sound/isa/sb/emu8000_pcm.c

   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 <linux/slab.h>
  24 #include <sound/initval.h>
  25 #include <sound/pcm.h>
  26
  27 /*
  28  * define the following if you want to use this pcm with non-interleaved mode
  29  */
  30 /* #define USE_NONINTERLEAVE */
  31
  32 /* NOTE: for using the non-interleaved mode with alsa-lib, you have to set
  33  * mmap_emulation flag to 1 in your .asoundrc, such like
  34  *
  35  *      pcm.emu8k {
  36  *              type plug
  37  *              slave.pcm {
  38  *                      type hw
  39  *                      card 0
  40  *                      device 1
  41  *                      mmap_emulation 1
  42  *              }
  43  *      }
  44  *
  45  * besides, for the time being, the non-interleaved mode doesn't work well on
  46  * alsa-lib...
  47  */
  48
  49
  50 struct snd_emu8k_pcm {
  51         struct snd_emu8000 *emu;
  52         struct snd_pcm_substream *substream;
  53
  54         unsigned int allocated_bytes;
  55         struct snd_util_memblk *block;
  56         unsigned int offset;
  57         unsigned int buf_size;
  58         unsigned int period_size;
  59         unsigned int loop_start[2];
  60         unsigned int pitch;
  61         int panning[2];
  62         int last_ptr;
  63         int period_pos;
  64         int voices;
  65         unsigned int dram_opened: 1;
  66         unsigned int running: 1;
  67         unsigned int timer_running: 1;
  68         struct timer_list timer;
  69         spinlock_t timer_lock;
  70 };
  71
  72 #define LOOP_BLANK_SIZE         8
  73
  74
  75 /*
  76  * open up channels for the simultaneous data transfer and playback
  77  */
  78 static int
  79 emu8k_open_dram_for_pcm(struct snd_emu8000 *emu, int channels)
  80 {
  81         int i;
  82
  83         /* reserve up to 2 voices for playback */
  84         snd_emux_lock_voice(emu->emu, 0);
  85         if (channels > 1)
  86                 snd_emux_lock_voice(emu->emu, 1);
  87
  88         /* reserve 28 voices for loading */
  89         for (i = channels + 1; i < EMU8000_DRAM_VOICES; i++) {
  90                 unsigned int mode = EMU8000_RAM_WRITE;
  91                 snd_emux_lock_voice(emu->emu, i);
  92 #ifndef USE_NONINTERLEAVE
  93                 if (channels > 1 && (i & 1) != 0)
  94                         mode |= EMU8000_RAM_RIGHT;
  95 #endif
  96                 snd_emu8000_dma_chan(emu, i, mode);
  97         }
  98
  99         /* assign voice 31 and 32 to ROM */
 100         EMU8000_VTFT_WRITE(emu, 30, 0);
 101         EMU8000_PSST_WRITE(emu, 30, 0x1d8);
 102         EMU8000_CSL_WRITE(emu, 30, 0x1e0);
 103         EMU8000_CCCA_WRITE(emu, 30, 0x1d8);
 104         EMU8000_VTFT_WRITE(emu, 31, 0);
 105         EMU8000_PSST_WRITE(emu, 31, 0x1d8);
 106         EMU8000_CSL_WRITE(emu, 31, 0x1e0);
 107         EMU8000_CCCA_WRITE(emu, 31, 0x1d8);
 108
 109         return 0;
 110 }
 111
 112 /*
 113  */
 114 static void
 115 snd_emu8000_write_wait(struct snd_emu8000 *emu, int can_schedule)
 116 {
 117         while ((EMU8000_SMALW_READ(emu) & 0x80000000) != 0) {
 118                 if (can_schedule) {
 119                         schedule_timeout_interruptible(1);
 120                         if (signal_pending(current))
 121                                 break;
 122                 }
 123         }
 124 }
 125
 126 /*
