kernel/sound/usb/line6/playback.c

   1 /*
   2  * Line 6 Linux USB driver
   3  *
   4  * Copyright (C) 2004-2010 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 <linux/slab.h>
  13 #include <sound/core.h>
  14 #include <sound/pcm.h>
  15 #include <sound/pcm_params.h>
  16
  17 #include "capture.h"
  18 #include "driver.h"
  19 #include "pcm.h"
  20 #include "playback.h"
  21
  22 /*
  23         Software stereo volume control.
  24 */
  25 static void change_volume(struct urb *urb_out, int volume[],
  26                           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                 __le16 *p, *buf_end;
  35
  36                 p = (__le16 *)urb_out->transfer_buffer;
  37                 buf_end = p + urb_out->transfer_buffer_length / sizeof(*p);
  38
  39                 for (; p < buf_end; ++p) {
  40                         short pv = le16_to_cpu(*p);
  41                         int val = (pv * volume[chn & 1]) >> 8;
  42                         pv = clamp(val, -0x8000, 0x7fff);
  43                         *p = cpu_to_le16(pv);
  44                         ++chn;
  45                 }
  46         } else if (bytes_per_frame == 6) {
  47                 unsigned char *p, *buf_end;
  48
  49                 p = (unsigned char *)urb_out->transfer_buffer;
  50                 buf_end = p + urb_out->transfer_buffer_length;
  51
  52                 for (; p < buf_end; p += 3) {
  53                         int val;
  54
  55                         val = p[0] + (p[1] << 8) + ((signed char)p[2] << 16);
  56                         val = (val * volume[chn & 1]) >> 8;
  57                         val = clamp(val, -0x800000, 0x7fffff);
  58                         p[0] = val;
  59                         p[1] = val >> 8;
  60                         p[2] = val >> 16;
  61                         ++chn;
  62                 }
  63         }
  64 }
  65
  66 /*
  67         Create signal for impulse response test.
  68 */
  69 static void create_impulse_test_signal(struct snd_line6_pcm *line6pcm,
  70                                        struct urb *urb_out, int bytes_per_frame)
  71 {
  72         int frames = urb_out->transfer_buffer_length / bytes_per_frame;
  73
  74         if (bytes_per_frame == 4) {
  75                 int i;
  76                 short *pi = (short *)line6pcm->prev_fbuf;
  77                 short *po = (short *)urb_out->transfer_buffer;
  78
  79                 for (i = 0; i < frames; ++i) {
  80                         po[0] = pi[0];
  81                         po[1] = 0;
  82                         pi += 2;
  83                         po += 2;
  84                 }
  85         } else if (bytes_per_frame == 6) {
  86                 int i, j;
  87                 unsigned char *pi = line6pcm->prev_fbuf;
  88                 unsigned char *po = urb_out->transfer_buffer;
  89
  90                 for (i = 0; i < frames; ++i) {
  91                         for (j = 0; j < bytes_per_frame / 2; ++j)
  92                                 po[j] = pi[j];
  93
  94                         for (; j < bytes_per_frame; ++j)
  95                                 po[j] = 0;
  96
  97                         pi += bytes_per_frame;
  98                         po += bytes_per_frame;
  99                 }
 100         }
 101         if (--line6pcm->impulse_count <= 0) {
 102                 ((unsigned char *)(urb_out->transfer_buffer))[bytes_per_frame -
 103                                                               1] =
 104                     line6pcm->impulse_volume;
 105                 line6pcm->impulse_count = line6pcm->impulse_period;
 106         }
 107 }
 108
 109 /*
 110         Add signal to buffer for software monitoring.
 111 */
 112 static void add_monitor_signal(struct urb *urb_out, unsigned char *signal,
 113                                int volume, int bytes_per_frame)
 114 {
 115         if (volume == 0)
 116                 return;         /* zero volume - no change */
 117
 118         if (bytes_per_frame == 4) {
 119                 __le16 *pi, *po, *buf_end;
 120
 121                 pi = (__le16 *)signal;
 122                 po = (__le16 *)urb_out->transfer_buffer;
 123                 buf_end = po + urb_out->transfer_buffer_length / sizeof(*po);
 124
 125                 for (; po < buf_end; ++pi, ++po) {
 126                         short pov = le16_to_cpu(*po);
 127                         short piv = le16_to_cpu(*pi);
 128                         int val = pov + ((piv * volume) >> 8);
 129                         pov = clamp(val, -0x8000, 0x7fff);
 130                         *po = cpu_to_le16(pov);
 131                 }
 132         }
 133
 134         /*
 135            We don't need to handle devices with 6 bytes per frame here
 136            since they all support hardware monitoring.
