drivers/staging/line6/playback.c

   1 /*
   2  * Line6 Linux USB driver - 0.8.0
   3  *
   4  * Copyright (C) 2004-2009 Markus Grabner (grabner@icg.tugraz.at)
   5  *
   6  *      This program is free software; you can redistribute it and/or
   7  *      modify it under the terms of the GNU General Public License as
   8  *      published by the Free Software Foundation, version 2.
   9  *
  10  */
  11
  12 #include "driver.h"
  13
  14 #include <sound/core.h>
  15 #include <sound/pcm.h>
  16 #include <sound/pcm_params.h>
  17
  18 #include "audio.h"
  19 #include "pcm.h"
  20 #include "pod.h"
  21
  22
  23 /*
  24         Software stereo volume control.
  25 */
  26 static void change_volume(struct urb *urb_out, int volume[], int bytes_per_frame)
  27 {
  28         int chn = 0;
  29
  30         if(volume[0] == 256 && volume[1] == 256)
  31                 return;  /* maximum volume - no change */
  32
  33         if(bytes_per_frame == 4) {
  34                 short *p, *buf_end;
  35                 p = (short *)urb_out->transfer_buffer;
  36                 buf_end = p + urb_out->transfer_buffer_length / sizeof(*p);
  37
  38                 for(; p < buf_end; ++p) {
  39                         *p = (*p * volume[chn & 1]) >> 8;
  40                         ++chn;
  41                 }
  42         }
  43         else if(bytes_per_frame == 6) {
  44                 unsigned char *p, *buf_end;
  45                 p = (unsigned char *)urb_out->transfer_buffer;
  46                 buf_end = p + urb_out->transfer_buffer_length;
  47
  48                 for(; p < buf_end; p += 3) {
  49                         int val = p[0] + (p[1] << 8) + ((signed char)p[2] << 16);
  50                         val = (val * volume[chn & 1]) >> 8;
  51                         p[0] = val;
  52                         p[1] = val >> 8;
  53                         p[2] = val >> 16;
  54                         ++chn;
  55                 }
  56         }
  57 }
  58
  59 /*
  60         Find a free URB, prepare audio data, and submit URB.
  61 */
  62 static int submit_audio_out_urb(struct snd_pcm_substream *substream)
  63 {
  64         int index;
  65         unsigned long flags;
  66         int i, urb_size, urb_frames;
  67         struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
  68         const int bytes_per_frame = line6pcm->properties->bytes_per_frame;
  69         const int frame_increment = line6pcm->properties->snd_line6_rates.rats[0].num_min;
  70         const int frame_factor = line6pcm->properties->snd_line6_rates.rats[0].den * (USB_INTERVALS_PER_SECOND / LINE6_ISO_INTERVAL);
  71         struct snd_pcm_runtime *runtime = substream->runtime;
  72         struct urb *urb_out;
  73
  74         spin_lock_irqsave(&line6pcm->lock_audio_out, flags);
  75         index = find_first_zero_bit(&line6pcm->active_urb_out, LINE6_ISO_BUFFERS);
  76
  77         if(index < 0 || index >= LINE6_ISO_BUFFERS) {
  78                 spin_unlock_irqrestore(&line6pcm->lock_audio_out, flags);
  79                 dev_err(s2m(substream), "no free URB found\n");
  80                 return -EINVAL;
  81         }
  82
  83         urb_out = line6pcm->urb_audio_out[index];
  84         urb_size = 0;
  85
  86         for(i = 0; i < LINE6_ISO_PACKETS; ++i) {
  87                 /* compute frame size for given sampling rate */
  88                 int n, fs;
  89                 struct usb_iso_packet_descriptor *fout = &urb_out->iso_frame_desc[i];
  90                 line6pcm->count_out += frame_increment;
  91                 n = line6pcm->count_out / frame_factor;
  92                 line6pcm->count_out -= n * frame_factor;
  93                 fs = n * bytes_per_frame;
  94                 fout->offset = urb_size;
  95                 fout->length = fs;
  96                 urb_size += fs;
  97         }
  98
  99         urb_frames = urb_size / bytes_per_frame;
 100
 101         if(test_bit(BIT_PAUSE_PLAYBACK, &line6pcm->flags)) {
 102                 urb_out->transfer_buffer = line6pcm->wrap_out;
 103                 memset(line6pcm->wrap_out, 0, urb_size);
 104         }
 105         else {
 106                 if(line6pcm->pos_out + urb_frames > runtime->buffer_size) {
 107                         /*
 108                                 The transferred area goes over buffer boundary,
 109                                 copy the data to the temp buffer.
