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/pcm_params.h>
  17 #include <sound/rawmidi.h>
  18 #include "amdtp.h"
  19
  20 #define TICKS_PER_CYCLE         3072
  21 #define CYCLES_PER_SECOND       8000
  22 #define TICKS_PER_SECOND        (TICKS_PER_CYCLE * CYCLES_PER_SECOND)
  23
  24 #define TRANSFER_DELAY_TICKS    0x2e00 /* 479.17 µs */
  25
  26 /* isochronous header parameters */
  27 #define ISO_DATA_LENGTH_SHIFT   16
  28 #define TAG_CIP                 1
  29
  30 /* common isochronous packet header parameters */
  31 #define CIP_EOH                 (1u << 31)
  32 #define CIP_EOH_MASK            0x80000000
  33 #define CIP_FMT_AM              (0x10 << 24)
  34 #define CIP_FMT_MASK            0x3f000000
  35 #define CIP_SYT_MASK            0x0000ffff
  36 #define CIP_SYT_NO_INFO         0xffff
  37 #define CIP_FDF_MASK            0x00ff0000
  38 #define CIP_FDF_SFC_SHIFT       16
  39
  40 /*
  41  * Audio and Music transfer protocol specific parameters
  42  * only "Clock-based rate control mode" is supported
  43  */
  44 #define AMDTP_FDF_AM824         (0 << (CIP_FDF_SFC_SHIFT + 3))
  45 #define AMDTP_FDF_NO_DATA       0xff
  46 #define AMDTP_DBS_MASK          0x00ff0000
  47 #define AMDTP_DBS_SHIFT         16
  48 #define AMDTP_DBC_MASK          0x000000ff
  49
  50 /* TODO: make these configurable */
  51 #define INTERRUPT_INTERVAL      16
  52 #define QUEUE_LENGTH            48
  53
  54 #define IN_PACKET_HEADER_SIZE   4
  55 #define OUT_PACKET_HEADER_SIZE  0
  56
  57 static void pcm_period_tasklet(unsigned long data);
  58
  59 /**
  60  * amdtp_stream_init - initialize an AMDTP stream structure
  61  * @s: the AMDTP stream to initialize
  62  * @unit: the target of the stream
  63  * @dir: the direction of stream
  64  * @flags: the packet transmission method to use
  65  */
  66 int amdtp_stream_init(struct amdtp_stream *s, struct fw_unit *unit,
  67                       enum amdtp_stream_direction dir, enum cip_flags flags)
  68 {
  69         s->unit = fw_unit_get(unit);
  70         s->direction = dir;
  71         s->flags = flags;
  72         s->context = ERR_PTR(-1);
  73         mutex_init(&s->mutex);
  74         tasklet_init(&s->period_tasklet, pcm_period_tasklet, (unsigned long)s);
  75         s->packet_index = 0;
  76
  77         init_waitqueue_head(&s->callback_wait);
  78         s->callbacked = false;
  79         s->sync_slave = NULL;
  80
  81         return 0;
  82 }
  83 EXPORT_SYMBOL(amdtp_stream_init);
  84
  85 /**
  86  * amdtp_stream_destroy - free stream resources
  87  * @s: the AMDTP stream to destroy
  88  */
  89 void amdtp_stream_destroy(struct amdtp_stream *s)
  90 {
  91         WARN_ON(amdtp_stream_running(s));
  92         mutex_destroy(&s->mutex);
  93         fw_unit_put(s->unit);
  94 }
  95 EXPORT_SYMBOL(amdtp_stream_destroy);
  96
  97 const unsigned int amdtp_syt_intervals[CIP_SFC_COUNT] = {
  98         [CIP_SFC_32000]  =  8,
  99         [CIP_SFC_44100]  =  8,
 100         [CIP_SFC_48000]  =  8,
 101         [CIP_SFC_88200]  = 16,
 102         [CIP_SFC_96000]  = 16,
 103         [CIP_SFC_176400] = 32,
 104         [CIP_SFC_192000] = 32,
 105 };
 106 EXPORT_SYMBOL(amdtp_syt_intervals);
 107
 108 const unsigned int amdtp_rate_table[] = {
 109         [CIP_SFC_32000]  =  32000,
 110         [CIP_SFC_44100]  =  44100,
 111         [CIP_SFC_48000]  =  48000,
 112         [CIP_SFC_88200]  =  88200,
 113         [CIP_SFC_96000]  =  96000,
 114         [CIP_SFC_176400] = 176400,
 115         [CIP_SFC_192000] = 192000,
 116 };
 117 EXPORT_SYMBOL(amdtp_rate_table);
 118
 119 /**
 120  * amdtp_stream_add_pcm_hw_constraints - add hw constraints for PCM substream
 121  * @s:          the AMDTP stream, which must be initialized.
