1 /* 2 * ALSA sequencer Timer 3 * Copyright (c) 1998-1999 by Frank van de Pol <fvdpol@coil.demon.nl> 4 * Jaroslav Kysela <perex@perex.cz> 5 * 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License as published by 9 * the Free Software Foundation; either version 2 of the License, or 10 * (at your option) any later version. 11 * 12 * This program is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 * GNU General Public License for more details. 16 * 17 * You should have received a copy of the GNU General Public License 18 * along with this program; if not, write to the Free Software 19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 20 * 21 */ 22 23 #include <sound/core.h> 24 #include <linux/slab.h> 25 #include "seq_timer.h" 26 #include "seq_queue.h" 27 #include "seq_info.h" 28 29 /* allowed sequencer timer frequencies, in Hz */ 30 #define MIN_FREQUENCY 10 31 #define MAX_FREQUENCY 6250 32 #define DEFAULT_FREQUENCY 1000 33 34 #define SKEW_BASE 0x10000 /* 16bit shift */ 35 36 static void snd_seq_timer_set_tick_resolution(struct snd_seq_timer *tmr) 37 { 38 if (tmr->tempo < 1000000) 39 tmr->tick.resolution = (tmr->tempo * 1000) / tmr->ppq; 40 else { 41 /* might overflow.. */ 42 unsigned int s; 43 s = tmr->tempo % tmr->ppq; 44 s = (s * 1000) / tmr->ppq; 45 tmr->tick.resolution = (tmr->tempo / tmr->ppq) * 1000; 46 tmr->tick.resolution += s; 47 } 48 if (tmr->tick.resolution <= 0) 49 tmr->tick.resolution = 1; 50 snd_seq_timer_update_tick(&tmr->tick, 0); 51 } 52 53 /* create new timer (constructor) */ 54 struct snd_seq_timer *snd_seq_timer_new(void) 55 { 56 struct snd_seq_timer *tmr; 57 58 tmr = kzalloc(sizeof(*tmr), GFP_KERNEL); 59 if (!tmr) 60 return NULL; 61 spin_lock_init(&tmr->lock); 62 63 /* reset setup to defaults */ 64 snd_seq_timer_defaults(tmr); 65 66 /* reset time */ 67 snd_seq_timer_reset(tmr); 68 69 return tmr; 70 } 71 72 /* delete timer (destructor) */ 73 void snd_seq_timer_delete(struct snd_seq_timer **tmr) 74 { 75 struct snd_seq_timer *t = *tmr; 76 *tmr = NULL; 77 78 if (t == NULL) { 79 pr_debug("ALSA: seq: snd_seq_timer_delete() called with NULL timer\n"); 80 return; 81 } 82 t->running = 0; 83 84 /* reset time */ 85 snd_seq_timer_stop(t); 86 snd_seq_timer_reset(t); 87 88 kfree(t); 89 } 90 91 void snd_seq_timer_defaults(struct snd_seq_timer * tmr) 92 { 93 unsigned long flags; 94 95 spin_lock_irqsave(&tmr->lock, flags); 96 /* setup defaults */ 97 tmr->ppq = 96; /* 96 PPQ */ 98 tmr->tempo = 500000; /* 120 BPM */ 99 snd_seq_timer_set_tick_resolution(tmr); 100 tmr->running = 0; 101 102 tmr->type = SNDRV_SEQ_TIMER_ALSA; 103 tmr->alsa_id.dev_class = seq_default_timer_class; 104 tmr->alsa_id.dev_sclass = seq_default_timer_sclass; 105 tmr->alsa_id.card = seq_default_timer_card; 106 tmr->alsa_id.device = seq_default_timer_device; 107 tmr->alsa_id.subdevice = seq_default_timer_subdevice; 108 tmr->preferred_resolution = seq_default_timer_resolution; 109 110 tmr->skew = tmr->skew_base = SKEW_BASE; 111 spin_unlock_irqrestore(&tmr->lock, flags); 112 } 113 114 static void seq_timer_reset(struct snd_seq_timer *tmr) 115 { 116 /* reset time & songposition */ 117 tmr->cur_time.tv_sec = 0; 118 tmr->cur_time.tv_nsec = 0; 119 120 tmr->tick.cur_tick = 0; 121 tmr->tick.fraction = 0; 122 } 123 124 void snd_seq_timer_reset(struct snd_seq_timer *tmr) 125 { 126 unsigned long flags; 127 128 spin_lock_irqsave(&tmr->lock, flags); 129 seq_timer_reset(tmr); 130 spin_unlock_irqrestore(&tmr->lock, flags); 131 } 132 133 134 /* called by timer interrupt routine. the period time since previous invocation is passed */ 135 static void snd_seq_timer_interrupt(struct snd_timer_instance *timeri, 136 unsigned long resolution, 137 unsigned long ticks) 138 { 139 unsigned long flags; 140 struct snd_seq_queue *q = timeri->callback_data; 141 struct snd_seq_timer *tmr; 142 143 if (q == NULL) 144 return; 145 tmr = q->timer; 146 if (tmr == NULL) 147 return; 148 spin_lock_irqsave(&tmr->lock, flags); 149 if (!tmr->running) { 150 spin_unlock_irqrestore(&tmr->lock, flags); 151 return; 152 } 153 154 resolution *= ticks; 155 if (tmr->skew != tmr->skew_base) { 156 /* FIXME: assuming skew_base = 0x10000 */ 157 resolution = (resolution >> 16) * tmr->skew + 158 (((resolution & 0xffff) * tmr->skew) >> 16); 159 } 160 161 /* update timer */ 162 snd_seq_inc_time_nsec(&tmr->cur_time, resolution); 163 164 /* calculate current tick */ 165 snd_seq_timer_update_tick(&tmr->tick, resolution); 166 167 /* register actual time of this timer update */ 168 ktime_get_ts64(&tmr->last_update); 169 170 spin_unlock_irqrestore(&tmr->lock, flags); 171 172 /* check queues and dispatch events */ 173 snd_seq_check_queue(q, 1, 0); 174 } 175 176 /* set current tempo */ 177 int snd_seq_timer_set_tempo(struct snd_seq_timer * tmr, int tempo) 178 { 179 unsigned long flags; 180 181 if (snd_BUG_ON(!tmr)) 182 return -EINVAL; 183 if (tempo <= 0) 184 return -EINVAL; 185 spin_lock_irqsave(&tmr->lock, flags); 186 if ((unsigned int)tempo != tmr->tempo) { 187 tmr->tempo = tempo; 188 snd_seq_timer_set_tick_resolution(tmr); 189 } 190 spin_unlock_irqrestore(&tmr->lock, flags); 191 return 0; 192 } 193 194 /* set current tempo and ppq in a shot */ 195 int snd_seq_timer_set_tempo_ppq(struct snd_seq_timer *tmr, int tempo, int ppq) 196 { 197 int changed; 198 unsigned long flags; 199 200 if (snd_BUG_ON(!tmr)) 201 return -EINVAL; 202 if (tempo <= 0 || ppq <= 0) 203 return -EINVAL; 204 spin_lock_irqsave(&tmr->lock, flags); 205 if (tmr->running && (ppq != tmr->ppq)) { 206 /* refuse to change ppq on running timers */ 207 /* because it will upset the song position (ticks) */ 208 spin_unlock_irqrestore(&tmr->lock, flags); 209 pr_debug("ALSA: seq: cannot change ppq of a running timer\n"); 210 return -EBUSY; 211 } 212 changed = (tempo != tmr->tempo) || (ppq != tmr->ppq); 213 tmr->tempo = tempo; 214 tmr->ppq = ppq; 215 if (changed) 216 snd_seq_timer_set_tick_resolution(tmr); 217 spin_unlock_irqrestore(&tmr->lock, flags); 218 return 0; 219 } 220 221 /* set current tick position */ 222 int snd_seq_timer_set_position_tick(struct snd_seq_timer *tmr, 223 snd_seq_tick_time_t position) 224 { 225 unsigned long flags; 226 227 if (snd_BUG_ON(!tmr)) 228 return -EINVAL; 229 230 spin_lock_irqsave(&tmr->lock, flags); 231 tmr->tick.cur_tick = position; 232 tmr->tick.fraction = 0; 233 spin_unlock_irqrestore(&tmr->lock, flags); 234 return 0; 235 } 236 237 /* set current real-time position */ 238 int snd_seq_timer_set_position_time(struct snd_seq_timer *tmr, 239 snd_seq_real_time_t position) 240 { 241 unsigned long flags; 242 243 if (snd_BUG_ON(!tmr)) 244 return -EINVAL; 245 246 