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_tick *tick, 37 int tempo, int ppq) 38 { 39 if (tempo < 1000000) 40 tick->resolution = (tempo * 1000) / ppq; 41 else { 42 /* might overflow.. */ 43 unsigned int s; 44 s = tempo % ppq; 45 s = (s * 1000) / ppq; 46 tick->resolution = (tempo / ppq) * 1000; 47 tick->resolution += s; 48 } 49 if (tick->resolution <= 0) 50 tick->resolution = 1; 51 snd_seq_timer_update_tick(tick, 0); 52 } 53 54 /* create new timer (constructor) */ 55 struct snd_seq_timer *snd_seq_timer_new(void) 56 { 57 struct snd_seq_timer *tmr; 58 59 tmr = kzalloc(sizeof(*tmr), GFP_KERNEL); 60 if (tmr == NULL) { 61 snd_printd("malloc failed for snd_seq_timer_new() \n"); 62 return NULL; 63 } 64 spin_lock_init(&tmr->lock); 65 66 /* reset setup to defaults */ 67 snd_seq_timer_defaults(tmr); 68 69 /* reset time */ 70 snd_seq_timer_reset(tmr); 71 72 return tmr; 73 } 74 75 /* delete timer (destructor) */ 76 void snd_seq_timer_delete(struct snd_seq_timer **tmr) 77 { 78 struct snd_seq_timer *t = *tmr; 79 *tmr = NULL; 80 81 if (t == NULL) { 82 snd_printd("oops: snd_seq_timer_delete() called with NULL timer\n"); 83 return; 84 } 85 t->running = 0; 86 87 /* reset time */ 88 snd_seq_timer_stop(t); 89 snd_seq_timer_reset(t); 90 91 kfree(t); 92 } 93 94 void snd_seq_timer_defaults(struct snd_seq_timer * tmr) 95 { 96 /* setup defaults */ 97 tmr->ppq = 96; /* 96 PPQ */ 98 tmr->tempo = 500000; /* 120 BPM */ 99 snd_seq_timer_set_tick_resolution(&tmr->tick, tmr->tempo, tmr->ppq); 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 } 112 113 void snd_seq_timer_reset(struct snd_seq_timer * tmr) 114 { 115 unsigned long flags; 116 117 spin_lock_irqsave(&tmr->lock, flags); 118 119 /* reset time & songposition */ 120 tmr->cur_time.tv_sec = 0; 121 tmr->cur_time.tv_nsec = 0; 122 123 tmr->tick.cur_tick = 0; 124 tmr->tick.fraction = 0; 125 126 spin_unlock_irqrestore(&tmr->lock, flags); 127 } 128 129 130 /* called by timer interrupt routine. the period time since previous invocation is passed */ 131 static void snd_seq_timer_interrupt(struct snd_timer_instance *timeri, 132 unsigned long resolution, 133 unsigned long ticks) 134 { 135 unsigned long flags; 136 struct snd_seq_queue *q = timeri->callback_data; 137 struct snd_seq_timer *tmr; 138 139 if (q == NULL) 140 return; 141 tmr = q->timer; 142 if (tmr == NULL) 143 return; 144 if (!tmr->running) 145 return; 146 147 resolution *= ticks; 148 if (tmr->skew != tmr->skew_base) { 149 /* FIXME: assuming skew_base = 0x10000 */ 150 resolution = (resolution >> 16) * tmr->skew + 151 (((resolution & 0xffff) * tmr->skew) >> 16); 152 } 153 154 spin_lock_irqsave(&tmr->lock, flags); 155 156 /* update timer */ 157 snd_seq_inc_time_nsec(&tmr->cur_time, resolution); 158 159 /* calculate current tick */ 160 snd_seq_timer_update_tick(&tmr->tick, resolution); 161 162 /* register actual time of this timer update */ 163 do_gettimeofday(&tmr->last_update); 164 165 spin_unlock_irqrestore(&tmr->lock, flags); 166 167 /* check queues and dispatch events */ 168 snd_seq_check_queue(q, 1, 0); 169 } 170 171 /* set current tempo */ 172 int snd_seq_timer_set_tempo(struct snd_seq_timer * tmr, int tempo) 173 { 174 unsigned long flags; 175 176 if (snd_BUG_ON(!tmr)) 177 return -EINVAL; 178 if (tempo <= 0) 179 return -EINVAL; 180 spin_lock_irqsave(&tmr->lock, flags); 181 if ((unsigned int)tempo != tmr->tempo) { 182 tmr->tempo = tempo; 183 snd_seq_timer_set_tick_resolution(&tmr->tick, tmr->tempo, tmr->ppq); 184 } 185 spin_unlock_irqrestore(&tmr->lock, flags); 186 return 0; 187 } 188 189 /* set current ppq */ 190 int