 122  * @runtime:    the PCM substream runtime
 123  */
 124 int amdtp_stream_add_pcm_hw_constraints(struct amdtp_stream *s,
 125                                         struct snd_pcm_runtime *runtime)
 126 {
 127         int err;
 128
 129         /* AM824 in IEC 61883-6 can deliver 24bit data */
 130         err = snd_pcm_hw_constraint_msbits(runtime, 0, 32, 24);
 131         if (err < 0)
 132                 goto end;
 133
 134         /*
 135          * Currently firewire-lib processes 16 packets in one software
 136          * interrupt callback. This equals to 2msec but actually the
 137          * interval of the interrupts has a jitter.
 138          * Additionally, even if adding a constraint to fit period size to
 139          * 2msec, actual calculated frames per period doesn't equal to 2msec,
 140          * depending on sampling rate.
 141          * Anyway, the interval to call snd_pcm_period_elapsed() cannot 2msec.
 142          * Here let us use 5msec for safe period interrupt.
 143          */
 144         err = snd_pcm_hw_constraint_minmax(runtime,
 145                                            SNDRV_PCM_HW_PARAM_PERIOD_TIME,
 146                                            5000, UINT_MAX);
 147         if (err < 0)
 148                 goto end;
 149
 150         /* Non-Blocking stream has no more constraints */
 151         if (!(s->flags & CIP_BLOCKING))
 152                 goto end;
 153
 154         /*
 155          * One AMDTP packet can include some frames. In blocking mode, the
 156          * number equals to SYT_INTERVAL. So the number is 8, 16 or 32,
 157          * depending on its sampling rate. For accurate period interrupt, it's
 158          * preferrable to aligh period/buffer sizes to current SYT_INTERVAL.
 159          *
 160          * TODO: These constraints can be improved with propper rules.
 161          * Currently apply LCM of SYT_INTEVALs.
 162          */
 163         err = snd_pcm_hw_constraint_step(runtime, 0,
 164                                          SNDRV_PCM_HW_PARAM_PERIOD_SIZE, 32);
 165         if (err < 0)
 166                 goto end;
 167         err = snd_pcm_hw_constraint_step(runtime, 0,
 168                                          SNDRV_PCM_HW_PARAM_BUFFER_SIZE, 32);
 169 end:
 170         return err;
 171 }
 172 EXPORT_SYMBOL(amdtp_stream_add_pcm_hw_constraints);
 173
 174 /**
 175  * amdtp_stream_set_parameters - set stream parameters
 176  * @s: the AMDTP stream to configure
 177  * @rate: the sample rate
 178  * @pcm_channels: the number of PCM samples in each data block, to be encoded
 179  *                as AM824 multi-bit linear audio
 180  * @midi_ports: the number of MIDI ports (i.e., MPX-MIDI Data Channels)
 181  *
 182  * The parameters must be set before the stream is started, and must not be
 183  * changed while the stream is running.
 184  */
 185 void amdtp_stream_set_parameters(struct amdtp_stream *s,
 186                                  unsigned int rate,
 187                                  unsigned int pcm_channels,
 188                                  unsigned int midi_ports)
 189 {
 190         unsigned int i, sfc, midi_channels;
 191
 192         midi_channels = DIV_ROUND_UP(midi_ports, 8);
 193
 194         if (WARN_ON(amdtp_stream_running(s)) |
 195             WARN_ON(pcm_channels > AMDTP_MAX_CHANNELS_FOR_PCM) |
 196             WARN_ON(midi_channels > AMDTP_MAX_CHANNELS_FOR_MIDI))
 197                 return;
 198
 199         for (sfc = 0; sfc < sizeof(amdtp_rate_table); ++sfc)
 200                 if (amdtp_rate_table[sfc] == rate)
 201                         goto sfc_found;
 202         WARN_ON(1);
 203         return;
 204
 205 sfc_found:
 206         s->pcm_channels = pcm_channels;
 207         s->sfc = sfc;
 208         s->data_block_quadlets = s->pcm_channels + midi_channels;
 209         s->midi_ports = midi_ports;
 210
 211         s->syt_interval = amdtp_syt_intervals[sfc];
 212
 213         /* default buffering in the device */
 214         s->transfer_delay = TRANSFER_DELAY_TICKS - TICKS_PER_CYCLE;
 215         if (s->flags & CIP_BLOCKING)
 216                 /* additional buffering needed to adjust for no-data packets */
 217                 s->transfer_delay += TICKS_PER_SECOND * s->syt_interval / rate;
 218
 219         /* init the position map for PCM and MIDI channels */
 220         for (i = 0; i < pcm_channels; i++)
 221                 s->pcm_positions[i] = i;
 222         s->midi_position = s->pcm_channels;
 223 }
 224 EXPORT_SYMBOL(amdtp_stream_set_parameters);
 225
 226 /**
 227  * amdtp_stream_get_max_payload - get the stream's packet size
 228  * @s: the AMDTP stream
 229  *
 230  * This function must not be called before the stream has been configured
 231  * with amdtp_stream_set_parameters().
