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
snd_seq_timer_set_tick_resolution(struct snd_seq_timer * tmr)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) */
snd_seq_timer_new(void)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) */
snd_seq_timer_delete(struct snd_seq_timer ** tmr)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
snd_seq_timer_defaults(struct snd_seq_timer * tmr)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
snd_seq_timer_reset(struct snd_seq_timer * tmr)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 */
snd_seq_timer_interrupt(struct snd_timer_instance * timeri,unsigned long resolution,unsigned long ticks)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 */
snd_seq_timer_set_tempo(struct snd_seq_timer * tmr,int 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 */
snd_seq_timer_set_ppq(struct snd_seq_timer * tmr,int 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 */
snd_seq_timer_set_position_tick(struct snd_seq_timer * tmr,snd_seq_tick_time_t 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 */
snd_seq_timer_set_position_time(struct snd_seq_timer * tmr,snd_seq_real_time_t 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 */
snd_seq_timer_set_skew(struct snd_seq_timer * tmr,unsigned int skew,unsigned int base)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
snd_seq_timer_open(struct snd_seq_queue * q)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 if (err < 0) {
294 snd_printk(KERN_ERR "seq fatal error: cannot create timer (%i)\n", err);
295 return err;
296 }
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
snd_seq_timer_close(struct snd_seq_queue * q)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
snd_seq_timer_stop(struct snd_seq_timer * tmr)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
initialize_timer(struct snd_seq_timer * tmr)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
snd_seq_timer_start(struct snd_seq_timer * tmr)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
snd_seq_timer_continue(struct snd_seq_timer * tmr)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. */
snd_seq_timer_get_cur_time(struct snd_seq_timer * tmr)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) */
snd_seq_timer_get_cur_tick(struct snd_seq_timer * tmr)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 */
snd_seq_info_timer_read(struct snd_info_entry * entry,struct snd_info_buffer * buffer)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