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 do_gettimeofday(&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 ppq */ 195 int snd_seq_timer_set_ppq(struct snd_seq_timer * tmr, int ppq) 196 { 197 unsigned long flags; 198 199 if (snd_BUG_ON(!tmr)) 200 return -EINVAL; 201 if (ppq <= 0) 202 return -EINVAL; 203 spin_lock_irqsave(&tmr->lock, flags); 204 if (tmr->running && (ppq != tmr->ppq)) { 205 /* refuse to change ppq on running timers */ 206 /* because it will upset the song position (ticks) */ 207 spin_unlock_irqrestore(&tmr->lock, flags); 208 pr_debug("ALSA: seq: cannot change ppq of a running timer\n"); 209 return -EBUSY; 210 } 211 212 tmr->ppq = ppq; 213 snd_seq_timer_set_tick_resolution(tmr); 214 spin_unlock_irqrestore(&tmr->lock, flags); 215 return 0; 216 } 217 218 /* set current tick position */ 219 int snd_seq_timer_set_position_tick(struct snd_seq_timer *tmr, 220 snd_seq_tick_time_t position) 221 { 222 unsigned long flags; 223 224 if (snd_BUG_ON(!tmr)) 225 return -EINVAL; 226 227 spin_lock_irqsave(&tmr->lock, flags); 228 tmr->tick.cur_tick = position; 229 tmr->tick.fraction = 0; 230 spin_unlock_irqrestore(&tmr->lock, flags); 231 return 0; 232 } 233 234 /* set current real-time position */ 235 int snd_seq_timer_set_position_time(struct snd_seq_timer *tmr, 236 snd_seq_real_time_t position) 237 { 238 unsigned long flags; 239 240 if (snd_BUG_ON(!tmr)) 241 return -EINVAL; 242 243 snd_seq_sanity_real_time(&position); 244 spin_lock_irqsave(&tmr->lock, flags); 245 tmr->cur_time = position; 246 spin_unlock_irqrestore(&tmr->lock, flags); 247 return 0; 248 } 249 250 /* set timer skew */ 251 int snd_seq_timer_set_skew(struct snd_seq_timer *tmr, unsigned int skew, 252 unsigned int base) 253 { 254 unsigned long flags; 255 256 if (snd_BUG_ON(!tmr)) 257 return -EINVAL; 258 259 /* FIXME */ 260 if (base != SKEW_BASE) { 261 pr_debug("ALSA: seq: invalid skew base 0x%x\n", base); 262 return -EINVAL; 263 } 264 spin_lock_irqsave(&tmr->lock, flags); 265 tmr->skew = skew; 266 spin_unlock_irqrestore(&tmr->lock, flags); 267 return 0; 268 } 269 270 int snd_seq_timer_open(struct snd_seq_queue *q) 271 { 272 struct snd_timer_instance *t; 273 struct snd_seq_timer *tmr; 274 char str[32]; 275 int err; 276 277 tmr = q->timer; 278 if (snd_BUG_ON(!tmr)) 279 return -EINVAL; 280 if (tmr->timeri) 281 return -EBUSY; 282 sprintf(str, "sequencer queue %i", q->queue); 283 if (tmr->type != SNDRV_SEQ_TIMER_ALSA) /* standard ALSA timer */ 284 return -EINVAL; 285 if (tmr->alsa_id.dev_class != SNDRV_TIMER_CLASS_SLAVE) 286 tmr->alsa_id.dev_sclass = SNDRV_TIMER_SCLASS_SEQUENCER; 287 err = snd_timer_open(&t, str, &tmr->alsa_id, q->queue); 288 if (err < 0 && tmr->alsa_id.dev_class != SNDRV_TIMER_CLASS_SLAVE) { 289 if (tmr->alsa_id.dev_class != SNDRV_TIMER_CLASS_GLOBAL || 290 tmr->alsa_id.device != SNDRV_TIMER_GLOBAL_SYSTEM) { 291 struct snd_timer_id tid; 292 memset(&tid, 0, sizeof(tid)); 293 tid.dev_class = SNDRV_TIMER_CLASS_GLOBAL; 294 tid.dev_sclass = SNDRV_TIMER_SCLASS_SEQUENCER; 295 tid.card = -1; 296 tid.device = SNDRV_TIMER_GLOBAL_SYSTEM; 297 err = snd_timer_open(&t, str, &tid, q->queue); 298 } 299 } 300 if (err < 0) { 301 pr_err("ALSA: seq fatal error: cannot create timer (%i)\n", err); 302 return err; 303 } 304 t->callback = snd_seq_timer_interrupt; 305 t->callback_data = q; 306 t->flags |= SNDRV_TIMER_IFLG_AUTO; 307 spin_lock_irq(&tmr->lock); 308 tmr->timeri = t; 309 spin_unlock_irq(&tmr->lock); 310 return 0; 311 } 312 313 int snd_seq_timer_close(struct snd_seq_queue *q) 314 { 315 struct snd_seq_timer *tmr; 316 struct snd_timer_instance *t; 317 318 tmr = q->timer; 319 if (snd_BUG_ON(!tmr)) 320 return -EINVAL; 321 spin_lock_irq(&tmr->lock); 322 t = tmr->timeri; 323 tmr->timeri = NULL; 324 spin_unlock_irq(&tmr->lock); 325 if (t) 326 snd_timer_close(t); 327 return 0; 328 } 329 330 static int seq_timer_stop(struct snd_seq_timer *tmr) 331 { 332 if (! tmr->timeri) 333 return -EINVAL; 334 if (!tmr->running) 335 return 0; 336 tmr->running = 0; 337 snd_timer_pause(tmr->timeri); 338 return 0; 339 } 340 341 int snd_seq_timer_stop(struct snd_seq_timer *tmr) 342 { 343 unsigned long flags; 344 int err; 345 346 spin_lock_irqsave(&tmr->lock, flags); 347 err = seq_timer_stop(tmr); 348 spin_unlock_irqrestore(&tmr->lock, flags); 349 return err; 350 } 351 352 static int initialize_timer(struct snd_seq_timer *tmr) 353 { 354 struct snd_timer *t; 355 unsigned long freq; 356 357 t = tmr->timeri->timer; 358 if (snd_BUG_ON(!t)) 359 return -EINVAL; 360 361 freq = tmr->preferred_resolution; 362 if (!freq) 363 freq = DEFAULT_FREQUENCY; 364 else if (freq < MIN_FREQUENCY) 365 freq = MIN_FREQUENCY; 366 else if (freq > MAX_FREQUENCY) 367 freq = MAX_FREQUENCY; 368 369 tmr->ticks = 1; 370 if (!(t->hw.flags & SNDRV_TIMER_HW_SLAVE)) { 371 unsigned long r = t->hw.resolution; 372 if (! r && t->hw.c_resolution) 373 r = t->hw.c_resolution(t); 374 if (r) { 375 tmr->ticks = (unsigned int)(1000000000uL / (r * freq)); 376 if (! tmr->ticks) 377 tmr->ticks = 1; 378 } 379 } 380 tmr->initialized = 1; 381 return 0; 382 } 383 384 static int seq_timer_start(struct snd_seq_timer *tmr) 385 { 386 if (! tmr->timeri) 387 return -EINVAL; 388 if (tmr->running) 389 seq_timer_stop(tmr); 390 seq_timer_reset(tmr); 391 if (initialize_timer(tmr) < 0) 392 return -EINVAL; 393 snd_timer_start(tmr->timeri, tmr->ticks); 394 tmr->running = 1; 395 do_gettimeofday(&tmr->last_update); 396 return 0; 397 } 398 399 int snd_seq_timer_start(struct snd_seq_timer *tmr) 400 { 401 unsigned long flags; 402 int err; 403 404 