xref: /openbmc/linux/sound/isa/sb/emu8000_pcm.c (revision 1da177e4)
1 /*
2  * pcm emulation on emu8000 wavetable
3  *
4  *  Copyright (C) 2002 Takashi Iwai <tiwai@suse.de>
5  *
6  *   This program is free software; you can redistribute it and/or modify
7  *   it under the terms of the GNU General Public License as published by
8  *   the Free Software Foundation; either version 2 of the License, or
9  *   (at your option) any later version.
10  *
11  *   This program is distributed in the hope that it will be useful,
12  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
13  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  *   GNU General Public License for more details.
15  *
16  *   You should have received a copy of the GNU General Public License
17  *   along with this program; if not, write to the Free Software
18  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
19  */
20 
21 #include "emu8000_local.h"
22 #include <linux/init.h>
23 #include <sound/initval.h>
24 #include <sound/pcm.h>
25 
26 /*
27  * define the following if you want to use this pcm with non-interleaved mode
28  */
29 /* #define USE_NONINTERLEAVE */
30 
31 /* NOTE: for using the non-interleaved mode with alsa-lib, you have to set
32  * mmap_emulation flag to 1 in your .asoundrc, such like
33  *
34  *	pcm.emu8k {
35  *		type plug
36  *		slave.pcm {
37  *			type hw
38  *			card 0
39  *			device 1
40  *			mmap_emulation 1
41  *		}
42  *	}
43  *
44  * besides, for the time being, the non-interleaved mode doesn't work well on
45  * alsa-lib...
46  */
47 
48 
49 typedef struct snd_emu8k_pcm emu8k_pcm_t;
50 
51 struct snd_emu8k_pcm {
52 	emu8000_t *emu;
53 	snd_pcm_substream_t *substream;
54 
55 	unsigned int allocated_bytes;
56 	snd_util_memblk_t *block;
57 	unsigned int offset;
58 	unsigned int buf_size;
59 	unsigned int period_size;
60 	unsigned int loop_start[2];
61 	unsigned int pitch;
62 	int panning[2];
63 	int last_ptr;
64 	int period_pos;
65 	int voices;
66 	unsigned int dram_opened: 1;
67 	unsigned int running: 1;
68 	unsigned int timer_running: 1;
69 	struct timer_list timer;
70 	spinlock_t timer_lock;
71 };
72 
73 #define LOOP_BLANK_SIZE		8
74 
75 
76 /*
77  * open up channels for the simultaneous data transfer and playback
78  */
79 static int
80 emu8k_open_dram_for_pcm(emu8000_t *emu, int channels)
81 {
82 	int i;
83 
84 	/* reserve up to 2 voices for playback */
85 	snd_emux_lock_voice(emu->emu, 0);
86 	if (channels > 1)
87 		snd_emux_lock_voice(emu->emu, 1);
88 
89 	/* reserve 28 voices for loading */
90 	for (i = channels + 1; i < EMU8000_DRAM_VOICES; i++) {