 232  */
 233 unsigned int amdtp_stream_get_max_payload(struct amdtp_stream *s)
 234 {
 235         return 8 + s->syt_interval * s->data_block_quadlets * 4;
 236 }
 237 EXPORT_SYMBOL(amdtp_stream_get_max_payload);
 238
 239 static void amdtp_write_s16(struct amdtp_stream *s,
 240                             struct snd_pcm_substream *pcm,
 241                             __be32 *buffer, unsigned int frames);
 242 static void amdtp_write_s32(struct amdtp_stream *s,
 243                             struct snd_pcm_substream *pcm,
 244                             __be32 *buffer, unsigned int frames);
 245 static void amdtp_read_s32(struct amdtp_stream *s,
 246                            struct snd_pcm_substream *pcm,
 247                            __be32 *buffer, unsigned int frames);
 248
 249 /**
 250  * amdtp_stream_set_pcm_format - set the PCM format
 251  * @s: the AMDTP stream to configure
 252  * @format: the format of the ALSA PCM device
 253  *
 254  * The sample format must be set after the other paramters (rate/PCM channels/
 255  * MIDI) and before the stream is started, and must not be changed while the
 256  * stream is running.
 257  */
 258 void amdtp_stream_set_pcm_format(struct amdtp_stream *s,
 259                                  snd_pcm_format_t format)
 260 {
 261         if (WARN_ON(amdtp_stream_pcm_running(s)))
 262                 return;
 263
 264         switch (format) {
 265         default:
 266                 WARN_ON(1);
 267                 /* fall through */
 268         case SNDRV_PCM_FORMAT_S16:
 269                 if (s->direction == AMDTP_OUT_STREAM) {
 270                         s->transfer_samples = amdtp_write_s16;
 271                         break;
 272                 }
 273                 WARN_ON(1);
 274                 /* fall through */
 275         case SNDRV_PCM_FORMAT_S32:
 276                 if (s->direction == AMDTP_OUT_STREAM)
 277                         s->transfer_samples = amdtp_write_s32;
 278                 else
 279                         s->transfer_samples = amdtp_read_s32;
 280                 break;
 281         }
 282 }
 283 EXPORT_SYMBOL(amdtp_stream_set_pcm_format);
 284
 285 /**
 286  * amdtp_stream_pcm_prepare - prepare PCM device for running
 287  * @s: the AMDTP stream
 288  *
 289  * This function should be called from the PCM device's .prepare callback.
 290  */
 291 void amdtp_stream_pcm_prepare(struct amdtp_stream *s)
 292 {
 293         tasklet_kill(&s->period_tasklet);
 294         s->pcm_buffer_pointer = 0;
 295         s->pcm_period_pointer = 0;
 296         s->pointer_flush = true;
 297 }
 298 EXPORT_SYMBOL(amdtp_stream_pcm_prepare);
 299
 300 static unsigned int calculate_data_blocks(struct amdtp_stream *s)
 301 {
 302         unsigned int phase, data_blocks;
 303
 304         if (s->flags & CIP_BLOCKING)
 305                 data_blocks = s->syt_interval;
 306         else if (!cip_sfc_is_base_44100(s->sfc)) {
 307                 /* Sample_rate / 8000 is an integer, and precomputed. */
 308                 data_blocks = s->data_block_state;
 309         } else {
 310                 phase = s->data_block_state;
 311
 312                 /*
 313                  * This calculates the number of data blocks per packet so that
 314                  * 1) the overall rate is correct and exactly synchronized to
 315                  *    the bus clock, and
 316                  * 2) packets with a rounded-up number of blocks occur as early
 317                  *    as possible in the sequence (to prevent underruns of the
 318                  *    device's buffer).
 319                  */
 320                 if (s->sfc == CIP_SFC_44100)
 321                         /* 6 6 5 6 5 6 5 ... */
 322                         data_blocks = 5 + ((phase & 1) ^
 323                                            (phase == 0 || phase >= 40));
 324                 else
 325                         /* 12 11 11 11 11 ... or 23 22 22 22 22 ... */
 326                         data_blocks = 11 * (s->sfc >> 1) + (phase == 0);
 327                 if (++phase >= (80 >> (s->sfc >> 1)))
 328                         phase = 0;
 329                 s->data_block_state = phase;
 330         }
 331
 332         return data_blocks;
 333 }
 334
 335 static unsigned int calculate_syt(struct amdtp_stream *s,
 336                                   unsigned int cycle)
 337 {
 338         unsigned int syt_offset, phase, index, syt;
 339
 340         if (s->last_syt_offset < TICKS_PER_CYCLE) {
 341                 if (!cip_sfc_is_base_44100(s->sfc))
 342                         syt_offset = s->last_syt_offset + s->syt_offset_state;
 343                 else {
 344                 /*
 345                  * The time, in ticks, of the n'th SYT_INTERVAL sample is:
 346                  *   n * SYT_INTERVAL * 24576000 / sample_rate
 347                  * Modulo TICKS_PER_CYCLE, the difference between successive
 348                  * elements is about 1386.23.  Rounding the results of this
 349                  * formula to the SYT precision results in a sequence of
 350                  * differences that begins with:
 351                  *   1386 1386 1387 1386 1386 1386 1387 1386 1386 1386 1387 ...
