1 /* 2 * Generic support for sparse keymaps 3 * 4 * Copyright (c) 2009 Dmitry Torokhov 5 * 6 * Derived from wistron button driver: 7 * Copyright (C) 2005 Miloslav Trmac <[email protected]> 8 * Copyright (C) 2005 Bernhard Rosenkraenzer <[email protected]> 9 * Copyright (C) 2005 Dmitry Torokhov <[email protected]> 10 * 11 * This program is free software; you can redistribute it and/or modify it 12 * under the terms of the GNU General Public License version 2 as published by 13 * the Free Software Foundation. 14 */ 15 16 #include <linux/input.h> 17 #include <linux/input/sparse-keymap.h> 18 #include <linux/slab.h> 19 20 MODULE_AUTHOR("Dmitry Torokhov <[email protected]>"); 21 MODULE_DESCRIPTION("Generic support for sparse keymaps"); 22 MODULE_LICENSE("GPL v2"); 23 MODULE_VERSION("0.1"); 24 25 /** 26 * sparse_keymap_entry_from_scancode - perform sparse keymap lookup 27 * @dev: Input device using sparse keymap 28 * @code: Scan code 29 * 30 * This function is used to perform &struct key_entry lookup in an 31 * input device using sparse keymap. 32 */ 33 struct key_entry *sparse_keymap_entry_from_scancode(struct input_dev *dev, 34 unsigned int code) 35 { 36 struct key_entry *key; 37 38 for (key = dev->keycode; key->type != KE_END; key++) 39 if (code == key->code) 40 return key; 41 42 return NULL; 43 } 44 EXPORT_SYMBOL(sparse_keymap_entry_from_scancode); 45 46 /** 47 * sparse_keymap_entry_from_keycode - perform sparse keymap lookup 48 * @dev: Input device using sparse keymap 49 * @keycode: Key code 50 * 51 * This function is used to perform &struct key_entry lookup in an 52 * input device using sparse keymap. 53 */ 54 struct key_entry *sparse_keymap_entry_from_keycode(struct input_dev *dev, 55 unsigned int keycode) 56 { 57 struct key_entry *key; 58 59 for (key = dev->keycode; key->type != KE_END; key++) 60 if (key->type == KE_KEY && keycode == key->keycode) 61 return key; 62 63 return NULL; 64 } 65 EXPORT_SYMBOL(sparse_keymap_entry_from_keycode); 66 67 static int sparse_keymap_getkeycode(struct input_dev *dev, 68 unsigned int scancode, 69 unsigned int *keycode) 70 { 71 const struct key_entry *key = 72 sparse_keymap_entry_from_scancode(dev, scancode); 73 74 if (key && key->type == KE_KEY) { 75 *keycode = key->keycode; 76 return 0; 77 } 78 79 return -EINVAL; 80 } 81 82 static int sparse_keymap_setkeycode(struct input_dev *dev, 83 unsigned int scancode, 84 unsigned int keycode) 85 { 86 struct key_entry *key; 87 int old_keycode; 88 89 if (keycode < 0 || keycode > KEY_MAX) 90 return -EINVAL; 91 92 key = sparse_keymap_entry_from_scancode(dev, scancode); 93 if (key && key->type == KE_KEY) { 94 old_keycode = key->keycode; 95 key->keycode = keycode; 96 set_bit(keycode, dev->keybit); 97 if (!sparse_keymap_entry_from_keycode(dev, old_keycode)) 98 clear_bit(old_keycode, dev->keybit); 99 return 0; 100 } 101 102 return -EINVAL; 103 } 104 105 /** 106 * sparse_keymap_setup - set up sparse keymap for an input device 107 * @dev: Input device 108 * @keymap: Keymap in form of array of &key_entry structures ending 109 * with %KE_END type entry 110 * @setup: Function that can be used to adjust keymap entries 111 * depending on device's deeds, may be %NULL 112 * 113 * The function calculates size and allocates copy of the original 114 * keymap after which sets up input device event bits appropriately. 115 * Before destroying input device allocated keymap should be freed 116 * with a call to sparse_keymap_free(). 