91 		unsigned int mode = EMU8000_RAM_WRITE;
92 		snd_emux_lock_voice(emu->emu, i);
93 #ifndef USE_NONINTERLEAVE
94 		if (channels > 1 && (i & 1) != 0)
95 			mode |= EMU8000_RAM_RIGHT;
96 #endif
97 		snd_emu8000_dma_chan(emu, i, mode);
98 	}
99 
100 	/* assign voice 31 and 32 to ROM */
101 	EMU8000_VTFT_WRITE(emu, 30, 0);
102 	EMU8000_PSST_WRITE(emu, 30, 0x1d8);
103 	EMU8000_CSL_WRITE(emu, 30, 0x1e0);
104 	EMU8000_CCCA_WRITE(emu, 30, 0x1d8);
105 	EMU8000_VTFT_WRITE(emu, 31, 0);
106 	EMU8000_PSST_WRITE(emu, 31, 0x1d8);
107 	EMU8000_CSL_WRITE(emu, 31, 0x1e0);
108 	EMU8000_CCCA_WRITE(emu, 31, 0x1d8);
109 
110 	return 0;
111 }
112 
113 /*
114  */
115 static void
116 snd_emu8000_write_wait(emu8000_t *emu, int can_schedule)
117 {
118 	while ((EMU8000_SMALW_READ(emu) & 0x80000000) != 0) {
119 		if (can_schedule) {
120 			set_current_state(TASK_INTERRUPTIBLE);
121 			schedule_timeout(1);
122 			if (signal_pending(current))
123 				break;
124 		}
125 	}
126 }
127 
128 /*
129  * close all channels
130  */
131 static void
132 emu8k_close_dram(emu8000_t *emu)
133 {
134 	int i;
135 
136 	for (i = 0; i < 2; i++)
137 		snd_emux_unlock_voice(emu->emu, i);
138 	for (; i < EMU8000_DRAM_VOICES; i++) {
139 		snd_emu8000_dma_chan(emu, i, EMU8000_RAM_CLOSE);
140 		snd_emux_unlock_voice(emu->emu, i);
141 	}
142 }
143 
144 /*
145  * convert Hz to AWE32 rate offset (see emux/soundfont.c)
146  */
147 
148 #define OFFSET_SAMPLERATE	1011119		/* base = 44100 */
149 #define SAMPLERATE_RATIO	4096
150 
151 static int calc_rate_offset(int hz)
152 {
153 	return snd_sf_linear_to_log(hz, OFFSET_SAMPLERATE, SAMPLERATE_RATIO);
154 }
155 
156 
157 /*
158  */
159 
160 static snd_pcm_hardware_t emu8k_pcm_hw = {
161 #ifdef USE_NONINTERLEAVE
162 	.info =			SNDRV_PCM_INFO_NONINTERLEAVED,
163 #else
164 	.info =			SNDRV_PCM_INFO_INTERLEAVED,
165 #endif
166 	.formats =		SNDRV_PCM_FMTBIT_S16_LE,
167 	.rates =		SNDRV_PCM_RATE_CONTINUOUS | SNDRV_PCM_RATE_8000_48000,
168 	.rate_min =		4000,
169 	.rate_max =		48000,
170 	.channels_min =		1,
171 	.channels_max =		2,
172 	.buffer_bytes_max =	(128*1024),
173 	.period_bytes_min =	1024,
174 	.period_bytes_max =	(128*1024),
175 	.periods_min =		2,
176 	.periods_max =		1024,
177 	.fifo_size =		0,
178 
179 };
180 
181 /*
182  * get the current position at the given channel from CCCA register
183  */
184 static inline int emu8k_get_curpos(emu8k_pcm_t *rec, int ch)
185 {
186 	int val = EMU8000_CCCA_READ(rec->emu, ch) & 0xfffffff;
187 	val -= rec->loop_start[ch] - 1;
188 	return val;
189 }
190 
191 
192 /*
193  * timer interrupt handler
194  * check the current position and update the period if necessary.