 352                  * This code generates _exactly_ the same sequence.
 353                  */
 354                         phase = s->syt_offset_state;
 355                         index = phase % 13;
 356                         syt_offset = s->last_syt_offset;
 357                         syt_offset += 1386 + ((index && !(index & 3)) ||
 358                                               phase == 146);
 359                         if (++phase >= 147)
 360                                 phase = 0;
 361                         s->syt_offset_state = phase;
 362                 }
 363         } else
 364                 syt_offset = s->last_syt_offset - TICKS_PER_CYCLE;
 365         s->last_syt_offset = syt_offset;
 366
 367         if (syt_offset < TICKS_PER_CYCLE) {
 368                 syt_offset += s->transfer_delay;
 369                 syt = (cycle + syt_offset / TICKS_PER_CYCLE) << 12;
 370                 syt += syt_offset % TICKS_PER_CYCLE;
 371
 372                 return syt & CIP_SYT_MASK;
 373         } else {
 374                 return CIP_SYT_NO_INFO;
 375         }
 376 }
 377
 378 static void amdtp_write_s32(struct amdtp_stream *s,
 379                             struct snd_pcm_substream *pcm,
 380                             __be32 *buffer, unsigned int frames)
 381 {
 382         struct snd_pcm_runtime *runtime = pcm->runtime;
 383         unsigned int channels, remaining_frames, i, c;
 384         const u32 *src;
 385
 386         channels = s->pcm_channels;
 387         src = (void *)runtime->dma_area +
 388                         frames_to_bytes(runtime, s->pcm_buffer_pointer);
 389         remaining_frames = runtime->buffer_size - s->pcm_buffer_pointer;
 390
 391         for (i = 0; i < frames; ++i) {
 392                 for (c = 0; c < channels; ++c) {
 393                         buffer[s->pcm_positions[c]] =
 394                                         cpu_to_be32((*src >> 8) | 0x40000000);
 395                         src++;
 396                 }
 397                 buffer += s->data_block_quadlets;
 398                 if (--remaining_frames == 0)
 399                         src = (void *)runtime->dma_area;
 400         }
 401 }
 402
 403 static void amdtp_write_s16(struct amdtp_stream *s,
 404                             struct snd_pcm_substream *pcm,
 405                             __be32 *buffer, unsigned int frames)
 406 {
 407         struct snd_pcm_runtime *runtime = pcm->runtime;
 408         unsigned int channels, remaining_frames, i, c;
 409         const u16 *src;
 410
 411         channels = s->pcm_channels;
 412         src = (void *)runtime->dma_area +
 413                         frames_to_bytes(runtime, s->pcm_buffer_pointer);
 414         remaining_frames = runtime->buffer_size - s->pcm_buffer_pointer;
 415
 416         for (i = 0; i < frames; ++i) {
 417                 for (c = 0; c < channels; ++c) {
 418                         buffer[s->pcm_positions[c]] =
 419                                         cpu_to_be32((*src << 8) | 0x40000000);
 420                         src++;
 421                 }
 422                 buffer += s->data_block_quadlets;
 423                 if (--remaining_frames == 0)
 424                         src = (void *)runtime->dma_area;
 425         }
 426 }
 427
 428 static void amdtp_read_s32(struct amdtp_stream *s,
 429                            struct snd_pcm_substream *pcm,
 430                            __be32 *buffer, unsigned int frames)
 431 {
 432         struct snd_pcm_runtime *runtime = pcm->runtime;
 433         unsigned int channels, remaining_frames, i, c;
 434         u32 *dst;
 435
 436         channels = s->pcm_channels;
 437         dst  = (void *)runtime->dma_area +
 438                         frames_to_bytes(runtime, s->pcm_buffer_pointer);
 439         remaining_frames = runtime->buffer_size - s->pcm_buffer_pointer;
 440
 441         for (i = 0; i < frames; ++i) {
 442                 for (c = 0; c < channels; ++c) {
 443                         *dst = be32_to_cpu(buffer[s->pcm_positions[c]]) << 8;
 444                         dst++;
 445                 }
 446                 buffer += s->data_block_quadlets;
 447                 if (--remaining_frames == 0)
 448                         dst = (void *)runtime->dma_area;
 449         }
 450 }
 451
 452 static void amdtp_fill_pcm_silence(struct amdtp_stream *s,
 453                                    __be32 *buffer, unsigned int frames)
 454 {
 455         unsigned int i, c;
 456
 457         for (i = 0; i < frames; ++i) {
 458                 for (c = 0; c < s->pcm_channels; ++c)
 459                         buffer[s->pcm_positions[c]] = cpu_to_be32(0x40000000);
 460                 buffer += s->data_block_quadlets;
