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 <mitr@volny.cz> 8 * Copyright (C) 2005 Bernhard Rosenkraenzer <bero@arklinux.org> 9 * Copyright (C) 2005 Dmitry Torokhov <dtor@mail.ru> 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 <dtor@mail.ru>"); 21 MODULE_DESCRIPTION("Generic support for sparse keymaps"); 22 MODULE_LICENSE("GPL v2"); 23 MODULE_VERSION("0.1"); 24 25 static unsigned int sparse_keymap_get_key_index(struct input_dev *dev, 26 const struct key_entry *k) 27 { 28 struct key_entry *key; 29 unsigned int idx = 0; 30 31 for (key = dev->keycode; key->type != KE_END; key++) { 32 if (key->type == KE_KEY) { 33 if (key == k) 34 break; 35 idx++; 36 } 37 } 38 39 return idx; 40 } 41 42 static struct key_entry *sparse_keymap_entry_by_index(struct input_dev *dev, 43 unsigned int index) 44 { 45 struct key_entry *key; 46 unsigned int key_cnt = 0; 47 48 for (key = dev->keycode; key->type != KE_END; key++) 49 if (key->type == KE_KEY) 50 if (key_cnt++ == index) 51 return key; 52 53 return NULL; 54 } 55 56 /** 57 * sparse_keymap_entry_from_scancode - perform sparse keymap lookup 58 * @dev: Input device using sparse keymap 59 * @code: Scan code 60 * 61 * This function is used to perform &struct key_entry lookup in an 62 * input device using sparse keymap. 63 */ 64 struct key_entry *sparse_keymap_entry_from_scancode(struct input_dev *dev, 65 unsigned int code) 66 { 67 struct key_entry *key; 68 69 for (key = dev->keycode; key->type != KE_END; key++) 70 if (code == key->code) 71 return key; 72 73 return NULL; 74 } 75 EXPORT_SYMBOL(sparse_keymap_entry_from_scancode); 76 77 /** 78 * sparse_keymap_entry_from_keycode - perform sparse keymap lookup 79 * @dev: Input device using sparse keymap 80 * @keycode: Key code 81 * 82 * This function is used to perform &struct key_entry lookup in an 83 * input device using sparse keymap. 84 */ 85 struct key_entry *sparse_keymap_entry_from_keycode(struct input_dev *dev, 86 unsigned int keycode) 87 { 88 struct key_entry *key; 89 90 for (key = dev->keycode; key->type != KE_END; key++) 91 if (key->type == KE_KEY && keycode == key->keycode) 92 return key; 93 94 return NULL; 95 } 96 EXPORT_SYMBOL(sparse_keymap_entry_from_keycode); 97 98 static struct key_entry *sparse_keymap_locate(struct input_dev *dev, 99 const struct input_keymap_entry *ke) 100 { 101 struct key_entry *key; 102 unsigned int scancode; 103 104 if (ke->flags & INPUT_KEYMAP_BY_INDEX) 105 key = sparse_keymap_entry_by_index(dev, ke->index); 106 else if (input_scancode_to_scalar(ke, &scancode) == 0) 107 key = sparse_keymap_entry_from_scancode(dev, scancode); 108 else 109 key = NULL; 110 111 return key; 112 } 113 114 static int sparse_keymap_getkeycode(struct input_dev *dev, 115 struct input_keymap_entry *ke) 116 { 117 const struct key_entry *key; 118 119 if (dev->keycode) { 120 key = sparse_keymap_locate(dev, ke); 121 if (key && key->type == KE_KEY) { 122 ke->keycode = key->keycode; 123 if (!(ke->flags & INPUT_KEYMAP_BY_INDEX)) 124 ke->index = 125 sparse_keymap_get_key_index(dev, key); 126 ke->len = sizeof(key->code); 127 memcpy(ke->scancode, &key->code, sizeof(key->code)); 128 return 0; 129 } 130 } 131 132 return -EINVAL; 133 } 134 135 static int sparse_keymap_setkeycode(struct input_dev *dev, 136 const struct input_keymap_entry *ke, 137 unsigned int *old_keycode) 138 { 139 struct key_entry *key; 140 141 if (dev->keycode) { 142 key = sparse_keymap_locate(dev, ke); 143 if (key && key->type == KE_KEY) { 144 *old_keycode = key->keycode; 145 key->keycode = ke->keycode; 146 set_bit(ke->keycode, dev->keybit); 147 if (!sparse_keymap_entry_from_keycode(dev, *old_keycode)) 148 clear_bit(*old_keycode, dev->keybit); 149 return 0; 150 } 151 } 152 153 return -EINVAL; 154 } 155 156 /** 157 * sparse_keymap_setup - set up sparse keymap for an input device 158 * @dev: Input device 159 * @keymap: Keymap in form of array of &key_entry structures ending 160 * with %KE_END type entry 161 * @setup: Function that can be used to adjust keymap entries 162 * depending on device's deeds, may be %NULL 163 * 164 * The function calculates size and allocates copy of the original 165 * keymap after which sets up input device event bits appropriately. 166 * Before destroying input device allocated keymap should be freed 167 * with a call to sparse_keymap_free(). 