 110                         */
 111                         int len;
 112                         len = runtime->buffer_size - line6pcm->pos_out;
 113                         urb_out->transfer_buffer = line6pcm->wrap_out;
 114
 115                         if(len > 0) {
 116                                 memcpy(line6pcm->wrap_out, runtime->dma_area + line6pcm->pos_out * bytes_per_frame, len * bytes_per_frame);
 117                                 memcpy(line6pcm->wrap_out + len * bytes_per_frame, runtime->dma_area, (urb_frames - len) * bytes_per_frame);
 118                         }
 119                         else
 120                                 dev_err(s2m(substream), "driver bug: len = %d\n", len);  /* this is somewhat paranoid */
 121                 }
 122                 else {
 123                         /* set the buffer pointer */
 124                         urb_out->transfer_buffer = runtime->dma_area + line6pcm->pos_out * bytes_per_frame;
 125                 }
 126         }
 127
 128         if((line6pcm->pos_out += urb_frames) >= runtime->buffer_size)
 129                 line6pcm->pos_out -= runtime->buffer_size;
 130
 131         urb_out->transfer_buffer_length = urb_size;
 132         urb_out->context = substream;
 133         change_volume(urb_out, line6pcm->volume, bytes_per_frame);
 134
 135 #if DO_DUMP_PCM_SEND
 136         for(i = 0; i < LINE6_ISO_PACKETS; ++i) {
 137                 struct usb_iso_packet_descriptor *fout = &urb_out->iso_frame_desc[i];
 138                 line6_write_hexdump(line6pcm->line6, 'P', urb_out->transfer_buffer + fout->offset, fout->length);
 139         }
 140 #endif
 141
 142         if(usb_submit_urb(urb_out, GFP_ATOMIC) == 0)
 143                 set_bit(index, &line6pcm->active_urb_out);
 144         else
 145                 dev_err(s2m(substream), "URB out #%d submission failed\n", index);
 146
 147         spin_unlock_irqrestore(&line6pcm->lock_audio_out, flags);
 148         return 0;
 149 }
 150
 151 /*
 152         Submit all currently available playback URBs.
 153 */
 154 static int submit_audio_out_all_urbs(struct snd_pcm_substream *substream)
 155 {
 156         int ret, i;
 157
 158         for(i = 0; i < LINE6_ISO_BUFFERS; ++i)
 159                 if((ret = submit_audio_out_urb(substream)) < 0)
 160                         return ret;
 161
 162         return 0;
 163 }
 164
 165 /*
 166         Unlink all currently active playback URBs.
 167 */
 168 static void unlink_audio_out_urbs(struct snd_line6_pcm *line6pcm)
 169 {
 170         unsigned int i;
 171
 172         for(i = LINE6_ISO_BUFFERS; i--;) {
 173                 if(test_bit(i, &line6pcm->active_urb_out)) {
 174                         if(!test_and_set_bit(i, &line6pcm->unlink_urb_out)) {
 175                                 struct urb *u = line6pcm->urb_audio_out[i];
 176                                 usb_unlink_urb(u);
 177                         }
 178                 }
 179         }
 180 }
 181
 182 /*
 183         Wait until unlinking of all currently active playback URBs has been finished.
 184 */
 185 static void wait_clear_audio_out_urbs(struct snd_line6_pcm *line6pcm)
 186 {
 187         int timeout = HZ;
 188         unsigned int i;
 189         int alive;
 190
 191         do {
 192                 alive = 0;
 193                 for (i = LINE6_ISO_BUFFERS; i--;) {
 194                         if (test_bit(i, &line6pcm->active_urb_out))
 195                                 alive++;
 196                 }
 197                 if (! alive)
 198                         break;
 199                 set_current_state(TASK_UNINTERRUPTIBLE);
 200                 schedule_timeout(1);
 201         } while (--timeout > 0);
 202         if (alive)
 203                 snd_printk(KERN_ERR "timeout: still %d active urbs..\n", alive);
 204
 205         line6pcm->active_urb_out = 0;
 206         line6pcm->unlink_urb_out = 0;