snd_seq_timer_set_ppq(struct snd_seq_timer * tmr, int ppq) 191 { 192 unsigned long flags; 193 194 if (snd_BUG_ON(!tmr)) 195 return -EINVAL; 196 if (ppq <= 0) 197 return -EINVAL; 198 spin_lock_irqsave(&tmr->lock, flags); 199 if (tmr->running && (ppq != tmr->ppq)) { 200 /* refuse to change ppq on running timers */ 201 /* because it will upset the song position (ticks) */ 202 spin_unlock_irqrestore(&tmr->lock, flags); 203 snd_printd("seq: cannot change ppq of a running timer\n"); 204 return -EBUSY; 205 } 206 207 tmr->ppq = ppq; 208 snd_seq_timer_set_tick_resolution(&tmr->tick, tmr->tempo, tmr->ppq); 209 spin_unlock_irqrestore(&tmr->lock, flags); 210 return 0; 211 } 212 213 /* set current tick position */ 214 int snd_seq_timer_set_position_tick(struct snd_seq_timer *tmr, 215 snd_seq_tick_time_t position) 216 { 217 unsigned long flags; 218 219 if (snd_BUG_ON(!tmr)) 220 return -EINVAL; 221 222 spin_lock_irqsave(&tmr->lock, flags); 223 tmr->tick.cur_tick = position; 224 tmr->tick.fraction = 0; 225 spin_unlock_irqrestore(&tmr->lock, flags); 226 return 0; 227 } 228 229 /* set current real-time position */ 230 int snd_seq_timer_set_position_time(struct snd_seq_timer *tmr, 231 snd_seq_real_time_t position) 232 { 233 unsigned long flags; 234 235 if (snd_BUG_ON(!tmr)) 236 return -EINVAL; 237 238 snd_seq_sanity_real_time(&position); 239 spin_lock_irqsave(&tmr->lock, flags); 240 tmr->cur_time = position; 241 spin_unlock_irqrestore(&tmr->lock, flags); 242 return 0; 243 } 244 245 /* set timer skew */ 246 int snd_seq_timer_set_skew(struct snd_seq_timer *tmr, unsigned int skew, 247 unsigned int base) 248 { 249 unsigned long flags; 250 251 if (snd_BUG_ON(!tmr)) 252 return -EINVAL; 253 254 /* FIXME */ 255 if (base != SKEW_BASE) { 256 snd_printd("invalid skew base 0x%x\n", base); 257 return -EINVAL; 258 } 259 spin_lock_irqsave(&tmr->lock, flags); 260 tmr->skew = skew; 261 spin_unlock_irqrestore(&tmr->lock, flags); 262 return 0; 263 } 264 265 int snd_seq_timer_open(struct snd_seq_queue *q) 266 { 267 struct snd_timer_instance *t; 268 struct snd_seq_timer *tmr; 269 char str[32]; 270 int err; 271 272 tmr = q->timer; 273 if (snd_BUG_ON(!tmr)) 274 return -EINVAL; 275 if (tmr->timeri) 276 return -EBUSY; 277 sprintf(str, "sequencer queue %i", q->queue); 278 if (tmr->type != SNDRV_SEQ_TIMER_ALSA) /* standard ALSA timer */ 279 return -EINVAL; 280 if (tmr->alsa_id.dev_class != SNDRV_TIMER_CLASS_SLAVE) 281 tmr->alsa_id.dev_sclass = SNDRV_TIMER_SCLASS_SEQUENCER; 282 err = snd_timer_open(&t, str, &tmr->alsa_id, q->queue); 283 if (err < 0 && tmr->alsa_id.dev_class != SNDRV_TIMER_CLASS_SLAVE) { 284 if (tmr->alsa_id.dev_class != SNDRV_TIMER_CLASS_GLOBAL || 285 tmr->alsa_id.device != SNDRV_TIMER_GLOBAL_SYSTEM) { 286 struct snd_timer_id tid; 287 memset(&tid, 0, sizeof(tid)); 288 tid.dev_class = SNDRV_TIMER_CLASS_GLOBAL; 289 tid.dev_sclass = SNDRV_TIMER_SCLASS_SEQUENCER; 290 tid.card = -1; 291 tid.device = SNDRV_TIMER_GLOBAL_SYSTEM; 292 err = snd_timer_open(&t, str, &tid, q->queue); 293 } 294 if (err < 0) { 295 snd_printk(KERN_ERR "seq fatal error: cannot create timer (%i)\n", err); 296 return err; 297 } 298 } 299 t->callback = snd_seq_timer_interrupt; 300 t->callback_data = q; 301 t->flags |= SNDRV_TIMER_IFLG_AUTO; 302 tmr->timeri = t; 303 return 0; 304 } 305 306 int snd_seq_timer_close(struct snd_seq_queue *q) 307 { 308 struct snd_seq_timer *tmr; 309 310 tmr = q->timer; 311 if (snd_BUG_ON(!tmr)) 312 return -EINVAL; 313 if (tmr->timeri) { 314 snd_timer_stop(tmr->timeri); 315 snd_timer_close(tmr->timeri); 316 tmr->timeri = NULL; 317 } 318 return 0; 319 } 320 321 int