 127  * close all channels
 128  */
 129 static void
 130 emu8k_close_dram(struct snd_emu8000 *emu)
 131 {
 132         int i;
 133
 134         for (i = 0; i < 2; i++)
 135                 snd_emux_unlock_voice(emu->emu, i);
 136         for (; i < EMU8000_DRAM_VOICES; i++) {
 137                 snd_emu8000_dma_chan(emu, i, EMU8000_RAM_CLOSE);
 138                 snd_emux_unlock_voice(emu->emu, i);
 139         }
 140 }
 141
 142 /*
 143  * convert Hz to AWE32 rate offset (see emux/soundfont.c)
 144  */
 145
 146 #define OFFSET_SAMPLERATE       1011119         /* base = 44100 */
 147 #define SAMPLERATE_RATIO        4096
 148
 149 static int calc_rate_offset(int hz)
 150 {
 151         return snd_sf_linear_to_log(hz, OFFSET_SAMPLERATE, SAMPLERATE_RATIO);
 152 }
 153
 154
 155 /*
 156  */
 157
 158 static struct snd_pcm_hardware emu8k_pcm_hw = {
 159 #ifdef USE_NONINTERLEAVE
 160         .info =                 SNDRV_PCM_INFO_NONINTERLEAVED,
 161 #else
 162         .info =                 SNDRV_PCM_INFO_INTERLEAVED,
 163 #endif
 164         .formats =              SNDRV_PCM_FMTBIT_S16_LE,
 165         .rates =                SNDRV_PCM_RATE_CONTINUOUS | SNDRV_PCM_RATE_8000_48000,
 166         .rate_min =             4000,
 167         .rate_max =             48000,
 168         .channels_min =         1,
 169         .channels_max =         2,
 170         .buffer_bytes_max =     (128*1024),
 171         .period_bytes_min =     1024,
 172         .period_bytes_max =     (128*1024),
 173         .periods_min =          2,
 174         .periods_max =          1024,
 175         .fifo_size =            0,
 176
 177 };
 178
 179 /*
 180  * get the current position at the given channel from CCCA register
 181  */
 182 static inline int emu8k_get_curpos(struct snd_emu8k_pcm *rec, int ch)
 183 {
 184         int val = EMU8000_CCCA_READ(rec->emu, ch) & 0xfffffff;
 185         val -= rec->loop_start[ch] - 1;
 186         return val;
 187 }
 188
 189
 190 /*
 191  * timer interrupt handler
 192  * check the current position and update the period if necessary.
 193  */
 194 static void emu8k_pcm_timer_func(unsigned long data)
 195 {
 196         struct snd_emu8k_pcm *rec = (struct snd_emu8k_pcm *)data;
 197         int ptr, delta;
 198
 199         spin_lock(&rec->timer_lock);
 200         /* update the current pointer */
 201         ptr = emu8k_get_curpos(rec, 0);
 202         if (ptr < rec->last_ptr)
 203                 delta = ptr + rec->buf_size - rec->last_ptr;
 204         else
 205                 delta = ptr - rec->last_ptr;
 206         rec->period_pos += delta;
 207         rec->last_ptr = ptr;
 208
 209         /* reprogram timer */
 210         rec->timer.expires = jiffies + 1;
 211         add_timer(&rec->timer);
 212
 213         /* update period */
 214         if (rec->period_pos >= (int)rec->period_size) {
 215                 rec->period_pos %= rec->period_size;
 216                 spin_unlock(&rec->timer_lock);
 217                 snd_pcm_period_elapsed(rec->substream);
 218                 return;
 219         }
 220         spin_unlock(&rec->timer_lock);
 221 }
 222
 223
 224 /*
 225  * open pcm
 226  * creating an instance here
 227  */
 228 static int emu8k_pcm_open(struct snd_pcm_substream *subs)
 229 {
 230         struct snd_emu8000 *emu = snd_pcm_substream_chip(subs);
 231         struct snd_emu8k_pcm *rec;