195  */
196 static void emu8k_pcm_timer_func(unsigned long data)
197 {
198 	emu8k_pcm_t *rec = (emu8k_pcm_t *)data;
199 	int ptr, delta;
200 
201 	spin_lock(&rec->timer_lock);
202 	/* update the current pointer */
203 	ptr = emu8k_get_curpos(rec, 0);
204 	if (ptr < rec->last_ptr)
205 		delta = ptr + rec->buf_size - rec->last_ptr;
206 	else
207 		delta = ptr - rec->last_ptr;
208 	rec->period_pos += delta;
209 	rec->last_ptr = ptr;
210 
211 	/* reprogram timer */
212 	rec->timer.expires = jiffies + 1;
213 	add_timer(&rec->timer);
214 
215 	/* update period */
216 	if (rec->period_pos >= (int)rec->period_size) {
217 		rec->period_pos %= rec->period_size;
218 		spin_unlock(&rec->timer_lock);
219 		snd_pcm_period_elapsed(rec->substream);
220 		return;
221 	}
222 	spin_unlock(&rec->timer_lock);
223 }
224 
225 
226 /*
227  * open pcm
228  * creating an instance here
229  */
230 static int emu8k_pcm_open(snd_pcm_substream_t *subs)
231 {
232 	emu8000_t *emu = snd_pcm_substream_chip(subs);
233 	emu8k_pcm_t *rec;
234 	snd_pcm_runtime_t *runtime = subs->runtime;
235 
236 	rec = kcalloc(1, sizeof(*rec), GFP_KERNEL);
237 	if (! rec)
238 		return -ENOMEM;
239 
240 	rec->emu = emu;
241 	rec->substream = subs;
242 	runtime->private_data = rec;
243 
244 	spin_lock_init(&rec->timer_lock);
245 	init_timer(&rec->timer);
246 	rec->timer.function = emu8k_pcm_timer_func;
247 	rec->timer.data = (unsigned long)rec;
248 
249 	runtime->hw = emu8k_pcm_hw;
250 	runtime->hw.buffer_bytes_max = emu->mem_size - LOOP_BLANK_SIZE * 3;
251 	runtime->hw.period_bytes_max = runtime->hw.buffer_bytes_max / 2;
252 
253 	/* use timer to update periods.. (specified in msec) */
254 	snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_PERIOD_TIME,
255 				     (1000000 + HZ - 1) / HZ, UINT_MAX);
256 
257 	return 0;
258 }
259 
260 static int emu8k_pcm_close(snd_pcm_substream_t *subs)
261 {
262 	emu8k_pcm_t *rec = subs->runtime->private_data;
263 	kfree(rec);
264 	subs->runtime->private_data = NULL;
265 	return 0;
266 }
267 
268 /*
269  * calculate pitch target
270  */
271 static int calc_pitch_target(int pitch)
272 {
273 	int ptarget = 1 << (pitch >> 12);
274 	if (pitch & 0x800) ptarget += (ptarget * 0x102e) / 0x2710;
275 	if (pitch & 0x400) ptarget += (ptarget * 0x764) / 0x2710;
276 	if (pitch & 0x200) ptarget += (ptarget * 0x389) / 0x2710;
277 	ptarget += (ptarget >> 1);
278 	if (ptarget > 0xffff) ptarget = 0xffff;
279 	return ptarget;
280 }
281 
282 /*
283  * set up the voice
284  */
285 static void setup_voice(emu8k_pcm_t *rec, int ch)
286 {
287 	emu8000_t *hw = rec->emu;
288 	unsigned int temp;
289 
290 	/* channel to be silent and idle */
291 	EMU8000_DCYSUSV_WRITE(hw, ch, 0x0080);
292 	EMU8000_VTFT_WRITE(hw, ch, 0x0000FFFF);
293 	EMU8000_CVCF_WRITE(hw, ch, 0x0000FFFF);
294 	EMU8000_PTRX_WRITE(hw, ch, 0);
295 	EMU8000_CPF_WRITE(hw, ch, 0);
296 
297 	/* pitch offset */
298 	EMU8000_IP_WRITE(hw, ch, rec->pitch);
299 	/* set envelope parameters */
300 	EMU8000_ENVVAL_WRITE(hw, ch, 0x8000);
301 	EMU8000_ATKHLD_WRITE(hw, ch, 0x7f7f);
302 	EMU8000_DCYSUS_WRITE(hw, ch, 0x7f7f);
303 	EMU8000_ENVVOL_WRITE(hw, ch, 0x8000);
304 	EMU8000_ATKHLDV_WRITE(hw, ch, 0x7f7f);
305 	/* decay/sustain parameter for volume envelope is used
306 	   for triggerg the voice */
