1 /* ir-register.c - handle IR scancode->keycode tables
3 * Copyright (C) 2009 by Mauro Carvalho Chehab <mchehab@redhat.com>
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation version 2 of the License.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
16 #include <linux/input.h>
17 #include <linux/slab.h>
18 #include <media/ir-common.h>
20 /* Sizes are in bytes, 256 bytes allows for 32 entries on x64 */
21 #define IR_TAB_MIN_SIZE 256
22 #define IR_TAB_MAX_SIZE 8192
24 /* FIXME: IR_KEYPRESS_TIMEOUT should be protocol specific */
25 #define IR_KEYPRESS_TIMEOUT 250
28 * ir_resize_table() - resizes a scancode table if necessary
29 * @rc_tab: the ir_scancode_table to resize
30 * @return: zero on success or a negative error code
32 * This routine will shrink the ir_scancode_table if it has lots of
33 * unused entries and grow it if it is full.
35 static int ir_resize_table(struct ir_scancode_table *rc_tab)
37 unsigned int oldalloc = rc_tab->alloc;
38 unsigned int newalloc = oldalloc;
39 struct ir_scancode *oldscan = rc_tab->scan;
40 struct ir_scancode *newscan;
42 if (rc_tab->size == rc_tab->len) {
43 /* All entries in use -> grow keytable */
44 if (rc_tab->alloc >= IR_TAB_MAX_SIZE)
48 IR_dprintk(1, "Growing table to %u bytes\n", newalloc);
51 if ((rc_tab->len * 3 < rc_tab->size) && (oldalloc > IR_TAB_MIN_SIZE)) {
52 /* Less than 1/3 of entries in use -> shrink keytable */
54 IR_dprintk(1, "Shrinking table to %u bytes\n", newalloc);
57 if (newalloc == oldalloc)
60 newscan = kmalloc(newalloc, GFP_ATOMIC);
62 IR_dprintk(1, "Failed to kmalloc %u bytes\n", newalloc);
66 memcpy(newscan, rc_tab->scan, rc_tab->len * sizeof(struct ir_scancode));
67 rc_tab->scan = newscan;
68 rc_tab->alloc = newalloc;
69 rc_tab->size = rc_tab->alloc / sizeof(struct ir_scancode);
75 * ir_do_setkeycode() - internal function to set a keycode in the
76 * scancode->keycode table
77 * @dev: the struct input_dev device descriptor
78 * @rc_tab: the struct ir_scancode_table to set the keycode in
79 * @scancode: the scancode for the ir command
80 * @keycode: the keycode for the ir command
81 * @return: -EINVAL if the keycode could not be inserted, otherwise zero.
83 * This routine is used internally to manipulate the scancode->keycode table.
84 * The caller has to hold @rc_tab->lock.
86 static int ir_do_setkeycode(struct input_dev *dev,
87 struct ir_scancode_table *rc_tab,
88 unsigned scancode, unsigned keycode)
91 int old_keycode = KEY_RESERVED;
92 struct ir_input_dev *ir_dev = input_get_drvdata(dev);
95 * Unfortunately, some hardware-based IR decoders don't provide
96 * all bits for the complete IR code. In general, they provide only
97 * the command part of the IR code. Yet, as it is possible to replace
98 * the provided IR with another one, it is needed to allow loading
99 * IR tables from other remotes. So,
101 if (ir_dev->props && ir_dev->props->scanmask) {
102 scancode &= ir_dev->props->scanmask;
105 /* First check if we already have a mapping for this ir command */
106 for (i = 0; i < rc_tab->len; i++) {
107 /* Keytable is sorted from lowest to highest scancode */
108 if (rc_tab->scan[i].scancode > scancode)
110 else if (rc_tab->scan[i].scancode < scancode)
113 old_keycode = rc_tab->scan[i].keycode;
114 rc_tab->scan[i].keycode = keycode;
116 /* Did the user wish to remove the mapping? */
117 if (keycode == KEY_RESERVED || keycode == KEY_UNKNOWN) {
118 IR_dprintk(1, "#%d: Deleting scan 0x%04x\n",
121 memmove(&rc_tab->scan[i], &rc_tab->scan[i + 1],
122 (rc_tab->len - i) * sizeof(struct ir_scancode));
125 /* Possibly shrink the keytable, failure is not a problem */
126 ir_resize_table(rc_tab);
130 if (old_keycode == KEY_RESERVED) {
