1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * pcm emulation on emu8000 wavetable
4 *
5 * Copyright (C) 2002 Takashi Iwai <tiwai@suse.de>
6 */
7
8 #include "emu8000_local.h"
9
10 #include <linux/sched/signal.h>
11 #include <linux/init.h>
12 #include <linux/slab.h>
13 #include <sound/initval.h>
14 #include <sound/pcm.h>
15
16 /*
17 * define the following if you want to use this pcm with non-interleaved mode
18 */
19 /* #define USE_NONINTERLEAVE */
20
21 /* NOTE: for using the non-interleaved mode with alsa-lib, you have to set
22 * mmap_emulation flag to 1 in your .asoundrc, such like
23 *
24 * pcm.emu8k {
25 * type plug
26 * slave.pcm {
27 * type hw
28 * card 0
29 * device 1
30 * mmap_emulation 1
31 * }
32 * }
33 *
34 * besides, for the time being, the non-interleaved mode doesn't work well on
35 * alsa-lib...
36 */
37
38
39 struct snd_emu8k_pcm {
40 struct snd_emu8000 *emu;
41 struct snd_pcm_substream *substream;
42
43 unsigned int allocated_bytes;
44 struct snd_util_memblk *block;
45 unsigned int offset;
46 unsigned int buf_size;
47 unsigned int period_size;
48 unsigned int loop_start[2];
49 unsigned int pitch;
50 int panning[2];
51 int last_ptr;
52 int period_pos;
53 int voices;
54 unsigned int dram_opened: 1;
55 unsigned int running: 1;
56 unsigned int timer_running: 1;
57 struct timer_list timer;
58 spinlock_t timer_lock;
59 };
60
61 #define LOOP_BLANK_SIZE 8
62
63
64 /*
65 * open up channels for the simultaneous data transfer and playback
66 */
67 static int
emu8k_open_dram_for_pcm(struct snd_emu8000 * emu,int channels)68 emu8k_open_dram_for_pcm(struct snd_emu8000 *emu, int channels)
69 {
70 int i;
71
72 /* reserve up to 2 voices for playback */
73 snd_emux_lock_voice(emu->emu, 0);
74 if (channels > 1)
75 snd_emux_lock_voice(emu->emu, 1);
76
77 /* reserve 28 voices for loading */
78 for (i = channels + 1; i < EMU8000_DRAM_VOICES; i++) {
79 unsigned int mode = EMU8000_RAM_WRITE;
80 snd_emux_lock_voice(emu->emu, i);
81 #ifndef USE_NONINTERLEAVE
82 if (channels > 1 && (i & 1) != 0)
83 mode |= EMU8000_RAM_RIGHT;
84 #endif
85 snd_emu8000_dma_chan(emu, i, mode);
86 }
87
88 /* assign voice 31 and 32 to ROM */
89 EMU8000_VTFT_WRITE(emu, 30, 0);
90 EMU8000_PSST_WRITE(emu, 30, 0x1d8);
91 EMU8000_CSL_WRITE(emu, 30, 0x1e0);
92 EMU8000_CCCA_WRITE(emu, 30, 0x1d8);
93 EMU8000_VTFT_WRITE(emu, 31, 0);
94 EMU8000_PSST_WRITE(emu, 31, 0x1d8);
95 EMU8000_CSL_WRITE(emu, 31, 0x1e0);
96 EMU8000_CCCA_WRITE(emu, 31, 0x1d8);
97
98 return 0;
99 }
100
101 /*
102 */
103 static void
snd_emu8000_write_wait(struct snd_emu8000 * emu,int can_schedule)104 snd_emu8000_write_wait(struct snd_emu8000 *emu, int can_schedule)
105 {
106 while ((EMU8000_SMALW_READ(emu) & 0x80000000) != 0) {
107 if (can_schedule) {
108 schedule_timeout_interruptible(1);
109 if (signal_pending(current))
110 break;
111 }
