| 1 | /* rc-ir-raw.c - handle IR pulse/space events |
| 2 | * |
| 3 | * Copyright (C) 2010 by Mauro Carvalho Chehab |
| 4 | * |
| 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. |
| 8 | * |
| 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. |
| 13 | */ |
| 14 | |
| 15 | #include <linux/export.h> |
| 16 | #include <linux/kthread.h> |
| 17 | #include <linux/mutex.h> |
| 18 | #include <linux/kmod.h> |
| 19 | #include <linux/sched.h> |
| 20 | #include <linux/freezer.h> |
| 21 | #include "rc-core-priv.h" |
| 22 | |
| 23 | /* Define the max number of pulse/space transitions to buffer */ |
| 24 | #define MAX_IR_EVENT_SIZE 512 |
| 25 | |
| 26 | /* Used to keep track of IR raw clients, protected by ir_raw_handler_lock */ |
| 27 | static LIST_HEAD(ir_raw_client_list); |
| 28 | |
| 29 | /* Used to handle IR raw handler extensions */ |
| 30 | static DEFINE_MUTEX(ir_raw_handler_lock); |
| 31 | static LIST_HEAD(ir_raw_handler_list); |
| 32 | static u64 available_protocols; |
| 33 | static u64 encode_protocols; |
| 34 | |
| 35 | static int ir_raw_event_thread(void *data) |
| 36 | { |
| 37 | struct ir_raw_event ev; |
| 38 | struct ir_raw_handler *handler; |
| 39 | struct ir_raw_event_ctrl *raw = (struct ir_raw_event_ctrl *)data; |
| 40 | int retval; |
| 41 | |
| 42 | while (!kthread_should_stop()) { |
| 43 | |
| 44 | spin_lock_irq(&raw->lock); |
| 45 | retval = kfifo_len(&raw->kfifo); |
| 46 | |
| 47 | if (retval < sizeof(ev)) { |
| 48 | set_current_state(TASK_INTERRUPTIBLE); |
| 49 | |
| 50 | if (kthread_should_stop()) |
| 51 | set_current_state(TASK_RUNNING); |
| 52 | |
| 53 | spin_unlock_irq(&raw->lock); |
| 54 | schedule(); |
| 55 | continue; |
| 56 | } |
| 57 | |
| 58 | retval = kfifo_out(&raw->kfifo, &ev, sizeof(ev)); |
| 59 | spin_unlock_irq(&raw->lock); |
| 60 | |
| 61 | mutex_lock(&ir_raw_handler_lock); |
| 62 | list_for_each_entry(handler, &ir_raw_handler_list, list) |
| 63 | handler->decode(raw->dev, ev); |
| 64 | raw->prev_ev = ev; |
| 65 | mutex_unlock(&ir_raw_handler_lock); |
| 66 | } |
| 67 | |
| 68 | return 0; |
| 69 | } |
| 70 | |
| 71 | /** |
| 72 | * ir_raw_event_store() - pass a pulse/space duration to the raw ir decoders |
| 73 | * @dev: the struct rc_dev device descriptor |
| 74 | * @ev: the struct ir_raw_event descriptor of the pulse/space |
| 75 | * |
| 76 | * This routine (which may be called from an interrupt context) stores a |
| 77 | * pulse/space duration for the raw ir decoding state machines. Pulses are |
| 78 | * signalled as positive values and spaces as negative values. A zero value |
| 79 | * will reset the decoding state machines. |
| 80 | */ |
| 81 | int ir_raw_event_store(struct rc_dev *dev, struct ir_raw_event *ev) |
| 82 | { |
| 83 | if (!dev->raw) |
| 84 | return -EINVAL; |
| 85 | |
| 86 | IR_dprintk(2, "sample: (%05dus %s)\n", |
| 87 | TO_US(ev->duration), TO_STR(ev->pulse)); |
| 88 | |
| 89 | if (kfifo_in(&dev->raw->kfifo, ev, sizeof(*ev)) != sizeof(*ev)) |
| 90 | return -ENOMEM; |
| 91 | |
| 92 | return 0; |
| 93 | } |
| 94 | EXPORT_SYMBOL_GPL(ir_raw_event_store); |
| 95 | |
| 96 | /** |
| 97 | * ir_raw_event_store_edge() - notify raw ir decoders of the start of a pulse/space |
| 98 | * @dev: the struct rc_dev device descriptor |
| 99 | * @type: the type of the event that has occurred |
| 100 | * |
| 101 | * This routine (which may be called from an interrupt context) is used to |
| 102 | * store the beginning of an ir pulse or space (or the start/end of ir |