307 	/* modulation envelope heights */
308 	EMU8000_PEFE_WRITE(hw, ch, 0x0);
309 	/* lfo1/2 delay */
310 	EMU8000_LFO1VAL_WRITE(hw, ch, 0x8000);
311 	EMU8000_LFO2VAL_WRITE(hw, ch, 0x8000);
312 	/* lfo1 pitch & cutoff shift */
313 	EMU8000_FMMOD_WRITE(hw, ch, 0);
314 	/* lfo1 volume & freq */
315 	EMU8000_TREMFRQ_WRITE(hw, ch, 0);
316 	/* lfo2 pitch & freq */
317 	EMU8000_FM2FRQ2_WRITE(hw, ch, 0);
318 	/* pan & loop start */
319 	temp = rec->panning[ch];
320 	temp = (temp <<24) | ((unsigned int)rec->loop_start[ch] - 1);
321 	EMU8000_PSST_WRITE(hw, ch, temp);
322 	/* chorus & loop end (chorus 8bit, MSB) */
323 	temp = 0; // chorus
324 	temp = (temp << 24) | ((unsigned int)rec->loop_start[ch] + rec->buf_size - 1);
325 	EMU8000_CSL_WRITE(hw, ch, temp);
326 	/* Q & current address (Q 4bit value, MSB) */
327 	temp = 0; // filterQ
328 	temp = (temp << 28) | ((unsigned int)rec->loop_start[ch] - 1);
329 	EMU8000_CCCA_WRITE(hw, ch, temp);
330 	/* clear unknown registers */
331 	EMU8000_00A0_WRITE(hw, ch, 0);
332 	EMU8000_0080_WRITE(hw, ch, 0);
333 }
334 
335 /*
336  * trigger the voice
337  */
338 static void start_voice(emu8k_pcm_t *rec, int ch)
339 {
340 	unsigned long flags;
341 	emu8000_t *hw = rec->emu;
342 	unsigned int temp, aux;
343 	int pt = calc_pitch_target(rec->pitch);
344 
345 	/* cutoff and volume */
346 	EMU8000_IFATN_WRITE(hw, ch, 0xff00);
347 	EMU8000_VTFT_WRITE(hw, ch, 0xffff);
348 	EMU8000_CVCF_WRITE(hw, ch, 0xffff);
349 	/* trigger envelope */
350 	EMU8000_DCYSUSV_WRITE(hw, ch, 0x7f7f);
351 	/* set reverb and pitch target */
352 	temp = 0; // reverb
353 	if (rec->panning[ch] == 0)
354 		aux = 0xff;
355 	else
356 		aux = (-rec->panning[ch]) & 0xff;
357 	temp = (temp << 8) | (pt << 16) | aux;
358 	EMU8000_PTRX_WRITE(hw, ch, temp);
359 	EMU8000_CPF_WRITE(hw, ch, pt << 16);
360 
361 	/* start timer */
362 	spin_lock_irqsave(&rec->timer_lock, flags);
363 	if (! rec->timer_running) {
364 		rec->timer.expires = jiffies + 1;
365 		add_timer(&rec->timer);
366 		rec->timer_running = 1;
367 	}
368 	spin_unlock_irqrestore(&rec->timer_lock, flags);
369 }
370 
371 /*
372  * stop the voice immediately
373  */
374 static void stop_voice(emu8k_pcm_t *rec, int ch)
375 {
376 	unsigned long flags;
377 	emu8000_t *hw = rec->emu;
378 
379 	EMU8000_DCYSUSV_WRITE(hw, ch, 0x807F);
380 
381 	/* stop timer */
382 	spin_lock_irqsave(&rec->timer_lock, flags);
383 	if (rec->timer_running) {
384 		del_timer(&rec->timer);
385 		rec->timer_running = 0;
386 	}
387 	spin_unlock_irqrestore(&rec->timer_lock, flags);
388 }
389 
390 static int emu8k_pcm_trigger(snd_pcm_substream_t *subs, int cmd)
391 {
392 	emu8k_pcm_t *rec = subs->runtime->private_data;
393 	int ch;
394 
395 	switch (cmd) {
396 	case SNDRV_PCM_TRIGGER_START:
397 		for (ch = 0; ch < rec->voices; ch++)
398 			start_voice(rec, ch);
399 		rec->running = 1;
400 		break;
401 	case SNDRV_PCM_TRIGGER_STOP:
402 		rec->running = 0;
403 		for (ch = 0; ch < rec->voices; ch++)
404 			stop_voice(rec, ch);
405 		break;
406 	default:
407 		return -EINVAL;
408 	}
409 	return 0;
410 }
411 
412 
413 /*
414  * copy / silence ops
415  */
416 
417 /*
418  * this macro should be inserted in the copy/silence loops
419  * to reduce the latency.  without this, the system will hang up
420  * during the whole loop.