spin_lock_irqsave(&tmr->lock, flags); 405 err = seq_timer_start(tmr); 406 spin_unlock_irqrestore(&tmr->lock, flags); 407 return err; 408 } 409 410 static int seq_timer_continue(struct snd_seq_timer *tmr) 411 { 412 if (! tmr->timeri) 413 return -EINVAL; 414 if (tmr->running) 415 return -EBUSY; 416 if (! tmr->initialized) { 417 seq_timer_reset(tmr); 418 if (initialize_timer(tmr) < 0) 419 return -EINVAL; 420 } 421 snd_timer_start(tmr->timeri, tmr->ticks); 422 tmr->running = 1; 423 do_gettimeofday(&tmr->last_update); 424 return 0; 425 } 426 427 int snd_seq_timer_continue(struct snd_seq_timer *tmr) 428 { 429 unsigned long flags; 430 int err; 431 432 spin_lock_irqsave(&tmr->lock, flags); 433 err = seq_timer_continue(tmr); 434 spin_unlock_irqrestore(&tmr->lock, flags); 435 return err; 436 } 437 438 /* return current 'real' time. use timeofday() to get better granularity. */ 439 snd_seq_real_time_t snd_seq_timer_get_cur_time(struct snd_seq_timer *tmr) 440 { 441 snd_seq_real_time_t cur_time; 442 unsigned long flags; 443 444 spin_lock_irqsave(&tmr->lock, flags); 445 cur_time = tmr->cur_time; 446 if (tmr->running) { 447 struct timeval tm; 448 int usec; 449 do_gettimeofday(&tm); 450 usec = (int)(tm.tv_usec - tmr->last_update.tv_usec); 451 if (usec < 0) { 452 cur_time.tv_nsec += (1000000 + usec) * 1000; 453 cur_time.tv_sec += tm.tv_sec - tmr->last_update.tv_sec - 1; 454 } else { 455 cur_time.tv_nsec += usec * 1000; 456 cur_time.tv_sec += tm.tv_sec - tmr->last_update.tv_sec; 457 } 458 snd_seq_sanity_real_time(&cur_time); 459 } 460 spin_unlock_irqrestore(&tmr->lock, flags); 461 return cur_time; 462 } 463 464 /* TODO: use interpolation on tick queue (will only be useful for very 465 high PPQ values) */ 466 snd_seq_tick_time_t snd_seq_timer_get_cur_tick(struct snd_seq_timer *tmr) 467 { 468 return tmr->tick.cur_tick; 469 } 470 471 472 #ifdef CONFIG_SND_PROC_FS 473 /* exported to seq_info.c */ 474 void snd_seq_info_timer_read(struct snd_info_entry *entry, 475 struct snd_info_buffer *buffer) 476 { 477 int idx; 478 struct snd_seq_queue *q; 479 struct snd_seq_timer *tmr; 480 struct snd_timer_instance *ti; 481 unsigned long resolution; 482 483 for (idx = 0; idx < SNDRV_SEQ_MAX_QUEUES; idx++) { 484 q = queueptr(idx); 485 if (q == NULL) 486 continue; 487 if ((tmr = q->timer) == NULL || 488 (ti = tmr->timeri) == NULL) { 489 queuefree(q); 490 continue; 491 } 492 snd_iprintf(buffer, "Timer for queue %i : %s\n", q->queue, ti->timer->name); 493 resolution = snd_timer_resolution(ti) * tmr->ticks; 494 snd_iprintf(buffer, " Period time : %lu.%09lu\n", resolution / 1000000000, resolution % 1000000000); 495 snd_iprintf(buffer, " Skew : %u / %u\n", tmr->skew, tmr->skew_base); 496 queuefree(q); 497 } 498 } 499 #endif /* CONFIG_SND_PROC_FS */ 500 501