 232         struct snd_pcm_runtime *runtime = subs->runtime;
 233
 234         rec = kzalloc(sizeof(*rec), GFP_KERNEL);
 235         if (! rec)
 236                 return -ENOMEM;
 237
 238         rec->emu = emu;
 239         rec->substream = subs;
 240         runtime->private_data = rec;
 241
 242         spin_lock_init(&rec->timer_lock);
 243         init_timer(&rec->timer);
 244         rec->timer.function = emu8k_pcm_timer_func;
 245         rec->timer.data = (unsigned long)rec;
 246
 247         runtime->hw = emu8k_pcm_hw;
 248         runtime->hw.buffer_bytes_max = emu->mem_size - LOOP_BLANK_SIZE * 3;
 249         runtime->hw.period_bytes_max = runtime->hw.buffer_bytes_max / 2;
 250
 251         /* use timer to update periods.. (specified in msec) */
 252         snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_PERIOD_TIME,
 253                                      (1000000 + HZ - 1) / HZ, UINT_MAX);
 254
 255         return 0;
 256 }
 257
 258 static int emu8k_pcm_close(struct snd_pcm_substream *subs)
 259 {
 260         struct snd_emu8k_pcm *rec = subs->runtime->private_data;
 261         kfree(rec);
 262         subs->runtime->private_data = NULL;
 263         return 0;
 264 }
 265
 266 /*
 267  * calculate pitch target
 268  */
 269 static int calc_pitch_target(int pitch)
 270 {
 271         int ptarget = 1 << (pitch >> 12);
 272         if (pitch & 0x800) ptarget += (ptarget * 0x102e) / 0x2710;
 273         if (pitch & 0x400) ptarget += (ptarget * 0x764) / 0x2710;
 274         if (pitch & 0x200) ptarget += (ptarget * 0x389) / 0x2710;
 275         ptarget += (ptarget >> 1);
 276         if (ptarget > 0xffff) ptarget = 0xffff;
 277         return ptarget;
 278 }
 279
 280 /*
 281  * set up the voice
 282  */
 283 static void setup_voice(struct snd_emu8k_pcm *rec, int ch)
 284 {
 285         struct snd_emu8000 *hw = rec->emu;
 286         unsigned int temp;
 287
 288         /* channel to be silent and idle */
 289         EMU8000_DCYSUSV_WRITE(hw, ch, 0x0080);
 290         EMU8000_VTFT_WRITE(hw, ch, 0x0000FFFF);
 291         EMU8000_CVCF_WRITE(hw, ch, 0x0000FFFF);
 292         EMU8000_PTRX_WRITE(hw, ch, 0);
 293         EMU8000_CPF_WRITE(hw, ch, 0);
 294
 295         /* pitch offset */
 296         EMU8000_IP_WRITE(hw, ch, rec->pitch);
 297         /* set envelope parameters */
 298         EMU8000_ENVVAL_WRITE(hw, ch, 0x8000);
 299         EMU8000_ATKHLD_WRITE(hw, ch, 0x7f7f);
 300         EMU8000_DCYSUS_WRITE(hw, ch, 0x7f7f);
 301         EMU8000_ENVVOL_WRITE(hw, ch, 0x8000);
 302         EMU8000_ATKHLDV_WRITE(hw, ch, 0x7f7f);
 303         /* decay/sustain parameter for volume envelope is used
 304            for triggerg the voice */
 305         /* modulation envelope heights */
 306         EMU8000_PEFE_WRITE(hw, ch, 0x0);
 307         /* lfo1/2 delay */
 308         EMU8000_LFO1VAL_WRITE(hw, ch, 0x8000);
 309         EMU8000_LFO2VAL_WRITE(hw, ch, 0x8000);
 310         /* lfo1 pitch & cutoff shift */
 311         EMU8000_FMMOD_WRITE(hw, ch, 0);
 312         /* lfo1 volume & freq */
 313         EMU8000_TREMFRQ_WRITE(hw, ch, 0);
 314         /* lfo2 pitch & freq */
 315         EMU8000_FM2FRQ2_WRITE(hw, ch, 0);
 316         /* pan & loop start */
 317         temp = rec->panning[ch];
 318         temp = (temp <<24) | ((unsigned int)rec->loop_start[ch] - 1);
 319         EMU8000_PSST_WRITE(hw, ch, temp);
 320         /* chorus & loop end (chorus 8bit, MSB) */