 137          */
 138 }
 139
 140 /*
 141         Find a free URB, prepare audio data, and submit URB.
 142         must be called in line6pcm->out.lock context
 143 */
 144 static int submit_audio_out_urb(struct snd_line6_pcm *line6pcm)
 145 {
 146         int index;
 147         int i, urb_size, urb_frames;
 148         int ret;
 149         const int bytes_per_frame = line6pcm->properties->bytes_per_frame;
 150         const int frame_increment =
 151                 line6pcm->properties->rates.rats[0].num_min;
 152         const int frame_factor =
 153                 line6pcm->properties->rates.rats[0].den *
 154                 (USB_INTERVALS_PER_SECOND / LINE6_ISO_INTERVAL);
 155         struct urb *urb_out;
 156
 157         index =
 158             find_first_zero_bit(&line6pcm->out.active_urbs, LINE6_ISO_BUFFERS);
 159
 160         if (index < 0 || index >= LINE6_ISO_BUFFERS) {
 161                 dev_err(line6pcm->line6->ifcdev, "no free URB found\n");
 162                 return -EINVAL;
 163         }
 164
 165         urb_out = line6pcm->out.urbs[index];
 166         urb_size = 0;
 167
 168         for (i = 0; i < LINE6_ISO_PACKETS; ++i) {
 169                 /* compute frame size for given sampling rate */
 170                 int fsize = 0;
 171                 struct usb_iso_packet_descriptor *fout =
 172                     &urb_out->iso_frame_desc[i];
 173
 174                 fsize = line6pcm->prev_fsize;
 175                 if (fsize == 0) {
 176                         int n;
 177
 178                         line6pcm->out.count += frame_increment;
 179                         n = line6pcm->out.count / frame_factor;
 180                         line6pcm->out.count -= n * frame_factor;
 181                         fsize = n * bytes_per_frame;
 182                 }
 183
 184                 fout->offset = urb_size;
 185                 fout->length = fsize;
 186                 urb_size += fsize;
 187         }
 188
 189         if (urb_size == 0) {
 190                 /* can't determine URB size */
 191                 dev_err(line6pcm->line6->ifcdev, "driver bug: urb_size = 0\n");
 192                 return -EINVAL;
 193         }
 194
 195         urb_frames = urb_size / bytes_per_frame;
 196         urb_out->transfer_buffer =
 197             line6pcm->out.buffer +
 198             index * LINE6_ISO_PACKETS * line6pcm->max_packet_size;
 199         urb_out->transfer_buffer_length = urb_size;
 200         urb_out->context = line6pcm;
 201
 202         if (test_bit(LINE6_STREAM_PCM, &line6pcm->out.running) &&
 203             !test_bit(LINE6_FLAG_PAUSE_PLAYBACK, &line6pcm->flags)) {
 204                 struct snd_pcm_runtime *runtime =
 205                     get_substream(line6pcm, SNDRV_PCM_STREAM_PLAYBACK)->runtime;
 206
 207                 if (line6pcm->out.pos + urb_frames > runtime->buffer_size) {
 208                         /*
 209                            The transferred area goes over buffer boundary,
 210                            copy the data to the temp buffer.
