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 /* setup defaults */ 94 tmr->ppq = 96; /* 96 PPQ */ 95 tmr->tempo = 500000; /* 120 BPM */ 96 snd_seq_timer_set_tick_resolution(tmr); 97 tmr->running = 0; 98 99 tmr->type = SNDRV_SEQ_TIMER_ALSA; 100 tmr->alsa_id.dev_class = seq_default_timer_class; 101 tmr->alsa_id.dev_sclass = seq_default_timer_sclass; 102 tmr->alsa_id.card = seq_default_timer_card; 103 tmr->alsa_id.device = seq_default_timer_device; 104 tmr->alsa_id.subdevice = seq_default_timer_subdevice; 105 tmr->preferred_resolution = seq_default_timer_resolution; 106 107 tmr->skew = tmr->skew_base = SKEW_BASE; 108 } 109 110 void snd_seq_timer_reset(struct snd_seq_timer * tmr) 111 { 112 unsigned long flags; 113 114 spin_lock_irqsave(&tmr->lock, flags); 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 spin_unlock_irqrestore(&tmr->lock, flags); 124 } 125 126 127 /* called by timer interrupt routine. the period time since previous invocation is passed */ 128 static void snd_seq_timer_interrupt(struct snd_timer_instance *timeri, 129 unsigned long resolution, 130 unsigned long ticks) 131 { 132 unsigned long flags; 133 struct snd_seq_queue *q = timeri->callback_data; 134 struct snd_seq_timer *tmr; 135 136 if (q == NULL) 137 return; 138 tmr = q->timer; 139 if (tmr == NULL) 140 return; 141 if (!tmr->running) 142 return; 143 144 resolution *= ticks; 145 if (tmr->skew != tmr->skew_base) { 146 /* FIXME: assuming skew_base = 0x10000 */ 147 resolution = (resolution >> 16) * tmr->skew + 148 (((resolution & 0xffff) * tmr->skew) >> 16); 149 } 150 151 spin_lock_irqsave(&tmr->lock, flags); 152 153 /* update timer */ 154 snd_seq_inc_time_nsec(&tmr->cur_time, resolution); 155 156 /* calculate current tick */ 157 snd_seq_timer_update_tick(&tmr->tick, resolution); 158 159 /* register actual time of this timer update */ 160 do_gettimeofday(&tmr->last_update); 161 162 spin_unlock_irqrestore(&tmr->lock, flags); 163 164 /* check queues and dispatch events */ 165 snd_seq_check_queue(q, 1, 0); 166 } 167 168 /* set current tempo */ 169 int snd_seq_timer_set_tempo(struct snd_seq_timer * tmr, int tempo) 170 { 171 unsigned long flags; 172 173 if (snd_BUG_ON(!tmr)) 174 return -EINVAL; 175 if (tempo <= 0) 176 return -EINVAL; 177 spin_lock_irqsave(&tmr->lock, flags); 178 if ((unsigned int)tempo != tmr->tempo) { 179 tmr->tempo = tempo; 180 snd_seq_timer_set_tick_resolution(tmr); 181 } 182 spin_unlock_irqrestore(&tmr->lock, flags); 183 return 0; 184 } 185 186 /* set current ppq */ 187 int snd_seq_timer_set_ppq(struct snd_seq_timer * tmr, int ppq) 188 { 189 unsigned long flags; 190 191 if (snd_BUG_ON(!tmr)) 192 return -EINVAL; 193 if (ppq <= 0) 194 return -EINVAL; 195 spin_lock_irqsave(&tmr->lock, flags); 196 if (tmr->running && (ppq != tmr->ppq)) { 197 /* refuse to change ppq on running timers */ 198 /* because it will upset the song position (ticks) */ 199 spin_unlock_irqrestore(&tmr->lock, flags); 200 pr_debug("ALSA: seq: cannot change ppq of a running timer\n"); 201 return -EBUSY; 202 } 203 204 tmr->ppq = ppq; 205 snd_seq_timer_set_tick_resolution(tmr); 206 spin_unlock_irqrestore(&tmr->lock, flags); 207 return 0; 208 } 209 210 /* set current tick position */ 211 int snd_seq_timer_set_position_tick(struct