sound/firewire/amdtp.c

   1 /*
   2  * Audio and Music Data Transmission Protocol (IEC 61883-6) streams
   3  * with Common Isochronous Packet (IEC 61883-1) headers
   4  *
   5  * Copyright (c) Clemens Ladisch <clemens@ladisch.de>
   6  * Licensed under the terms of the GNU General Public License, version 2.
   7  */
   8
   9 #include <linux/device.h>
  10 #include <linux/err.h>
  11 #include <linux/firewire.h>
  12 #include <linux/module.h>
  13 #include <linux/slab.h>
  14 #include <linux/sched.h>
  15 #include <sound/pcm.h>
  16 #include <sound/rawmidi.h>
  17 #include "amdtp.h"
  18
  19 #define TICKS_PER_CYCLE         3072
  20 #define CYCLES_PER_SECOND       8000
  21 #define TICKS_PER_SECOND        (TICKS_PER_CYCLE * CYCLES_PER_SECOND)
  22
  23 #define TRANSFER_DELAY_TICKS    0x2e00 /* 479.17 µs */
  24
  25 /* isochronous header parameters */
  26 #define ISO_DATA_LENGTH_SHIFT   16
  27 #define TAG_CIP                 1
  28
  29 /* common isochronous packet header parameters */
  30 #define CIP_EOH                 (1u << 31)
  31 #define CIP_EOH_MASK            0x80000000
  32 #define CIP_FMT_AM              (0x10 << 24)
  33 #define CIP_FMT_MASK            0x3f000000
  34 #define CIP_SYT_MASK            0x0000ffff
  35 #define CIP_SYT_NO_INFO         0xffff
  36 #define CIP_FDF_MASK            0x00ff0000
  37 #define CIP_FDF_SFC_SHIFT       16
  38
  39 /*
  40  * Audio and Music transfer protocol specific parameters
  41  * only "Clock-based rate control mode" is supported
  42  */
  43 #define AMDTP_FDF_AM824         (0 << (CIP_FDF_SFC_SHIFT + 3))
  44 #define AMDTP_FDF_NO_DATA       0xff
  45 #define AMDTP_DBS_MASK          0x00ff0000
  46 #define AMDTP_DBS_SHIFT         16
  47 #define AMDTP_DBC_MASK          0x000000ff
  48
  49 /* TODO: make these configurable */
  50 #define INTERRUPT_INTERVAL      16
  51 #define QUEUE_LENGTH            48
  52
  53 #define IN_PACKET_HEADER_SIZE   4
  54 #define OUT_PACKET_HEADER_SIZE  0
  55
  56 static void pcm_period_tasklet(unsigned long data);
  57
  58 /**
  59  * amdtp_stream_init - initialize an AMDTP stream structure
  60  * @s: the AMDTP stream to initialize
  61  * @unit: the target of the stream
  62  * @dir: the direction of stream
  63  * @flags: the packet transmission method to use
  64  */
  65 int amdtp_stream_init(struct amdtp_stream *s, struct fw_unit *unit,
  66                       enum amdtp_stream_direction dir, enum cip_flags flags)
  67 {
  68         s->unit = fw_unit_get(unit);
  69         s->direction = dir;
  70         s->flags = flags;
  71         s->context = ERR_PTR(-1);
  72         mutex_init(&s->mutex);
  73         tasklet_init(&s->period_tasklet, pcm_period_tasklet, (unsigned long)s);
  74         s->packet_index = 0;
  75
  76         init_waitqueue_head(&s->callback_wait);
  77         s->callbacked = false;
  78         s->sync_slave = NULL;
  79
  80         return 0;
  81 }
  82 EXPORT_SYMBOL(amdtp_stream_init);
  83
  84 /**
  85  * amdtp_stream_destroy - free stream resources
  86  * @s: the AMDTP stream to destroy
  87  */
  88 void amdtp_stream_destroy(struct amdtp_stream *s)
  89 {
  90         WARN_ON(amdtp_stream_running(s));
  91         mutex_destroy(&s->mutex);
  92         fw_unit_put(s->unit);
  93 }
  94 EXPORT_SYMBOL(amdtp_stream_destroy);
  95
  96 const unsigned int amdtp_syt_intervals[CIP_SFC_COUNT] = {
  97         [CIP_SFC_32000]  =  8,
  98         [CIP_SFC_44100]  =  8,
  99         [CIP_SFC_48000]  =  8,
 100         [CIP_SFC_88200]  = 16,
 101         [CIP_SFC_96000]  = 16,
 102         [CIP_SFC_176400] = 32,
 103         [CIP_SFC_192000] = 32,
 104 };
 105 EXPORT_SYMBOL(amdtp_syt_intervals);
 106
 107 /**
 108  * amdtp_stream_set_parameters - set stream parameters
 109  * @s: the AMDTP stream to configure
 110  * @rate: the sample rate
 111  * @pcm_channels: the number of PCM samples in each data block, to be encoded
 112  *                as AM824 multi-bit linear audio
 113  * @midi_ports: the number of MIDI ports (i.e., MPX-MIDI Data Channels)
 114  *
 115  * The parameters must be set before the stream is started, and must not be
 116  * changed while the stream is running.
