2 * Helpers for matrix keyboard bindings
4 * Copyright (C) 2012 Google, Inc
7 * Olof Johansson <olof@lixom.net>
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.
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.
20 #include <linux/device.h>
21 #include <linux/gfp.h>
22 #include <linux/kernel.h>
23 #include <linux/types.h>
24 #include <linux/input.h>
26 #include <linux/export.h>
27 #include <linux/module.h>
28 #include <linux/input/matrix_keypad.h>
30 static bool matrix_keypad_map_key(struct input_dev *input_dev,
31 unsigned int rows, unsigned int cols,
32 unsigned int row_shift, unsigned int key)
34 unsigned short *keymap = input_dev->keycode;
35 unsigned int row = KEY_ROW(key);
36 unsigned int col = KEY_COL(key);
37 unsigned short code = KEY_VAL(key);
39 if (row >= rows || col >= cols) {
40 dev_err(input_dev->dev.parent,
41 "%s: invalid keymap entry 0x%x (row: %d, col: %d, rows: %d, cols: %d)\n",
42 __func__, key, row, col, rows, cols);
46 keymap[MATRIX_SCAN_CODE(row, col, row_shift)] = code;
47 __set_bit(code, input_dev->keybit);
53 int matrix_keypad_parse_of_params(struct device *dev,
54 unsigned int *rows, unsigned int *cols)
56 struct device_node *np = dev->of_node;
59 dev_err(dev, "missing DT data");
62 of_property_read_u32(np, "keypad,num-rows", rows);
63 of_property_read_u32(np, "keypad,num-columns", cols);
64 if (!*rows || !*cols) {
65 dev_err(dev, "number of keypad rows/columns not specified\n");
72 static int matrix_keypad_parse_of_keymap(const char *propname,
73 unsigned int rows, unsigned int cols,
74 struct input_dev *input_dev)
76 struct device *dev = input_dev->dev.parent;
77 struct device_node *np = dev->of_node;
78 unsigned int row_shift = get_count_order(cols);
79 unsigned int max_keys = rows << row_shift;
80 unsigned int proplen, i, size;
87 propname = "linux,keymap";
89 prop = of_get_property(np, propname, &proplen);
91 dev_err(dev, "OF: %s property not defined in %s\n",
92 propname, np->full_name);
96 if (proplen % sizeof(u32)) {
97 dev_err(dev, "OF: Malformed keycode property %s in %s\n",
98 propname, np->full_name);
102 size = proplen / sizeof(u32);
103 if (size > max_keys) {
104 dev_err(dev, "OF: %s size overflow\n", propname);
108 for (i = 0; i < size; i++) {
109 unsigned int key = be32_to_cpup(prop + i);
111 if (!matrix_keypad_map_key(input_dev, rows, cols,
119 static int matrix_keypad_parse_of_keymap(const char *propname,
120 unsigned int rows, unsigned int cols,
121 struct input_dev *input_dev)
128 * matrix_keypad_build_keymap - convert platform keymap into matrix keymap
129 * @keymap_data: keymap supplied by the platform code
130 * @keymap_name: name of device tree property containing keymap (if device
131 * tree support is enabled).
132 * @rows: number of rows in target keymap array
133 * @cols: number of cols in target keymap array
134 * @keymap: expanded version of keymap that is suitable for use by
135 * matrix keyboard driver
136 * @input_dev: input devices for which we are setting up the keymap
138 * This function converts platform keymap (encoded with KEY() macro) into
139 * an array of keycodes that is suitable for using in a standard matrix
140 * keyboard driver that uses row and col as indices.
142 * If @keymap_data is not supplied and device tree support is enabled
143 * it will attempt load the keymap from property specified by @keymap_name
144 * argument (or "linux,keymap" if @keymap_name is %NULL).
146 * If @keymap is %NULL the function will automatically allocate managed
147 * block of memory to store the keymap. This memory will be associated with
148 * the parent device and automatically freed when device unbinds from the
151 * Callers are expected to set up input_dev->dev.parent before calling this
154 int matrix_keypad_build_keymap(const struct matrix_keymap_data *keymap_data,
155 const char *keymap_name,
156 unsigned int rows, unsigned int cols,
157 unsigned short *keymap,
158 struct input_dev *input_dev)
160 unsigned int row_shift = get_count_order(cols);
161 size_t max_keys = rows << row_shift;
165 if (WARN_ON(!input_dev->dev.parent))
169 keymap = devm_kzalloc(input_dev->dev.parent,
170 max_keys * sizeof(*keymap),
173 dev_err(input_dev->dev.parent,
174 "Unable to allocate memory for keymap");
179 input_dev->keycode = keymap;
180 input_dev->keycodesize = sizeof(*keymap);
181 input_dev->keycodemax = max_keys;
183 __set_bit(EV_KEY, input_dev->evbit);
186 for (i = 0; i < keymap_data->keymap_size; i++) {
187 unsigned int key = keymap_data->keymap[i];
189 if (!matrix_keypad_map_key(input_dev, rows, cols,
194 error = matrix_keypad_parse_of_keymap(keymap_name, rows, cols,
200 __clear_bit(KEY_RESERVED, input_dev->keybit);
204 EXPORT_SYMBOL(matrix_keypad_build_keymap);
206 MODULE_LICENSE("GPL");