xref: /OK3568_Linux_fs/u-boot/include/key_matrix.h (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun /*
2*4882a593Smuzhiyun  * Keyboard matrix helper functions
3*4882a593Smuzhiyun  *
4*4882a593Smuzhiyun  * Copyright (c) 2012 The Chromium OS Authors.
5*4882a593Smuzhiyun  *
6*4882a593Smuzhiyun  * SPDX-License-Identifier:	GPL-2.0+
7*4882a593Smuzhiyun  */
8*4882a593Smuzhiyun 
9*4882a593Smuzhiyun #ifndef _KEY_MATRIX_H
10*4882a593Smuzhiyun #define _KEY_MATRIX_H
11*4882a593Smuzhiyun 
12*4882a593Smuzhiyun #include <common.h>
13*4882a593Smuzhiyun 
14*4882a593Smuzhiyun /* Information about a matrix keyboard */
15*4882a593Smuzhiyun struct key_matrix {
16*4882a593Smuzhiyun 	/* Dimensions of the keyboard matrix, in rows and columns */
17*4882a593Smuzhiyun 	int num_rows;
18*4882a593Smuzhiyun 	int num_cols;
19*4882a593Smuzhiyun 	int key_count;	/* number of keys in the matrix (= rows * cols) */
20*4882a593Smuzhiyun 
21*4882a593Smuzhiyun 	/*
22*4882a593Smuzhiyun 	 * Information about keycode mappings. The plain_keycode array must
23*4882a593Smuzhiyun 	 * exist but fn may be NULL in which case it is not decoded.
24*4882a593Smuzhiyun 	 */
25*4882a593Smuzhiyun 	const u8 *plain_keycode;        /* key code for each row / column */
26*4882a593Smuzhiyun 	const u8 *fn_keycode;           /* ...when Fn held down */
27*4882a593Smuzhiyun 	int fn_pos;                     /* position of Fn key in key (or -1) */
28*4882a593Smuzhiyun 	int ghost_filter;		/* non-zero to enable ghost filter */
29*4882a593Smuzhiyun };
30*4882a593Smuzhiyun 
31*4882a593Smuzhiyun /* Information about a particular key (row, column pair) in the matrix */
32*4882a593Smuzhiyun struct key_matrix_key {
33*4882a593Smuzhiyun 	uint8_t row;	/* row number (0 = first) */
34*4882a593Smuzhiyun 	uint8_t col;	/* column number (0 = first) */
35*4882a593Smuzhiyun 	uint8_t valid;	/* 1 if valid, 0 to ignore this */
36*4882a593Smuzhiyun };
37*4882a593Smuzhiyun 
38*4882a593Smuzhiyun /**
39*4882a593Smuzhiyun  * Decode a set of pressed keys into key codes
40*4882a593Smuzhiyun  *
41*4882a593Smuzhiyun  * Given a list of keys that are pressed, this converts this list into
42*4882a593Smuzhiyun  * a list of key codes. Each of the keys has a valid flag, which can be
43*4882a593Smuzhiyun  * used to mark a particular key as invalid (so that it is ignored).
44*4882a593Smuzhiyun  *
45*4882a593Smuzhiyun  * The plain keymap is used, unless the Fn key is detected along the way,
46*4882a593Smuzhiyun  * at which point we switch to the Fn key map.
47*4882a593Smuzhiyun  *
48*4882a593Smuzhiyun  * If key ghosting is detected, we simply ignore the keys and return 0.
49*4882a593Smuzhiyun  *
50*4882a593Smuzhiyun  * @param config        Keyboard matrix config
51*4882a593Smuzhiyun  * @param keys		List of keys to process (each is row, col)
52*4882a593Smuzhiyun  * @param num_keys	Number of keys to process
53*4882a593Smuzhiyun  * @param keycode	Returns a list of key codes, decoded from input
54*4882a593Smuzhiyun  * @param max_keycodes	Size of key codes array (suggest 8)
55*4882a593Smuzhiyun  *
56*4882a593Smuzhiyun  */
57*4882a593Smuzhiyun int key_matrix_decode(struct key_matrix *config, struct key_matrix_key *keys,
58*4882a593Smuzhiyun 		      int num_keys, int keycode[], int max_keycodes);
59*4882a593Smuzhiyun 
60*4882a593Smuzhiyun /**
61*4882a593Smuzhiyun  * Read the keyboard configuration out of the fdt.
62*4882a593Smuzhiyun  *
63*4882a593Smuzhiyun  * Decode properties of named "linux,<type>keymap" where <type> is either
64*4882a593Smuzhiyun  * empty, or "fn-". Then set up the plain key map (and the FN keymap if
65*4882a593Smuzhiyun  * present).
66*4882a593Smuzhiyun  *
67*4882a593Smuzhiyun  * @param config        Keyboard matrix config
68*4882a593Smuzhiyun  * @param blob          FDT blob
69*4882a593Smuzhiyun  * @param node          Node containing compatible data
70*4882a593Smuzhiyun  * @return 0 if ok, -1 on error
71*4882a593Smuzhiyun  */
72*4882a593Smuzhiyun int key_matrix_decode_fdt(struct udevice *dev, struct key_matrix *config);
73*4882a593Smuzhiyun 
74*4882a593Smuzhiyun /**
75*4882a593Smuzhiyun  * Set up a new key matrix.
76*4882a593Smuzhiyun  *
77*4882a593Smuzhiyun  * @param config	Keyboard matrix config
78*4882a593Smuzhiyun  * @param rows		Number of rows in key matrix
79*4882a593Smuzhiyun  * @param cols		Number of columns in key matrix
80*4882a593Smuzhiyun  * @param ghost_filter	Non-zero to enable ghost filtering
81*4882a593Smuzhiyun  * @return 0 if ok, -1 on error
82*4882a593Smuzhiyun  */
83*4882a593Smuzhiyun int key_matrix_init(struct key_matrix *config, int rows, int cols,
84*4882a593Smuzhiyun 		    int ghost_filter);
85*4882a593Smuzhiyun 
86*4882a593Smuzhiyun #endif
87