snd_seq_sanity_real_time(&position); 247 spin_lock_irqsave(&tmr->lock, flags); 248 tmr->cur_time = position; 249 spin_unlock_irqrestore(&tmr->lock, flags); 250 return 0; 251 } 252 253 /* set timer skew */ 254 int snd_seq_timer_set_skew(struct snd_seq_timer *tmr, unsigned int skew, 255 unsigned int base) 256 { 257 unsigned long flags; 258 259 if (snd_BUG_ON(!tmr)) 260 return -EINVAL; 261 262 /* FIXME */ 263 if (base != SKEW_BASE) { 264 pr_debug("ALSA: seq: invalid skew base 0x%x\n", base); 265 return -EINVAL; 266 } 267 spin_lock_irqsave(&tmr->lock, flags); 268 tmr->skew = skew; 269 spin_unlock_irqrestore(&tmr->lock, flags); 270 return 0; 271 } 272 273 int snd_seq_timer_open(struct snd_seq_queue *q) 274 { 275 struct snd_timer_instance *t; 276 struct snd_seq_timer *tmr; 277 char str[32]; 278 int err; 279 280 tmr = q->timer; 281 if (snd_BUG_ON(!tmr)) 282 return -EINVAL; 283 if (tmr->timeri) 284 return -EBUSY; 285 sprintf(str, "sequencer queue %i", q->queue); 286 if (tmr->type != SNDRV_SEQ_TIMER_ALSA) /* standard ALSA timer */ 287 return -EINVAL; 288 if (tmr->alsa_id.dev_class != SNDRV_TIMER_CLASS_SLAVE) 289 tmr->alsa_id.dev_sclass = SNDRV_TIMER_SCLASS_SEQUENCER; 290 err = snd_timer_open(&t, str, &tmr->alsa_id, q->queue); 291 if (err < 0 && tmr->alsa_id.dev_class != SNDRV_TIMER_CLASS_SLAVE) { 292 if (tmr->alsa_id.dev_class != SNDRV_TIMER_CLASS_GLOBAL || 293 tmr->alsa_id.device != SNDRV_TIMER_GLOBAL_SYSTEM) { 294 struct snd_timer_id tid; 295 memset(&tid, 0, sizeof(tid)); 296 tid.dev_class = SNDRV_TIMER_CLASS_GLOBAL; 297 tid.dev_sclass = SNDRV_TIMER_SCLASS_SEQUENCER; 298 tid.card = -1; 299 tid.device = SNDRV_TIMER_GLOBAL_SYSTEM; 300 err = snd_timer_open(&t, str, &tid, q->queue); 301 } 302 } 303 if (err < 0) { 304 pr_err("ALSA: seq fatal error: cannot create timer (%i)\n", err); 305 return err; 306 } 307 t->callback = snd_seq_timer_interrupt; 308 t->callback_data = q; 309 t->flags |= SNDRV_TIMER_IFLG_AUTO; 310 spin_lock_irq(&tmr->lock); 311 tmr->timeri = t; 312 spin_unlock_irq(&tmr->lock); 313 return 0; 314 } 315 316 int snd_seq_timer_close(struct snd_seq_queue *q) 317 { 318 struct snd_seq_timer *tmr; 319 struct snd_timer_instance *t; 320 321 tmr = q->timer; 322 if (snd_BUG_ON(!tmr)) 323 return -EINVAL; 324 spin_lock_irq(&tmr->lock); 325 t = tmr->timeri; 326 tmr->timeri = NULL; 327 spin_unlock_irq(&tmr->lock); 328 if (t) 329 snd_timer_close(t); 330 return 0; 331 } 332 333 static int seq_timer_stop(struct snd_seq_timer *tmr) 334 { 335 if (! tmr->timeri) 336 return -EINVAL; 337 if (!tmr->running) 338 return 0; 339 tmr->running = 0; 340 snd_timer_pause(tmr->timeri); 341 return 0; 342 } 343 344 int snd_seq_timer_stop(struct snd_seq_timer *tmr) 345 { 346 unsigned long flags; 347 int err; 348 349 spin_lock_irqsave(&tmr->lock, flags); 350 err = seq_timer_stop(tmr); 351 spin_unlock_irqrestore(&tmr->lock, flags); 352 return err; 353 } 354 355 static int initialize_timer(struct snd_seq_timer *tmr) 356 { 357 struct snd_timer *t; 358 unsigned long freq; 359 360 t = tmr->timeri->timer; 361 if (!t) 362 return -EINVAL; 363 364 freq = tmr->preferred_resolution; 365 if (!freq) 366 freq = DEFAULT_FREQUENCY; 367 else if (freq < MIN_FREQUENCY) 368 freq = MIN_FREQUENCY; 369 else if (freq > MAX_FREQUENCY) 370 freq = MAX_FREQUENCY; 371 372 tmr->ticks = 1; 373 if (!