 211                          */
 212                         int len;
 213
 214                         len = runtime->buffer_size - line6pcm->out.pos;
 215
 216                         if (len > 0) {
 217                                 memcpy(urb_out->transfer_buffer,
 218                                        runtime->dma_area +
 219                                        line6pcm->out.pos * bytes_per_frame,
 220                                        len * bytes_per_frame);
 221                                 memcpy(urb_out->transfer_buffer +
 222                                        len * bytes_per_frame, runtime->dma_area,
 223                                        (urb_frames - len) * bytes_per_frame);
 224                         } else
 225                                 dev_err(line6pcm->line6->ifcdev, "driver bug: len = %d\n",
 226                                         len);
 227                 } else {
 228                         memcpy(urb_out->transfer_buffer,
 229                                runtime->dma_area +
 230                                line6pcm->out.pos * bytes_per_frame,
 231                                urb_out->transfer_buffer_length);
 232                 }
 233
 234                 line6pcm->out.pos += urb_frames;
 235                 if (line6pcm->out.pos >= runtime->buffer_size)
 236                         line6pcm->out.pos -= runtime->buffer_size;
 237
 238                 change_volume(urb_out, line6pcm->volume_playback,
 239                               bytes_per_frame);
 240         } else {
 241                 memset(urb_out->transfer_buffer, 0,
 242                        urb_out->transfer_buffer_length);
 243         }
 244
 245         spin_lock_nested(&line6pcm->in.lock, SINGLE_DEPTH_NESTING);
 246         if (line6pcm->prev_fbuf) {
 247                 if (test_bit(LINE6_STREAM_IMPULSE, &line6pcm->out.running)) {
 248                         create_impulse_test_signal(line6pcm, urb_out,
 249                                                    bytes_per_frame);
 250                         if (test_bit(LINE6_STREAM_PCM, &line6pcm->in.running)) {
 251                                 line6_capture_copy(line6pcm,
 252                                                    urb_out->transfer_buffer,
 253                                                    urb_out->
 254                                                    transfer_buffer_length);
 255                                 line6_capture_check_period(line6pcm,
 256                                         urb_out->transfer_buffer_length);
 257                         }
 258                 } else {
 259                         if (!(line6pcm->line6->properties->capabilities & LINE6_CAP_HWMON)
 260                             && line6pcm->out.running && line6pcm->in.running)
 261                                 add_monitor_signal(urb_out, line6pcm->prev_fbuf,
 262                                                    line6pcm->volume_monitor,
 263                                                    bytes_per_frame);
 264                 }
 265                 line6pcm->prev_fbuf = NULL;
 266                 line6pcm->prev_fsize = 0;
 267         }
 268         spin_unlock(&line6pcm->in.lock);
 269
 270         ret = usb_submit_urb(urb_out, GFP_ATOMIC);
 271
 272         if (ret == 0)
 273                 set_bit(index, &line6pcm->out.active_urbs);
 274         else
 275                 dev_err(line6pcm->line6->ifcdev,
 276                         "URB out #%d submission failed (%d)\n", index, ret);
 277
 278         return 0;
 279 }
 280
 281 /*
 282         Submit all currently available playback URBs.
 283         must be called in line6pcm->out.lock context
 284  */
 285 int line6_submit_audio_out_all_urbs(struct snd_line6_pcm *line6pcm)
 286 {
 287         int ret = 0, i;
 288
 289         for (i = 0; i < LINE6_ISO_BUFFERS; ++i) {
 290                 ret = submit_audio_out_urb(line6pcm);
 291                 if (ret < 0)
 292                         break;
 293         }
 294
 295         return ret;