 321         temp = 0; // chorus
 322         temp = (temp << 24) | ((unsigned int)rec->loop_start[ch] + rec->buf_size - 1);
 323         EMU8000_CSL_WRITE(hw, ch, temp);
 324         /* Q & current address (Q 4bit value, MSB) */
 325         temp = 0; // filterQ
 326         temp = (temp << 28) | ((unsigned int)rec->loop_start[ch] - 1);
 327         EMU8000_CCCA_WRITE(hw, ch, temp);
 328         /* clear unknown registers */
 329         EMU8000_00A0_WRITE(hw, ch, 0);
 330         EMU8000_0080_WRITE(hw, ch, 0);
 331 }
 332
 333 /*
 334  * trigger the voice
 335  */
 336 static void start_voice(struct snd_emu8k_pcm *rec, int ch)
 337 {
 338         unsigned long flags;
 339         struct snd_emu8000 *hw = rec->emu;
 340         unsigned int temp, aux;
 341         int pt = calc_pitch_target(rec->pitch);
 342
 343         /* cutoff and volume */
 344         EMU8000_IFATN_WRITE(hw, ch, 0xff00);
 345         EMU8000_VTFT_WRITE(hw, ch, 0xffff);
 346         EMU8000_CVCF_WRITE(hw, ch, 0xffff);
 347         /* trigger envelope */
 348         EMU8000_DCYSUSV_WRITE(hw, ch, 0x7f7f);
 349         /* set reverb and pitch target */
 350         temp = 0; // reverb
 351         if (rec->panning[ch] == 0)
 352                 aux = 0xff;
 353         else
 354                 aux = (-rec->panning[ch]) & 0xff;
 355         temp = (temp << 8) | (pt << 16) | aux;
 356         EMU8000_PTRX_WRITE(hw, ch, temp);
 357         EMU8000_CPF_WRITE(hw, ch, pt << 16);
 358
 359         /* start timer */
 360         spin_lock_irqsave(&rec->timer_lock, flags);
 361         if (! rec->timer_running) {
 362                 rec->timer.expires = jiffies + 1;
 363                 add_timer(&rec->timer);
 364                 rec->timer_running = 1;
 365         }
 366         spin_unlock_irqrestore(&rec->timer_lock, flags);
 367 }
 368
 369 /*
 370  * stop the voice immediately
 371  */
 372 static void stop_voice(struct snd_emu8k_pcm *rec, int ch)
 373 {
 374         unsigned long flags;
 375         struct snd_emu8000 *hw = rec->emu;
 376
 377         EMU8000_DCYSUSV_WRITE(hw, ch, 0x807F);
 378
 379         /* stop timer */
 380         spin_lock_irqsave(&rec->timer_lock, flags);
 381         if (rec->timer_running) {
 382                 del_timer(&rec->timer);
 383                 rec->timer_running = 0;
 384         }
 385         spin_unlock_irqrestore(&rec->timer_lock, flags);
 386 }
 387
 388 static int emu8k_pcm_trigger(struct snd_pcm_substream *subs, int cmd)
 389 {
 390         struct snd_emu8k_pcm *rec = subs->runtime->private_data;
 391         int ch;
 392
 393         switch (cmd) {
 394         case SNDRV_PCM_TRIGGER_START:
 395                 for (ch = 0; ch < rec->voices; ch++)
 396                         start_voice(rec, ch);
 397                 rec->running = 1;
 398                 break;
 399         case SNDRV_PCM_TRIGGER_STOP:
 400                 rec->running = 0;
 401                 for (ch = 0; ch < rec->voices; ch++)
 402                         stop_voice(rec, ch);
 403                 break;
 404         default:
 405                 return -EINVAL;
 406         }
 407         return 0;
 408 }
 409
 410
 411 /*
 412  * copy / silence ops
 413  */
 414
 415 /*
 416  * this macro should be inserted in the copy/silence loops
 417  * to reduce the latency.  without this, the system will hang up
 418  * during the whole loop.