 461         }
 462 }
 463
 464 static void amdtp_fill_midi(struct amdtp_stream *s,
 465                             __be32 *buffer, unsigned int frames)
 466 {
 467         unsigned int f, port;
 468         u8 *b;
 469
 470         for (f = 0; f < frames; f++) {
 471                 buffer[s->midi_position] = 0;
 472                 b = (u8 *)&buffer[s->midi_position];
 473
 474                 port = (s->data_block_counter + f) % 8;
 475                 if ((s->midi[port] == NULL) ||
 476                     (snd_rawmidi_transmit(s->midi[port], b + 1, 1) <= 0))
 477                         b[0] = 0x80;
 478                 else
 479                         b[0] = 0x81;
 480
 481                 buffer += s->data_block_quadlets;
 482         }
 483 }
 484
 485 static void amdtp_pull_midi(struct amdtp_stream *s,
 486                             __be32 *buffer, unsigned int frames)
 487 {
 488         unsigned int f, port;
 489         int len;
 490         u8 *b;
 491
 492         for (f = 0; f < frames; f++) {
 493                 port = (s->data_block_counter + f) % 8;
 494                 b = (u8 *)&buffer[s->midi_position];
 495
 496                 len = b[0] - 0x80;
 497                 if ((1 <= len) &&  (len <= 3) && (s->midi[port]))
 498                         snd_rawmidi_receive(s->midi[port], b + 1, len);
 499
 500                 buffer += s->data_block_quadlets;
 501         }
 502 }
 503
 504 static void update_pcm_pointers(struct amdtp_stream *s,
 505                                 struct snd_pcm_substream *pcm,
 506                                 unsigned int frames)
 507 {       unsigned int ptr;
 508
 509         ptr = s->pcm_buffer_pointer + frames;
 510         if (ptr >= pcm->runtime->buffer_size)
 511                 ptr -= pcm->runtime->buffer_size;
 512         ACCESS_ONCE(s->pcm_buffer_pointer) = ptr;
 513
 514         s->pcm_period_pointer += frames;
 515         if (s->pcm_period_pointer >= pcm->runtime->period_size) {
 516                 s->pcm_period_pointer -= pcm->runtime->period_size;
 517                 s->pointer_flush = false;
 518                 tasklet_hi_schedule(&s->period_tasklet);
 519         }
 520 }
 521
 522 static void pcm_period_tasklet(unsigned long data)
 523 {
 524         struct amdtp_stream *s = (void *)data;
 525         struct snd_pcm_substream *pcm = ACCESS_ONCE(s->pcm);
 526
 527         if (pcm)
 528                 snd_pcm_period_elapsed(pcm);
 529 }
 530
 531 static int queue_packet(struct amdtp_stream *s,
 532                         unsigned int header_length,
 533                         unsigned int payload_length, bool skip)
 534 {
 535         struct fw_iso_packet p = {0};
 536         int err = 0;
 537
 538         if (IS_ERR(s->context))
 539                 goto end;
 540
 541         p.interrupt = IS_ALIGNED(s->packet_index + 1, INTERRUPT_INTERVAL);
 542         p.tag = TAG_CIP;
 543         p.header_length = header_length;
 544         p.payload_length = (!skip) ? payload_length : 0;
 545         p.skip = skip;
 546         err = fw_iso_context_queue(s->context, &p, &s->buffer.iso_buffer,
 547                                    s->buffer.packets[s->packet_index].offset);
 548         if (err < 0) {
 549                 dev_err(&s->unit->device, "queueing error: %d\n", err);
 550                 goto end;
 551         }
 552
 553         if (++s->packet_index >= QUEUE_LENGTH)
 554                 s->packet_index = 0;
 555 end:
 556         return err;
 557 }
 558
 559 static inline int queue_out_packet(struct amdtp_stream *s,
 560                                    unsigned int payload_length, bool skip)
 561 {
 562         return queue_packet(s, OUT_PACKET_HEADER_SIZE,
 563                             payload_length, skip);
 564 }
 565
 566 static inline int queue_in_packet(struct amdtp_stream *s)
 567 {
 568         return queue_packet(s, IN_PACKET_HEADER_SIZE,
 569                             amdtp_stream_get_max_payload(s), false);
 570 }
 571
 572 static void handle_out_packet(struct amdtp_stream *s, unsigned int syt)
 573 {
 574         __be32 *buffer;
 575         unsigned int data_blocks, payload_length;
 576         struct snd_pcm_substream *pcm;
 577
 578         if (s->packet_index < 0)
 579                 return;
 580
 581         /* this module generate empty packet for 'no data' */
 582         if (!(s->flags & CIP_BLOCKING) || (syt != CIP_SYT_NO_INFO))
 583                 data_blocks = calculate_data_blocks(s);
 584         else
 585                 data_blocks = 0;
 586
 587         buffer = s->buffer.packets[s->packet_index].buffer;
 588         buffer[0] = cpu_to_be32(ACCESS_ONCE(s->source_node_id_field) |
 589                                 (s->data_block_quadlets << AMDTP_DBS_SHIFT) |