| 103 | * reception) for the raw ir decoding state machines. This is used by |
| 104 | * hardware which does not provide durations directly but only interrupts |
| 105 | * (or similar events) on state change. |
| 106 | */ |
| 107 | int ir_raw_event_store_edge(struct rc_dev *dev, enum raw_event_type type) |
| 108 | { |
| 109 | ktime_t now; |
| 110 | s64 delta; /* ns */ |
| 111 | DEFINE_IR_RAW_EVENT(ev); |
| 112 | int rc = 0; |
| 113 | int delay; |
| 114 | |
| 115 | if (!dev->raw) |
| 116 | return -EINVAL; |
| 117 | |
| 118 | now = ktime_get(); |
| 119 | delta = ktime_to_ns(ktime_sub(now, dev->raw->last_event)); |
| 120 | delay = MS_TO_NS(dev->input_dev->rep[REP_DELAY]); |
| 121 | |
| 122 | /* Check for a long duration since last event or if we're |
| 123 | * being called for the first time, note that delta can't |
| 124 | * possibly be negative. |
| 125 | */ |
| 126 | if (delta > delay || !dev->raw->last_type) |
| 127 | type |= IR_START_EVENT; |
| 128 | else |
| 129 | ev.duration = delta; |
| 130 | |
| 131 | if (type & IR_START_EVENT) |
| 132 | ir_raw_event_reset(dev); |
| 133 | else if (dev->raw->last_type & IR_SPACE) { |
| 134 | ev.pulse = false; |
| 135 | rc = ir_raw_event_store(dev, &ev); |
| 136 | } else if (dev->raw->last_type & IR_PULSE) { |
| 137 | ev.pulse = true; |
| 138 | rc = ir_raw_event_store(dev, &ev); |
| 139 | } else |
| 140 | return 0; |
| 141 | |
| 142 | dev->raw->last_event = now; |
| 143 | dev->raw->last_type = type; |
| 144 | return rc; |
| 145 | } |
| 146 | EXPORT_SYMBOL_GPL(ir_raw_event_store_edge); |
| 147 | |
| 148 | /** |
| 149 | * ir_raw_event_store_with_filter() - pass next pulse/space to decoders with some processing |
| 150 | * @dev: the struct rc_dev device descriptor |
| 151 | * @type: the type of the event that has occurred |
| 152 | * |
| 153 | * This routine (which may be called from an interrupt context) works |
| 154 | * in similar manner to ir_raw_event_store_edge. |
| 155 | * This routine is intended for devices with limited internal buffer |
| 156 | * It automerges samples of same type, and handles timeouts. Returns non-zero |
| 157 | * if the event was added, and zero if the event was ignored due to idle |
| 158 | * processing. |
| 159 | */ |
| 160 | int ir_raw_event_store_with_filter(struct rc_dev *dev, struct ir_raw_event *ev) |
| 161 | { |
| 162 | if (!dev->raw) |
| 163 | return -EINVAL; |
| 164 | |
| 165 | /* Ignore spaces in idle mode */ |
| 166 | if (dev->idle && !ev->pulse) |
| 167 | return 0; |
| 168 | else if (dev->idle) |
| 169 | ir_raw_event_set_idle(dev, false); |
| 170 | |
| 171 | if (!dev->raw->this_ev.duration) |
| 172 | dev->raw->this_ev = *ev; |
| 173 | else if (ev->pulse == dev->raw->this_ev.pulse) |
| 174 | dev->raw->this_ev.duration += ev->duration; |
| 175 | else { |
| 176 | ir_raw_event_store(dev, &dev->raw->this_ev); |
| 177 | dev->raw->this_ev = *ev; |
| 178 | } |
| 179 | |
| 180 | /* Enter idle mode if nessesary */ |
| 181 | if (!ev->pulse && dev->timeout && |
| 182 | dev->raw->this_ev.duration >= dev->timeout) |
| 183 | ir_raw_event_set_idle(dev, true); |
| 184 | |
| 185 | return 1; |
| 186 | } |
| 187 | EXPORT_SYMBOL_GPL(ir_raw_event_store_with_filter); |
| 188 | |
| 189 | /** |
| 190 | * ir_raw_event_set_idle() - provide hint to rc-core when the device is idle or not |
| 191 | * @dev: the struct rc_dev device descriptor |
| 192 | * @idle: whether the device is idle or not |
| 193 | */ |
| 194 | void ir_raw_event_set_idle(struct rc_dev *dev, bool idle) |