131 /* No previous mapping found, we might need to grow the table */
132 if (ir_resize_table(rc_tab))
135 IR_dprintk(1, "#%d: New scan 0x%04x with key 0x%04x\n",
136 i, scancode, keycode);
138 /* i is the proper index to insert our new keycode */
139 memmove(&rc_tab->scan[i + 1], &rc_tab->scan[i],
140 (rc_tab->len - i) * sizeof(struct ir_scancode));
141 rc_tab->scan[i].scancode = scancode;
142 rc_tab->scan[i].keycode = keycode;
144 set_bit(keycode, dev->keybit);
146 IR_dprintk(1, "#%d: Replacing scan 0x%04x with key 0x%04x\n",
147 i, scancode, keycode);
148 /* A previous mapping was updated... */
149 clear_bit(old_keycode, dev->keybit);
150 /* ...but another scancode might use the same keycode */
151 for (i = 0; i < rc_tab->len; i++) {
152 if (rc_tab->scan[i].keycode == old_keycode) {
153 set_bit(old_keycode, dev->keybit);
163 * ir_setkeycode() - set a keycode in the scancode->keycode table
164 * @dev: the struct input_dev device descriptor
165 * @scancode: the desired scancode
167 * @return: -EINVAL if the keycode could not be inserted, otherwise zero.
169 * This routine is used to handle evdev EVIOCSKEY ioctl.
171 static int ir_setkeycode(struct input_dev *dev,
172 unsigned int scancode, unsigned int keycode)
176 struct ir_input_dev *ir_dev = input_get_drvdata(dev);
177 struct ir_scancode_table *rc_tab = &ir_dev->rc_tab;
179 spin_lock_irqsave(&rc_tab->lock, flags);
180 rc = ir_do_setkeycode(dev, rc_tab, scancode, keycode);
181 spin_unlock_irqrestore(&rc_tab->lock, flags);
186 * ir_setkeytable() - sets several entries in the scancode->keycode table
187 * @dev: the struct input_dev device descriptor
188 * @to: the struct ir_scancode_table to copy entries to
189 * @from: the struct ir_scancode_table to copy entries from
190 * @return: -EINVAL if all keycodes could not be inserted, otherwise zero.
192 * This routine is used to handle table initialization.
194 static int ir_setkeytable(struct input_dev *dev,
195 struct ir_scancode_table *to,
196 const struct ir_scancode_table *from)
198 struct ir_input_dev *ir_dev = input_get_drvdata(dev);
199 struct ir_scancode_table *rc_tab = &ir_dev->rc_tab;
204 spin_lock_irqsave(&rc_tab->lock, flags);
205 for (i = 0; i < from->size; i++) {
206 rc = ir_do_setkeycode(dev, to, from->scan[i].scancode,
207 from->scan[i].keycode);
211 spin_unlock_irqrestore(&rc_tab->lock, flags);
216 * ir_getkeycode() - get a keycode from the scancode->keycode table
217 * @dev: the struct input_dev device descriptor
218 * @scancode: the desired scancode
219 * @keycode: used to return the keycode, if found, or KEY_RESERVED
220 * @return: always returns zero.
222 * This routine is used to handle evdev EVIOCGKEY ioctl.
224 static int ir_getkeycode(struct input_dev *dev,
225 unsigned int scancode, unsigned int *keycode)
229 int key = KEY_RESERVED;
230 struct ir_input_dev *ir_dev = input_get_drvdata(dev);
231 struct ir_scancode_table *rc_tab = &ir_dev->rc_tab;
233 spin_lock_irqsave(&rc_tab->lock, flags);
235 end = rc_tab->len - 1;
236 while (start <= end) {
237 mid = (start + end) / 2;
238 if (rc_tab->scan[mid].scancode < scancode)
240 else if (rc_tab->scan[mid].scancode > scancode)
243 key = rc_tab->scan[mid].keycode;
247 spin_unlock_irqrestore(&rc_tab->lock, flags);
249 if (key == KEY_RESERVED)
250 IR_dprintk(1, "unknown key for scancode 0x%04x\n",
258 * ir_g_keycode_from_table() - gets the keycode that corresponds to a scancode
259 * @input_dev: the struct input_dev descriptor of the device
260 * @scancode: the scancode that we're seeking
262 * This routine is used by the input routines when a key is pressed at the
263 * IR. The scancode is received and needs to be converted into a keycode.
