_KEY(0x01, 0x03, KEY_3) /* key_3 */
    MATRIX_KEY(0x01, 0x04, KEY_S) /* key_speaker */
    MATRIX_KEY(0x02, 0x00, KEY_P) /* key_phone */
    MATRIX_KEY(0x02, 0x01, KEY_4) /* key_4 */
    MATRIX_KEY(0x02, 0x02, KEY_5) /* key_5 */
    MATRIX_KEY(0x02, 0x03, KEY_6) /* key_6 */
    MATRIX_KEY(0x02, 0x04, KEY_VOLUMEUP) /* key_vol_up */
    MATRIX_KEY(0x03, 0x00, KEY_C) /* key_call_log */
    MATRIX_KEY(0x03, 0x01, KEY_7) /* key_7 */
    MATRIX_KEY(0x03, 0x02, KEY_8) /* key_8 */
    MATRIX_KEY(0x03, 0x03, KEY_9) /* key_9 */
    MATRIX_KEY(0x03, 0x04, KEY_VOLUMEDOWN) /* key_vol_down */
    MATRIX_KEY(0x04, 0x00, KEY_H) /* key_headset */
    MATRIX_KEY(0x04, 0x01, KEY_KPASTERISK) /* key_* */
    MATRIX_KEY(0x04, 0x02, KEY_0) /* key_0 */
    MATRIX_KEY(0x04, 0x03, KEY_GRAVE) /* key_# */
    MATRIX_KEY(0x04, 0x04, KEY_MUTE) /* key_mute */
    >;

    /* Optional board specific properties */
    col-debounce-filter-period = <5>;
    row-output-enabled;
    pull-up-enabled;

};

};