 117  */
 118 void amdtp_stream_set_parameters(struct amdtp_stream *s,
 119                                  unsigned int rate,
 120                                  unsigned int pcm_channels,
 121                                  unsigned int midi_ports)
 122 {
 123         static const unsigned int rates[] = {
 124                 [CIP_SFC_32000]  =  32000,
 125                 [CIP_SFC_44100]  =  44100,
 126                 [CIP_SFC_48000]  =  48000,
 127                 [CIP_SFC_88200]  =  88200,
 128                 [CIP_SFC_96000]  =  96000,
 129                 [CIP_SFC_176400] = 176400,
 130                 [CIP_SFC_192000] = 192000,
 131         };
 132         unsigned int sfc, midi_channels;
 133
 134         midi_channels = DIV_ROUND_UP(midi_ports, 8);
 135
 136         if (WARN_ON(amdtp_stream_running(s)) ||
 137             WARN_ON(midi_channels > AMDTP_MAX_CHANNELS_FOR_MIDI))
 138                 return;
 139
 140         for (sfc = 0; sfc < CIP_SFC_COUNT; ++sfc)
 141                 if (rates[sfc] == rate)
 142                         goto sfc_found;
 143         WARN_ON(1);
 144         return;
 145
 146 sfc_found:
 147         s->dual_wire = (s->flags & CIP_HI_DUALWIRE) && sfc > CIP_SFC_96000;
 148         if (s->dual_wire) {
 149                 sfc -= 2;
 150                 rate /= 2;
 151                 pcm_channels *= 2;
 152         }
 153         s->sfc = sfc;
 154         s->data_block_quadlets = pcm_channels + midi_channels;
 155         s->pcm_channels = pcm_channels;
 156         s->midi_ports = midi_ports;
 157
 158         s->syt_interval = amdtp_syt_intervals[sfc];
 159
 160         /* default buffering in the device */
 161         s->transfer_delay = TRANSFER_DELAY_TICKS - TICKS_PER_CYCLE;
 162         if (s->flags & CIP_BLOCKING)
 163                 /* additional buffering needed to adjust for no-data packets */
 164                 s->transfer_delay += TICKS_PER_SECOND * s->syt_interval / rate;
 165 }
 166 EXPORT_SYMBOL(amdtp_stream_set_parameters);
 167
 168 /**
 169  * amdtp_stream_get_max_payload - get the stream's packet size
 170  * @s: the AMDTP stream
 171  *
 172  * This function must not be called before the stream has been configured
 173  * with amdtp_stream_set_parameters().
 174  */
 175 unsigned int amdtp_stream_get_max_payload(struct amdtp_stream *s)
 176 {
 177         return 8 + s->syt_interval * s->data_block_quadlets * 4;
 178 }
 179 EXPORT_SYMBOL(amdtp_stream_get_max_payload);
 180
 181 static void amdtp_write_s16(struct amdtp_stream *s,
 182                             struct snd_pcm_substream *pcm,
 183                             __be32 *buffer, unsigned int frames);
 184 static void amdtp_write_s32(struct amdtp_stream *s,
 185                             struct snd_pcm_substream *pcm,
 186                             __be32 *buffer, unsigned int frames);
 187 static void amdtp_write_s16_dualwire(struct amdtp_stream *s,
 188                                      struct snd_pcm_substream *pcm,
 189                                      __be32 *buffer, unsigned int frames);
 190 static void amdtp_write_s32_dualwire(struct amdtp_stream *s,
 191                                      struct snd_pcm_substream *pcm,
 192                                      __be32 *buffer, unsigned int frames);
 193 static void amdtp_read_s32(struct amdtp_stream *s,
 194                            struct snd_pcm_substream *pcm,
 195                            __be32 *buffer, unsigned int frames);
 196 static void amdtp_read_s32_dualwire(struct amdtp_stream *s,
 197                                     struct snd_pcm_substream *pcm,
 198                                     __be32 *buffer, unsigned int frames);
 199
 200 /**
 201  * amdtp_stream_set_pcm_format - set the PCM format
 202  * @s: the AMDTP stream to configure
 203  * @format: the format of the ALSA PCM device
 204  *
 205  * The sample format must be set after the other paramters (rate/PCM channels/
 206  * MIDI) and before the stream is started, and must not be changed while the
 207  * stream is running.
 208  */
 209 void amdtp_stream_set_pcm_format(struct amdtp_stream *s,
 210                                  snd_pcm_format_t format)
 211 {
 212         if (WARN_ON(amdtp_stream_pcm_running(s)))
 213                 return;
 214
 215         switch (format) {
 216         default:
 217                 WARN_ON(1);
 218                 /* fall through */
 219         case SNDRV_PCM_FORMAT_S16:
 220                 if (s->direction == AMDTP_OUT_STREAM) {
 221                         if (s->dual_wire)
 222                                 s->transfer_samples = amdtp_write_s16_dualwire;
 223                         else
 224                                 s->transfer_samples = amdtp_write_s16;
 225                         break;
 226                 }
 227                 WARN_ON(1);
 228                 /* fall through */
 229         case SNDRV_PCM_FORMAT_S32:
 230                 if (s->direction == AMDTP_OUT_STREAM) {
 231                         if (s->dual_wire)
 232                                 s->transfer_samples = amdtp_write_s32_dualwire;
 233                         else
 234                                 s->transfer_samples = amdtp_write_s32;
 235                 } else {
 236                         if (s->dual_wire)
 237                                 s->transfer_samples = amdtp_read_s32_dualwire;
 238                         else
 239                                 s->transfer_samples = amdtp_read_s32;
 240                 }
 241                 break;
 242         }
 243 }
 244 EXPORT_SYMBOL(amdtp_stream_set_pcm_format);
 245
 246 /**
 247  * amdtp_stream_pcm_prepare - prepare PCM device for running
 248  * @s: the AMDTP stream
 249  *
 250  * This function should be called from the PCM device's .prepare callback.