 590                                 s->data_block_counter);
 591         buffer[1] = cpu_to_be32(CIP_EOH | CIP_FMT_AM | AMDTP_FDF_AM824 |
 592                                 (s->sfc << CIP_FDF_SFC_SHIFT) | syt);
 593         buffer += 2;
 594
 595         pcm = ACCESS_ONCE(s->pcm);
 596         if (pcm)
 597                 s->transfer_samples(s, pcm, buffer, data_blocks);
 598         else
 599                 amdtp_fill_pcm_silence(s, buffer, data_blocks);
 600         if (s->midi_ports)
 601                 amdtp_fill_midi(s, buffer, data_blocks);
 602
 603         s->data_block_counter = (s->data_block_counter + data_blocks) & 0xff;
 604
 605         payload_length = 8 + data_blocks * 4 * s->data_block_quadlets;
 606         if (queue_out_packet(s, payload_length, false) < 0) {
 607                 s->packet_index = -1;
 608                 amdtp_stream_pcm_abort(s);
 609                 return;
 610         }
 611
 612         if (pcm)
 613                 update_pcm_pointers(s, pcm, data_blocks);
 614 }
 615
 616 static void handle_in_packet(struct amdtp_stream *s,
 617                              unsigned int payload_quadlets,
 618                              __be32 *buffer)
 619 {
 620         u32 cip_header[2];
 621         unsigned int data_blocks, data_block_quadlets, data_block_counter;
 622         struct snd_pcm_substream *pcm = NULL;
 623
 624         cip_header[0] = be32_to_cpu(buffer[0]);
 625         cip_header[1] = be32_to_cpu(buffer[1]);
 626
 627         /*
 628          * This module supports 'Two-quadlet CIP header with SYT field'.
 629          * For convenience, also check FMT field is AM824 or not.
 630          */
 631         if (((cip_header[0] & CIP_EOH_MASK) == CIP_EOH) ||
 632             ((cip_header[1] & CIP_EOH_MASK) != CIP_EOH) ||
 633             ((cip_header[1] & CIP_FMT_MASK) != CIP_FMT_AM)) {
 634                 dev_info_ratelimited(&s->unit->device,
 635                                 "Invalid CIP header for AMDTP: %08X:%08X\n",
 636                                 cip_header[0], cip_header[1]);
 637                 goto end;
 638         }
 639
 640         /* Calculate data blocks */
 641         if (payload_quadlets < 3 ||
 642             ((cip_header[1] & CIP_FDF_MASK) ==
 643                                 (AMDTP_FDF_NO_DATA << CIP_FDF_SFC_SHIFT))) {
 644                 data_blocks = 0;
 645         } else {
 646                 data_block_quadlets =
 647                         (cip_header[0] & AMDTP_DBS_MASK) >> AMDTP_DBS_SHIFT;
 648                 /* avoid division by zero */
 649                 if (data_block_quadlets == 0) {
 650                         dev_info_ratelimited(&s->unit->device,
 651                                 "Detect invalid value in dbs field: %08X\n",
 652                                 cip_header[0]);
 653                         goto err;
 654                 }
 655
 656                 data_blocks = (payload_quadlets - 2) / data_block_quadlets;
 657         }
 658
 659         /* Check data block counter continuity */
 660         data_block_counter = cip_header[0] & AMDTP_DBC_MASK;
 661         if (data_block_counter != s->data_block_counter) {
 662                 dev_info(&s->unit->device,
 663                          "Detect discontinuity of CIP: %02X %02X\n",
 664                          s->data_block_counter, data_block_counter);
 665                 goto err;
 666         }
 667
 668         if (data_blocks > 0) {
 669                 buffer += 2;
 670
 671                 pcm = ACCESS_ONCE(s->pcm);
 672                 if (pcm)
 673                         s->transfer_samples(s, pcm, buffer, data_blocks);
 674
 675                 if (s->midi_ports)
 676                         amdtp_pull_midi(s, buffer, data_blocks);
 677         }
 678
 679         s->data_block_counter = (data_block_counter + data_blocks) & 0xff;
 680 end:
 681         if (queue_in_packet(s) < 0)
 682                 goto err;
 683
 684         if (pcm)
 685                 update_pcm_pointers(s, pcm, data_blocks);
 686
 687         return;
 688 err:
 689         s->packet_index = -1;
 690         amdtp_stream_pcm_abort(s);
 691 }
 692
 693 static void out_stream_callback(struct fw_iso_context *context, u32 cycle,
 694                                 size_t header_length, void *header,
 695                                 void *private_data)
 696 {
 697         struct amdtp_stream *s = private_data;
 698         unsigned int i, syt, packets = header_length / 4;
 699
 700         /*
 701          * Compute the cycle of the last queued packet.
 702          * (We need only the four lowest bits for the SYT, so we can ignore
 703          * that bits 0-11 must wrap around at 3072.)
