| 1 | |
| 2 | * Helpers for matrix keyboard bindings
|
| 3 | *
|
| 4 | * Copyright (C) 2012 Google, Inc
|
| 5 | *
|
| 6 | * Author:
|
| 7 | * Olof Johansson <[email protected]>
|
| 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 | #include <linux/device.h>
|
| 20 | #include <linux/export.h>
|
| 21 | #include <linux/gfp.h>
|
| 22 | #include <linux/input.h>
|
| 23 | #include <linux/input/matrix_keypad.h>
|
| 24 | #include <linux/kernel.h>
|
| 25 | #include <linux/module.h>
|
| 26 | #include <linux/property.h>
|
| 27 | #include <linux/slab.h>
|
| 28 | #include <linux/types.h>
|
| 29 |
|
| 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)
|
| 33 | {
|
| 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);
|
| 38 |
|
| 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);
|
| 43 | return false;
|
| 44 | }
|
| 45 |
|
| 46 | keymap[MATRIX_SCAN_CODE(row, col, row_shift)] = code;
|
| 47 | __set_bit(code, input_dev->keybit);
|
| 48 |
|
| 49 | return true;
|
| 50 | }
|
| 51 |
|
| 52 | |
| 53 | * matrix_keypad_parse_properties() - Read properties of matrix keypad
|
| 54 | *
|
| 55 | * @dev: Device containing properties
|
| 56 | * @rows: Returns number of matrix rows
|
| 57 | * @cols: Returns number of matrix columns
|
| 58 | * @return 0 if OK, <0 on error
|
| 59 |
|
| 60 | int matrix_keypad_parse_properties(struct device *dev,
|
| 61 | unsigned int *rows, unsigned int *cols)
|
| 62 | {
|
| 63 | *rows = *cols = 0;
|
| 64 |
|
| 65 | device_property_read_u32(dev, "keypad,num-rows", rows);
|
| 66 | device_property_read_u32(dev, "keypad,num-columns", cols);
|
| 67 |
|
| 68 | if (!*rows || !*cols) {
|
| 69 | dev_err(dev, "number of keypad rows/columns not specified\n");
|
| 70 | return -EINVAL;
|
| 71 | }
|
| 72 |
|
| 73 | return 0;
|
| 74 | }
|
| 75 | EXPORT_SYMBOL_GPL(matrix_keypad_parse_properties);
|
| 76 |
|
| 77 | static int matrix_keypad_parse_keymap(const char *propname,
|
| 78 | unsigned int rows, unsigned int cols,
|
| 79 | struct input_dev *input_dev)
|
| 80 | {
|
| 81 | struct device *dev = input_dev->dev.parent;
|
| 82 | unsigned int row_shift = get_count_order(cols);
|
| 83 | unsigned int max_keys = rows << row_shift;
|
| 84 | u32 *keys;
|
| 85 | int i;
|
| 86 | int size;
|
| 87 | int retval;
|
| 88 |
|
| 89 | if (!propname)
|
| 90 | propname = "linux,keymap";
|
| 91 |
|
| 92 | size = device_property_read_u32_array(dev, propname, NULL, 0);
|
| 93 | if (size <= 0) {
|
| 94 | dev_err(dev, "missing or malformed property %s: %d\n",
|
| 95 | propname, size);
|
| 96 | return size < 0 ? size : -EINVAL;
|
| 97 | }
|
| 98 |
|
| 99 | if (size > max_keys) {
|
| 100 | dev_err(dev, "%s size overflow (%d vs max %u)\n",
|
| 101 | propname, size, max_keys);
|
| 102 | return -EINVAL;
|
| 103 | }
|
| 104 |
|
| 105 | keys = kmalloc_array(size, sizeof(u32), GFP_KERNEL);
|
| 106 | if (!keys)
|
| 107 | return -ENOMEM;
|
| 108 |
|
| 109 | retval = device_property_read_u32_array(dev, propname, keys, size);
|
| 110 | if (retval) {
|
| 111 | dev_err(dev, "failed to read %s property: %d\n",
|
| 112 | propname, retval);
|
| 113 | goto out;
|
| 114 | }
|
| 115 |
|
| 116 | for (i = 0; i < size; i++) {
|
| 117 | if (!matrix_keypad_map_key(input_dev, rows, cols,
|
| 118 | row_shift, keys[i])) {
|
| 119 | retval = -EINVAL;
|
| 120 | goto out;
|
| 121 | }
|
| 122 | }
|
| 123 |
|
| 124 | retval = 0;
|
| 125 |
|
| 126 | out:
|
| 127 | kfree(keys);
|
| 128 | return retval;
|
| 129 | }
|
| 130 |
|
| 131 | |
| 132 | * matrix_keypad_build_keymap - convert platform keymap into matrix keymap
|
| 133 | * @keymap_data: keymap supplied by the platform code
|
| 134 | * @keymap_name: name of device tree property containing keymap (if device
|
| 135 | * tree support is enabled).