 251  */
 252 void amdtp_stream_pcm_prepare(struct amdtp_stream *s)
 253 {
 254         tasklet_kill(&s->period_tasklet);
 255         s->pcm_buffer_pointer = 0;
 256         s->pcm_period_pointer = 0;
 257         s->pointer_flush = true;
 258 }
 259 EXPORT_SYMBOL(amdtp_stream_pcm_prepare);
 260
 261 static unsigned int calculate_data_blocks(struct amdtp_stream *s)
 262 {
 263         unsigned int phase, data_blocks;
 264
 265         if (s->flags & CIP_BLOCKING)
 266                 data_blocks = s->syt_interval;
 267         else if (!cip_sfc_is_base_44100(s->sfc)) {
 268                 /* Sample_rate / 8000 is an integer, and precomputed. */
 269                 data_blocks = s->data_block_state;
 270         } else {
 271                 phase = s->data_block_state;
 272
 273                 /*
 274                  * This calculates the number of data blocks per packet so that
 275                  * 1) the overall rate is correct and exactly synchronized to
 276                  *    the bus clock, and
 277                  * 2) packets with a rounded-up number of blocks occur as early
 278                  *    as possible in the sequence (to prevent underruns of the
 279                  *    device's buffer).
 280                  */
 281                 if (s->sfc == CIP_SFC_44100)
 282                         /* 6 6 5 6 5 6 5 ... */
 283                         data_blocks = 5 + ((phase & 1) ^
 284                                            (phase == 0 || phase >= 40));
 285                 else
 286                         /* 12 11 11 11 11 ... or 23 22 22 22 22 ... */
 287                         data_blocks = 11 * (s->sfc >> 1) + (phase == 0);
 288                 if (++phase >= (80 >> (s->sfc >> 1)))
 289                         phase = 0;
 290                 s->data_block_state = phase;
 291         }
 292
 293         return data_blocks;
 294 }
 295
 296 static unsigned int calculate_syt(struct amdtp_stream *s,
 297                                   unsigned int cycle)
 298 {
 299         unsigned int syt_offset, phase, index, syt;
 300
 301         if (s->last_syt_offset < TICKS_PER_CYCLE) {
 302                 if (!cip_sfc_is_base_44100(s->sfc))
 303                         syt_offset = s->last_syt_offset + s->syt_offset_state;
 304                 else {
 305                 /*
 306                  * The time, in ticks, of the n'th SYT_INTERVAL sample is:
 307                  *   n * SYT_INTERVAL * 24576000 / sample_rate
 308                  * Modulo TICKS_PER_CYCLE, the difference between successive
 309                  * elements is about 1386.23.  Rounding the results of this
 310                  * formula to the SYT precision results in a sequence of
 311                  * differences that begins with:
 312                  *   1386 1386 1387 1386 1386 1386 1387 1386 1386 1386 1387 ...
 313                  * This code generates _exactly_ the same sequence.
 314                  */
 315                         phase = s->syt_offset_state;
 316                         index = phase % 13;
 317                         syt_offset = s->last_syt_offset;
 318                         syt_offset += 1386 + ((index && !(index & 3)) ||
 319                                               phase == 146);
 320                         if (++phase >= 147)
 321                                 phase = 0;
 322                         s->syt_offset_state = phase;
 323                 }
 324         } else
 325                 syt_offset = s->last_syt_offset - TICKS_PER_CYCLE;
 326         s->last_syt_offset = syt_offset;
 327
 328         if (syt_offset < TICKS_PER_CYCLE) {
 329                 syt_offset += s->transfer_delay;
 330                 syt = (cycle + syt_offset / TICKS_PER_CYCLE) << 12;
 331                 syt += syt_offset % TICKS_PER_CYCLE;
 332
 333                 return syt & CIP_SYT_MASK;
 334         } else {
 335                 return CIP_SYT_NO_INFO;
 336         }
 337 }
 338
 339 static void amdtp_write_s32(struct amdtp_stream *s,
 340                             struct snd_pcm_substream *pcm,
 341                             __be32 *buffer, unsigned int frames)
 342 {
 343         struct snd_pcm_runtime *runtime = pcm->runtime;
 344         unsigned int channels, remaining_frames, frame_step, i, c;
 345         const u32 *src;
 346
 347         channels = s->pcm_channels;
 348         src = (void *)runtime->dma_area +
 349                         frames_to_bytes(runtime, s->pcm_buffer_pointer);
 350         remaining_frames = runtime->buffer_size - s->pcm_buffer_pointer;
 351         frame_step = s->data_block_quadlets - channels;
 352
 353         for (i = 0; i < frames; ++i) {
 354                 for (c = 0; c < channels; ++c) {
 355                         *buffer = cpu_to_be32((*src >> 8) | 0x40000000);
 356                         src++;
 357                         buffer++;
 358                 }
 359                 buffer += frame_step;
 360                 if (--remaining_frames == 0)
 361                         src = (void *)runtime->dma_area;
 362         }
 363 }
 364
 365 static void amdtp_write_s16(struct amdtp_stream *s,
 366                             struct snd_pcm_substream *pcm,
