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Dmitry Torokhov19328112012-05-10 22:37:08 -07001/*
2 * Helpers for matrix keyboard bindings
3 *
4 * Copyright (C) 2012 Google, Inc
5 *
6 * Author:
7 * Olof Johansson <olof@lixom.net>
8 *
9 * This software is licensed under the terms of the GNU General Public
10 * License version 2, as published by the Free Software Foundation, and
11 * may be copied, distributed, and modified under those terms.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 */
19
Dmitry Torokhovb45c8f32012-05-10 22:37:15 -070020#include <linux/device.h>
Dmitry Torokhov19328112012-05-10 22:37:08 -070021#include <linux/kernel.h>
22#include <linux/types.h>
23#include <linux/input.h>
24#include <linux/of.h>
25#include <linux/export.h>
Dmitry Torokhov19328112012-05-10 22:37:08 -070026#include <linux/input/matrix_keypad.h>
27
Dmitry Torokhovb45c8f32012-05-10 22:37:15 -070028static bool matrix_keypad_map_key(struct input_dev *input_dev,
29 unsigned int rows, unsigned int cols,
30 unsigned int row_shift, unsigned int key)
31{
Dmitry Torokhov86809172012-05-24 01:10:20 -070032 unsigned short *keymap = input_dev->keycode;
Dmitry Torokhovb45c8f32012-05-10 22:37:15 -070033 unsigned int row = KEY_ROW(key);
34 unsigned int col = KEY_COL(key);
35 unsigned short code = KEY_VAL(key);
36
37 if (row >= rows || col >= cols) {
38 dev_err(input_dev->dev.parent,
39 "%s: invalid keymap entry 0x%x (row: %d, col: %d, rows: %d, cols: %d)\n",
40 __func__, key, row, col, rows, cols);
41 return false;
42 }
43
44 keymap[MATRIX_SCAN_CODE(row, col, row_shift)] = code;
45 __set_bit(code, input_dev->keybit);
46
47 return true;
48}
49
50#ifdef CONFIG_OF
51static int matrix_keypad_parse_of_keymap(const char *propname,
52 unsigned int rows, unsigned int cols,
53 struct input_dev *input_dev)
54{
55 struct device *dev = input_dev->dev.parent;
56 struct device_node *np = dev->of_node;
57 unsigned int row_shift = get_count_order(cols);
58 unsigned int max_keys = rows << row_shift;
59 unsigned int proplen, i, size;
60 const __be32 *prop;
61
62 if (!np)
63 return -ENOENT;
64
65 if (!propname)
66 propname = "linux,keymap";
67
68 prop = of_get_property(np, propname, &proplen);
69 if (!prop) {
70 dev_err(dev, "OF: %s property not defined in %s\n",
71 propname, np->full_name);
72 return -ENOENT;
73 }
74
75 if (proplen % sizeof(u32)) {
76 dev_err(dev, "OF: Malformed keycode property %s in %s\n",
77 propname, np->full_name);
78 return -EINVAL;
79 }
80
81 size = proplen / sizeof(u32);
82 if (size > max_keys) {
83 dev_err(dev, "OF: %s size overflow\n", propname);
84 return -EINVAL;
85 }
86
87 for (i = 0; i < size; i++) {
88 unsigned int key = be32_to_cpup(prop + i);
89
90 if (!matrix_keypad_map_key(input_dev, rows, cols,
91 row_shift, key))
92 return -EINVAL;
93 }
94
95 return 0;
96}
97#else
98static int matrix_keypad_parse_of_keymap(const char *propname,
99 unsigned int rows, unsigned int cols,
100 struct input_dev *input_dev)
101{
102 return -ENOSYS;
103}
104#endif
Dmitry Torokhov19328112012-05-10 22:37:08 -0700105
106/**
107 * matrix_keypad_build_keymap - convert platform keymap into matrix keymap
108 * @keymap_data: keymap supplied by the platform code
109 * @keymap_name: name of device tree property containing keymap (if device
110 * tree support is enabled).
111 * @rows: number of rows in target keymap array
112 * @cols: number of cols in target keymap array
113 * @keymap: expanded version of keymap that is suitable for use by
114 * matrix keyboard driver
115 * @input_dev: input devices for which we are setting up the keymap
116 *
117 * This function converts platform keymap (encoded with KEY() macro) into
118 * an array of keycodes that is suitable for using in a standard matrix
119 * keyboard driver that uses row and col as indices.
Dmitry Torokhovb45c8f32012-05-10 22:37:15 -0700120 *
121 * If @keymap_data is not supplied and device tree support is enabled
122 * it will attempt load the keymap from property specified by @keymap_name
123 * argument (or "linux,keymap" if @keymap_name is %NULL).
124 *
125 * Callers are expected to set up input_dev->dev.parent before calling this
126 * function.
Dmitry Torokhov19328112012-05-10 22:37:08 -0700127 */
128int matrix_keypad_build_keymap(const struct matrix_keymap_data *keymap_data,
129 const char *keymap_name,
130 unsigned int rows, unsigned int cols,
131 unsigned short *keymap,
132 struct input_dev *input_dev)
133{
134 unsigned int row_shift = get_count_order(cols);
135 int i;
Dmitry Torokhovb45c8f32012-05-10 22:37:15 -0700136 int error;
Dmitry Torokhov19328112012-05-10 22:37:08 -0700137
138 input_dev->keycode = keymap;
139 input_dev->keycodesize = sizeof(*keymap);
140 input_dev->keycodemax = rows << row_shift;
141
142 __set_bit(EV_KEY, input_dev->evbit);
143
Dmitry Torokhovb45c8f32012-05-10 22:37:15 -0700144 if (keymap_data) {
145 for (i = 0; i < keymap_data->keymap_size; i++) {
146 unsigned int key = keymap_data->keymap[i];
Dmitry Torokhov19328112012-05-10 22:37:08 -0700147
Dmitry Torokhovb45c8f32012-05-10 22:37:15 -0700148 if (!matrix_keypad_map_key(input_dev, rows, cols,
149 row_shift, key))
150 return -EINVAL;
Dmitry Torokhov19328112012-05-10 22:37:08 -0700151 }
Dmitry Torokhovb45c8f32012-05-10 22:37:15 -0700152 } else {
153 error = matrix_keypad_parse_of_keymap(keymap_name, rows, cols,
154 input_dev);
155 if (error)
156 return error;
Dmitry Torokhov19328112012-05-10 22:37:08 -0700157 }
Dmitry Torokhovb45c8f32012-05-10 22:37:15 -0700158
Dmitry Torokhov19328112012-05-10 22:37:08 -0700159 __clear_bit(KEY_RESERVED, input_dev->keybit);
160
161 return 0;
162}
163EXPORT_SYMBOL(matrix_keypad_build_keymap);