 207 }
 208
 209 /*
 210         Unlink all currently active playback URBs, and wait for finishing.
 211 */
 212 void unlink_wait_clear_audio_out_urbs(struct snd_line6_pcm *line6pcm)
 213 {
 214         unlink_audio_out_urbs(line6pcm);
 215         wait_clear_audio_out_urbs(line6pcm);
 216 }
 217
 218 /*
 219         Callback for completed playback URB.
 220 */
 221 static void audio_out_callback(struct urb *urb)
 222 {
 223         int i, index, length = 0, shutdown = 0;
 224         unsigned long flags;
 225
 226         struct snd_pcm_substream *substream = (struct snd_pcm_substream *)urb->context;
 227         struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
 228         struct snd_pcm_runtime *runtime = substream->runtime;
 229
 230         /* find index of URB */
 231         for(index = LINE6_ISO_BUFFERS; index--;)
 232                 if(urb == line6pcm->urb_audio_out[index])
 233                         break;
 234
 235         if(index < 0)
 236                 return;  /* URB has been unlinked asynchronously */
 237
 238         for(i = LINE6_ISO_PACKETS; i--;)
 239                 length += urb->iso_frame_desc[i].length;
 240
 241         spin_lock_irqsave(&line6pcm->lock_audio_out, flags);
 242         line6pcm->pos_out_done += length / line6pcm->properties->bytes_per_frame;
 243
 244         if(line6pcm->pos_out_done >= runtime->buffer_size)
 245                 line6pcm->pos_out_done -= runtime->buffer_size;
 246
 247         clear_bit(index, &line6pcm->active_urb_out);
 248
 249         for(i = LINE6_ISO_PACKETS; i--;)
 250                 if(urb->iso_frame_desc[i].status == -ESHUTDOWN) {
 251                         shutdown = 1;
 252                         break;
 253                 }
 254
 255         if(test_bit(index, &line6pcm->unlink_urb_out))
 256                 shutdown = 1;
 257
 258         spin_unlock_irqrestore(&line6pcm->lock_audio_out, flags);
 259
 260         if(!shutdown) {
 261                 submit_audio_out_urb(substream);
 262
 263                 if((line6pcm->bytes_out += length) >= line6pcm->period_out) {
 264                         line6pcm->bytes_out -= line6pcm->period_out;
 265                         snd_pcm_period_elapsed(substream);
 266                 }
 267         }
 268 }
 269
 270 /* open playback callback */
 271 static int snd_line6_playback_open(struct snd_pcm_substream *substream)
 272 {
 273         int err;
 274         struct snd_pcm_runtime *runtime = substream->runtime;
 275         struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
 276
 277         if((err = snd_pcm_hw_constraint_ratdens(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
 278                                                                                                                                                                         (&line6pcm->properties->snd_line6_rates))) < 0)
 279                 return err;
 280
 281         runtime->hw = line6pcm->properties->snd_line6_playback_hw;
 282         return 0;
 283 }
 284
 285 /* close playback callback */
 286 static int snd_line6_playback_close(struct snd_pcm_substream *substream)
 287 {
 288         return 0;
 289 }
 290
 291 /* hw_params playback callback */
 292 static int snd_line6_playback_hw_params(struct snd_pcm_substream *substream, struct snd_pcm_hw_params *hw_params)
 293 {
 294         int ret;
 295         struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
 296
 297         /* -- Florian Demski [FD] */
 298         /* don't ask me why, but this fixes the bug on my machine */
 299         if ( line6pcm == NULL ) {
 300                 if ( substream->pcm == NULL )
 301                         return -ENOMEM;
 302                 if ( substream->pcm->private_data == NULL )
 303                         return -ENOMEM;
 304                 substream->private_data = substream->pcm->private_data;
 305                 line6pcm = snd_pcm_substream_chip( substream );
 306         }
 307         /* -- [FD] end */
 308
 309         if((ret = snd_pcm_lib_malloc_pages(substream, params_buffer_bytes(hw_params))) < 0)
 310                 return ret;
 311
 312         line6pcm->period_out = params_period_bytes(hw_params);
