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 == NULL) { 60 snd_printd("malloc failed for snd_seq_timer_new() \n"); 61 return NULL; 62 } 63 spin_lock_init(&tmr->lock); 64 65 /* reset setup to defaults */ 66 snd_seq_timer_defaults(tmr); 67 68 /* reset time */ 69 snd_seq_timer_reset(tmr); 70 71 return tmr; 72 } 73 74 /* delete timer (destructor) */ 75 void snd_seq_timer_delete(struct snd_seq_timer **tmr) 76 { 77 struct snd_seq_timer *t = *tmr; 78 *tmr = NULL; 79 80 if (t == NULL) { 81 snd_printd("oops: snd_seq_timer_delete() called with NULL timer\n"); 82 return; 83 } 84 t->running = 0; 85 86 /* reset time */ 87 snd_seq_timer_stop(t); 88 snd_seq_timer_reset(t); 89 90 kfree(t); 91 } 92 93 void snd_seq_timer_defaults(struct snd_seq_timer * tmr) 94 { 95 /* setup defaults */ 96 tmr->ppq = 96; /* 96 PPQ */ 97 tmr->tempo = 500000; /* 120 BPM */ 98 snd_seq_timer_set_tick_resolution(tmr); 99 tmr->running = 0; 100 101 tmr->type = SNDRV_SEQ_TIMER_ALSA; 102 tmr->alsa_id.dev_class = seq_default_timer_class; 103 tmr->alsa_id.dev_sclass = seq_default_timer_sclass; 104 tmr->alsa_id.card = seq_default_timer_card; 105 tmr->alsa_id.device = seq_default_timer_device; 106 tmr->alsa_id.subdevice = seq_default_timer_subdevice; 107 tmr->preferred_resolution = seq_default_timer_resolution; 108 109 tmr->skew = tmr->skew_base = SKEW_BASE; 110 } 111 112 void snd_seq_timer_reset(struct snd_seq_timer * tmr) 113 { 114 unsigned long flags; 115 116 spin_lock_irqsave(&tmr->lock, flags); 117 118 /* reset time & songposition */ 119 tmr->cur_time.tv_sec = 0; 120 tmr->cur_time.tv_nsec = 0; 121 122 tmr->tick.cur_tick = 0; 123 tmr->tick.fraction = 0; 124 125 spin_unlock_irqrestore(&tmr->lock, flags); 126 } 127 128 129 /* called by timer interrupt routine. the period time since previous invocation is passed */ 130 static void snd_seq_timer_interrupt(struct snd_timer_instance *timeri, 131 unsigned long resolution, 132 unsigned long ticks) 133 { 134 unsigned long flags; 135 struct snd_seq_queue *q = timeri->callback_data; 136 struct snd_seq_timer *tmr; 137 138 if (q == NULL) 139 return; 140 tmr = q->timer; 141 if (tmr == NULL) 142 return; 143 if (!tmr->running) 144 return; 145 146 resolution *= ticks; 147 if (tmr->skew != tmr->skew_base) { 148 /* FIXME: assuming skew_base = 0x10000 */ 149 resolution = (resolution >> 16) * tmr->skew + 150 (((resolution & 0xffff) * tmr->skew) >> 16); 151 } 152 153 spin_lock_irqsave(&tmr->lock, flags); 154 155 /* update timer */ 156 snd_seq_inc_time_nsec(&tmr->cur_time, resolution); 157 158 /* calculate current tick */ 159 snd_seq_timer_update_tick(&tmr->tick, resolution); 160 161 /* register actual time of this timer update */ 162 do_gettimeofday(&tmr->last_update); 163 164 spin_unlock_irqrestore(&tmr->lock, flags); 165 166 /* check queues and dispatch events */ 167 snd_seq_check_queue(q, 1, 0); 168 } 169 170 /* set current tempo */ 171 int snd_seq_timer_set_tempo(struct snd_seq_timer * tmr, int tempo) 172 { 173 unsigned long flags; 174 175 if (snd_BUG_ON(!tmr)) 176 return -EINVAL; 177 if (tempo <= 0) 178 return -EINVAL; 179 spin_lock_irqsave(&tmr->lock, flags); 180 if ((unsigned int)tempo != tmr->tempo) { 181 tmr->tempo = tempo; 182 snd_seq_timer_set_tick_resolution(tmr); 183 } 184 spin_unlock_irqrestore(&tmr->lock, flags); 185 return 0; 186 } 187 188 /* set current ppq */ 189 int snd_seq_timer_set_ppq(struct snd_seq_timer * tmr, int ppq) 190 { 191 unsigned long flags; 192 193 if (snd_BUG_ON(!tmr)) 194 return -EINVAL; 195 if (ppq <= 0) 