112 }
113 }
114
115 /*
116 * close all channels
117 */
118 static void
emu8k_close_dram(struct snd_emu8000 * emu)119 emu8k_close_dram(struct snd_emu8000 *emu)
120 {
121 int i;
122
123 for (i = 0; i < 2; i++)
124 snd_emux_unlock_voice(emu->emu, i);
125 for (; i < EMU8000_DRAM_VOICES; i++) {
126 snd_emu8000_dma_chan(emu, i, EMU8000_RAM_CLOSE);
127 snd_emux_unlock_voice(emu->emu, i);
128 }
129 }
130
131 /*
132 * convert Hz to AWE32 rate offset (see emux/soundfont.c)
133 */
134
135 #define OFFSET_SAMPLERATE 1011119 /* base = 44100 */
136 #define SAMPLERATE_RATIO 4096
137
calc_rate_offset(int hz)138 static int calc_rate_offset(int hz)
139 {
140 return snd_sf_linear_to_log(hz, OFFSET_SAMPLERATE, SAMPLERATE_RATIO);
141 }
142
143
144 /*
145 */
146
147 static const struct snd_pcm_hardware emu8k_pcm_hw = {
148 #ifdef USE_NONINTERLEAVE
149 .info = SNDRV_PCM_INFO_NONINTERLEAVED,
150 #else
151 .info = SNDRV_PCM_INFO_INTERLEAVED,
152 #endif
153 .formats = SNDRV_PCM_FMTBIT_S16_LE,
154 .rates = SNDRV_PCM_RATE_CONTINUOUS | SNDRV_PCM_RATE_8000_48000,
155 .rate_min = 4000,
156 .rate_max = 48000,
157 .channels_min = 1,
158 .channels_max = 2,
159 .buffer_bytes_max = (128*1024),
160 .period_bytes_min = 1024,
161 .period_bytes_max = (128*1024),
162 .periods_min = 2,
163 .periods_max = 1024,
164 .fifo_size = 0,
165
166 };
167
168 /*
169 * get the current position at the given channel from CCCA register
170 */
emu8k_get_curpos(struct snd_emu8k_pcm * rec,int ch)171 static inline int emu8k_get_curpos(struct snd_emu8k_pcm *rec, int ch)
172 {
173 int val = EMU8000_CCCA_READ(rec->emu, ch) & 0xfffffff;
174 val -= rec->loop_start[ch] - 1;
175 return val;
176 }
177
178
179 /*
180 * timer interrupt handler
181 * check the current position and update the period if necessary.
182 */
emu8k_pcm_timer_func(struct timer_list * t)183 static void emu8k_pcm_timer_func(struct timer_list *t)
184 {
185 struct snd_emu8k_pcm *rec = from_timer(rec, t, timer);
186 int ptr, delta;
187
188 spin_lock(&rec->timer_lock);
189 /* update the current pointer */
190 ptr = emu8k_get_curpos(rec, 0);
191 if (ptr < rec->last_ptr)
192 delta = ptr + rec->buf_size - rec->last_ptr;
193 else
194 delta = ptr - rec->last_ptr;
195 rec->period_pos += delta;
196 rec->last_ptr = ptr;
197
198 /* reprogram timer */
199 mod_timer(&rec->timer, jiffies + 1);
200
201 /* update period */
202 if (rec->period_pos >= (int)rec->period_size) {
203 rec->period_pos %= rec->period_size;
204 spin_unlock(&rec->timer_lock);
205 snd_pcm_period_elapsed(rec->substream);
206 return;
207 }
208 spin_unlock(&rec->timer_lock);
209 }
210
211
212 /*
213 * open pcm
214 * creating an instance here
215 */
emu8k_pcm_open(struct snd_pcm_substream * subs)216 static int emu8k_pcm_open(struct snd_pcm_substream *subs)
217 {
218 struct snd_emu8000 *emu = snd_pcm_substream_chip(subs);