 704          */
 705         cycle += QUEUE_LENGTH - packets;
 706
 707         for (i = 0; i < packets; ++i) {
 708                 syt = calculate_syt(s, ++cycle);
 709                 handle_out_packet(s, syt);
 710         }
 711         fw_iso_context_queue_flush(s->context);
 712 }
 713
 714 static void in_stream_callback(struct fw_iso_context *context, u32 cycle,
 715                                size_t header_length, void *header,
 716                                void *private_data)
 717 {
 718         struct amdtp_stream *s = private_data;
 719         unsigned int p, syt, packets, payload_quadlets;
 720         __be32 *buffer, *headers = header;
 721
 722         /* The number of packets in buffer */
 723         packets = header_length / IN_PACKET_HEADER_SIZE;
 724
 725         for (p = 0; p < packets; p++) {
 726                 if (s->packet_index < 0)
 727                         break;
 728
 729                 buffer = s->buffer.packets[s->packet_index].buffer;
 730
 731                 /* Process sync slave stream */
 732                 if (s->sync_slave && s->sync_slave->callbacked) {
 733                         syt = be32_to_cpu(buffer[1]) & CIP_SYT_MASK;
 734                         handle_out_packet(s->sync_slave, syt);
 735                 }
 736
 737                 /* The number of quadlets in this packet */
 738                 payload_quadlets =
 739                         (be32_to_cpu(headers[p]) >> ISO_DATA_LENGTH_SHIFT) / 4;
 740                 handle_in_packet(s, payload_quadlets, buffer);
 741         }
 742
 743         /* Queueing error or detecting discontinuity */
 744         if (s->packet_index < 0) {
 745                 /* Abort sync slave. */
 746                 if (s->sync_slave) {
 747                         s->sync_slave->packet_index = -1;
 748                         amdtp_stream_pcm_abort(s->sync_slave);
 749                 }
 750                 return;
 751         }
 752
 753         /* when sync to device, flush the packets for slave stream */
 754         if (s->sync_slave && s->sync_slave->callbacked)
 755                 fw_iso_context_queue_flush(s->sync_slave->context);
 756
 757         fw_iso_context_queue_flush(s->context);
 758 }
 759
 760 /* processing is done by master callback */
 761 static void slave_stream_callback(struct fw_iso_context *context, u32 cycle,
 762                                   size_t header_length, void *header,
 763                                   void *private_data)
 764 {
 765         return;
 766 }
 767
 768 /* this is executed one time */
 769 static void amdtp_stream_first_callback(struct fw_iso_context *context,
 770                                         u32 cycle, size_t header_length,
 771                                         void *header, void *private_data)
 772 {
 773         struct amdtp_stream *s = private_data;
 774
 775         /*
 776          * For in-stream, first packet has come.
 777          * For out-stream, prepared to transmit first packet
 778          */
 779         s->callbacked = true;
 780         wake_up(&s->callback_wait);
 781
 782         if (s->direction == AMDTP_IN_STREAM)
 783                 context->callback.sc = in_stream_callback;
 784         else if ((s->flags & CIP_BLOCKING) && (s->flags & CIP_SYNC_TO_DEVICE))
 785                 context->callback.sc = slave_stream_callback;
 786         else
 787                 context->callback.sc = out_stream_callback;
 788
 789         context->callback.sc(context, cycle, header_length, header, s);
 790 }
 791
 792 /**
 793  * amdtp_stream_start - start transferring packets
 794  * @s: the AMDTP stream to start
 795  * @channel: the isochronous channel on the bus
 796  * @speed: firewire speed code
 797  *
 798  * The stream cannot be started until it has been configured with
 799  * amdtp_stream_set_parameters() and it must be started before any PCM or MIDI
 800  * device can be started.