snd_seq_timer *tmr, 212 snd_seq_tick_time_t position) 213 { 214 unsigned long flags; 215 216 if (snd_BUG_ON(!tmr)) 217 return -EINVAL; 218 219 spin_lock_irqsave(&tmr->lock, flags); 220 tmr->tick.cur_tick = position; 221 tmr->tick.fraction = 0; 222 spin_unlock_irqrestore(&tmr->lock, flags); 223 return 0; 224 } 225 226 /* set current real-time position */ 227 int snd_seq_timer_set_position_time(struct snd_seq_timer *tmr, 228 snd_seq_real_time_t position) 229 { 230 unsigned long flags; 231 232 if (snd_BUG_ON(!tmr)) 233 return -EINVAL; 234 235 snd_seq_sanity_real_time(&position); 236 spin_lock_irqsave(&tmr->lock, flags); 237 tmr->cur_time = position; 238 spin_unlock_irqrestore(&tmr->lock, flags); 239 return 0; 240 } 241 242 /* set timer skew */ 243 int snd_seq_timer_set_skew(struct snd_seq_timer *tmr, unsigned int skew, 244 unsigned int base) 245 { 246 unsigned long flags; 247 248 if (snd_BUG_ON(!tmr)) 249 return -EINVAL; 250 251 /* FIXME */ 252 if (base != SKEW_BASE) { 253 pr_debug("ALSA: seq: invalid skew base 0x%x\n", base); 254 return -EINVAL; 255 } 256 spin_lock_irqsave(&tmr->lock, flags); 257 tmr->skew = skew; 258 spin_unlock_irqrestore(&tmr->lock, flags); 259 return 0; 260 } 261 262 int snd_seq_timer_open(struct snd_seq_queue *q) 263 { 264 struct snd_timer_instance *t; 265 struct snd_seq_timer *tmr; 266 char str[32]; 267 int err; 268 269 tmr = q->timer; 270 if (snd_BUG_ON(!tmr)) 271 return -EINVAL; 272 if (tmr->timeri) 273 return -EBUSY; 274 sprintf(str, "sequencer queue %i", q->queue); 275 if (tmr->type != SNDRV_SEQ_TIMER_ALSA) /* standard ALSA timer */ 276 return -EINVAL; 277 if (tmr->alsa_id.dev_class != SNDRV_TIMER_CLASS_SLAVE) 278 tmr->alsa_id.dev_sclass = SNDRV_TIMER_SCLASS_SEQUENCER; 279 err = snd_timer_open(&t, str, &tmr->alsa_id, q->queue); 280 if (err < 0 && tmr->alsa_id.dev_class != SNDRV_TIMER_CLASS_SLAVE) { 281 if (tmr->alsa_id.dev_class != SNDRV_TIMER_CLASS_GLOBAL || 282 tmr->alsa_id.device != SNDRV_TIMER_GLOBAL_SYSTEM) { 283 struct snd_timer_id tid; 284 memset(&tid, 0, sizeof(tid)); 285 tid.dev_class = SNDRV_TIMER_CLASS_GLOBAL; 286 tid.dev_sclass = SNDRV_TIMER_SCLASS_SEQUENCER; 287 tid.card = -1; 288 tid.device = SNDRV_TIMER_GLOBAL_SYSTEM; 289 err = snd_timer_open(&t, str, &tid, q->queue); 290 } 291 } 292 if (err < 0) { 293 pr_err("ALSA: seq fatal error: cannot create timer (%i)\n", err); 294 return err; 295 } 296 t->callback = snd_seq_timer_interrupt; 297 t->callback_data = q; 298 t->flags |= SNDRV_TIMER_IFLG_AUTO; 299 tmr->timeri = t; 300 return 0; 301 } 302 303 int snd_seq_timer_close(struct snd_seq_queue *q) 304 { 305 struct snd_seq_timer *tmr; 306 307 tmr = q->timer; 308 if (snd_BUG_ON(!tmr)) 309 return -EINVAL; 310 if (tmr->timeri) { 311 snd_timer_stop(tmr->timeri); 312 snd_timer_close(tmr->timeri); 313 tmr->timeri = NULL; 314 } 315 return 0; 316 } 317 318 int snd_seq_timer_stop(struct snd_seq_timer * tmr) 319 { 320 if (! tmr->timeri) 321 return -EINVAL; 322 if (!tmr->running) 323 return 0; 324 tmr->running = 0; 325 snd_timer_pause(tmr->timeri); 326 return 0; 327 } 328 329 static int initialize_timer(struct snd_seq_timer *tmr) 330 { 331 struct snd_timer *t; 332 unsigned long freq; 333 334 t = tmr->timeri->timer; 335 if (snd_BUG_ON(!t)) 336 return -EINVAL; 337 338 freq = tmr->preferred_resolution; 339 if (!freq) 340 freq = DEFAULT_FREQUENCY; 341 else if (freq < MIN_FREQUENCY) 342 freq = MIN_FREQUENCY; 343 else if (freq > MAX_FREQUENCY) 344 freq = MAX_FREQUENCY; 345 346 tmr->ticks = 1; 347 if (!