219 struct snd_emu8k_pcm *rec;
220 struct snd_pcm_runtime *runtime = subs->runtime;
221
222 rec = kzalloc(sizeof(*rec), GFP_KERNEL);
223 if (! rec)
224 return -ENOMEM;
225
226 rec->emu = emu;
227 rec->substream = subs;
228 runtime->private_data = rec;
229
230 spin_lock_init(&rec->timer_lock);
231 timer_setup(&rec->timer, emu8k_pcm_timer_func, 0);
232
233 runtime->hw = emu8k_pcm_hw;
234 runtime->hw.buffer_bytes_max = emu->mem_size - LOOP_BLANK_SIZE * 3;
235 runtime->hw.period_bytes_max = runtime->hw.buffer_bytes_max / 2;
236
237 /* use timer to update periods.. (specified in msec) */
238 snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_PERIOD_TIME,
239 (1000000 + HZ - 1) / HZ, UINT_MAX);
240
241 return 0;
242 }
243
emu8k_pcm_close(struct snd_pcm_substream * subs)244 static int emu8k_pcm_close(struct snd_pcm_substream *subs)
245 {
246 struct snd_emu8k_pcm *rec = subs->runtime->private_data;
247 kfree(rec);
248 subs->runtime->private_data = NULL;
249 return 0;
250 }
251
252 /*
253 * calculate pitch target
254 */
calc_pitch_target(int pitch)255 static int calc_pitch_target(int pitch)
256 {
257 int ptarget = 1 << (pitch >> 12);
258 if (pitch & 0x800) ptarget += (ptarget * 0x102e) / 0x2710;
259 if (pitch & 0x400) ptarget += (ptarget * 0x764) / 0x2710;
260 if (pitch & 0x200) ptarget += (ptarget * 0x389) / 0x2710;
261 ptarget += (ptarget >> 1);
262 if (ptarget > 0xffff) ptarget = 0xffff;
263 return ptarget;
264 }
265
266 /*
267 * set up the voice
268 */
setup_voice(struct snd_emu8k_pcm * rec,int ch)269 static void setup_voice(struct snd_emu8k_pcm *rec, int ch)
270 {
271 struct snd_emu8000 *hw = rec->emu;
272 unsigned int temp;
273
274 /* channel to be silent and idle */
275 EMU8000_DCYSUSV_WRITE(hw, ch, 0x0080);
276 EMU8000_VTFT_WRITE(hw, ch, 0x0000FFFF);
277 EMU8000_CVCF_WRITE(hw, ch, 0x0000FFFF);
278 EMU8000_PTRX_WRITE(hw, ch, 0);
279 EMU8000_CPF_WRITE(hw, ch, 0);
280
281 /* pitch offset */
282 EMU8000_IP_WRITE(hw, ch, rec->pitch);
283 /* set envelope parameters */
284 EMU8000_ENVVAL_WRITE(hw, ch, 0x8000);
285 EMU8000_ATKHLD_WRITE(hw, ch, 0x7f7f);
286 EMU8000_DCYSUS_WRITE(hw, ch, 0x7f7f);
287 EMU8000_ENVVOL_WRITE(hw, ch, 0x8000);
288 EMU8000_ATKHLDV_WRITE(hw, ch, 0x7f7f);
289 /* decay/sustain parameter for volume envelope is used
290 for triggerg the voice */
291 /* modulation envelope heights */
292 EMU8000_PEFE_WRITE(hw, ch, 0x0);
293 /* lfo1/2 delay */
294 EMU8000_LFO1VAL_WRITE(hw, ch, 0x8000);
295 EMU8000_LFO2VAL_WRITE(hw, ch, 0x8000);
296 /* lfo1 pitch & cutoff shift */
297 EMU8000_FMMOD_WRITE(hw, ch, 0);
298 /* lfo1 volume & freq */
299 EMU8000_TREMFRQ_WRITE(hw, ch, 0);
300 /* lfo2 pitch & freq */
301 EMU8000_FM2FRQ2_WRITE(hw, ch, 0);
302 /* pan & loop start */
303 temp = rec->panning[ch];
304 temp = (temp <<24) | ((unsigned int)rec->loop_start[ch] - 1);