264 * If the key is not found, it returns KEY_RESERVED. Otherwise, returns the
265 * corresponding keycode from the table.
267 u32 ir_g_keycode_from_table(struct input_dev *dev, u32 scancode)
271 ir_getkeycode(dev, scancode, &keycode);
272 if (keycode != KEY_RESERVED)
273 IR_dprintk(1, "%s: scancode 0x%04x keycode 0x%02x\n",
274 dev->name, scancode, keycode);
277 EXPORT_SYMBOL_GPL(ir_g_keycode_from_table);
280 * ir_keyup() - generates input event to cleanup a key press
281 * @ir: the struct ir_input_dev descriptor of the device
283 * This routine is used to signal that a key has been released on the
284 * remote control. It reports a keyup input event via input_report_key().
286 static void ir_keyup(struct ir_input_dev *ir)
291 IR_dprintk(1, "keyup key 0x%04x\n", ir->last_keycode);
292 input_report_key(ir->input_dev, ir->last_keycode, 0);
293 input_sync(ir->input_dev);
294 ir->keypressed = false;
298 * ir_timer_keyup() - generates a keyup event after a timeout
299 * @cookie: a pointer to struct ir_input_dev passed to setup_timer()
301 * This routine will generate a keyup event some time after a keydown event
302 * is generated when no further activity has been detected.
304 static void ir_timer_keyup(unsigned long cookie)
306 struct ir_input_dev *ir = (struct ir_input_dev *)cookie;
310 * ir->keyup_jiffies is used to prevent a race condition if a
311 * hardware interrupt occurs at this point and the keyup timer
312 * event is moved further into the future as a result.
314 * The timer will then be reactivated and this function called
315 * again in the future. We need to exit gracefully in that case
316 * to allow the input subsystem to do its auto-repeat magic or
317 * a keyup event might follow immediately after the keydown.
319 spin_lock_irqsave(&ir->keylock, flags);
320 if (time_is_after_eq_jiffies(ir->keyup_jiffies))
322 spin_unlock_irqrestore(&ir->keylock, flags);
326 * ir_repeat() - notifies the IR core that a key is still pressed
327 * @dev: the struct input_dev descriptor of the device
329 * This routine is used by IR decoders when a repeat message which does
330 * not include the necessary bits to reproduce the scancode has been
333 void ir_repeat(struct input_dev *dev)
336 struct ir_input_dev *ir = input_get_drvdata(dev);
338 spin_lock_irqsave(&ir->keylock, flags);
343 ir->keyup_jiffies = jiffies + msecs_to_jiffies(IR_KEYPRESS_TIMEOUT);
344 mod_timer(&ir->timer_keyup, ir->keyup_jiffies);
347 spin_unlock_irqrestore(&ir->keylock, flags);
349 EXPORT_SYMBOL_GPL(ir_repeat);
352 * ir_keydown() - generates input event for a key press
353 * @dev: the struct input_dev descriptor of the device
354 * @scancode: the scancode that we're seeking
355 * @toggle: the toggle value (protocol dependent, if the protocol doesn't
356 * support toggle values, this should be set to zero)
358 * This routine is used by the input routines when a key is pressed at the
359 * IR. It gets the keycode for a scancode and reports an input event via
360 * input_report_key().
362 void ir_keydown(struct input_dev *dev, int scancode, u8 toggle)
365 struct ir_input_dev *ir = input_get_drvdata(dev);
367 u32 keycode = ir_g_keycode_from_table(dev, scancode);
369 spin_lock_irqsave(&ir->keylock, flags);
372 if (ir->keypressed &&
373 ir->last_scancode == scancode &&
374 ir->last_toggle == toggle)
377 /* Release old keypress */
380 ir->last_scancode = scancode;
381 ir->last_toggle = toggle;
382 ir->last_keycode = keycode;
384 if (keycode == KEY_RESERVED)
387 /* Register a keypress */
388 ir->keypressed = true;
389 IR_dprintk(1, "%s: key down event, key 0x%04x, scancode 0x%04x\n",
390 dev->name, keycode, scancode);
391 input_report_key(dev, ir->last_keycode, 1);
395 ir->keyup_jiffies = jiffies + msecs_to_jiffies(IR_KEYPRESS_TIMEOUT);
396 mod_timer(&ir->timer_keyup, ir->keyup_jiffies);
398 spin_unlock_irqrestore(&ir->keylock, flags);
400 EXPORT_SYMBOL_GPL(ir_keydown);
402 static int ir_open(struct input_dev *input_dev)
404 struct ir_input_dev *ir_dev = input_get_drvdata(input_dev);
406 return ir_dev->props->open(ir_dev->props->priv);
409 static void ir_close(struct input_dev *input_dev)
411 struct ir_input_dev *ir_dev = input_get_drvdata(input_dev);
413 ir_dev->props->close(ir_dev->props->priv);
417 * __ir_input_register() - sets the IR keycode table and add the handlers
418 * for keymap table get/set
419 * @input_dev: the struct input_dev descriptor of the device
420 * @rc_tab: the struct ir_scancode_table table of scancode/keymap
422 * This routine is used to initialize the input infrastructure
423 * to work with an IR.