421  */
422 #define CHECK_SCHEDULER() \
423 do { \
424 	cond_resched();\
425 	if (signal_pending(current))\
426 		return -EAGAIN;\
427 } while (0)
428 
429 
430 #ifdef USE_NONINTERLEAVE
431 /* copy one channel block */
432 static int emu8k_transfer_block(emu8000_t *emu, int offset, unsigned short *buf, int count)
433 {
434 	EMU8000_SMALW_WRITE(emu, offset);
435 	while (count > 0) {
436 		unsigned short sval;
437 		CHECK_SCHEDULER();
438 		get_user(sval, buf);
439 		EMU8000_SMLD_WRITE(emu, sval);
440 		buf++;
441 		count--;
442 	}
443 	return 0;
444 }
445 
446 static int emu8k_pcm_copy(snd_pcm_substream_t *subs,
447 			  int voice,
448 			  snd_pcm_uframes_t pos,
449 			  void *src,
450 			  snd_pcm_uframes_t count)
451 {
452 	emu8k_pcm_t *rec = subs->runtime->private_data;
453 	emu8000_t *emu = rec->emu;
454 
455 	snd_emu8000_write_wait(emu, 1);
456 	if (voice == -1) {
457 		unsigned short *buf = src;
458 		int i, err;
459 		count /= rec->voices;
460 		for (i = 0; i < rec->voices; i++) {
461 			err = emu8k_transfer_block(emu, pos + rec->loop_start[i], buf, count);
462 			if (err < 0)
463 				return err;
464 			buf += count;
465 		}
466 		return 0;
467 	} else {
468 		return emu8k_transfer_block(emu, pos + rec->loop_start[voice], src, count);
469 	}
470 }
471 
472 /* make a channel block silence */
473 static int emu8k_silence_block(emu8000_t *emu, int offset, int count)
474 {
475 	EMU8000_SMALW_WRITE(emu, offset);
476 	while (count > 0) {
477 		CHECK_SCHEDULER();
478 		EMU8000_SMLD_WRITE(emu, 0);
479 		count--;
480 	}
481 	return 0;
482 }
483 
484 static int emu8k_pcm_silence(snd_pcm_substream_t *subs,
485 			     int voice,
486 			     snd_pcm_uframes_t pos,
487 			     snd_pcm_uframes_t count)
488 {
489 	emu8k_pcm_t *rec = subs->runtime->private_data;
490 	emu8000_t *emu = rec->emu;
491 
492 	snd_emu8000_write_wait(emu, 1);
493 	if (voice == -1 && rec->voices == 1)
494 		voice = 0;
495 	if (voice == -1) {
496 		int err;
497 		err = emu8k_silence_block(emu, pos + rec->loop_start[0], count / 2);
498 		if (err < 0)
499 			return err;
500 		return emu8k_silence_block(emu, pos + rec->loop_start[1], count / 2);
501 	} else {
502 		return emu8k_silence_block(emu, pos + rec->loop_start[voice], count);
503 	}
504 }
505 
506 #else /* interleave */
507 
508 /*
509  * copy the interleaved data can be done easily by using
510  * DMA "left" and "right" channels on emu8k engine.