 367                             __be32 *buffer, unsigned int frames)
 368 {
 369         struct snd_pcm_runtime *runtime = pcm->runtime;
 370         unsigned int channels, remaining_frames, frame_step, i, c;
 371         const u16 *src;
 372
 373         channels = s->pcm_channels;
 374         src = (void *)runtime->dma_area +
 375                         frames_to_bytes(runtime, s->pcm_buffer_pointer);
 376         remaining_frames = runtime->buffer_size - s->pcm_buffer_pointer;
 377         frame_step = s->data_block_quadlets - channels;
 378
 379         for (i = 0; i < frames; ++i) {
 380                 for (c = 0; c < channels; ++c) {
 381                         *buffer = cpu_to_be32((*src << 8) | 0x40000000);
 382                         src++;
 383                         buffer++;
 384                 }
 385                 buffer += frame_step;
 386                 if (--remaining_frames == 0)
 387                         src = (void *)runtime->dma_area;
 388         }
 389 }
 390
 391 static void amdtp_write_s32_dualwire(struct amdtp_stream *s,
 392                                      struct snd_pcm_substream *pcm,
 393                                      __be32 *buffer, unsigned int frames)
 394 {
 395         struct snd_pcm_runtime *runtime = pcm->runtime;
 396         unsigned int channels, frame_adjust_1, frame_adjust_2, i, c;
 397         const u32 *src;
 398
 399         channels = s->pcm_channels;
 400         src = (void *)runtime->dma_area +
 401                         s->pcm_buffer_pointer * (runtime->frame_bits / 8);
 402         frame_adjust_1 = channels - 1;
 403         frame_adjust_2 = 1 - (s->data_block_quadlets - channels);
 404
 405         channels /= 2;
 406         for (i = 0; i < frames; ++i) {
 407                 for (c = 0; c < channels; ++c) {
 408                         *buffer = cpu_to_be32((*src >> 8) | 0x40000000);
 409                         src++;
 410                         buffer += 2;
 411                 }
 412                 buffer -= frame_adjust_1;
 413                 for (c = 0; c < channels; ++c) {
 414                         *buffer = cpu_to_be32((*src >> 8) | 0x40000000);
 415                         src++;
 416                         buffer += 2;
 417                 }
 418                 buffer -= frame_adjust_2;
 419         }
 420 }
 421
 422 static void amdtp_write_s16_dualwire(struct amdtp_stream *s,
 423                                      struct snd_pcm_substream *pcm,
 424                                      __be32 *buffer, unsigned int frames)
 425 {
 426         struct snd_pcm_runtime *runtime = pcm->runtime;
 427         unsigned int channels, frame_adjust_1, frame_adjust_2, i, c;
 428         const u16 *src;
 429
 430         channels = s->pcm_channels;
 431         src = (void *)runtime->dma_area +
 432                         s->pcm_buffer_pointer * (runtime->frame_bits / 8);
 433         frame_adjust_1 = channels - 1;
 434         frame_adjust_2 = 1 - (s->data_block_quadlets - channels);
 435
 436         channels /= 2;
 437         for (i = 0; i < frames; ++i) {
 438                 for (c = 0; c < channels; ++c) {
 439                         *buffer = cpu_to_be32((*src << 8) | 0x40000000);
 440                         src++;
 441                         buffer += 2;
 442                 }
 443                 buffer -= frame_adjust_1;
 444                 for (c = 0; c < channels; ++c) {
 445                         *buffer = cpu_to_be32((*src << 8) | 0x40000000);
 446                         src++;
 447                         buffer += 2;
 448                 }
 449                 buffer -= frame_adjust_2;
 450         }
 451 }
 452
 453 static void amdtp_read_s32(struct amdtp_stream *s,
 454                            struct snd_pcm_substream *pcm,
 455                            __be32 *buffer, unsigned int frames)
 456 {
 457         struct snd_pcm_runtime *runtime = pcm->runtime;
 458         unsigned int channels, remaining_frames, i, c;
 459         u32 *dst;
 460
 461         channels = s->pcm_channels;
 462         dst  = (void *)runtime->dma_area +
 463                         frames_to_bytes(runtime, s->pcm_buffer_pointer);
 464         remaining_frames = runtime->buffer_size - s->pcm_buffer_pointer;
 465
 466         for (i = 0; i < frames; ++i) {
 467                 for (c = 0; c < channels; ++c) {
 468                         *dst = be32_to_cpu(buffer[c]) << 8;
 469                         dst++;
 470                 }
 471                 buffer += s->data_block_quadlets;
 472                 if (--remaining_frames == 0)
 473                         dst = (void *)runtime->dma_area;
 474         }
 475 }
 476
 477 static void amdtp_read_s32_dualwire(struct amdtp_stream *s,
 478                                     struct snd_pcm_substream *pcm,
 479                                     __be32 *buffer, unsigned int frames)
 480 {
 481         struct snd_pcm_runtime *runtime = pcm->runtime;
 482         unsigned int channels, remaining_frames, i, c;
 483         u32 *dst;
 484
 485         dst = (void *)runtime->dma_area +
 486                         frames_to_bytes(runtime, s->pcm_buffer_pointer);
 487         remaining_frames = runtime->buffer_size - s->pcm_buffer_pointer;
