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 #include "playback.h"
  22
  23
  24 /*
  25         Software stereo volume control.
  26 */
  27 static void change_volume(struct urb *urb_out, int volume[],
  28                           int bytes_per_frame)
  29 {
  30         int chn = 0;
  31
  32         if (volume[0] == 256 && volume[1] == 256)
  33                 return;  /* maximum volume - no change */
  34
  35         if (bytes_per_frame == 4) {
  36                 short *p, *buf_end;
  37                 p = (short *)urb_out->transfer_buffer;
  38                 buf_end = p + urb_out->transfer_buffer_length / sizeof(*p);
  39
  40                 for (; p < buf_end; ++p) {
  41                         *p = (*p * volume[chn & 1]) >> 8;
  42                         ++chn;
  43                 }
  44         } else if (bytes_per_frame == 6) {
  45                 unsigned char *p, *buf_end;
  46                 p = (unsigned char *)urb_out->transfer_buffer;
  47                 buf_end = p + urb_out->transfer_buffer_length;
  48
  49                 for (; p < buf_end; p += 3) {
  50                         int val;
  51                         val = p[0] + (p[1] << 8) + ((signed char)p[2] << 16);
  52                         val = (val * volume[chn & 1]) >> 8;
  53                         p[0] = val;
  54                         p[1] = val >> 8;
  55                         p[2] = val >> 16;
  56                         ++chn;
  57                 }
  58         }
  59 }
  60
  61 /*
  62         Find a free URB, prepare audio data, and submit URB.
  63 */
  64 static int submit_audio_out_urb(struct snd_pcm_substream *substream)
  65 {
  66         int index;
  67         unsigned long flags;
  68         int i, urb_size, urb_frames;
  69         struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
  70         const int bytes_per_frame = line6pcm->properties->bytes_per_frame;
  71         const int frame_increment = line6pcm->properties->snd_line6_rates.rats[0].num_min;
  72         const int frame_factor = line6pcm->properties->snd_line6_rates.rats[0].den * (USB_INTERVALS_PER_SECOND / LINE6_ISO_INTERVAL);
  73         struct snd_pcm_runtime *runtime = substream->runtime;
  74         struct urb *urb_out;
  75
  76         spin_lock_irqsave(&line6pcm->lock_audio_out, flags);
  77         index = find_first_zero_bit(&line6pcm->active_urb_out, LINE6_ISO_BUFFERS);
  78
  79         if (index < 0 || index >= LINE6_ISO_BUFFERS) {
  80                 spin_unlock_irqrestore(&line6pcm->lock_audio_out, flags);
  81                 dev_err(s2m(substream), "no free URB found\n");
  82                 return -EINVAL;
  83         }
  84
  85         urb_out = line6pcm->urb_audio_out[index];
  86         urb_size = 0;
  87
  88         for (i = 0; i < LINE6_ISO_PACKETS; ++i) {
  89                 /* compute frame size for given sampling rate */
  90                 int n, fs;
  91                 struct usb_iso_packet_descriptor *fout = &urb_out->iso_frame_desc[i];
  92                 line6pcm->count_out += frame_increment;
  93                 n = line6pcm->count_out / frame_factor;
  94                 line6pcm->count_out -= n * frame_factor;
  95                 fs = n * bytes_per_frame;
  96                 fout->offset = urb_size;
  97                 fout->length = fs;
  98                 urb_size += fs;
  99         }
 100
 101         urb_frames = urb_size / bytes_per_frame;
 102
 103         if (test_bit(BIT_PAUSE_PLAYBACK, &line6pcm->flags)) {
 104                 urb_out->transfer_buffer = line6pcm->wrap_out;
 105                 memset(line6pcm->wrap_out, 0, urb_size);
 106         } else {
 107                 if (line6pcm->pos_out + urb_frames > runtime->buffer_size) {
 108                         /*
 109                                 The transferred area goes over buffer boundary,
 110                                 copy the data to the temp buffer.