snd_seq_timer_stop(struct snd_seq_timer * tmr) 322 { 323 if (! tmr->timeri) 324 return -EINVAL; 325 if (!tmr->running) 326 return 0; 327 tmr->running = 0; 328 snd_timer_pause(tmr->timeri); 329 return 0; 330 } 331 332 static int initialize_timer(struct snd_seq_timer *tmr) 333 { 334 struct snd_timer *t; 335 unsigned long freq; 336 337 t = tmr->timeri->timer; 338 if (snd_BUG_ON(!t)) 339 return -EINVAL; 340 341 freq = tmr->preferred_resolution; 342 if (!freq) 343 freq = DEFAULT_FREQUENCY; 344 else if (freq < MIN_FREQUENCY) 345 freq = MIN_FREQUENCY; 346 else if (freq > MAX_FREQUENCY) 347 freq = MAX_FREQUENCY; 348 349 tmr->ticks = 1; 350 if (!(t->hw.flags & SNDRV_TIMER_HW_SLAVE)) { 351 unsigned long r = t->hw.resolution; 352 if (! r && t->hw.c_resolution) 353 r = t->hw.c_resolution(t); 354 if (r) { 355 tmr->ticks = (unsigned int)(1000000000uL / (r * freq)); 356 if (! tmr->ticks) 357 tmr->ticks = 1; 358 } 359 } 360 tmr->initialized = 1; 361 return 0; 362 } 363 364 int snd_seq_timer_start(struct snd_seq_timer * tmr) 365 { 366 if (! tmr->timeri) 367 return -EINVAL; 368 if (tmr->running) 369 snd_seq_timer_stop(tmr); 370 snd_seq_timer_reset(tmr); 371 if (initialize_timer(tmr) < 0) 372 return -EINVAL; 373 snd_timer_start(tmr->timeri, tmr->ticks); 374 tmr->running = 1; 375 do_gettimeofday(&tmr->last_update); 376 return 0; 377 } 378 379 int snd_seq_timer_continue(struct snd_seq_timer * tmr) 380 { 381 if (! tmr->timeri) 382 return -EINVAL; 383 if (tmr->running) 384 return -EBUSY; 385 if (! tmr->initialized) { 386 snd_seq_timer_reset(tmr); 387 if (initialize_timer(tmr) < 0) 388 return -EINVAL; 389 } 390 snd_timer_start(tmr->timeri, tmr->ticks); 391 tmr->running = 1; 392 do_gettimeofday(&tmr->last_update); 393 return 0; 394 } 395 396 /* return current 'real' time. use timeofday() to get better granularity. */ 397 snd_seq_real_time_t snd_seq_timer_get_cur_time(struct snd_seq_timer *tmr) 398 { 399 snd_seq_real_time_t cur_time; 400 401 cur_time = tmr->cur_time; 402 if (tmr->running) { 403 struct timeval tm; 404 int usec; 405 do_gettimeofday(&tm); 406 usec = (int)(tm.tv_usec - tmr->last_update.tv_usec); 407 if (usec < 0) { 408 cur_time.tv_nsec += (1000000 + usec) * 1000; 409 cur_time.tv_sec += tm.tv_sec - tmr->last_update.tv_sec - 1; 410 } else { 411 cur_time.tv_nsec += usec * 1000; 412 cur_time.tv_sec += tm.tv_sec - tmr->last_update.tv_sec; 413 } 414 snd_seq_sanity_real_time(&cur_time); 415 } 416 417 return cur_time; 418 } 419 420 /* TODO: use interpolation on tick queue (will only be useful for very 421 high PPQ values) */ 422 snd_seq_tick_time_t snd_seq_timer_get_cur_tick(struct snd_seq_timer *tmr) 423 { 424 return tmr->tick.cur_tick; 425 } 426 427 428 #ifdef CONFIG_PROC_FS 429 /* exported to seq_info.c */ 430 void snd_seq_info_timer_read(struct snd_info_entry *entry, 431 struct snd_info_buffer *buffer) 432 { 433 int idx; 434 struct snd_seq_queue *q; 435 struct snd_seq_timer *tmr; 436 struct snd_timer_instance *ti; 437 unsigned long resolution; 438 439 for (idx = 0; idx < SNDRV_SEQ_MAX_QUEUES; idx++) { 440 q = queueptr(idx); 441 if (q == NULL) 442 continue; 443 if ((tmr = q->timer) == NULL || 444 (ti = tmr->timeri) == NULL) { 445 queuefree(q); 446 continue; 447 } 448 snd_iprintf(buffer, "Timer for queue %i : %s\n", q->queue, ti->timer->name); 449 resolution = snd_timer_resolution(ti) * tmr->ticks; 450 snd_iprintf(buffer, " Period time : %lu.%09lu\n", resolution / 1000000000, resolution % 1000000000); 451 snd_iprintf(buffer, " Skew : %u / %u\n", tmr->skew, tmr->skew_base); 452 queuefree(q); 453 } 454 } 455 #endif /* CONFIG_PROC_FS */ 456 457