/* * Keyboard matrix helper functions * * Copyright (c) 2012 The Chromium OS Authors. * See file CREDITS for list of people who contributed to this * project. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License as * published by the Free Software Foundation; either version 2 of * the License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, * MA 02111-1307 USA */ #ifndef _KEY_MATRIX_H #define _KEY_MATRIX_H #include <common.h> /* Information about a matrix keyboard */ struct key_matrix { /* Dimensions of the keyboard matrix, in rows and columns */ int num_rows; int num_cols; int key_count; /* number of keys in the matrix (= rows * cols) */ /* * Information about keycode mappings. The plain_keycode array must * exist but fn may be NULL in which case it is not decoded. */ const u8 *plain_keycode; /* key code for each row / column */ const u8 *fn_keycode; /* ...when Fn held down */ int fn_pos; /* position of Fn key in key (or -1) */ }; /* Information about a particular key (row, column pair) in the matrix */ struct key_matrix_key { uint8_t row; /* row number (0 = first) */ uint8_t col; /* column number (0 = first) */ uint8_t valid; /* 1 if valid, 0 to ignore this */ }; /** * Decode a set of pressed keys into key codes * * Given a list of keys that are pressed, this converts this list into * a list of key codes. Each of the keys has a valid flag, which can be * used to mark a particular key as invalid (so that it is ignored). * * The plain keymap is used, unless the Fn key is detected along the way, * at which point we switch to the Fn key map. * * If key ghosting is detected, we simply ignore the keys and return 0. * * @param config Keyboard matrix config * @param keys List of keys to process (each is row, col) * @param num_keys Number of keys to process * @param keycode Returns a list of key codes, decoded from input * @param max_keycodes Size of key codes array (suggest 8) * */ int key_matrix_decode(struct key_matrix *config, struct key_matrix_key *keys, int num_keys, int keycode[], int max_keycodes); /** * Read the keyboard configuration out of the fdt. * * Decode properties of named "linux,<type>keymap" where <type> is either * empty, or "fn-". Then set up the plain key map (and the FN keymap if * present). * * @param config Keyboard matrix config * @param blob FDT blob * @param node Node containing compatible data * @return 0 if ok, -1 on error */ int key_matrix_decode_fdt(struct key_matrix *config, const void *blob, int node); /** * Set up a new key matrix. * * @param config Keyboard matrix config * @param rows Number of rows in key matrix * @param cols Number of columns in key matrix * @return 0 if ok, -1 on error */ int key_matrix_init(struct key_matrix *config, int rows, int cols); #endif