 111                         */
 112                         int len;
 113                         len = runtime->buffer_size - line6pcm->pos_out;
 114                         urb_out->transfer_buffer = line6pcm->wrap_out;
 115
 116                         if (len > 0) {
 117                                 memcpy(line6pcm->wrap_out, runtime->dma_area + line6pcm->pos_out * bytes_per_frame, len * bytes_per_frame);
 118                                 memcpy(line6pcm->wrap_out + len * bytes_per_frame, runtime->dma_area, (urb_frames - len) * bytes_per_frame);
 119                         } else
 120                                 dev_err(s2m(substream), "driver bug: len = %d\n", len);  /* this is somewhat paranoid */
 121                 } else {
 122                         /* set the buffer pointer */
 123                         urb_out->transfer_buffer = runtime->dma_area + line6pcm->pos_out * bytes_per_frame;
 124                 }
 125         }
 126
 127         if ((line6pcm->pos_out += urb_frames) >= runtime->buffer_size)
 128                 line6pcm->pos_out -= runtime->buffer_size;
 129
 130         urb_out->transfer_buffer_length = urb_size;
 131         urb_out->context = substream;
 132         change_volume(urb_out, line6pcm->volume, bytes_per_frame);
 133
 134 #if DO_DUMP_PCM_SEND
 135         for (i = 0; i < LINE6_ISO_PACKETS; ++i) {
 136                 struct usb_iso_packet_descriptor *fout = &urb_out->iso_frame_desc[i];
 137                 line6_write_hexdump(line6pcm->line6, 'P', urb_out->transfer_buffer + fout->offset, fout->length);
 138         }
 139 #endif
 140
 141         if (usb_submit_urb(urb_out, GFP_ATOMIC) == 0)
 142                 set_bit(index, &line6pcm->active_urb_out);
 143         else
 144                 dev_err(s2m(substream), "URB out #%d submission failed\n", index);
 145
 146         spin_unlock_irqrestore(&line6pcm->lock_audio_out, flags);
 147         return 0;
 148 }
 149
 150 /*
 151         Submit all currently available playback URBs.
 152 */
 153 static int submit_audio_out_all_urbs(struct snd_pcm_substream *substream)
 154 {
 155         int ret, i;
 156
 157         for (i = 0; i < LINE6_ISO_BUFFERS; ++i) {
 158                 ret = submit_audio_out_urb(substream);
 159                 if (ret < 0)
 160                         return ret;
 161         }
 162
 163         return 0;
 164 }
 165
 166 /*
 167         Unlink all currently active playback URBs.
 168 */
 169 static void unlink_audio_out_urbs(struct snd_line6_pcm *line6pcm)
 170 {
 171         unsigned int i;
 172
 173         for (i = LINE6_ISO_BUFFERS; i--;) {
 174                 if (test_bit(i, &line6pcm->active_urb_out)) {
 175                         if (!test_and_set_bit(i, &line6pcm->unlink_urb_out)) {
 176                                 struct urb *u = line6pcm->urb_audio_out[i];
 177                                 usb_unlink_urb(u);
 178                         }
 179                 }
 180         }
 181 }
 182
 183 /*
 184         Wait until unlinking of all currently active playback URBs has been finished.
 185 */
 186 static void wait_clear_audio_out_urbs(struct snd_line6_pcm *line6pcm)
 187 {
 188         int timeout = HZ;
 189         unsigned int i;
 190         int alive;
 191
 192         do {
 193                 alive = 0;
 194                 for (i = LINE6_ISO_BUFFERS; i--;) {
 195                         if (test_bit(i, &line6pcm->active_urb_out))
 196                                 alive++;
 197                 }
 198                 if (!alive)
 199                         break;
 200                 set_current_state(TASK_UNINTERRUPTIBLE);
 201                 schedule_timeout(1);
 202         } while (--timeout > 0);
 203         if (alive)
 204                 snd_printk(KERN_ERR "timeout: still %d active urbs..\n", alive);
 205
 206         line6pcm->active_urb_out = 0;
 207         line6pcm->unlink_urb_out = 0;