|
| 136 | * @rows: number of rows in target keymap array
|
| 137 | * @cols: number of cols in target keymap array
|
| 138 | * @keymap: expanded version of keymap that is suitable for use by
|
| 139 | * matrix keyboard driver
|
| 140 | * @input_dev: input devices for which we are setting up the keymap
|
| 141 | *
|
| 142 | * This function converts platform keymap (encoded with KEY() macro) into
|
| 143 | * an array of keycodes that is suitable for using in a standard matrix
|
| 144 | * keyboard driver that uses row and col as indices.
|
| 145 | *
|
| 146 | * If @keymap_data is not supplied and device tree support is enabled
|
| 147 | * it will attempt load the keymap from property specified by @keymap_name
|
| 148 | * argument (or "linux,keymap" if @keymap_name is %NULL).
|
| 149 | *
|
| 150 | * If @keymap is %NULL the function will automatically allocate managed
|
| 151 | * block of memory to store the keymap. This memory will be associated with
|
| 152 | * the parent device and automatically freed when device unbinds from the
|
| 153 | * driver.
|
| 154 | *
|
| 155 | * Callers are expected to set up input_dev->dev.parent before calling this
|
| 156 | * function.
|
| 157 |
|
| 158 | int matrix_keypad_build_keymap(const struct matrix_keymap_data *keymap_data,
|
| 159 | const char *keymap_name,
|
| 160 | unsigned int rows, unsigned int cols,
|
| 161 | unsigned short *keymap,
|
| 162 | struct input_dev *input_dev)
|
| 163 | {
|
| 164 | unsigned int row_shift = get_count_order(cols);
|
| 165 | size_t max_keys = rows << row_shift;
|
| 166 | int i;
|
| 167 | int error;
|
| 168 |
|
| 169 | if (WARN_ON(!input_dev->dev.parent))
|
| 170 | return -EINVAL;
|
| 171 |
|
| 172 | if (!keymap) {
|
| 173 | keymap = devm_kzalloc(input_dev->dev.parent,
|
| 174 | max_keys * sizeof(*keymap),
|
| 175 | GFP_KERNEL);
|
| 176 | if (!keymap) {
|
| 177 | dev_err(input_dev->dev.parent,
|
| 178 | "Unable to allocate memory for keymap");
|
| 179 | return -ENOMEM;
|
| 180 | }
|
| 181 | }
|
| 182 |
|
| 183 | input_dev->keycode = keymap;
|
| 184 | input_dev->keycodesize = sizeof(*keymap);
|
| 185 | input_dev->keycodemax = max_keys;
|
| 186 |
|
| 187 | __set_bit(EV_KEY, input_dev->evbit);
|
| 188 |
|
| 189 | if (keymap_data) {
|
| 190 | for (i = 0; i < keymap_data->keymap_size; i++) {
|
| 191 | unsigned int key = keymap_data->keymap[i];
|
| 192 |
|
| 193 | if (!matrix_keypad_map_key(input_dev, rows, cols,
|
| 194 | row_shift, key))
|
| 195 | return -EINVAL;
|
| 196 | }
|
| 197 | } else {
|
| 198 | error = matrix_keypad_parse_keymap(keymap_name, rows, cols,
|
| 199 | input_dev);
|
| 200 | if (error)
|
| 201 | return error;
|
| 202 | }
|
| 203 |
|
| 204 | __clear_bit(KEY_RESERVED, input_dev->keybit);
|
| 205 |
|
| 206 | return 0;
|
| 207 | }
|
| 208 | EXPORT_SYMBOL(matrix_keypad_build_keymap);
|
| 209 |
|
| 210 | MODULE_LICENSE("GPL");
|