| 195 | { |
| 196 | if (!dev->raw) |
| 197 | return; |
| 198 | |
| 199 | IR_dprintk(2, "%s idle mode\n", idle ? "enter" : "leave"); |
| 200 | |
| 201 | if (idle) { |
| 202 | dev->raw->this_ev.timeout = true; |
| 203 | ir_raw_event_store(dev, &dev->raw->this_ev); |
| 204 | init_ir_raw_event(&dev->raw->this_ev); |
| 205 | } |
| 206 | |
| 207 | if (dev->s_idle) |
| 208 | dev->s_idle(dev, idle); |
| 209 | |
| 210 | dev->idle = idle; |
| 211 | } |
| 212 | EXPORT_SYMBOL_GPL(ir_raw_event_set_idle); |
| 213 | |
| 214 | /** |
| 215 | * ir_raw_event_handle() - schedules the decoding of stored ir data |
| 216 | * @dev: the struct rc_dev device descriptor |
| 217 | * |
| 218 | * This routine will tell rc-core to start decoding stored ir data. |
| 219 | */ |
| 220 | void ir_raw_event_handle(struct rc_dev *dev) |
| 221 | { |
| 222 | unsigned long flags; |
| 223 | |
| 224 | if (!dev->raw) |
| 225 | return; |
| 226 | |
| 227 | spin_lock_irqsave(&dev->raw->lock, flags); |
| 228 | wake_up_process(dev->raw->thread); |
| 229 | spin_unlock_irqrestore(&dev->raw->lock, flags); |
| 230 | } |
| 231 | EXPORT_SYMBOL_GPL(ir_raw_event_handle); |
| 232 | |
| 233 | /* used internally by the sysfs interface */ |
| 234 | u64 |
| 235 | ir_raw_get_allowed_protocols(void) |
| 236 | { |
| 237 | u64 protocols; |
| 238 | mutex_lock(&ir_raw_handler_lock); |
| 239 | protocols = available_protocols; |
| 240 | mutex_unlock(&ir_raw_handler_lock); |
| 241 | return protocols; |
| 242 | } |
| 243 | |
| 244 | /* used internally by the sysfs interface */ |
| 245 | u64 |
| 246 | ir_raw_get_encode_protocols(void) |
| 247 | { |
| 248 | u64 protocols; |
| 249 | |
| 250 | mutex_lock(&ir_raw_handler_lock); |
| 251 | protocols = encode_protocols; |
| 252 | mutex_unlock(&ir_raw_handler_lock); |
| 253 | return protocols; |
| 254 | } |
| 255 | |
| 256 | static int change_protocol(struct rc_dev *dev, u64 *rc_type) |
| 257 | { |
| 258 | /* the caller will update dev->enabled_protocols */ |
| 259 | return 0; |
| 260 | } |
| 261 | |
| 262 | /** |
| 263 | * ir_raw_gen_manchester() - Encode data with Manchester (bi-phase) modulation. |
| 264 | * @ev: Pointer to pointer to next free event. *@ev is incremented for |
| 265 | * each raw event filled. |
| 266 | * @max: Maximum number of raw events to fill. |
| 267 | * @timings: Manchester modulation timings. |
| 268 | * @n: Number of bits of data. |
| 269 | * @data: Data bits to encode. |
| 270 | * |
| 271 | * Encodes the @n least significant bits of @data using Manchester (bi-phase) |
| 272 | * modulation with the timing characteristics described by @timings, writing up |
| 273 | * to @max raw IR events using the *@ev pointer. |
| 274 | * |
| 275 | * Returns: 0 on success. |
| 276 | * -ENOBUFS if there isn't enough space in the array to fit the |
| 277 | * full encoded data. In this case all @max events will have been |
| 278 | * written. |
| 279 | */ |
| 280 | int ir_raw_gen_manchester(struct ir_raw_event **ev, unsigned int max, |
| 281 | const struct ir_raw_timings_manchester *timings, |
| 282 | unsigned int n, unsigned int data) |
| 283 | { |
| 284 | bool need_pulse; |
| 285 | unsigned int i; |
| 286 | int ret = -ENOBUFS; |
| 287 | |
| 288 | i = 1 << (n - 1); |
| 289 | |
| 290 | if (timings->leader) { |
| 291 | if (!max--) |
| 292 | return ret; |
| 293 | if (timings->pulse_space_start) { |
| 294 | init_ir_raw_event_duration((*ev)++, 1, timings->leader); |
| 295 | |
| 296 | if (!max--) |
| 297 | return ret; |