 208 }
 209
 210 /*
 211         Unlink all currently active playback URBs, and wait for finishing.
 212 */
 213 void unlink_wait_clear_audio_out_urbs(struct snd_line6_pcm *line6pcm)
 214 {
 215         unlink_audio_out_urbs(line6pcm);
 216         wait_clear_audio_out_urbs(line6pcm);
 217 }
 218
 219 /*
 220         Callback for completed playback URB.
 221 */
 222 static void audio_out_callback(struct urb *urb)
 223 {
 224         int i, index, length = 0, shutdown = 0;
 225         unsigned long flags;
 226
 227         struct snd_pcm_substream *substream = (struct snd_pcm_substream *)urb->context;
 228         struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
 229         struct snd_pcm_runtime *runtime = substream->runtime;
 230
 231         /* find index of URB */
 232         for (index = LINE6_ISO_BUFFERS; index--;)
 233                 if (urb == line6pcm->urb_audio_out[index])
 234                         break;
 235
 236         if (index < 0)
 237                 return;  /* URB has been unlinked asynchronously */
 238
 239         for (i = LINE6_ISO_PACKETS; i--;)
 240                 length += urb->iso_frame_desc[i].length;
 241
 242         spin_lock_irqsave(&line6pcm->lock_audio_out, flags);
 243         line6pcm->pos_out_done += length / line6pcm->properties->bytes_per_frame;
 244
 245         if (line6pcm->pos_out_done >= runtime->buffer_size)
 246                 line6pcm->pos_out_done -= runtime->buffer_size;
 247
 248         clear_bit(index, &line6pcm->active_urb_out);
 249
 250         for (i = LINE6_ISO_PACKETS; i--;)
 251                 if (urb->iso_frame_desc[i].status == -ESHUTDOWN) {
 252                         shutdown = 1;
 253                         break;
 254                 }
 255
 256         if (test_bit(index, &line6pcm->unlink_urb_out))
 257                 shutdown = 1;
 258
 259         spin_unlock_irqrestore(&line6pcm->lock_audio_out, flags);
 260
 261         if (!shutdown) {
 262                 submit_audio_out_urb(substream);
 263
 264                 if ((line6pcm->bytes_out += length) >= line6pcm->period_out) {
 265                         line6pcm->bytes_out -= line6pcm->period_out;
 266                         snd_pcm_period_elapsed(substream);
 267                 }
 268         }
 269 }
 270
 271 /* open playback callback */
 272 static int snd_line6_playback_open(struct snd_pcm_substream *substream)
 273 {
 274         int err;
 275         struct snd_pcm_runtime *runtime = substream->runtime;
 276         struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
 277
 278         err = snd_pcm_hw_constraint_ratdens(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
 279                                             (&line6pcm->properties->snd_line6_rates));
 280         if (err < 0)
 281                 return err;
 282
 283         runtime->hw = line6pcm->properties->snd_line6_playback_hw;
 284         return 0;
 285 }
 286
 287 /* close playback callback */
 288 static int snd_line6_playback_close(struct snd_pcm_substream *substream)
 289 {
 290         return 0;
 291 }
 292
 293 /* hw_params playback callback */
 294 static int snd_line6_playback_hw_params(struct snd_pcm_substream *substream, struct snd_pcm_hw_params *hw_params)
 295 {
 296         int ret;
 297         struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
 298
 299         /* -- Florian Demski [FD] */
 300         /* don't ask me why, but this fixes the bug on my machine */
 301         if (line6pcm == NULL) {
 302                 if (substream->pcm == NULL)
 303                         return -ENOMEM;
 304                 if (substream->pcm->private_data == NULL)
 305                         return -ENOMEM;
 306                 substream->private_data = substream->pcm->private_data;
 307                 line6pcm = snd_pcm_substream_chip(substream);
 308         }
 309         /* -- [FD] end */
 310
 311         ret = snd_pcm_lib_malloc_pages(substream,
 312                                        params_buffer_bytes(hw_params));