196 return -EINVAL; 197 spin_lock_irqsave(&tmr->lock, flags); 198 if (tmr->running && (ppq != tmr->ppq)) { 199 /* refuse to change ppq on running timers */ 200 /* because it will upset the song position (ticks) */ 201 spin_unlock_irqrestore(&tmr->lock, flags); 202 snd_printd("seq: cannot change ppq of a running timer\n"); 203 return -EBUSY; 204 } 205 206 tmr->ppq = ppq; 207 snd_seq_timer_set_tick_resolution(tmr); 208 spin_unlock_irqrestore(&tmr->lock, flags); 209 return 0; 210 } 211 212 /* set current tick position */ 213 int snd_seq_timer_set_position_tick(struct snd_seq_timer *tmr, 214 snd_seq_tick_time_t position) 215 { 216 unsigned long flags; 217 218 if (snd_BUG_ON(!tmr)) 219 return -EINVAL; 220 221 spin_lock_irqsave(&tmr->lock, flags); 222 tmr->tick.cur_tick = position; 223 tmr->tick.fraction = 0; 224 spin_unlock_irqrestore(&tmr->lock, flags); 225 return 0; 226 } 227 228 /* set current real-time position */ 229 int snd_seq_timer_set_position_time(struct snd_seq_timer *tmr, 230 snd_seq_real_time_t position) 231 { 232 unsigned long flags; 233 234 if (snd_BUG_ON(!tmr)) 235 return -EINVAL; 236 237 snd_seq_sanity_real_time(&position); 238 spin_lock_irqsave(&tmr->lock, flags); 239 tmr->cur_time = position; 240 spin_unlock_irqrestore(&tmr->lock, flags); 241 return 0; 242 } 243 244 /* set timer skew */ 245 int snd_seq_timer_set_skew(struct snd_seq_timer *tmr, unsigned int skew, 246 unsigned int base) 247 { 248 unsigned long flags; 249 250 if (snd_BUG_ON(!tmr)) 251 return -EINVAL; 252 253 /* FIXME */ 254 if (base != SKEW_BASE) { 255 snd_printd("invalid skew base 0x%x\n", base); 256 return -EINVAL; 257 } 258 spin_lock_irqsave(&tmr->lock, flags); 259 tmr->skew = skew; 260 spin_unlock_irqrestore(&tmr->lock, flags); 261 return 0; 262 } 263 264 int snd_seq_timer_open(struct snd_seq_queue *q) 265 { 266 struct snd_timer_instance *t; 267 struct snd_seq_timer *tmr; 268 char str[32]; 269 int err; 270 271 tmr = q->timer; 272 if (snd_BUG_ON(!tmr)) 273 return -EINVAL; 274 if (tmr->timeri) 275 return -EBUSY; 276 sprintf(str, "sequencer queue %i", q->queue); 277 if (tmr->type != SNDRV_SEQ_TIMER_ALSA) /* standard ALSA timer */ 278 return -EINVAL; 279 if (tmr->alsa_id.dev_class != SNDRV_TIMER_CLASS_SLAVE) 280 tmr->alsa_id.dev_sclass = SNDRV_TIMER_SCLASS_SEQUENCER; 281 err = snd_timer_open(&t, str, &tmr->alsa_id, q->queue); 282 if (err < 0 && tmr->alsa_id.dev_class != SNDRV_TIMER_CLASS_SLAVE) { 283 if (tmr->alsa_id.dev_class != SNDRV_TIMER_CLASS_GLOBAL || 284 tmr->alsa_id.device != SNDRV_TIMER_GLOBAL_SYSTEM) { 285 struct snd_timer_id tid; 286 memset(&tid, 0, sizeof(tid)); 287 tid.dev_class = SNDRV_TIMER_CLASS_GLOBAL; 288 tid.dev_sclass = SNDRV_TIMER_SCLASS_SEQUENCER; 289 tid.card = -1; 290 tid.device = SNDRV_TIMER_GLOBAL_SYSTEM; 291 err = snd_timer_open(&t, str, &tid, q->queue); 292 } 293 } 294 if (err < 0) { 295 snd_printk(KERN_ERR "seq fatal error: cannot create timer (%i)\n", err); 296 return err; 297 } 298 t->callback = snd_seq_timer_interrupt; 299 t->callback_data = q; 300 t->flags |= SNDRV_TIMER_IFLG_AUTO; 301 tmr->timeri = t; 302 return 0; 303 } 304 305 int snd_seq_timer_close(struct snd_seq_queue *q) 306 { 307 struct snd_seq_timer *tmr; 308 309 tmr = q->timer; 310 if (snd_BUG_ON(!tmr)) 311 return -EINVAL; 312 if (tmr->timeri) { 313 snd_timer_stop(tmr->timeri); 314 snd_timer_close(tmr->timeri); 315 tmr->timeri = NULL; 316 } 317 return 0; 318 } 319 320 int snd_seq_timer_stop(struct snd_seq_timer * tmr) 321 { 322 if (! tmr->timeri) 323 return -EINVAL; 