 419  */
 420 #define CHECK_SCHEDULER() \
 421 do { \
 422         cond_resched();\
 423         if (signal_pending(current))\
 424                 return -EAGAIN;\
 425 } while (0)
 426
 427
 428 #ifdef USE_NONINTERLEAVE
 429 /* copy one channel block */
 430 static int emu8k_transfer_block(struct snd_emu8000 *emu, int offset, unsigned short *buf, int count)
 431 {
 432         EMU8000_SMALW_WRITE(emu, offset);
 433         while (count > 0) {
 434                 unsigned short sval;
 435                 CHECK_SCHEDULER();
 436                 get_user(sval, buf);
 437                 EMU8000_SMLD_WRITE(emu, sval);
 438                 buf++;
 439                 count--;
 440         }
 441         return 0;
 442 }
 443
 444 static int emu8k_pcm_copy(struct snd_pcm_substream *subs,
 445                           int voice,
 446                           snd_pcm_uframes_t pos,
 447                           void *src,
 448                           snd_pcm_uframes_t count)
 449 {
 450         struct snd_emu8k_pcm *rec = subs->runtime->private_data;
 451         struct snd_emu8000 *emu = rec->emu;
 452
 453         snd_emu8000_write_wait(emu, 1);
 454         if (voice == -1) {
 455                 unsigned short *buf = src;
 456                 int i, err;
 457                 count /= rec->voices;
 458                 for (i = 0; i < rec->voices; i++) {
 459                         err = emu8k_transfer_block(emu, pos + rec->loop_start[i], buf, count);
 460                         if (err < 0)
 461                                 return err;
 462                         buf += count;
 463                 }
 464                 return 0;
 465         } else {
 466                 return emu8k_transfer_block(emu, pos + rec->loop_start[voice], src, count);
 467         }
 468 }
 469
 470 /* make a channel block silence */
 471 static int emu8k_silence_block(struct snd_emu8000 *emu, int offset, int count)
 472 {
 473         EMU8000_SMALW_WRITE(emu, offset);
 474         while (count > 0) {
 475                 CHECK_SCHEDULER();
 476                 EMU8000_SMLD_WRITE(emu, 0);
 477                 count--;
 478         }
 479         return 0;
 480 }
 481
 482 static int emu8k_pcm_silence(struct snd_pcm_substream *subs,
 483                              int voice,
 484                              snd_pcm_uframes_t pos,
 485                              snd_pcm_uframes_t count)
 486 {
 487         struct snd_emu8k_pcm *rec = subs->runtime->private_data;
 488         struct snd_emu8000 *emu = rec->emu;
 489
 490         snd_emu8000_write_wait(emu, 1);
 491         if (voice == -1 && rec->voices == 1)
 492                 voice = 0;
 493         if (voice == -1) {
 494                 int err;
 495                 err = emu8k_silence_block(emu, pos + rec->loop_start[0], count / 2);
 496                 if (err < 0)
 497                         return err;
 498                 return emu8k_silence_block(emu, pos + rec->loop_start[1], count / 2);
 499         } else {
 500                 return emu8k_silence_block(emu, pos + rec->loop_start[voice], count);
 501         }
 502 }
 503
 504 #else /* interleave */
 505
 506 /*
 507  * copy the interleaved data can be done easily by using
 508  * DMA "left" and "right" channels on emu8k engine.