 488         channels = s->pcm_channels / 2;
 489
 490         for (i = 0; i < frames; ++i) {
 491                 for (c = 0; c < channels; ++c) {
 492                         *dst = be32_to_cpu(buffer[c * 2]) << 8;
 493                         dst++;
 494                 }
 495                 buffer += 1;
 496                 for (c = 0; c < channels; ++c) {
 497                         *dst = be32_to_cpu(buffer[c * 2]) << 8;
 498                         dst++;
 499                 }
 500                 buffer += s->data_block_quadlets - 1;
 501                 if (--remaining_frames == 0)
 502                         dst = (void *)runtime->dma_area;
 503         }
 504 }
 505
 506 static void amdtp_fill_pcm_silence(struct amdtp_stream *s,
 507                                    __be32 *buffer, unsigned int frames)
 508 {
 509         unsigned int i, c;
 510
 511         for (i = 0; i < frames; ++i) {
 512                 for (c = 0; c < s->pcm_channels; ++c)
 513                         buffer[c] = cpu_to_be32(0x40000000);
 514                 buffer += s->data_block_quadlets;
 515         }
 516 }
 517
 518 static void amdtp_fill_midi(struct amdtp_stream *s,
 519                             __be32 *buffer, unsigned int frames)
 520 {
 521         unsigned int f, port;
 522         u8 *b;
 523
 524         for (f = 0; f < frames; f++) {
 525                 buffer[s->pcm_channels + 1] = 0;
 526                 b = (u8 *)&buffer[s->pcm_channels + 1];
 527
 528                 port = (s->data_block_counter + f) % 8;
 529                 if ((s->midi[port] == NULL) ||
 530                     (snd_rawmidi_transmit(s->midi[port], b + 1, 1) <= 0))
 531                         b[0] = 0x80;
 532                 else
 533                         b[0] = 0x81;
 534
 535                 buffer += s->data_block_quadlets;
 536         }
 537 }
 538
 539 static void amdtp_pull_midi(struct amdtp_stream *s,
 540                             __be32 *buffer, unsigned int frames)
 541 {
 542         unsigned int f, port;
 543         int len;
 544         u8 *b;
 545
 546         for (f = 0; f < frames; f++) {
 547                 port = (s->data_block_counter + f) % 8;
 548                 b = (u8 *)&buffer[s->pcm_channels + 1];
 549
 550                 len = b[0] - 0x80;
 551                 if ((1 <= len) &&  (len <= 3) && (s->midi[port]))
 552                         snd_rawmidi_receive(s->midi[port], b + 1, len);
 553
 554                 buffer += s->data_block_quadlets;
 555         }
 556 }
 557
 558 static void update_pcm_pointers(struct amdtp_stream *s,
 559                                 struct snd_pcm_substream *pcm,
 560                                 unsigned int frames)
 561 {       unsigned int ptr;
 562
 563         if (s->dual_wire)
 564                 frames *= 2;
 565
 566         ptr = s->pcm_buffer_pointer + frames;
 567         if (ptr >= pcm->runtime->buffer_size)
 568                 ptr -= pcm->runtime->buffer_size;
 569         ACCESS_ONCE(s->pcm_buffer_pointer) = ptr;
 570
 571         s->pcm_period_pointer += frames;
 572         if (s->pcm_period_pointer >= pcm->runtime->period_size) {
 573                 s->pcm_period_pointer -= pcm->runtime->period_size;
 574                 s->pointer_flush = false;
 575                 tasklet_hi_schedule(&s->period_tasklet);
 576         }
 577 }
 578
 579 static void pcm_period_tasklet(unsigned long data)
 580 {
 581         struct amdtp_stream *s = (void *)data;
 582         struct snd_pcm_substream *pcm = ACCESS_ONCE(s->pcm);
 583
 584         if (pcm)
 585                 snd_pcm_period_elapsed(pcm);
 586 }
 587
 588 static int queue_packet(struct amdtp_stream *s,
 589                         unsigned int header_length,
 590                         unsigned int payload_length, bool skip)
 591 {
 592         struct fw_iso_packet p = {0};
 593         int err = 0;
 594
 595         if (IS_ERR(s->context))
 596                 goto end;
 597
 598         p.interrupt = IS_ALIGNED(s->packet_index + 1, INTERRUPT_INTERVAL);
 599         p.tag = TAG_CIP;
 600         p.header_length = header_length;
 601         p.payload_length = (!skip) ? payload_length : 0;
 602         p.skip = skip;
 603         err = fw_iso_context_queue(s->context, &p, &s->buffer.iso_buffer,
 604                                    s->buffer.packets[s->packet_index].offset);
 605         if (err < 0) {
 606                 dev_err(&s->unit->device, "queueing error: %d\n", err);
 607                 goto end;
 608         }
 609
 610         if (++s->packet_index >= QUEUE_LENGTH)
 611                 s->packet_index = 0;
 612 end:
 613         return err;
 614 }
 615
 616 static inline int queue_out_packet(struct amdtp_stream *s,
 617                                    unsigned int payload_length, bool skip)
 618 {
 619         return queue_packet(s, OUT_PACKET_HEADER_SIZE,
 620                             payload_length, skip);
 621 }
 622
 623 static inline int queue_in_packet(struct amdtp_stream *s)
 624 {
 625         return queue_packet(s, IN_PACKET_HEADER_SIZE,
 626                             amdtp_stream_get_max_payload(s), false);
 627 }
 628
 629 static void handle_out_packet(struct amdtp_stream *s, unsigned int syt)
 630 {
 631         __be32 *buffer;
