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 snd_assert(tmr, 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->tick, tmr->tempo, tmr->ppq); 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 snd_assert(tmr, return -EINVAL); 194 if (ppq <= 0) 195 return -EINVAL; 196 spin_lock_irqsave(&tmr->lock, flags); 197 if (tmr->running && (ppq != tmr->ppq)) { 198 /* refuse to change ppq on running timers */ 199 /* because it will upset the song position (ticks) */ 200 spin_unlock_irqrestore(&tmr->lock, flags); 201 snd_printd("seq: cannot change ppq of a running timer\n"); 202 return -EBUSY; 203 } 204 205 tmr->ppq = ppq; 206 snd_seq_timer_set_tick_resolution(&tmr->tick, tmr->tempo, tmr->ppq); 207 spin_unlock_irqrestore(&tmr->lock, flags); 208 return 0; 209 } 210 211 /* set current tick position */ 212 int snd_seq_timer_set_position_tick(struct snd_seq_timer *tmr, 213 snd_seq_tick_time_t position) 214 { 215 unsigned long flags; 216 217 snd_assert(tmr, 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 snd_assert(tmr, return -EINVAL); 233 234 snd_seq_sanity_real_time(&position); 235 spin_lock_irqsave(&tmr->lock, flags); 236 tmr->cur_time = position; 237 spin_unlock_irqrestore(&tmr->lock, flags); 238 return 0; 239 } 240 241 /* set timer skew */ 242 int snd_seq_timer_set_skew(struct snd_seq_timer *tmr, unsigned int skew, 243 unsigned int base) 244 { 245 unsigned long flags; 246 247 snd_assert(tmr, return -EINVAL); 248 249 /* FIXME */ 250 if (base != SKEW_BASE) { 251 snd_printd("invalid skew base 0x%x\n", base); 252 return -EINVAL; 253 } 254 spin_lock_irqsave(&tmr->lock, flags); 255 tmr->skew = skew; 256 spin_unlock_irqrestore(&tmr->lock, flags); 257 return 0; 258 } 259 260 int snd_seq_timer_open(struct snd_seq_queue *q) 261 { 262 struct snd_timer_instance *t; 263 struct snd_seq_timer *tmr; 264 char str[32]; 265 int err; 266 267 tmr = q->timer; 268 snd_assert(tmr != NULL, return -EINVAL); 269 if (tmr->timeri) 270 return -EBUSY; 271 sprintf(str, "sequencer queue %i", q->queue); 272 if (tmr->type != SNDRV_SEQ_TIMER_ALSA) /* standard ALSA timer */ 273 return -EINVAL; 274 if (tmr->alsa_id.dev_class != SNDRV_TIMER_CLASS_SLAVE) 275 tmr->alsa_id.dev_sclass = SNDRV_TIMER_SCLASS_SEQUENCER; 276 err = snd_timer_open(&t, str, &tmr->alsa_id, q->queue); 277 if (err < 0 && tmr->alsa_id.dev_class != SNDRV_TIMER_CLASS_SLAVE) { 278 if (tmr->alsa_id.dev_class != SNDRV_TIMER_CLASS_GLOBAL || 279 tmr->alsa_id.device != SNDRV_TIMER_GLOBAL_SYSTEM) { 280 struct snd_timer_id tid; 281 memset(&tid, 0, sizeof(tid)); 282 tid.dev_class = SNDRV_TIMER_CLASS_GLOBAL; 283 tid.dev_sclass = SNDRV_TIMER_SCLASS_SEQUENCER; 284 tid.card = -1; 285 tid.device = SNDRV_TIMER_GLOBAL_SYSTEM; 286 err = snd_timer_open(&t, str, &tid, q->queue); 287 } 288 if (err < 0) { 289 snd_printk(KERN_ERR "seq fatal error: cannot create timer (%i)\n", err); 290 return err; 291 } 292 } 293 t->callback = snd_seq_timer_interrupt; 294 t->callback_data = q; 295 t->flags |= SNDRV_TIMER_IFLG_AUTO; 296 tmr->timeri = t; 297 return 0; 298 } 299 300 int snd_seq_timer_close(struct snd_seq_queue *q) 301 { 302 struct snd_seq_timer *tmr; 303 304 tmr = q->timer; 305 snd_assert(tmr != NULL, return -EINVAL); 306 if (tmr->timeri) { 307 snd_timer_stop(tmr->timeri); 308 snd_timer_close(tmr->timeri); 309 tmr->timeri = NULL; 310 } 311 return 0; 312 } 313 314 int snd_seq_timer_stop(struct snd_seq_timer * tmr) 315 { 316 if (! tmr->timeri) 317 return -EINVAL; 318 if (!tmr->running) 319 return 0; 320 tmr->running = 0; 321 snd_timer_pause(tmr->timeri); 322 return 0; 323 } 324 325 static int initialize_timer(struct snd_seq_timer *tmr) 326 { 327 struct snd_timer *t; 328 unsigned long freq; 329 330 t = tmr->timeri->timer; 331 snd_assert(t, return -EINVAL); 332 333 freq = tmr->preferred_resolution; 334 if (!freq) 335 freq = DEFAULT_FREQUENCY; 336 else if (freq < MIN_FREQUENCY) 337 freq = MIN_FREQUENCY; 338 else if (freq > MAX_FREQUENCY) 339 freq = MAX_FREQUENCY; 340 341 tmr->ticks = 1; 342 if (!