 509  */
 510 static int emu8k_pcm_copy(struct snd_pcm_substream *subs,
 511                           int voice,
 512                           snd_pcm_uframes_t pos,
 513                           void __user *src,
 514                           snd_pcm_uframes_t count)
 515 {
 516         struct snd_emu8k_pcm *rec = subs->runtime->private_data;
 517         struct snd_emu8000 *emu = rec->emu;
 518         unsigned short __user *buf = src;
 519
 520         snd_emu8000_write_wait(emu, 1);
 521         EMU8000_SMALW_WRITE(emu, pos + rec->loop_start[0]);
 522         if (rec->voices > 1)
 523                 EMU8000_SMARW_WRITE(emu, pos + rec->loop_start[1]);
 524
 525         while (count-- > 0) {
 526                 unsigned short sval;
 527                 CHECK_SCHEDULER();
 528                 get_user(sval, buf);
 529                 EMU8000_SMLD_WRITE(emu, sval);
 530                 buf++;
 531                 if (rec->voices > 1) {
 532                         CHECK_SCHEDULER();
 533                         get_user(sval, buf);
 534                         EMU8000_SMRD_WRITE(emu, sval);
 535                         buf++;
 536                 }
 537         }
 538         return 0;
 539 }
 540
 541 static int emu8k_pcm_silence(struct snd_pcm_substream *subs,
 542                              int voice,
 543                              snd_pcm_uframes_t pos,
 544                              snd_pcm_uframes_t count)
 545 {
 546         struct snd_emu8k_pcm *rec = subs->runtime->private_data;
 547         struct snd_emu8000 *emu = rec->emu;
 548
 549         snd_emu8000_write_wait(emu, 1);
 550         EMU8000_SMALW_WRITE(emu, rec->loop_start[0] + pos);
 551         if (rec->voices > 1)
 552                 EMU8000_SMARW_WRITE(emu, rec->loop_start[1] + pos);
 553         while (count-- > 0) {
 554                 CHECK_SCHEDULER();
 555                 EMU8000_SMLD_WRITE(emu, 0);
 556                 if (rec->voices > 1) {
 557                         CHECK_SCHEDULER();
 558                         EMU8000_SMRD_WRITE(emu, 0);
 559                 }
 560         }
 561         return 0;
 562 }
 563 #endif
 564
 565
 566 /*
 567  * allocate a memory block
 568  */
 569 static int emu8k_pcm_hw_params(struct snd_pcm_substream *subs,
 570                                struct snd_pcm_hw_params *hw_params)
 571 {
 572         struct snd_emu8k_pcm *rec = subs->runtime->private_data;
 573
 574         if (rec->block) {
 575                 /* reallocation - release the old block */
 576                 snd_util_mem_free(rec->emu->memhdr, rec->block);
 577                 rec->block = NULL;
 578         }
 579
 580         rec->allocated_bytes = params_buffer_bytes(hw_params) + LOOP_BLANK_SIZE * 4;
 581         rec->block = snd_util_mem_alloc(rec->emu->memhdr, rec->allocated_bytes);
 582         if (! rec->block)
 583                 return -ENOMEM;
 584         rec->offset = EMU8000_DRAM_OFFSET + (rec->block->offset >> 1); /* in word */
 585         /* at least dma_bytes must be set for non-interleaved mode */
 586         subs->dma_buffer.bytes = params_buffer_bytes(hw_params);
 587
 588         return 0;
 589 }
 590
 591 /*
 592  * free the memory block
 593  */
 594 static int emu8k_pcm_hw_free(struct snd_pcm_substream *subs)
 595 {
 596         struct snd_emu8k_pcm *rec = subs->runtime->private_data;
 597
 598         if (rec->block) {
 599                 int ch;
 600                 for (ch = 0; ch < rec->voices; ch++)
 601                         stop_voice(rec, ch); // to be sure
 602                 if (rec->dram_opened)
 603                         emu8k_close_dram(rec->emu);