305 EMU8000_PSST_WRITE(hw, ch, temp);
306 /* chorus & loop end (chorus 8bit, MSB) */
307 temp = 0; // chorus
308 temp = (temp << 24) | ((unsigned int)rec->loop_start[ch] + rec->buf_size - 1);
309 EMU8000_CSL_WRITE(hw, ch, temp);
310 /* Q & current address (Q 4bit value, MSB) */
311 temp = 0; // filterQ
312 temp = (temp << 28) | ((unsigned int)rec->loop_start[ch] - 1);
313 EMU8000_CCCA_WRITE(hw, ch, temp);
314 /* clear unknown registers */
315 EMU8000_00A0_WRITE(hw, ch, 0);
316 EMU8000_0080_WRITE(hw, ch, 0);
317 }
318
319 /*
320 * trigger the voice
321 */
start_voice(struct snd_emu8k_pcm * rec,int ch)322 static void start_voice(struct snd_emu8k_pcm *rec, int ch)
323 {
324 unsigned long flags;
325 struct snd_emu8000 *hw = rec->emu;
326 unsigned int temp, aux;
327 int pt = calc_pitch_target(rec->pitch);
328
329 /* cutoff and volume */
330 EMU8000_IFATN_WRITE(hw, ch, 0xff00);
331 EMU8000_VTFT_WRITE(hw, ch, 0xffff);
332 EMU8000_CVCF_WRITE(hw, ch, 0xffff);
333 /* trigger envelope */
334 EMU8000_DCYSUSV_WRITE(hw, ch, 0x7f7f);
335 /* set reverb and pitch target */
336 temp = 0; // reverb
337 if (rec->panning[ch] == 0)
338 aux = 0xff;
339 else
340 aux = (-rec->panning[ch]) & 0xff;
341 temp = (temp << 8) | (pt << 16) | aux;
342 EMU8000_PTRX_WRITE(hw, ch, temp);
343 EMU8000_CPF_WRITE(hw, ch, pt << 16);
344
345 /* start timer */
346 spin_lock_irqsave(&rec->timer_lock, flags);
347 if (! rec->timer_running) {
348 mod_timer(&rec->timer, jiffies + 1);
349 rec->timer_running = 1;
350 }
351 spin_unlock_irqrestore(&rec->timer_lock, flags);
352 }
353
354 /*
355 * stop the voice immediately
356 */
stop_voice(struct snd_emu8k_pcm * rec,int ch)357 static void stop_voice(struct snd_emu8k_pcm *rec, int ch)
358 {
359 unsigned long flags;
360 struct snd_emu8000 *hw = rec->emu;
361
362 EMU8000_DCYSUSV_WRITE(hw, ch, 0x807F);
363
364 /* stop timer */
365 spin_lock_irqsave(&rec->timer_lock, flags);
366 if (rec->timer_running) {
367 del_timer(&rec->timer);
368 rec->timer_running = 0;
369 }
370 spin_unlock_irqrestore(&rec->timer_lock, flags);
371 }
372
emu8k_pcm_trigger(struct snd_pcm_substream * subs,int cmd)373 static int emu8k_pcm_trigger(struct snd_pcm_substream *subs, int cmd)
374 {
375 struct snd_emu8k_pcm *rec = subs->runtime->private_data;
376 int ch;
377
378 switch (cmd) {
379 case SNDRV_PCM_TRIGGER_START:
380 for (ch = 0; ch < rec->voices; ch++)
381 start_voice(rec, ch);
382 rec->running = 1;
383 break;
384 case SNDRV_PCM_TRIGGER_STOP:
385 rec->running = 0;
386 for (ch = 0; ch < rec->voices; ch++)
387 stop_voice(rec, ch);
388 break;
389 default:
390 return -EINVAL;
391 }
392 return 0;
393 }
394
395
396 /*
397 * copy / silence ops
398 */
399
400 /*
401 * this macro should be inserted in the copy/silence loops
402 * to reduce the latency. without this, the system will hang up
403 * during the whole loop.