(t->hw.flags & SNDRV_TIMER_HW_SLAVE)) { 374 unsigned long r = snd_timer_resolution(tmr->timeri); 375 if (r) { 376 tmr->ticks = (unsigned int)(1000000000uL / (r * freq)); 377 if (! tmr->ticks) 378 tmr->ticks = 1; 379 } 380 } 381 tmr->initialized = 1; 382 return 0; 383 } 384 385 static int seq_timer_start(struct snd_seq_timer *tmr) 386 { 387 if (! tmr->timeri) 388 return -EINVAL; 389 if (tmr->running) 390 seq_timer_stop(tmr); 391 seq_timer_reset(tmr); 392 if (initialize_timer(tmr) < 0) 393 return -EINVAL; 394 snd_timer_start(tmr->timeri, tmr->ticks); 395 tmr->running = 1; 396 ktime_get_ts64(&tmr->last_update); 397 return 0; 398 } 399 400 int snd_seq_timer_start(struct snd_seq_timer *tmr) 401 { 402 unsigned long flags; 403 int err; 404 405 spin_lock_irqsave(&tmr->lock, flags); 406 err = seq_timer_start(tmr); 407 spin_unlock_irqrestore(&tmr->lock, flags); 408 return err; 409 } 410 411 static int seq_timer_continue(struct snd_seq_timer *tmr) 412 { 413 if (! tmr->timeri) 414 return -EINVAL; 415 if (tmr->running) 416 return -EBUSY; 417 if (! tmr->initialized) { 418 seq_timer_reset(tmr); 419 if (initialize_timer(tmr) < 0) 420 return -EINVAL; 421 } 422 snd_timer_start(tmr->timeri, tmr->ticks); 423 tmr->running = 1; 424 ktime_get_ts64(&tmr->last_update); 425 return 0; 426 } 427 428 int snd_seq_timer_continue(struct snd_seq_timer *tmr) 429 { 430 unsigned long flags; 431 int err; 432 433 spin_lock_irqsave(&tmr->lock, flags); 434 err = seq_timer_continue(tmr); 435 spin_unlock_irqrestore(&tmr->lock, flags); 436 return err; 437 } 438 439 /* return current 'real' time. use timeofday() to get better granularity. */ 440 snd_seq_real_time_t snd_seq_timer_get_cur_time(struct snd_seq_timer *tmr) 441 { 442 snd_seq_real_time_t cur_time; 443 unsigned long flags; 444 445 spin_lock_irqsave(&tmr->lock, flags); 446 cur_time = tmr->cur_time; 447 if (tmr->running) { 448 struct timespec64 tm; 449 450 ktime_get_ts64(&tm); 451 tm = timespec64_sub(tm, tmr->last_update); 452 cur_time.tv_nsec += tm.tv_nsec; 453 cur_time.tv_sec += tm.tv_sec; 454 snd_seq_sanity_real_time(&cur_time); 455 } 456 spin_unlock_irqrestore(&tmr->lock, flags); 457 return cur_time; 458 } 459 460 /* TODO: use interpolation on tick queue (will only be useful for very 461 high PPQ values) */ 462 snd_seq_tick_time_t snd_seq_timer_get_cur_tick(struct snd_seq_timer *tmr) 463 { 464 return tmr->tick.cur_tick; 465 } 466 467 468 #ifdef CONFIG_SND_PROC_FS 469 /* exported to seq_info.c */ 470 void snd_seq_info_timer_read(struct snd_info_entry *entry, 471 struct snd_info_buffer *buffer) 472 { 473 int idx; 474 struct snd_seq_queue *q; 475 struct snd_seq_timer *tmr; 476 struct snd_timer_instance *ti; 477 unsigned long resolution; 478 479 for (idx = 0; idx < SNDRV_SEQ_MAX_QUEUES; idx++) { 480 q = queueptr(idx); 481 if (q == NULL) 482 continue; 483 if ((tmr = q->timer) == NULL || 484 (ti = tmr->timeri) == NULL) { 485 queuefree(q); 486 continue; 487 } 488 snd_iprintf(buffer, "Timer for queue %i : %s\n", q->queue, ti->timer->name); 489 resolution = snd_timer_resolution(ti) * tmr->ticks; 490 snd_iprintf(buffer, " Period time : %lu.%09lu\n", resolution / 1000000000, resolution % 1000000000); 491 snd_iprintf(buffer, " Skew : %u / %u\n", tmr->skew, tmr->skew_base); 492 queuefree(q); 493 } 494 } 495 #endif /* CONFIG_SND_PROC_FS */ 496 497