(t->hw.flags & SNDRV_TIMER_HW_SLAVE)) { 343 unsigned long r = t->hw.resolution; 344 if (! r && t->hw.c_resolution) 345 r = t->hw.c_resolution(t); 346 if (r) { 347 tmr->ticks = (unsigned int)(1000000000uL / (r * freq)); 348 if (! tmr->ticks) 349 tmr->ticks = 1; 350 } 351 } 352 tmr->initialized = 1; 353 return 0; 354 } 355 356 int snd_seq_timer_start(struct snd_seq_timer * tmr) 357 { 358 if (! tmr->timeri) 359 return -EINVAL; 360 if (tmr->running) 361 snd_seq_timer_stop(tmr); 362 snd_seq_timer_reset(tmr); 363 if (initialize_timer(tmr) < 0) 364 return -EINVAL; 365 snd_timer_start(tmr->timeri, tmr->ticks); 366 tmr->running = 1; 367 do_gettimeofday(&tmr->last_update); 368 return 0; 369 } 370 371 int snd_seq_timer_continue(struct snd_seq_timer * tmr) 372 { 373 if (! tmr->timeri) 374 return -EINVAL; 375 if (tmr->running) 376 return -EBUSY; 377 if (! tmr->initialized) { 378 snd_seq_timer_reset(tmr); 379 if (initialize_timer(tmr) < 0) 380 return -EINVAL; 381 } 382 snd_timer_start(tmr->timeri, tmr->ticks); 383 tmr->running = 1; 384 do_gettimeofday(&tmr->last_update); 385 return 0; 386 } 387 388 /* return current 'real' time. use timeofday() to get better granularity. */ 389 snd_seq_real_time_t snd_seq_timer_get_cur_time(struct snd_seq_timer *tmr) 390 { 391 snd_seq_real_time_t cur_time; 392 393 cur_time = tmr->cur_time; 394 if (tmr->running) { 395 struct timeval tm; 396 int usec; 397 do_gettimeofday(&tm); 398 usec = (int)(tm.tv_usec - tmr->last_update.tv_usec); 399 if (usec < 0) { 400 cur_time.tv_nsec += (1000000 + usec) * 1000; 401 cur_time.tv_sec += tm.tv_sec - tmr->last_update.tv_sec - 1; 402 } else { 403 cur_time.tv_nsec += usec * 1000; 404 cur_time.tv_sec += tm.tv_sec - tmr->last_update.tv_sec; 405 } 406 snd_seq_sanity_real_time(&cur_time); 407 } 408 409 return cur_time; 410 } 411 412 /* TODO: use interpolation on tick queue (will only be useful for very 413 high PPQ values) */ 414 snd_seq_tick_time_t snd_seq_timer_get_cur_tick(struct snd_seq_timer *tmr) 415 { 416 return tmr->tick.cur_tick; 417 } 418 419 420 #ifdef CONFIG_PROC_FS 421 /* exported to seq_info.c */ 422 void snd_seq_info_timer_read(struct snd_info_entry *entry, 423 struct snd_info_buffer *buffer) 424 { 425 int idx; 426 struct snd_seq_queue *q; 427 struct snd_seq_timer *tmr; 428 struct snd_timer_instance *ti; 429 unsigned long resolution; 430 431 for (idx = 0; idx < SNDRV_SEQ_MAX_QUEUES; idx++) { 432 q = queueptr(idx); 433 if (q == NULL) 434 continue; 435 if ((tmr = q->timer) == NULL || 436 (ti = tmr->timeri) == NULL) { 437 queuefree(q); 438 continue; 439 } 440 snd_iprintf(buffer, "Timer for queue %i : %s\n", q->queue, ti->timer->name); 441 resolution = snd_timer_resolution(ti) * tmr->ticks; 442 snd_iprintf(buffer, " Period time : %lu.%09lu\n", resolution / 1000000000, resolution % 1000000000); 443 snd_iprintf(buffer, " Skew : %u / %u\n", tmr->skew, tmr->skew_base); 444 queuefree(q); 445 } 446 } 447 #endif /* CONFIG_PROC_FS */ 448 449