168 */ 169 int sparse_keymap_setup(struct input_dev *dev, 170 const struct key_entry *keymap, 171 int (*setup)(struct input_dev *, struct key_entry *)) 172 { 173 size_t map_size = 1; /* to account for the last KE_END entry */ 174 const struct key_entry *e; 175 struct key_entry *map, *entry; 176 int i; 177 int error; 178 179 for (e = keymap; e->type != KE_END; e++) 180 map_size++; 181 182 map = kcalloc(map_size, sizeof (struct key_entry), GFP_KERNEL); 183 if (!map) 184 return -ENOMEM; 185 186 memcpy(map, keymap, map_size * sizeof (struct key_entry)); 187 188 for (i = 0; i < map_size; i++) { 189 entry = &map[i]; 190 191 if (setup) { 192 error = setup(dev, entry); 193 if (error) 194 goto err_out; 195 } 196 197 switch (entry->type) { 198 case KE_KEY: 199 __set_bit(EV_KEY, dev->evbit); 200 __set_bit(entry->keycode, dev->keybit); 201 break; 202 203 case KE_SW: 204 case KE_VSW: 205 __set_bit(EV_SW, dev->evbit); 206 __set_bit(entry->sw.code, dev->swbit); 207 break; 208 } 209 } 210 211 dev->keycode = map; 212 dev->keycodemax = map_size; 213 dev->getkeycode = sparse_keymap_getkeycode; 214 dev->setkeycode = sparse_keymap_setkeycode; 215 216 return 0; 217 218 err_out: 219 kfree(map); 220 return error; 221 } 222 EXPORT_SYMBOL(sparse_keymap_setup); 223 224 /** 225 * sparse_keymap_free - free memory allocated for sparse keymap 226 * @dev: Input device using sparse keymap 227 * 228 * This function is used to free memory allocated by sparse keymap 229 * in an input device that was set up by sparse_keymap_setup(). 230 * NOTE: It is safe to cal this function while input device is 231 * still registered (however the drivers should care not to try to 232 * use freed keymap and thus have to shut off interrups/polling 233 * before freeing the keymap). 234 */ 235 void sparse_keymap_free(struct input_dev *dev) 236 { 237 unsigned long flags; 238 239 /* 240 * Take event lock to prevent racing with input_get_keycode() 241 * and input_set_keycode() if we are called while input device 242 * is still registered. 243 */ 244 spin_lock_irqsave(&dev->event_lock, flags); 245 246 kfree(dev->keycode); 247 dev->keycode = NULL; 248 dev->keycodemax = 0; 249 250 spin_unlock_irqrestore(&dev->event_lock, flags); 251 } 252 EXPORT_SYMBOL(sparse_keymap_free); 253 254 /** 255 * sparse_keymap_report_entry - report event corresponding to given key entry 256 * @dev: Input device for which event should be reported 257 * @ke: key entry describing event 258 * @value: Value that should be reported (ignored by %KE_SW entries) 259 * @autorelease: Signals whether release event should be emitted for %KE_KEY 260 * entries right after reporting press event, ignored by all other 261 * entries 262 * 263 * This function is used to report input event described by given 264 * &struct key_entry. 265 */ 266 void sparse_keymap_report_entry(struct input_dev *dev, const struct key_entry *ke, 267 unsigned int value, bool autorelease) 268 { 269 switch (ke->type) { 270 case KE_KEY: 271 input_report_key(dev, ke->keycode, value); 272 input_sync(dev); 273 if (value && autorelease) { 274 input_report_key(dev, ke->keycode, 0); 275 input_sync(dev); 276 } 277 break; 278 279 case KE_SW: 280 value = ke->sw.value; 281 /* fall through */ 282 283 case KE_VSW: 284 input_report_switch(dev, ke->sw.code, value); 285 break; 286 } 287 } 288 EXPORT_SYMBOL(sparse_keymap_report_entry); 289 290 /** 291 * sparse_keymap_report_event - report event corresponding to given scancode 292 * @dev: Input device using sparse keymap 293 * @code: Scan code 294 * @value: Value that should be reported (ignored by %KE_SW entries) 295 * @autorelease: Signals whether release event should be emitted for %KE_KEY 296 * entries right after reporting press event, ignored by all other 297 * entries 298 * 299 * This function is used to perform lookup in an input device using sparse 300 * keymap and report corresponding event. Returns %true if lookup was 301 * successful and %false otherwise. 302 */ 303 bool sparse_keymap_report_event(struct input_dev *dev, unsigned int code, 304 unsigned int value, bool autorelease) 305 { 306 const struct key_entry *ke = 307 sparse_keymap_entry_from_scancode(dev, code); 308 309 if (ke) { 310 sparse_keymap_report_entry(dev, ke, value, autorelease); 311 return true; 312 } 313 314 return false; 315 } 316 EXPORT_SYMBOL(sparse_keymap_report_event); 317 318