 296 }
 297
 298 /*
 299         Callback for completed playback URB.
 300 */
 301 static void audio_out_callback(struct urb *urb)
 302 {
 303         int i, index, length = 0, shutdown = 0;
 304         unsigned long flags;
 305         struct snd_line6_pcm *line6pcm = (struct snd_line6_pcm *)urb->context;
 306         struct snd_pcm_substream *substream =
 307             get_substream(line6pcm, SNDRV_PCM_STREAM_PLAYBACK);
 308
 309 #if USE_CLEAR_BUFFER_WORKAROUND
 310         memset(urb->transfer_buffer, 0, urb->transfer_buffer_length);
 311 #endif
 312
 313         line6pcm->out.last_frame = urb->start_frame;
 314
 315         /* find index of URB */
 316         for (index = 0; index < LINE6_ISO_BUFFERS; index++)
 317                 if (urb == line6pcm->out.urbs[index])
 318                         break;
 319
 320         if (index >= LINE6_ISO_BUFFERS)
 321                 return;         /* URB has been unlinked asynchronously */
 322
 323         for (i = 0; i < LINE6_ISO_PACKETS; i++)
 324                 length += urb->iso_frame_desc[i].length;
 325
 326         spin_lock_irqsave(&line6pcm->out.lock, flags);
 327
 328         if (test_bit(LINE6_STREAM_PCM, &line6pcm->out.running)) {
 329                 struct snd_pcm_runtime *runtime = substream->runtime;
 330
 331                 line6pcm->out.pos_done +=
 332                     length / line6pcm->properties->bytes_per_frame;
 333
 334                 if (line6pcm->out.pos_done >= runtime->buffer_size)
 335                         line6pcm->out.pos_done -= runtime->buffer_size;
 336         }
 337
 338         clear_bit(index, &line6pcm->out.active_urbs);
 339
 340         for (i = 0; i < LINE6_ISO_PACKETS; i++)
 341                 if (urb->iso_frame_desc[i].status == -EXDEV) {
 342                         shutdown = 1;
 343                         break;
 344                 }
 345
 346         if (test_and_clear_bit(index, &line6pcm->out.unlink_urbs))
 347                 shutdown = 1;
 348
 349         if (!shutdown) {
 350                 submit_audio_out_urb(line6pcm);
 351
 352                 if (test_bit(LINE6_STREAM_PCM, &line6pcm->out.running)) {
 353                         line6pcm->out.bytes += length;
 354                         if (line6pcm->out.bytes >= line6pcm->out.period) {
 355                                 line6pcm->out.bytes %= line6pcm->out.period;
 356                                 spin_unlock(&line6pcm->out.lock);
 357                                 snd_pcm_period_elapsed(substream);
 358                                 spin_lock(&line6pcm->out.lock);
 359                         }
 360                 }
 361         }
 362         spin_unlock_irqrestore(&line6pcm->out.lock, flags);
 363 }
 364
 365 /* open playback callback */
 366 static int snd_line6_playback_open(struct snd_pcm_substream *substream)
 367 {
 368         int err;
 369         struct snd_pcm_runtime *runtime = substream->runtime;
 370         struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
 371
 372         err = snd_pcm_hw_constraint_ratdens(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
 373                                             &line6pcm->properties->rates);
 374         if (err < 0)
 375                 return err;
 376
 377         runtime->hw = line6pcm->properties->playback_hw;
 378         return 0;
 379 }
 380
 381 /* close playback callback */
 382 static int snd_line6_playback_close(struct snd_pcm_substream *substream)
 383 {
 384         return 0;
 385 }
 386
 387 /* playback operators */
 388 struct snd_pcm_ops snd_line6_playback_ops = {
 389         .open = snd_line6_playback_open,
 390         .close = snd_line6_playback_close,
 391         .ioctl = snd_pcm_lib_ioctl,
 392         .hw_params = snd_line6_hw_params,
 393         .hw_free = snd_line6_hw_free,
 394         .prepare = snd_line6_prepare,
 395         .trigger = snd_line6_trigger,
 396         .pointer = snd_line6_pointer,
 397 };
 398
 399 int line6_create_audio_out_urbs(struct snd_line6_pcm *line6pcm)
 400 {
 401         struct usb_line6 *line6 = line6pcm->line6;
 402         int i;
 403
 404         /* create audio URBs and fill in constant values: */
 405         for (i = 0; i < LINE6_ISO_BUFFERS; ++i) {
 406                 struct urb *urb;
 407
 408                 /* URB for audio out: */
 409                 urb = line6pcm->out.urbs[i] =
 410                     usb_alloc_urb(LINE6_ISO_PACKETS, GFP_KERNEL);
 411
 412                 if (urb == NULL)
 413                         return -ENOMEM;
 414
 415                 urb->dev = line6->usbdev;
 416                 urb->pipe =
 417                     usb_sndisocpipe(line6->usbdev,
 418                                     line6->properties->ep_audio_w &
 419                                     USB_ENDPOINT_NUMBER_MASK);
 420                 urb->transfer_flags = URB_ISO_ASAP;
 421                 urb->start_frame = -1;
 422                 urb->number_of_packets = LINE6_ISO_PACKETS;
 423                 urb->interval = LINE6_ISO_INTERVAL;
 424                 urb->error_count = 0;
 425                 urb->complete = audio_out_callback;
 426         }
 427
 428         return 0;
 429 }