511  */
512 static int emu8k_pcm_copy(snd_pcm_substream_t *subs,
513 			  int voice,
514 			  snd_pcm_uframes_t pos,
515 			  void __user *src,
516 			  snd_pcm_uframes_t count)
517 {
518 	emu8k_pcm_t *rec = subs->runtime->private_data;
519 	emu8000_t *emu = rec->emu;
520 	unsigned short __user *buf = src;
521 
522 	snd_emu8000_write_wait(emu, 1);
523 	EMU8000_SMALW_WRITE(emu, pos + rec->loop_start[0]);
524 	if (rec->voices > 1)
525 		EMU8000_SMARW_WRITE(emu, pos + rec->loop_start[1]);
526 
527 	while (count-- > 0) {
528 		unsigned short sval;
529 		CHECK_SCHEDULER();
530 		get_user(sval, buf);
531 		EMU8000_SMLD_WRITE(emu, sval);
532 		buf++;
533 		if (rec->voices > 1) {
534 			CHECK_SCHEDULER();
535 			get_user(sval, buf);
536 			EMU8000_SMRD_WRITE(emu, sval);
537 			buf++;
538 		}
539 	}
540 	return 0;
541 }
542 
543 static int emu8k_pcm_silence(snd_pcm_substream_t *subs,
544 			     int voice,
545 			     snd_pcm_uframes_t pos,
546 			     snd_pcm_uframes_t count)
547 {
548 	emu8k_pcm_t *rec = subs->runtime->private_data;
549 	emu8000_t *emu = rec->emu;
550 
551 	snd_emu8000_write_wait(emu, 1);
552 	EMU8000_SMALW_WRITE(emu, rec->loop_start[0] + pos);
553 	if (rec->voices > 1)
554 		EMU8000_SMARW_WRITE(emu, rec->loop_start[1] + pos);
555 	while (count-- > 0) {
556 		CHECK_SCHEDULER();
557 		EMU8000_SMLD_WRITE(emu, 0);
558 		if (rec->voices > 1) {
559 			CHECK_SCHEDULER();
560 			EMU8000_SMRD_WRITE(emu, 0);
561 		}
562 	}
563 	return 0;
564 }
565 #endif
566 
567 
568 /*
569  * allocate a memory block
570  */
571 static int emu8k_pcm_hw_params(snd_pcm_substream_t *subs,
572 			       snd_pcm_hw_params_t *hw_params)
573 {
574 	emu8k_pcm_t *rec = subs->runtime->private_data;
575 
576 	if (rec->block) {
577 		/* reallocation - release the old block */
578 		snd_util_mem_free(rec->emu->memhdr, rec->block);
579 		rec->block = NULL;
580 	}
581 
582 	rec->allocated_bytes = params_buffer_bytes(hw_params) + LOOP_BLANK_SIZE * 4;
583 	rec->block = snd_util_mem_alloc(rec->emu->memhdr, rec->allocated_bytes);
584 	if (! rec->block)
585 		return -ENOMEM;
586 	rec->offset = EMU8000_DRAM_OFFSET + (rec->block->offset >> 1); /* in word */
587 	/* at least dma_bytes must be set for non-interleaved mode */
588 	subs->dma_buffer.bytes = params_buffer_bytes(hw_params);
589 
590 	return 0;
591 }
592 
593 /*
594  * free the memory block
595  */
596 static int emu8k_pcm_hw_free(snd_pcm_substream_t *subs)
597 {
598 	emu8k_pcm_t *rec = subs->runtime->private_data;
599 
600 	if (rec->block) {
601 		int ch;
602 		for (ch = 0; ch < rec->voices; ch++)
603 			stop_voice(rec, ch); // to be sure
604 		if (rec->dram_opened)
605 			emu8k_close_dram(rec->emu);
606 		snd_util_mem_free(rec->emu->memhdr, rec->block);