 313         if (ret < 0)
 314                 return ret;
 315
 316         line6pcm->period_out = params_period_bytes(hw_params);
 317         line6pcm->wrap_out = kmalloc(2 * LINE6_ISO_PACKET_SIZE_MAX, GFP_KERNEL);
 318
 319         if (!line6pcm->wrap_out) {
 320                 dev_err(s2m(substream), "cannot malloc wrap_out\n");
 321                 return -ENOMEM;
 322         }
 323
 324         return 0;
 325 }
 326
 327 /* hw_free playback callback */
 328 static int snd_line6_playback_hw_free(struct snd_pcm_substream *substream)
 329 {
 330         struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
 331         unlink_wait_clear_audio_out_urbs(line6pcm);
 332
 333         kfree(line6pcm->wrap_out);
 334         line6pcm->wrap_out = NULL;
 335
 336         return snd_pcm_lib_free_pages(substream);
 337 }
 338
 339 /* trigger playback callback */
 340 int snd_line6_playback_trigger(struct snd_pcm_substream *substream, int cmd)
 341 {
 342         struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
 343         int err;
 344         line6pcm->count_out = 0;
 345
 346         switch (cmd) {
 347         case SNDRV_PCM_TRIGGER_START:
 348                 if (!test_and_set_bit(BIT_RUNNING_PLAYBACK, &line6pcm->flags)) {
 349                         err = submit_audio_out_all_urbs(substream);
 350
 351                         if (err < 0) {
 352                                 clear_bit(BIT_RUNNING_PLAYBACK, &line6pcm->flags);
 353                                 return err;
 354                         }
 355                 }
 356
 357                 break;
 358
 359         case SNDRV_PCM_TRIGGER_STOP:
 360                 if (test_and_clear_bit(BIT_RUNNING_PLAYBACK, &line6pcm->flags))
 361                         unlink_audio_out_urbs(line6pcm);
 362
 363                 break;
 364
 365         case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
 366                 set_bit(BIT_PAUSE_PLAYBACK, &line6pcm->flags);
 367                 break;
 368
 369         case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
 370                 clear_bit(BIT_PAUSE_PLAYBACK, &line6pcm->flags);
 371                 break;
 372
 373         default:
 374                 return -EINVAL;
 375         }
 376
 377         return 0;
 378 }
 379
 380 /* playback pointer callback */
 381 static snd_pcm_uframes_t
 382 snd_line6_playback_pointer(struct snd_pcm_substream *substream)
 383 {
 384         struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
 385         return line6pcm->pos_out_done;
 386 }
 387
 388 /* playback operators */
 389 struct snd_pcm_ops snd_line6_playback_ops = {
 390         .open =        snd_line6_playback_open,
 391         .close =       snd_line6_playback_close,
 392         .ioctl =       snd_pcm_lib_ioctl,
 393         .hw_params =   snd_line6_playback_hw_params,
 394         .hw_free =     snd_line6_playback_hw_free,
 395         .prepare =     snd_line6_prepare,
 396         .trigger =     snd_line6_trigger,
 397         .pointer =     snd_line6_playback_pointer,
 398 };
 399
 400 int create_audio_out_urbs(struct snd_line6_pcm *line6pcm)
 401 {
 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->urb_audio_out[i] = usb_alloc_urb(LINE6_ISO_PACKETS, GFP_KERNEL);
 410
 411                 if (urb == NULL) {
 412                         dev_err(line6pcm->line6->ifcdev, "Out of memory\n");
 413                         return -ENOMEM;
 414                 }
 415
 416                 urb->dev = line6pcm->line6->usbdev;
 417                 urb->pipe = usb_sndisocpipe(line6pcm->line6->usbdev, line6pcm->ep_audio_write & USB_ENDPOINT_NUMBER_MASK);
 418                 urb->transfer_flags = URB_ISO_ASAP;
 419                 urb->start_frame = -1;
 420                 urb->number_of_packets = LINE6_ISO_PACKETS;
 421                 urb->interval = LINE6_ISO_INTERVAL;
 422                 urb->error_count = 0;
 423                 urb->complete = audio_out_callback;
 424         }
 425
 426         return 0;
 427 }