| 298 | init_ir_raw_event_duration((*ev), 0, timings->leader); |
| 299 | } else { |
| 300 | init_ir_raw_event_duration((*ev), 1, timings->leader); |
| 301 | } |
| 302 | i >>= 1; |
| 303 | } else { |
| 304 | /* continue existing signal */ |
| 305 | --(*ev); |
| 306 | } |
| 307 | /* from here on *ev will point to the last event rather than the next */ |
| 308 | |
| 309 | while (n && i > 0) { |
| 310 | need_pulse = !(data & i); |
| 311 | if (timings->invert) |
| 312 | need_pulse = !need_pulse; |
| 313 | if (need_pulse == !!(*ev)->pulse) { |
| 314 | (*ev)->duration += timings->clock; |
| 315 | } else { |
| 316 | if (!max--) |
| 317 | goto nobufs; |
| 318 | init_ir_raw_event_duration(++(*ev), need_pulse, |
| 319 | timings->clock); |
| 320 | } |
| 321 | |
| 322 | if (!max--) |
| 323 | goto nobufs; |
| 324 | init_ir_raw_event_duration(++(*ev), !need_pulse, |
| 325 | timings->clock); |
| 326 | i >>= 1; |
| 327 | } |
| 328 | |
| 329 | if (timings->trailer_space) { |
| 330 | if (!(*ev)->pulse) |
| 331 | (*ev)->duration += timings->trailer_space; |
| 332 | else if (!max--) |
| 333 | goto nobufs; |
| 334 | else |
| 335 | init_ir_raw_event_duration(++(*ev), 0, |
| 336 | timings->trailer_space); |
| 337 | } |
| 338 | |
| 339 | ret = 0; |
| 340 | nobufs: |
| 341 | /* point to the next event rather than last event before returning */ |
| 342 | ++(*ev); |
| 343 | return ret; |
| 344 | } |
| 345 | EXPORT_SYMBOL(ir_raw_gen_manchester); |
| 346 | |
| 347 | /** |
| 348 | * ir_raw_encode_scancode() - Encode a scancode as raw events |
| 349 | * |
| 350 | * @protocols: permitted protocols |
| 351 | * @scancode: scancode filter describing a single scancode |
| 352 | * @events: array of raw events to write into |
| 353 | * @max: max number of raw events |
| 354 | * |
| 355 | * Attempts to encode the scancode as raw events. |
| 356 | * |
| 357 | * Returns: The number of events written. |
| 358 | * -ENOBUFS if there isn't enough space in the array to fit the |
| 359 | * encoding. In this case all @max events will have been written. |
| 360 | * -EINVAL if the scancode is ambiguous or invalid, or if no |
| 361 | * compatible encoder was found. |
| 362 | */ |
| 363 | int ir_raw_encode_scancode(u64 protocols, |
| 364 | const struct rc_scancode_filter *scancode, |
| 365 | struct ir_raw_event *events, unsigned int max) |
| 366 | { |
| 367 | struct ir_raw_handler *handler; |
| 368 | int ret = -EINVAL; |
| 369 | |
| 370 | mutex_lock(&ir_raw_handler_lock); |
| 371 | list_for_each_entry(handler, &ir_raw_handler_list, list) { |
| 372 | if (handler->protocols & protocols && handler->encode) { |
| 373 | ret = handler->encode(protocols, scancode, events, max); |
| 374 | if (ret >= 0 || ret == -ENOBUFS) |
| 375 | break; |
| 376 | } |
| 377 | } |
| 378 | mutex_unlock(&ir_raw_handler_lock); |
| 379 | |
| 380 | return ret; |
| 381 | } |
| 382 | EXPORT_SYMBOL(ir_raw_encode_scancode); |
| 383 | |
| 384 | /* |
| 385 | * Used to (un)register raw event clients |
| 386 | */ |
| 387 | int ir_raw_event_register(struct rc_dev *dev) |
| 388 | { |
| 389 | int rc; |
| 390 | struct ir_raw_handler *handler; |
| 391 | |
| 392 | if (!dev) |
| 393 | return -EINVAL; |
| 394 | |
| 395 | dev->raw = kzalloc(sizeof(*dev->raw), GFP_KERNEL); |
| 396 | if (!dev->raw) |
| 397 | return -ENOMEM; |
| 398 | |
| 399 | dev->raw->dev = dev; |
| 400 | dev->change_protocol = change_protocol; |
| 401 | rc = kfifo_alloc(&dev->raw->kfifo, |
| 402 | sizeof(struct ir_raw_event) * MAX_IR_EVENT_SIZE, |
| 403 | GFP_KERNEL); |