(t->hw.flags & SNDRV_TIMER_HW_SLAVE)) { 348 unsigned long r = t->hw.resolution; 349 if (! r && t->hw.c_resolution) 350 r = t->hw.c_resolution(t); 351 if (r) { 352 tmr->ticks = (unsigned int)(1000000000uL / (r * freq)); 353 if (! tmr->ticks) 354 tmr->ticks = 1; 355 } 356 } 357 tmr->initialized = 1; 358 return 0; 359 } 360 361 int snd_seq_timer_start(struct snd_seq_timer * tmr) 362 { 363 if (! tmr->timeri) 364 return -EINVAL; 365 if (tmr->running) 366 snd_seq_timer_stop(tmr); 367 snd_seq_timer_reset(tmr); 368 if (initialize_timer(tmr) < 0) 369 return -EINVAL; 370 snd_timer_start(tmr->timeri, tmr->ticks); 371 tmr->running = 1; 372 do_gettimeofday(&tmr->last_update); 373 return 0; 374 } 375 376 int snd_seq_timer_continue(struct snd_seq_timer * tmr) 377 { 378 if (! tmr->timeri) 379 return -EINVAL; 380 if (tmr->running) 381 return -EBUSY; 382 if (! tmr->initialized) { 383 snd_seq_timer_reset(tmr); 384 if (initialize_timer(tmr) < 0) 385 return -EINVAL; 386 } 387 snd_timer_start(tmr->timeri, tmr->ticks); 388 tmr->running = 1; 389 do_gettimeofday(&tmr->last_update); 390 return 0; 391 } 392 393 /* return current 'real' time. use timeofday() to get better granularity. */ 394 snd_seq_real_time_t snd_seq_timer_get_cur_time(struct snd_seq_timer *tmr) 395 { 396 snd_seq_real_time_t cur_time; 397 398 cur_time = tmr->cur_time; 399 if (tmr->running) { 400 struct timeval tm; 401 int usec; 402 do_gettimeofday(&tm); 403 usec = (int)(tm.tv_usec - tmr->last_update.tv_usec); 404 if (usec < 0) { 405 cur_time.tv_nsec += (1000000 + usec) * 1000; 406 cur_time.tv_sec += tm.tv_sec - tmr->last_update.tv_sec - 1; 407 } else { 408 cur_time.tv_nsec += usec * 1000; 409 cur_time.tv_sec += tm.tv_sec - tmr->last_update.tv_sec; 410 } 411 snd_seq_sanity_real_time(&cur_time); 412 } 413 414 return cur_time; 415 } 416 417 /* TODO: use interpolation on tick queue (will only be useful for very 418 high PPQ values) */ 419 snd_seq_tick_time_t snd_seq_timer_get_cur_tick(struct snd_seq_timer *tmr) 420 { 421 return tmr->tick.cur_tick; 422 } 423 424 425 #ifdef CONFIG_SND_PROC_FS 426 /* exported to seq_info.c */ 427 void snd_seq_info_timer_read(struct snd_info_entry *entry, 428 struct snd_info_buffer *buffer) 429 { 430 int idx; 431 struct snd_seq_queue *q; 432 struct snd_seq_timer *tmr; 433 struct snd_timer_instance *ti; 434 unsigned long resolution; 435 436 for (idx = 0; idx < SNDRV_SEQ_MAX_QUEUES; idx++) { 437 q = queueptr(idx); 438 if (q == NULL) 439 continue; 440 if ((tmr = q->timer) == NULL || 441 (ti = tmr->timeri) == NULL) { 442 queuefree(q); 443 continue; 444 } 445 snd_iprintf(buffer, "Timer for queue %i : %s\n", q->queue, ti->timer->name); 446 resolution = snd_timer_resolution(ti) * tmr->ticks; 447 snd_iprintf(buffer, " Period time : %lu.%09lu\n", resolution / 1000000000, resolution % 1000000000); 448 snd_iprintf(buffer, " Skew : %u / %u\n", tmr->skew, tmr->skew_base); 449 queuefree(q); 450 } 451 } 452 #endif /* CONFIG_SND_PROC_FS */ 453 454