 604                 snd_util_mem_free(rec->emu->memhdr, rec->block);
 605                 rec->block = NULL;
 606         }
 607         return 0;
 608 }
 609
 610 /*
 611  */
 612 static int emu8k_pcm_prepare(struct snd_pcm_substream *subs)
 613 {
 614         struct snd_emu8k_pcm *rec = subs->runtime->private_data;
 615
 616         rec->pitch = 0xe000 + calc_rate_offset(subs->runtime->rate);
 617         rec->last_ptr = 0;
 618         rec->period_pos = 0;
 619
 620         rec->buf_size = subs->runtime->buffer_size;
 621         rec->period_size = subs->runtime->period_size;
 622         rec->voices = subs->runtime->channels;
 623         rec->loop_start[0] = rec->offset + LOOP_BLANK_SIZE;
 624         if (rec->voices > 1)
 625                 rec->loop_start[1] = rec->loop_start[0] + rec->buf_size + LOOP_BLANK_SIZE;
 626         if (rec->voices > 1) {
 627                 rec->panning[0] = 0xff;
 628                 rec->panning[1] = 0x00;
 629         } else
 630                 rec->panning[0] = 0x80;
 631
 632         if (! rec->dram_opened) {
 633                 int err, i, ch;
 634
 635                 snd_emux_terminate_all(rec->emu->emu);
 636                 if ((err = emu8k_open_dram_for_pcm(rec->emu, rec->voices)) != 0)
 637                         return err;
 638                 rec->dram_opened = 1;
 639
 640                 /* clear loop blanks */
 641                 snd_emu8000_write_wait(rec->emu, 0);
 642                 EMU8000_SMALW_WRITE(rec->emu, rec->offset);
 643                 for (i = 0; i < LOOP_BLANK_SIZE; i++)
 644                         EMU8000_SMLD_WRITE(rec->emu, 0);
 645                 for (ch = 0; ch < rec->voices; ch++) {
 646                         EMU8000_SMALW_WRITE(rec->emu, rec->loop_start[ch] + rec->buf_size);
 647                         for (i = 0; i < LOOP_BLANK_SIZE; i++)
 648                                 EMU8000_SMLD_WRITE(rec->emu, 0);
 649                 }
 650         }
 651
 652         setup_voice(rec, 0);
 653         if (rec->voices > 1)
 654                 setup_voice(rec, 1);
 655         return 0;
 656 }
 657
 658 static snd_pcm_uframes_t emu8k_pcm_pointer(struct snd_pcm_substream *subs)
 659 {
 660         struct snd_emu8k_pcm *rec = subs->runtime->private_data;
 661         if (rec->running)
 662                 return emu8k_get_curpos(rec, 0);
 663         return 0;
 664 }
 665
 666
 667 static struct snd_pcm_ops emu8k_pcm_ops = {
 668         .open =         emu8k_pcm_open,
 669         .close =        emu8k_pcm_close,
 670         .ioctl =        snd_pcm_lib_ioctl,
 671         .hw_params =    emu8k_pcm_hw_params,
 672         .hw_free =      emu8k_pcm_hw_free,
 673         .prepare =      emu8k_pcm_prepare,
 674         .trigger =      emu8k_pcm_trigger,
 675         .pointer =      emu8k_pcm_pointer,
 676         .copy =         emu8k_pcm_copy,
 677         .silence =      emu8k_pcm_silence,
 678 };
 679
 680
 681 static void snd_emu8000_pcm_free(struct snd_pcm *pcm)
 682 {
 683         struct snd_emu8000 *emu = pcm->private_data;
 684         emu->pcm = NULL;
 685 }
 686
 687 int snd_emu8000_pcm_new(struct snd_card *card, struct snd_emu8000 *emu, int index)
 688 {
 689         struct snd_pcm *pcm;
 690         int err;
 691
 692         if ((err = snd_pcm_new(card, "Emu8000 PCM", index, 1, 0, &pcm)) < 0)
 693                 return err;
 694         pcm->private_data = emu;
 695         pcm->private_free = snd_emu8000_pcm_free;
 696         snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &emu8k_pcm_ops);
 697         emu->pcm = pcm;
 698
 699         snd_device_register(card, pcm);
 700
 701         return 0;
 702 }