 632         unsigned int data_blocks, payload_length;
 633         struct snd_pcm_substream *pcm;
 634
 635         if (s->packet_index < 0)
 636                 return;
 637
 638         /* this module generate empty packet for 'no data' */
 639         if (!(s->flags & CIP_BLOCKING) || (syt != CIP_SYT_NO_INFO))
 640                 data_blocks = calculate_data_blocks(s);
 641         else
 642                 data_blocks = 0;
 643
 644         buffer = s->buffer.packets[s->packet_index].buffer;
 645         buffer[0] = cpu_to_be32(ACCESS_ONCE(s->source_node_id_field) |
 646                                 (s->data_block_quadlets << AMDTP_DBS_SHIFT) |
 647                                 s->data_block_counter);
 648         buffer[1] = cpu_to_be32(CIP_EOH | CIP_FMT_AM | AMDTP_FDF_AM824 |
 649                                 (s->sfc << CIP_FDF_SFC_SHIFT) | syt);
 650         buffer += 2;
 651
 652         pcm = ACCESS_ONCE(s->pcm);
 653         if (pcm)
 654                 s->transfer_samples(s, pcm, buffer, data_blocks);
 655         else
 656                 amdtp_fill_pcm_silence(s, buffer, data_blocks);
 657         if (s->midi_ports)
 658                 amdtp_fill_midi(s, buffer, data_blocks);
 659
 660         s->data_block_counter = (s->data_block_counter + data_blocks) & 0xff;
 661
 662         payload_length = 8 + data_blocks * 4 * s->data_block_quadlets;
 663         if (queue_out_packet(s, payload_length, false) < 0) {
 664                 s->packet_index = -1;
 665                 amdtp_stream_pcm_abort(s);
 666                 return;
 667         }
 668
 669         if (pcm)
 670                 update_pcm_pointers(s, pcm, data_blocks);
 671 }
 672
 673 static void handle_in_packet(struct amdtp_stream *s,
 674                              unsigned int payload_quadlets,
 675                              __be32 *buffer)
 676 {
 677         u32 cip_header[2];
 678         unsigned int data_blocks, data_block_quadlets, data_block_counter;
 679         struct snd_pcm_substream *pcm = NULL;
 680
 681         cip_header[0] = be32_to_cpu(buffer[0]);
 682         cip_header[1] = be32_to_cpu(buffer[1]);
 683
 684         /*
 685          * This module supports 'Two-quadlet CIP header with SYT field'.
 686          * For convinience, also check FMT field is AM824 or not.
 687          */
 688         if (((cip_header[0] & CIP_EOH_MASK) == CIP_EOH) ||
 689             ((cip_header[1] & CIP_EOH_MASK) != CIP_EOH) ||
 690             ((cip_header[1] & CIP_FMT_MASK) != CIP_FMT_AM)) {
 691                 dev_info_ratelimited(&s->unit->device,
 692                                 "Invalid CIP header for AMDTP: %08X:%08X\n",
 693                                 cip_header[0], cip_header[1]);
 694                 goto end;
 695         }
 696
 697         /* Calculate data blocks */
 698         if (payload_quadlets < 3 ||
 699             ((cip_header[1] & CIP_FDF_MASK) ==
 700                                 (AMDTP_FDF_NO_DATA << CIP_FDF_SFC_SHIFT))) {
 701                 data_blocks = 0;
 702         } else {
 703                 data_block_quadlets =
 704                         (cip_header[0] & AMDTP_DBS_MASK) >> AMDTP_DBS_SHIFT;
 705                 /* avoid division by zero */
 706                 if (data_block_quadlets == 0) {
 707                         dev_info_ratelimited(&s->unit->device,
 708                                 "Detect invalid value in dbs field: %08X\n",
 709                                 cip_header[0]);
 710                         goto err;
 711                 }
 712
 713                 data_blocks = (payload_quadlets - 2) / data_block_quadlets;
 714         }
 715
 716         /* Check data block counter continuity */
 717         data_block_counter = cip_header[0] & AMDTP_DBC_MASK;
 718         if (data_block_counter != s->data_block_counter) {
 719                 dev_info(&s->unit->device,
 720                          "Detect discontinuity of CIP: %02X %02X\n",
 721                          s->data_block_counter, data_block_counter);
 722                 goto err;
 723         }
 724
 725         if (data_blocks > 0) {
 726                 buffer += 2;
 727
 728                 pcm = ACCESS_ONCE(s->pcm);
 729                 if (pcm)
 730                         s->transfer_samples(s, pcm, buffer, data_blocks);
 731
 732                 if (s->midi_ports)
 733                         amdtp_pull_midi(s, buffer, data_blocks);
 734         }
 735
 736         s->data_block_counter = (data_block_counter + data_blocks) & 0xff;
 737 end:
 738         if (queue_in_packet(s) < 0)
 739                 goto err;
 740
 741         if (pcm)
 742                 update_pcm_pointers(s, pcm, data_blocks);
 743
 744         return;
 745 err:
 746         s->packet_index = -1;
 747         amdtp_stream_pcm_abort(s);
 748 }
 749
 750 static void out_stream_callback(struct fw_iso_context *context, u32 cycle,
 751                                 size_t header_length, void *header,
 752                                 void *private_data)
 753 {
 754         struct amdtp_stream *s = private_data;
 755         unsigned int i, syt, packets = header_length / 4;
 756
 757         /*
 758          * Compute the cycle of the last queued packet.