404 */
405 #define CHECK_SCHEDULER() \
406 do { \
407 cond_resched();\
408 if (signal_pending(current))\
409 return -EAGAIN;\
410 } while (0)
411
412 enum {
413 COPY_USER, COPY_KERNEL, FILL_SILENCE,
414 };
415
416 #define GET_VAL(sval, buf, mode) \
417 do { \
418 switch (mode) { \
419 case FILL_SILENCE: \
420 sval = 0; \
421 break; \
422 case COPY_KERNEL: \
423 sval = *buf++; \
424 break; \
425 default: \
426 if (get_user(sval, (unsigned short __user *)buf)) \
427 return -EFAULT; \
428 buf++; \
429 break; \
430 } \
431 } while (0)
432
433 #ifdef USE_NONINTERLEAVE
434
435 #define LOOP_WRITE(rec, offset, _buf, count, mode) \
436 do { \
437 struct snd_emu8000 *emu = (rec)->emu; \
438 unsigned short *buf = (unsigned short *)(_buf); \
439 snd_emu8000_write_wait(emu, 1); \
440 EMU8000_SMALW_WRITE(emu, offset); \
441 while (count > 0) { \
442 unsigned short sval; \
443 CHECK_SCHEDULER(); \
444 GET_VAL(sval, buf, mode); \
445 EMU8000_SMLD_WRITE(emu, sval); \
446 count--; \
447 } \
448 } while (0)
449
450 /* copy one channel block */
emu8k_pcm_copy(struct snd_pcm_substream * subs,int voice,unsigned long pos,void __user * src,unsigned long count)451 static int emu8k_pcm_copy(struct snd_pcm_substream *subs,
452 int voice, unsigned long pos,
453 void __user *src, unsigned long count)
454 {
455 struct snd_emu8k_pcm *rec = subs->runtime->private_data;
456
457 /* convert to word unit */
458 pos = (pos << 1) + rec->loop_start[voice];
459 count <<= 1;
460 LOOP_WRITE(rec, pos, src, count, COPY_USER);
461 return 0;
462 }
463
emu8k_pcm_copy_kernel(struct snd_pcm_substream * subs,int voice,unsigned long pos,void * src,unsigned long count)464 static int emu8k_pcm_copy_kernel(struct snd_pcm_substream *subs,
465 int voice, unsigned long pos,
466 void *src, unsigned long count)
467 {
468 struct snd_emu8k_pcm *rec = subs->runtime->private_data;
469
470 /* convert to word unit */
471 pos = (pos << 1) + rec->loop_start[voice];
472 count <<= 1;
473 LOOP_WRITE(rec, pos, src, count, COPY_KERNEL);
474 return 0;
475 }
476
477 /* make a channel block silence */
emu8k_pcm_silence(struct snd_pcm_substream * subs,int voice,unsigned long pos,unsigned long count)478 static int emu8k_pcm_silence(struct snd_pcm_substream *subs,
479 int voice, unsigned long pos, unsigned long count)
480 {
481 struct snd_emu8k_pcm *rec = subs->runtime->private_data;
482
483 /* convert to word unit */
484 pos = (pos << 1) + rec->loop_start[voice];
485 count <<= 1;
486 LOOP_WRITE(rec, pos, NULL, count, FILL_SILENCE);
487 return 0;
488 }
489
490 #else /* interleave */
491
492 #define LOOP_WRITE(rec, pos, _buf, count, mode) \
493 do { \
494 struct snd_emu8000 *emu = rec->emu; \
495 unsigned short *buf = (unsigned short *)(_buf); \
496 snd_emu8000_write_wait(emu, 1); \
497 EMU8000_SMALW_WRITE(emu, pos + rec->loop_start[0]); \
498 if (rec->voices > 1) \
499 EMU8000_SMARW_WRITE(emu, pos + rec->loop_start[1]); \
500 while (count > 0) { \
501 unsigned short sval; \
502 CHECK_SCHEDULER(); \
503 GET_VAL(sval, buf, mode); \
504 EMU8000_SMLD_WRITE(emu, sval); \
505 if (rec->voices > 1) { \
506 CHECK_SCHEDULER(); \
507 GET_VAL(sval, buf, mode); \
508 EMU8000_SMRD_WRITE(emu, sval); \
509 } \
510 count--; \
511 } \
512 } while (0)
513
514
515 /*
516 * copy the interleaved data can be done easily by using
517 * DMA "left" and "right" channels on emu8k engine.