 313         line6pcm->wrap_out = kmalloc(2 * LINE6_ISO_PACKET_SIZE_MAX, GFP_KERNEL);
 314
 315         if(!line6pcm->wrap_out) {
 316                 dev_err(s2m(substream), "cannot malloc wrap_out\n");
 317                 return -ENOMEM;
 318         }
 319
 320         return 0;
 321 }
 322
 323 /* hw_free playback callback */
 324 static int snd_line6_playback_hw_free(struct snd_pcm_substream *substream)
 325 {
 326         struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
 327         unlink_wait_clear_audio_out_urbs(line6pcm);
 328
 329         if(line6pcm->wrap_out) {
 330                 kfree(line6pcm->wrap_out);
 331                 line6pcm->wrap_out = 0;
 332         }
 333
 334         return snd_pcm_lib_free_pages(substream);
 335 }
 336
 337 /* trigger playback callback */
 338 int snd_line6_playback_trigger(struct snd_pcm_substream *substream, int cmd)
 339 {
 340         struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
 341         int err;
 342         line6pcm->count_out = 0;
 343
 344         switch(cmd) {
 345         case SNDRV_PCM_TRIGGER_START:
 346                 if(!test_and_set_bit(BIT_RUNNING_PLAYBACK, &line6pcm->flags)) {
 347                         err = submit_audio_out_all_urbs(substream);
 348
 349                         if(err < 0) {
 350                                 clear_bit(BIT_RUNNING_PLAYBACK, &line6pcm->flags);
 351                                 return err;
 352                         }
 353                 }
 354
 355                 break;
 356
 357         case SNDRV_PCM_TRIGGER_STOP:
 358                 if(test_and_clear_bit(BIT_RUNNING_PLAYBACK, &line6pcm->flags))
 359                         unlink_audio_out_urbs(line6pcm);
 360
 361                 break;
 362
 363         case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
 364                 set_bit(BIT_PAUSE_PLAYBACK, &line6pcm->flags);
 365                 break;
 366
 367         case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
 368                 clear_bit(BIT_PAUSE_PLAYBACK, &line6pcm->flags);
 369                 break;
 370
 371         default:
 372                 return -EINVAL;
 373         }
 374
 375         return 0;
 376 }
 377
 378 /* playback pointer callback */
 379 static snd_pcm_uframes_t
 380 snd_line6_playback_pointer(struct snd_pcm_substream *substream)
 381 {
 382         struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
 383         return line6pcm->pos_out_done;
 384 }
 385
 386 /* playback operators */
 387 struct snd_pcm_ops snd_line6_playback_ops = {
 388         .open =        snd_line6_playback_open,
 389         .close =       snd_line6_playback_close,
 390         .ioctl =       snd_pcm_lib_ioctl,
 391         .hw_params =   snd_line6_playback_hw_params,
 392         .hw_free =     snd_line6_playback_hw_free,
 393         .prepare =     snd_line6_prepare,
 394         .trigger =     snd_line6_trigger,
 395         .pointer =     snd_line6_playback_pointer,
 396 };
 397
 398 int create_audio_out_urbs(struct snd_line6_pcm *line6pcm)
 399 {
 400         int i;
 401
 402         /* create audio URBs and fill in constant values: */
 403         for(i = 0; i < LINE6_ISO_BUFFERS; ++i) {
 404                 struct urb *urb;
 405
 406                 /* URB for audio out: */
 407                 urb = line6pcm->urb_audio_out[i] = usb_alloc_urb(LINE6_ISO_PACKETS, GFP_KERNEL);
 408
 409                 if(urb == NULL) {
 410                         dev_err(line6pcm->line6->ifcdev, "Out of memory\n");
 411                         return -ENOMEM;
 412                 }
 413
 414                 urb->dev = line6pcm->line6->usbdev;
 415                 urb->pipe = usb_sndisocpipe(line6pcm->line6->usbdev, line6pcm->ep_audio_write & USB_ENDPOINT_NUMBER_MASK);
 416                 urb->transfer_flags = URB_ISO_ASAP;
 417                 urb->start_frame = -1;
 418                 urb->number_of_packets = LINE6_ISO_PACKETS;
 419                 urb->interval = LINE6_ISO_INTERVAL;
 420                 urb->error_count = 0;
 421                 urb->complete = audio_out_callback;
 422         }
 423
 424         return 0;
 425 }