 759          * (We need only the four lowest bits for the SYT, so we can ignore
 760          * that bits 0-11 must wrap around at 3072.)
 761          */
 762         cycle += QUEUE_LENGTH - packets;
 763
 764         for (i = 0; i < packets; ++i) {
 765                 syt = calculate_syt(s, ++cycle);
 766                 handle_out_packet(s, syt);
 767         }
 768         fw_iso_context_queue_flush(s->context);
 769 }
 770
 771 static void in_stream_callback(struct fw_iso_context *context, u32 cycle,
 772                                size_t header_length, void *header,
 773                                void *private_data)
 774 {
 775         struct amdtp_stream *s = private_data;
 776         unsigned int p, syt, packets, payload_quadlets;
 777         __be32 *buffer, *headers = header;
 778
 779         /* The number of packets in buffer */
 780         packets = header_length / IN_PACKET_HEADER_SIZE;
 781
 782         for (p = 0; p < packets; p++) {
 783                 if (s->packet_index < 0)
 784                         break;
 785
 786                 buffer = s->buffer.packets[s->packet_index].buffer;
 787
 788                 /* Process sync slave stream */
 789                 if (s->sync_slave && s->sync_slave->callbacked) {
 790                         syt = be32_to_cpu(buffer[1]) & CIP_SYT_MASK;
 791                         handle_out_packet(s->sync_slave, syt);
 792                 }
 793
 794                 /* The number of quadlets in this packet */
 795                 payload_quadlets =
 796                         (be32_to_cpu(headers[p]) >> ISO_DATA_LENGTH_SHIFT) / 4;
 797                 handle_in_packet(s, payload_quadlets, buffer);
 798         }
 799
 800         /* Queueing error or detecting discontinuity */
 801         if (s->packet_index < 0) {
 802                 /* Abort sync slave. */
 803                 if (s->sync_slave) {
 804                         s->sync_slave->packet_index = -1;
 805                         amdtp_stream_pcm_abort(s->sync_slave);
 806                 }
 807                 return;
 808         }
 809
 810         /* when sync to device, flush the packets for slave stream */
 811         if (s->sync_slave && s->sync_slave->callbacked)
 812                 fw_iso_context_queue_flush(s->sync_slave->context);
 813
 814         fw_iso_context_queue_flush(s->context);
 815 }
 816
 817 /* processing is done by master callback */
 818 static void slave_stream_callback(struct fw_iso_context *context, u32 cycle,
 819                                   size_t header_length, void *header,
 820                                   void *private_data)
 821 {
 822         return;
 823 }
 824
 825 /* this is executed one time */
 826 static void amdtp_stream_first_callback(struct fw_iso_context *context,
 827                                         u32 cycle, size_t header_length,
 828                                         void *header, void *private_data)
 829 {
 830         struct amdtp_stream *s = private_data;
 831
 832         /*
 833          * For in-stream, first packet has come.
 834          * For out-stream, prepared to transmit first packet
 835          */
 836         s->callbacked = true;
 837         wake_up(&s->callback_wait);
 838
 839         if (s->direction == AMDTP_IN_STREAM)
 840                 context->callback.sc = in_stream_callback;
 841         else if ((s->flags & CIP_BLOCKING) && (s->flags & CIP_SYNC_TO_DEVICE))
 842                 context->callback.sc = slave_stream_callback;
 843         else
 844                 context->callback.sc = out_stream_callback;
 845
 846         context->callback.sc(context, cycle, header_length, header, s);
 847 }
 848
 849 /**
 850  * amdtp_stream_start - start transferring packets
 851  * @s: the AMDTP stream to start
 852  * @channel: the isochronous channel on the bus
 853  * @speed: firewire speed code
 854  *
 855  * The stream cannot be started until it has been configured with
 856  * amdtp_stream_set_parameters() and it must be started before any PCM or MIDI
 857  * device can be started.