518 */
emu8k_pcm_copy(struct snd_pcm_substream * subs,int voice,unsigned long pos,void __user * src,unsigned long count)519 static int emu8k_pcm_copy(struct snd_pcm_substream *subs,
520 int voice, unsigned long pos,
521 void __user *src, unsigned long count)
522 {
523 struct snd_emu8k_pcm *rec = subs->runtime->private_data;
524
525 /* convert to frames */
526 pos = bytes_to_frames(subs->runtime, pos);
527 count = bytes_to_frames(subs->runtime, count);
528 LOOP_WRITE(rec, pos, src, count, COPY_USER);
529 return 0;
530 }
531
emu8k_pcm_copy_kernel(struct snd_pcm_substream * subs,int voice,unsigned long pos,void * src,unsigned long count)532 static int emu8k_pcm_copy_kernel(struct snd_pcm_substream *subs,
533 int voice, unsigned long pos,
534 void *src, unsigned long count)
535 {
536 struct snd_emu8k_pcm *rec = subs->runtime->private_data;
537
538 /* convert to frames */
539 pos = bytes_to_frames(subs->runtime, pos);
540 count = bytes_to_frames(subs->runtime, count);
541 LOOP_WRITE(rec, pos, src, count, COPY_KERNEL);
542 return 0;
543 }
544
emu8k_pcm_silence(struct snd_pcm_substream * subs,int voice,unsigned long pos,unsigned long count)545 static int emu8k_pcm_silence(struct snd_pcm_substream *subs,
546 int voice, unsigned long pos, unsigned long count)
547 {
548 struct snd_emu8k_pcm *rec = subs->runtime->private_data;
549
550 /* convert to frames */
551 pos = bytes_to_frames(subs->runtime, pos);
552 count = bytes_to_frames(subs->runtime, count);
553 LOOP_WRITE(rec, pos, NULL, count, FILL_SILENCE);
554 return 0;
555 }
556 #endif
557
558
559 /*
560 * allocate a memory block
561 */
emu8k_pcm_hw_params(struct snd_pcm_substream * subs,struct snd_pcm_hw_params * hw_params)562 static int emu8k_pcm_hw_params(struct snd_pcm_substream *subs,
563 struct snd_pcm_hw_params *hw_params)
564 {
565 struct snd_emu8k_pcm *rec = subs->runtime->private_data;
566
567 if (rec->block) {
568 /* reallocation - release the old block */
569 snd_util_mem_free(rec->emu->memhdr, rec->block);
570 rec->block = NULL;
571 }
572
573 rec->allocated_bytes = params_buffer_bytes(hw_params) + LOOP_BLANK_SIZE * 4;
574 rec->block = snd_util_mem_alloc(rec->emu->memhdr, rec->allocated_bytes);
575 if (! rec->block)
576 return -ENOMEM;
577 rec->offset = EMU8000_DRAM_OFFSET + (rec->block->offset >> 1); /* in word */
578 /* at least dma_bytes must be set for non-interleaved mode */
579 subs->dma_buffer.bytes = params_buffer_bytes(hw_params);
580
581 return 0;
582 }
583
584 /*
585 * free the memory block
586 */
emu8k_pcm_hw_free(struct snd_pcm_substream * subs)587 static int emu8k_pcm_hw_free(struct snd_pcm_substream *subs)
588 {
589 struct snd_emu8k_pcm *rec = subs->runtime->private_data;
590
591 if (rec->block) {
592 int ch;
593 for (ch = 0; ch < rec->voices; ch++)
594 stop_voice(rec, ch); // to be sure
595 if (rec->dram_opened)
596 emu8k_close_dram(rec->emu);
597 snd_util_mem_free(rec->emu->memhdr, rec->block);
598 rec->block = NULL;
599 }