| 404 | if (rc < 0) |
| 405 | goto out; |
| 406 | |
| 407 | spin_lock_init(&dev->raw->lock); |
| 408 | dev->raw->thread = kthread_run(ir_raw_event_thread, dev->raw, |
| 409 | "rc%ld", dev->devno); |
| 410 | |
| 411 | if (IS_ERR(dev->raw->thread)) { |
| 412 | rc = PTR_ERR(dev->raw->thread); |
| 413 | goto out; |
| 414 | } |
| 415 | |
| 416 | mutex_lock(&ir_raw_handler_lock); |
| 417 | list_add_tail(&dev->raw->list, &ir_raw_client_list); |
| 418 | list_for_each_entry(handler, &ir_raw_handler_list, list) |
| 419 | if (handler->raw_register) |
| 420 | handler->raw_register(dev); |
| 421 | mutex_unlock(&ir_raw_handler_lock); |
| 422 | |
| 423 | return 0; |
| 424 | |
| 425 | out: |
| 426 | kfree(dev->raw); |
| 427 | dev->raw = NULL; |
| 428 | return rc; |
| 429 | } |
| 430 | |
| 431 | void ir_raw_event_unregister(struct rc_dev *dev) |
| 432 | { |
| 433 | struct ir_raw_handler *handler; |
| 434 | |
| 435 | if (!dev || !dev->raw) |
| 436 | return; |
| 437 | |
| 438 | kthread_stop(dev->raw->thread); |
| 439 | |
| 440 | mutex_lock(&ir_raw_handler_lock); |
| 441 | list_del(&dev->raw->list); |
| 442 | list_for_each_entry(handler, &ir_raw_handler_list, list) |
| 443 | if (handler->raw_unregister) |
| 444 | handler->raw_unregister(dev); |
| 445 | mutex_unlock(&ir_raw_handler_lock); |
| 446 | |
| 447 | kfifo_free(&dev->raw->kfifo); |
| 448 | kfree(dev->raw); |
| 449 | dev->raw = NULL; |
| 450 | } |
| 451 | |
| 452 | /* |
| 453 | * Extension interface - used to register the IR decoders |
| 454 | */ |
| 455 | |
| 456 | int ir_raw_handler_register(struct ir_raw_handler *ir_raw_handler) |
| 457 | { |
| 458 | struct ir_raw_event_ctrl *raw; |
| 459 | |
| 460 | mutex_lock(&ir_raw_handler_lock); |
| 461 | list_add_tail(&ir_raw_handler->list, &ir_raw_handler_list); |
| 462 | if (ir_raw_handler->raw_register) |
| 463 | list_for_each_entry(raw, &ir_raw_client_list, list) |
| 464 | ir_raw_handler->raw_register(raw->dev); |
| 465 | available_protocols |= ir_raw_handler->protocols; |
| 466 | if (ir_raw_handler->encode) |
| 467 | encode_protocols |= ir_raw_handler->protocols; |
| 468 | mutex_unlock(&ir_raw_handler_lock); |
| 469 | |
| 470 | return 0; |
| 471 | } |
| 472 | EXPORT_SYMBOL(ir_raw_handler_register); |
| 473 | |
| 474 | void ir_raw_handler_unregister(struct ir_raw_handler *ir_raw_handler) |
| 475 | { |
| 476 | struct ir_raw_event_ctrl *raw; |
| 477 | |
| 478 | mutex_lock(&ir_raw_handler_lock); |
| 479 | list_del(&ir_raw_handler->list); |
| 480 | if (ir_raw_handler->raw_unregister) |
| 481 | list_for_each_entry(raw, &ir_raw_client_list, list) |
| 482 | ir_raw_handler->raw_unregister(raw->dev); |
| 483 | available_protocols &= ~ir_raw_handler->protocols; |
| 484 | if (ir_raw_handler->encode) |
| 485 | encode_protocols &= ~ir_raw_handler->protocols; |
| 486 | mutex_unlock(&ir_raw_handler_lock); |
| 487 | } |
| 488 | EXPORT_SYMBOL(ir_raw_handler_unregister); |
| 489 | |
| 490 | void ir_raw_init(void) |
| 491 | { |
| 492 | /* Load the decoder modules */ |
| 493 | |
| 494 | load_nec_decode(); |
| 495 | load_rc5_decode(); |
| 496 | load_rc6_decode(); |
| 497 | load_jvc_decode(); |
| 498 | load_sony_decode(); |
| 499 | load_sanyo_decode(); |
| 500 | load_sharp_decode(); |
| 501 | load_mce_kbd_decode(); |
| 502 | load_lirc_codec(); |
| 503 | load_xmp_decode(); |
| 504 | |
| 505 | /* If needed, we may later add some init code. In this case, |
| 506 | it is needed to change the CONFIG_MODULE test at rc-core.h |
| 507 | */ |
| 508 | } |