 858  */
 859 int amdtp_stream_start(struct amdtp_stream *s, int channel, int speed)
 860 {
 861         static const struct {
 862                 unsigned int data_block;
 863                 unsigned int syt_offset;
 864         } initial_state[] = {
 865                 [CIP_SFC_32000]  = {  4, 3072 },
 866                 [CIP_SFC_48000]  = {  6, 1024 },
 867                 [CIP_SFC_96000]  = { 12, 1024 },
 868                 [CIP_SFC_192000] = { 24, 1024 },
 869                 [CIP_SFC_44100]  = {  0,   67 },
 870                 [CIP_SFC_88200]  = {  0,   67 },
 871                 [CIP_SFC_176400] = {  0,   67 },
 872         };
 873         unsigned int header_size;
 874         enum dma_data_direction dir;
 875         int type, err;
 876
 877         mutex_lock(&s->mutex);
 878
 879         if (WARN_ON(amdtp_stream_running(s) ||
 880                     (s->data_block_quadlets < 1))) {
 881                 err = -EBADFD;
 882                 goto err_unlock;
 883         }
 884
 885         s->data_block_counter = 0;
 886         s->data_block_state = initial_state[s->sfc].data_block;
 887         s->syt_offset_state = initial_state[s->sfc].syt_offset;
 888         s->last_syt_offset = TICKS_PER_CYCLE;
 889
 890         /* initialize packet buffer */
 891         if (s->direction == AMDTP_IN_STREAM) {
 892                 dir = DMA_FROM_DEVICE;
 893                 type = FW_ISO_CONTEXT_RECEIVE;
 894                 header_size = IN_PACKET_HEADER_SIZE;
 895         } else {
 896                 dir = DMA_TO_DEVICE;
 897                 type = FW_ISO_CONTEXT_TRANSMIT;
 898                 header_size = OUT_PACKET_HEADER_SIZE;
 899         }
 900         err = iso_packets_buffer_init(&s->buffer, s->unit, QUEUE_LENGTH,
 901                                       amdtp_stream_get_max_payload(s), dir);
 902         if (err < 0)
 903                 goto err_unlock;
 904
 905         s->context = fw_iso_context_create(fw_parent_device(s->unit)->card,
 906                                            type, channel, speed, header_size,
 907                                            amdtp_stream_first_callback, s);
 908         if (IS_ERR(s->context)) {
 909                 err = PTR_ERR(s->context);
 910                 if (err == -EBUSY)
 911                         dev_err(&s->unit->device,
 912                                 "no free stream on this controller\n");
 913                 goto err_buffer;
 914         }
 915
 916         amdtp_stream_update(s);
 917
 918         s->packet_index = 0;
 919         do {
 920                 if (s->direction == AMDTP_IN_STREAM)
 921                         err = queue_in_packet(s);
 922                 else
 923                         err = queue_out_packet(s, 0, true);
 924                 if (err < 0)
 925                         goto err_context;
 926         } while (s->packet_index > 0);
 927
 928         /* NOTE: TAG1 matches CIP. This just affects in stream. */
 929         s->callbacked = false;
 930         err = fw_iso_context_start(s->context, -1, 0,
 931                                    FW_ISO_CONTEXT_MATCH_TAG1);
 932         if (err < 0)
 933                 goto err_context;
 934
 935         mutex_unlock(&s->mutex);
 936
 937         return 0;
 938
 939 err_context:
 940         fw_iso_context_destroy(s->context);
 941         s->context = ERR_PTR(-1);
 942 err_buffer:
 943         iso_packets_buffer_destroy(&s->buffer, s->unit);
 944 err_unlock:
 945         mutex_unlock(&s->mutex);
 946
 947         return err;
 948 }
 949 EXPORT_SYMBOL(amdtp_stream_start);
 950
 951 /**
 952  * amdtp_stream_pcm_pointer - get the PCM buffer position
 953  * @s: the AMDTP stream that transports the PCM data
 954  *
 955  * Returns the current buffer position, in frames.
 956  */
 957 unsigned long amdtp_stream_pcm_pointer(struct amdtp_stream *s)
 958 {
 959         /* this optimization is allowed to be racy */
 960         if (s->pointer_flush)
 961                 fw_iso_context_flush_completions(s->context);
 962         else
 963                 s->pointer_flush = true;
 964
 965         return ACCESS_ONCE(s->pcm_buffer_pointer);
 966 }
 967 EXPORT_SYMBOL(amdtp_stream_pcm_pointer);
 968
 969 /**
 970  * amdtp_stream_update - update the stream after a bus reset
 971  * @s: the AMDTP stream
 972  */
 973 void amdtp_stream_update(struct amdtp_stream *s)
 974 {
 975         ACCESS_ONCE(s->source_node_id_field) =
 976                 (fw_parent_device(s->unit)->card->node_id & 0x3f) << 24;
 977 }
 978 EXPORT_SYMBOL(amdtp_stream_update);
 979
 980 /**
 981  * amdtp_stream_stop - stop sending packets
 982  * @s: the AMDTP stream to stop
 983  *
 984  * All PCM and MIDI devices of the stream must be stopped before the stream
 985  * itself can be stopped.
 986  */
 987 void amdtp_stream_stop(struct amdtp_stream *s)
 988 {
 989         mutex_lock(&s->mutex);
 990
 991         if (!amdtp_stream_running(s)) {
 992                 mutex_unlock(&s->mutex);
 993                 return;
 994         }
 995
 996         tasklet_kill(&s->period_tasklet);
 997         fw_iso_context_stop(s->context);
 998         fw_iso_context_destroy(s->context);
 999         s->context = ERR_PTR(-1);
1000         iso_packets_buffer_destroy(&s->buffer, s->unit);
1001
1002         s->callbacked = false;
1003
1004         mutex_unlock(&s->mutex);
1005 }
1006 EXPORT_SYMBOL(amdtp_stream_stop);
1007
1008 /**
1009  * amdtp_stream_pcm_abort - abort the running PCM device
1010  * @s: the AMDTP stream about to be stopped
1011  *
1012  * If the isochronous stream needs to be stopped asynchronously, call this
1013  * function first to stop the PCM device.
1014  */
1015 void amdtp_stream_pcm_abort(struct amdtp_stream *s)
1016 {
1017         struct snd_pcm_substream *pcm;
1018
1019         pcm = ACCESS_ONCE(s->pcm);
1020         if (pcm) {
1021                 snd_pcm_stream_lock_irq(pcm);
1022                 if (snd_pcm_running(pcm))
1023                         snd_pcm_stop(pcm, SNDRV_PCM_STATE_XRUN);
1024                 snd_pcm_stream_unlock_irq(pcm);
1025         }
1026 }
1027 EXPORT_SYMBOL(amdtp_stream_pcm_abort);