607 		rec->block = NULL;
608 	}
609 	return 0;
610 }
611 
612 /*
613  */
614 static int emu8k_pcm_prepare(snd_pcm_substream_t *subs)
615 {
616 	emu8k_pcm_t *rec = subs->runtime->private_data;
617 
618 	rec->pitch = 0xe000 + calc_rate_offset(subs->runtime->rate);
619 	rec->last_ptr = 0;
620 	rec->period_pos = 0;
621 
622 	rec->buf_size = subs->runtime->buffer_size;
623 	rec->period_size = subs->runtime->period_size;
624 	rec->voices = subs->runtime->channels;
625 	rec->loop_start[0] = rec->offset + LOOP_BLANK_SIZE;
626 	if (rec->voices > 1)
627 		rec->loop_start[1] = rec->loop_start[0] + rec->buf_size + LOOP_BLANK_SIZE;
628 	if (rec->voices > 1) {
629 		rec->panning[0] = 0xff;
630 		rec->panning[1] = 0x00;
631 	} else
632 		rec->panning[0] = 0x80;
633 
634 	if (! rec->dram_opened) {
635 		int err, i, ch;
636 
637 		snd_emux_terminate_all(rec->emu->emu);
638 		if ((err = emu8k_open_dram_for_pcm(rec->emu, rec->voices)) != 0)
639 			return err;
640 		rec->dram_opened = 1;
641 
642 		/* clear loop blanks */
643 		snd_emu8000_write_wait(rec->emu, 0);
644 		EMU8000_SMALW_WRITE(rec->emu, rec->offset);
645 		for (i = 0; i < LOOP_BLANK_SIZE; i++)
646 			EMU8000_SMLD_WRITE(rec->emu, 0);
647 		for (ch = 0; ch < rec->voices; ch++) {
648 			EMU8000_SMALW_WRITE(rec->emu, rec->loop_start[ch] + rec->buf_size);
649 			for (i = 0; i < LOOP_BLANK_SIZE; i++)
650 				EMU8000_SMLD_WRITE(rec->emu, 0);
651 		}
652 	}
653 
654 	setup_voice(rec, 0);
655 	if (rec->voices > 1)
656 		setup_voice(rec, 1);
657 	return 0;
658 }
659 
660 static snd_pcm_uframes_t emu8k_pcm_pointer(snd_pcm_substream_t *subs)
661 {
662 	emu8k_pcm_t *rec = subs->runtime->private_data;
663 	if (rec->running)
664 		return emu8k_get_curpos(rec, 0);
665 	return 0;
666 }
667 
668 
669 static snd_pcm_ops_t emu8k_pcm_ops = {
670 	.open =		emu8k_pcm_open,
671 	.close =	emu8k_pcm_close,
672 	.ioctl =	snd_pcm_lib_ioctl,
673 	.hw_params =	emu8k_pcm_hw_params,
674 	.hw_free =	emu8k_pcm_hw_free,
675 	.prepare =	emu8k_pcm_prepare,
676 	.trigger =	emu8k_pcm_trigger,
677 	.pointer =	emu8k_pcm_pointer,
678 	.copy =		emu8k_pcm_copy,
679 	.silence =	emu8k_pcm_silence,
680 };
681 
682 
683 static void snd_emu8000_pcm_free(snd_pcm_t *pcm)
684 {
685 	emu8000_t *emu = pcm->private_data;
686 	emu->pcm = NULL;
687 }
688 
689 int snd_emu8000_pcm_new(snd_card_t *card, emu8000_t *emu, int index)
690 {
691 	snd_pcm_t *pcm;
692 	int err;
693 
694 	if ((err = snd_pcm_new(card, "Emu8000 PCM", index, 1, 0, &pcm)) < 0)
695 		return err;
696 	pcm->private_data = emu;
697 	pcm->private_free = snd_emu8000_pcm_free;
698 	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &emu8k_pcm_ops);
699 	emu->pcm = pcm;
700 
701 	snd_device_register(card, pcm);
702 
703 	return 0;
704 }
705