324 if (!tmr->running) 325 return 0; 326 tmr->running = 0; 327 snd_timer_pause(tmr->timeri); 328 return 0; 329 } 330 331 static int initialize_timer(struct snd_seq_timer *tmr) 332 { 333 struct snd_timer *t; 334 unsigned long freq; 335 336 t = tmr->timeri->timer; 337 if (snd_BUG_ON(!t)) 338 return -EINVAL; 339 340 freq = tmr->preferred_resolution; 341 if (!freq) 342 freq = DEFAULT_FREQUENCY; 343 else if (freq < MIN_FREQUENCY) 344 freq = MIN_FREQUENCY; 345 else if (freq > MAX_FREQUENCY) 346 freq = MAX_FREQUENCY; 347 348 tmr->ticks = 1; 349 if (!(t->hw.flags & SNDRV_TIMER_HW_SLAVE)) { 350 unsigned long r = t->hw.resolution; 351 if (! r && t->hw.c_resolution) 352 r = t->hw.c_resolution(t); 353 if (r) { 354 tmr->ticks = (unsigned int)(1000000000uL / (r * freq)); 355 if (! tmr->ticks) 356 tmr->ticks = 1; 357 } 358 } 359 tmr->initialized = 1; 360 return 0; 361 } 362 363 int snd_seq_timer_start(struct snd_seq_timer * tmr) 364 { 365 if (! tmr->timeri) 366 return -EINVAL; 367 if (tmr->running) 368 snd_seq_timer_stop(tmr); 369 snd_seq_timer_reset(tmr); 370 if (initialize_timer(tmr) < 0) 371 return -EINVAL; 372 snd_timer_start(tmr->timeri, tmr->ticks); 373 tmr->running = 1; 374 do_gettimeofday(&tmr->last_update); 375 return 0; 376 } 377 378 int snd_seq_timer_continue(struct snd_seq_timer * tmr) 379 { 380 if (! tmr->timeri) 381 return -EINVAL; 382 if (tmr->running) 383 return -EBUSY; 384 if (! tmr->initialized) { 385 snd_seq_timer_reset(tmr); 386 if (initialize_timer(tmr) < 0) 387 return -EINVAL; 388 } 389 snd_timer_start(tmr->timeri, tmr->ticks); 390 tmr->running = 1; 391 do_gettimeofday(&tmr->last_update); 392 return 0; 393 } 394 395 /* return current 'real' time. use timeofday() to get better granularity. */ 396 snd_seq_real_time_t snd_seq_timer_get_cur_time(struct snd_seq_timer *tmr) 397 { 398 snd_seq_real_time_t cur_time; 399 400 cur_time = tmr->cur_time; 401 if (tmr->running) { 402 struct timeval tm; 403 int usec; 404 do_gettimeofday(&tm); 405 usec = (int)(tm.tv_usec - tmr->last_update.tv_usec); 406 if (usec < 0) { 407 cur_time.tv_nsec += (1000000 + usec) * 1000; 408 cur_time.tv_sec += tm.tv_sec - tmr->last_update.tv_sec - 1; 409 } else { 410 cur_time.tv_nsec += usec * 1000; 411 cur_time.tv_sec += tm.tv_sec - tmr->last_update.tv_sec; 412 } 413 snd_seq_sanity_real_time(&cur_time); 414 } 415 416 return cur_time; 417 } 418 419 /* TODO: use interpolation on tick queue (will only be useful for very 420 high PPQ values) */ 421 snd_seq_tick_time_t snd_seq_timer_get_cur_tick(struct snd_seq_timer *tmr) 422 { 423 return tmr->tick.cur_tick; 424 } 425 426 427 #ifdef CONFIG_PROC_FS 428 /* exported to seq_info.c */ 429 void snd_seq_info_timer_read(struct snd_info_entry *entry, 430 struct snd_info_buffer *buffer) 431 { 432 int idx; 433 struct snd_seq_queue *q; 434 struct snd_seq_timer *tmr; 435 struct snd_timer_instance *ti; 436 unsigned long resolution; 437 438 for (idx = 0; idx < SNDRV_SEQ_MAX_QUEUES; idx++) { 439 q = queueptr(idx); 440 if (q == NULL) 441 continue; 442 if ((tmr = q->timer) == NULL || 443 (ti = tmr->timeri) == NULL) { 444 queuefree(q); 445 continue; 446 } 447 snd_iprintf(buffer, "Timer for queue %i : %s\n", q->queue, ti->timer->name); 448 resolution = snd_timer_resolution(ti) * tmr->ticks; 449 snd_iprintf(buffer, " Period time : %lu.%09lu\n", resolution / 1000000000, resolution % 1000000000); 450 snd_iprintf(buffer, " Skew : %u / %u\n", tmr->skew, tmr->skew_base); 451 queuefree(q); 452 } 453 } 454 #endif /* CONFIG_PROC_FS */ 455 456