424 * It will register the input/evdev interface for the device and
425 * register the syfs code for IR class
427 int __ir_input_register(struct input_dev *input_dev,
428 const struct ir_scancode_table *rc_tab,
429 const struct ir_dev_props *props,
430 const char *driver_name)
432 struct ir_input_dev *ir_dev;
435 if (rc_tab->scan == NULL || !rc_tab->size)
438 ir_dev = kzalloc(sizeof(*ir_dev), GFP_KERNEL);
442 ir_dev->driver_name = kasprintf(GFP_KERNEL, "%s", driver_name);
443 if (!ir_dev->driver_name) {
448 input_dev->getkeycode = ir_getkeycode;
449 input_dev->setkeycode = ir_setkeycode;
450 input_set_drvdata(input_dev, ir_dev);
451 ir_dev->input_dev = input_dev;
453 spin_lock_init(&ir_dev->rc_tab.lock);
454 spin_lock_init(&ir_dev->keylock);
455 setup_timer(&ir_dev->timer_keyup, ir_timer_keyup, (unsigned long)ir_dev);
457 ir_dev->rc_tab.name = rc_tab->name;
458 ir_dev->rc_tab.ir_type = rc_tab->ir_type;
459 ir_dev->rc_tab.alloc = roundup_pow_of_two(rc_tab->size *
460 sizeof(struct ir_scancode));
461 ir_dev->rc_tab.scan = kmalloc(ir_dev->rc_tab.alloc, GFP_KERNEL);
462 ir_dev->rc_tab.size = ir_dev->rc_tab.alloc / sizeof(struct ir_scancode);
464 ir_dev->props = props;
466 input_dev->open = ir_open;
468 input_dev->close = ir_close;
471 if (!ir_dev->rc_tab.scan) {
476 IR_dprintk(1, "Allocated space for %u keycode entries (%u bytes)\n",
477 ir_dev->rc_tab.size, ir_dev->rc_tab.alloc);
479 set_bit(EV_KEY, input_dev->evbit);
480 set_bit(EV_REP, input_dev->evbit);
482 if (ir_setkeytable(input_dev, &ir_dev->rc_tab, rc_tab)) {
487 rc = ir_register_class(input_dev);
491 IR_dprintk(1, "Registered input device on %s for %s remote.\n",
492 driver_name, rc_tab->name);
497 kfree(ir_dev->rc_tab.scan);
499 kfree(ir_dev->driver_name);
504 EXPORT_SYMBOL_GPL(__ir_input_register);
507 * ir_input_unregister() - unregisters IR and frees resources
508 * @input_dev: the struct input_dev descriptor of the device
510 * This routine is used to free memory and de-register interfaces.
512 void ir_input_unregister(struct input_dev *dev)
514 struct ir_input_dev *ir_dev = input_get_drvdata(dev);
515 struct ir_scancode_table *rc_tab;
520 IR_dprintk(1, "Freed keycode table\n");
521 del_timer_sync(&ir_dev->timer_keyup);
522 rc_tab = &ir_dev->rc_tab;
527 ir_unregister_class(dev);
529 kfree(ir_dev->driver_name);
532 EXPORT_SYMBOL_GPL(ir_input_unregister);
534 int ir_core_debug; /* ir_debug level (0,1,2) */
535 EXPORT_SYMBOL_GPL(ir_core_debug);
536 module_param_named(debug, ir_core_debug, int, 0644);
538 MODULE_AUTHOR("Mauro Carvalho Chehab <mchehab@redhat.com>");
539 MODULE_LICENSE("GPL");