600 return 0;
601 }
602
603 /*
604 */
emu8k_pcm_prepare(struct snd_pcm_substream * subs)605 static int emu8k_pcm_prepare(struct snd_pcm_substream *subs)
606 {
607 struct snd_emu8k_pcm *rec = subs->runtime->private_data;
608
609 rec->pitch = 0xe000 + calc_rate_offset(subs->runtime->rate);
610 rec->last_ptr = 0;
611 rec->period_pos = 0;
612
613 rec->buf_size = subs->runtime->buffer_size;
614 rec->period_size = subs->runtime->period_size;
615 rec->voices = subs->runtime->channels;
616 rec->loop_start[0] = rec->offset + LOOP_BLANK_SIZE;
617 if (rec->voices > 1)
618 rec->loop_start[1] = rec->loop_start[0] + rec->buf_size + LOOP_BLANK_SIZE;
619 if (rec->voices > 1) {
620 rec->panning[0] = 0xff;
621 rec->panning[1] = 0x00;
622 } else
623 rec->panning[0] = 0x80;
624
625 if (! rec->dram_opened) {
626 int err, i, ch;
627
628 snd_emux_terminate_all(rec->emu->emu);
629 if ((err = emu8k_open_dram_for_pcm(rec->emu, rec->voices)) != 0)
630 return err;
631 rec->dram_opened = 1;
632
633 /* clear loop blanks */
634 snd_emu8000_write_wait(rec->emu, 0);
635 EMU8000_SMALW_WRITE(rec->emu, rec->offset);
636 for (i = 0; i < LOOP_BLANK_SIZE; i++)
637 EMU8000_SMLD_WRITE(rec->emu, 0);
638 for (ch = 0; ch < rec->voices; ch++) {
639 EMU8000_SMALW_WRITE(rec->emu, rec->loop_start[ch] + rec->buf_size);
640 for (i = 0; i < LOOP_BLANK_SIZE; i++)
641 EMU8000_SMLD_WRITE(rec->emu, 0);
642 }
643 }
644
645 setup_voice(rec, 0);
646 if (rec->voices > 1)
647 setup_voice(rec, 1);
648 return 0;
649 }
650
emu8k_pcm_pointer(struct snd_pcm_substream * subs)651 static snd_pcm_uframes_t emu8k_pcm_pointer(struct snd_pcm_substream *subs)
652 {
653 struct snd_emu8k_pcm *rec = subs->runtime->private_data;
654 if (rec->running)
655 return emu8k_get_curpos(rec, 0);
656 return 0;
657 }
658
659
660 static const struct snd_pcm_ops emu8k_pcm_ops = {
661 .open = emu8k_pcm_open,
662 .close = emu8k_pcm_close,
663 .ioctl = snd_pcm_lib_ioctl,
664 .hw_params = emu8k_pcm_hw_params,
665 .hw_free = emu8k_pcm_hw_free,
666 .prepare = emu8k_pcm_prepare,
667 .trigger = emu8k_pcm_trigger,
668 .pointer = emu8k_pcm_pointer,
669 .copy_user = emu8k_pcm_copy,
670 .copy_kernel = emu8k_pcm_copy_kernel,
671 .fill_silence = emu8k_pcm_silence,
672 };
673
674
snd_emu8000_pcm_free(struct snd_pcm * pcm)675 static void snd_emu8000_pcm_free(struct snd_pcm *pcm)
676 {
677 struct snd_emu8000 *emu = pcm->private_data;
678 emu->pcm = NULL;
679 }
680
snd_emu8000_pcm_new(struct snd_card * card,struct snd_emu8000 * emu,int index)681 int snd_emu8000_pcm_new(struct snd_card *card, struct snd_emu8000 *emu, int index)
682 {
683 struct snd_pcm *pcm;
684 int err;
685
686 if ((err = snd_pcm_new(card, "Emu8000 PCM", index, 1, 0, &pcm)) < 0)
687 return err;
688 pcm->private_data = emu;
689 pcm->private_free = snd_emu8000_pcm_free;
690 snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &emu8k_pcm_ops);
691 emu->pcm = pcm;
692
693 snd_device_register(card, pcm);
694
695 return 0;
696 }
697