117 */ 118 int sparse_keymap_setup(struct input_dev *dev, 119 const struct key_entry *keymap, 120 int (*setup)(struct input_dev *, struct key_entry *)) 121 { 122 size_t map_size = 1; /* to account for the last KE_END entry */ 123 const struct key_entry *e; 124 struct key_entry *map, *entry; 125 int i; 126 int error; 127 128 for (e = keymap; e->type != KE_END; e++) 129 map_size++; 130 131 map = kcalloc(map_size, sizeof (struct key_entry), GFP_KERNEL); 132 if (!map) 133 return -ENOMEM; 134 135 memcpy(map, keymap, map_size * sizeof (struct key_entry)); 136 137 for (i = 0; i < map_size; i++) { 138 entry = &map[i]; 139 140 if (setup) { 141 error = setup(dev, entry); 142 if (error) 143 goto err_out; 144 } 145 146 switch (entry->type) { 147 case KE_KEY: 148 __set_bit(EV_KEY, dev->evbit); 149 __set_bit(entry->keycode, dev->keybit); 150 break; 151 152 case KE_SW: 153 __set_bit(EV_SW, dev->evbit); 154 __set_bit(entry->sw.code, dev->swbit); 155 break; 156 } 157 } 158 159 dev->keycode = map; 160 dev->keycodemax = map_size; 161 dev->getkeycode = sparse_keymap_getkeycode; 162 dev->setkeycode = sparse_keymap_setkeycode; 163 164 return 0; 165 166 err_out: 167 kfree(keymap); 168 return error; 169 170 } 171 EXPORT_SYMBOL(sparse_keymap_setup); 172 173 /** 174 * sparse_keymap_free - free memory allocated for sparse keymap 175 * @dev: Input device using sparse keymap 176 * 177 * This function is used to free memory allocated by sparse keymap 178 * in an input device that was set up by sparse_keymap_setup(). 179 */ 180 void sparse_keymap_free(struct input_dev *dev) 181 { 182 kfree(dev->keycode); 183 dev->keycode = NULL; 184 dev->keycodemax = 0; 185 dev->getkeycode = NULL; 186 dev->setkeycode = NULL; 187 } 188 EXPORT_SYMBOL(sparse_keymap_free); 189 190 /** 191 * sparse_keymap_report_entry - report event corresponding to given key entry 192 * @dev: Input device for which event should be reported 193 * @ke: key entry describing event 194 * @value: Value that should be reported (ignored by %KE_SW entries) 195 * @autorelease: Signals whether release event should be emitted for %KE_KEY 196 * entries right after reporting press event, ignored by all other 197 * entries 198 * 199 * This function is used to report input event described by given 200 * &struct key_entry. 201 */ 202 void sparse_keymap_report_entry(struct input_dev *dev, const struct key_entry *ke, 203 unsigned int value, bool autorelease) 204 { 205 switch (ke->type) { 206 case KE_KEY: 207 input_report_key(dev, ke->keycode, value); 208 input_sync(dev); 209 if (value && autorelease) { 210 input_report_key(dev, ke->keycode, 0); 211 input_sync(dev); 212 } 213 break; 214 215 case KE_SW: 216 value = ke->sw.value; 217 /* fall through */ 218 219 case KE_VSW: 220 input_report_switch(dev, ke->sw.code, value); 221 break; 222 } 223 } 224 EXPORT_SYMBOL(sparse_keymap_report_entry); 225 226 /** 227 * sparse_keymap_report_event - report event corresponding to given scancode 228 * @dev: Input device using sparse keymap 229 * @code: Scan code 230 * @value: Value that should be reported (ignored by %KE_SW entries) 231 * @autorelease: Signals whether release event should be emitted for %KE_KEY 232 * entries right after reporting press event, ignored by all other 233 * entries 234 * 235 * This function is used to perform lookup in an input device using sparse 236 * keymap and report corresponding event. Returns %true if lookup was 237 * successful and %false otherwise. 238 */ 239 bool sparse_keymap_report_event(struct input_dev *dev, unsigned int code, 240 unsigned int value, bool autorelease) 241 { 242 const struct key_entry *ke = 243 sparse_keymap_entry_from_scancode(dev, code); 244 245 if (ke) { 246 sparse_keymap_report_entry(dev, ke, value, autorelease); 247 return true; 248 } 249 250 return false; 251 } 252 EXPORT_SYMBOL(sparse_keymap_report_event); 253 254