 801  */
 802 int amdtp_stream_start(struct amdtp_stream *s, int channel, int speed)
 803 {
 804         static const struct {
 805                 unsigned int data_block;
 806                 unsigned int syt_offset;
 807         } initial_state[] = {
 808                 [CIP_SFC_32000]  = {  4, 3072 },
 809                 [CIP_SFC_48000]  = {  6, 1024 },
 810                 [CIP_SFC_96000]  = { 12, 1024 },
 811                 [CIP_SFC_192000] = { 24, 1024 },
 812                 [CIP_SFC_44100]  = {  0,   67 },
 813                 [CIP_SFC_88200]  = {  0,   67 },
 814                 [CIP_SFC_176400] = {  0,   67 },
 815         };
 816         unsigned int header_size;
 817         enum dma_data_direction dir;
 818         int type, err;
 819
 820         mutex_lock(&s->mutex);
 821
 822         if (WARN_ON(amdtp_stream_running(s) ||
 823                     (s->data_block_quadlets < 1))) {
 824                 err = -EBADFD;
 825                 goto err_unlock;
 826         }
 827
 828         s->data_block_counter = 0;
 829         s->data_block_state = initial_state[s->sfc].data_block;
 830         s->syt_offset_state = initial_state[s->sfc].syt_offset;
 831         s->last_syt_offset = TICKS_PER_CYCLE;
 832
 833         /* initialize packet buffer */
 834         if (s->direction == AMDTP_IN_STREAM) {
 835                 dir = DMA_FROM_DEVICE;
 836                 type = FW_ISO_CONTEXT_RECEIVE;
 837                 header_size = IN_PACKET_HEADER_SIZE;
 838         } else {
 839                 dir = DMA_TO_DEVICE;
 840                 type = FW_ISO_CONTEXT_TRANSMIT;
 841                 header_size = OUT_PACKET_HEADER_SIZE;
 842         }
 843         err = iso_packets_buffer_init(&s->buffer, s->unit, QUEUE_LENGTH,
 844                                       amdtp_stream_get_max_payload(s), dir);
 845         if (err < 0)
 846                 goto err_unlock;
 847
 848         s->context = fw_iso_context_create(fw_parent_device(s->unit)->card,
 849                                            type, channel, speed, header_size,
 850                                            amdtp_stream_first_callback, s);
 851         if (IS_ERR(s->context)) {
 852                 err = PTR_ERR(s->context);
 853                 if (err == -EBUSY)
 854                         dev_err(&s->unit->device,
 855                                 "no free stream on this controller\n");
 856                 goto err_buffer;
 857         }
 858
 859         amdtp_stream_update(s);
 860
 861         s->packet_index = 0;
 862         do {
 863                 if (s->direction == AMDTP_IN_STREAM)
 864                         err = queue_in_packet(s);
 865                 else
 866                         err = queue_out_packet(s, 0, true);
 867                 if (err < 0)
 868                         goto err_context;
 869         } while (s->packet_index > 0);
 870
 871         /* NOTE: TAG1 matches CIP. This just affects in stream. */
 872         s->callbacked = false;
 873         err = fw_iso_context_start(s->context, -1, 0,
 874                                    FW_ISO_CONTEXT_MATCH_TAG1);
 875         if (err < 0)
 876                 goto err_context;
 877
 878         mutex_unlock(&s->mutex);
 879
 880         return 0;
 881
 882 err_context:
 883         fw_iso_context_destroy(s->context);
 884         s->context = ERR_PTR(-1);
 885 err_buffer:
 886         iso_packets_buffer_destroy(&s->buffer, s->unit);
 887 err_unlock:
 888         mutex_unlock(&s->mutex);
 889
 890         return err;
 891 }
 892 EXPORT_SYMBOL(amdtp_stream_start);
 893
 894 /**
 895  * amdtp_stream_pcm_pointer - get the PCM buffer position
 896  * @s: the AMDTP stream that transports the PCM data
 897  *
 898  * Returns the current buffer position, in frames.
 899  */
 900 unsigned long amdtp_stream_pcm_pointer(struct amdtp_stream *s)
 901 {
 902         /* this optimization is allowed to be racy */
 903         if (s->pointer_flush && amdtp_stream_running(s))
 904                 fw_iso_context_flush_completions(s->context);
 905         else
 906                 s->pointer_flush = true;
 907
 908         return ACCESS_ONCE(s->pcm_buffer_pointer);
 909 }
 910 EXPORT_SYMBOL(amdtp_stream_pcm_pointer);
 911
 912 /**
 913  * amdtp_stream_update - update the stream after a bus reset
 914  * @s: the AMDTP stream
 915  */
 916 void amdtp_stream_update(struct amdtp_stream *s)
 917 {
 918         ACCESS_ONCE(s->source_node_id_field) =
 919                 (fw_parent_device(s->unit)->card->node_id & 0x3f) << 24;
 920 }
 921 EXPORT_SYMBOL(amdtp_stream_update);
 922
 923 /**
 924  * amdtp_stream_stop - stop sending packets
 925  * @s: the AMDTP stream to stop
 926  *
 927  * All PCM and MIDI devices of the stream must be stopped before the stream
 928  * itself can be stopped.
 929  */
 930 void amdtp_stream_stop(struct amdtp_stream *s)
 931 {
 932         mutex_lock(&s->mutex);
 933
 934         if (!amdtp_stream_running(s)) {
 935                 mutex_unlock(&s->mutex);
 936                 return;
 937         }
 938
 939         tasklet_kill(&s->period_tasklet);
 940         fw_iso_context_stop(s->context);
 941         fw_iso_context_destroy(s->context);
 942         s->context = ERR_PTR(-1);
 943         iso_packets_buffer_destroy(&s->buffer, s->unit);
 944
 945         s->callbacked = false;
 946
 947         mutex_unlock(&s->mutex);
 948 }
 949 EXPORT_SYMBOL(amdtp_stream_stop);
 950
 951 /**
 952  * amdtp_stream_pcm_abort - abort the running PCM device
 953  * @s: the AMDTP stream about to be stopped
 954  *
 955  * If the isochronous stream needs to be stopped asynchronously, call this
 956  * function first to stop the PCM device.
 957  */
 958 void amdtp_stream_pcm_abort(struct amdtp_stream *s)
 959 {
 960         struct snd_pcm_substream *pcm;
 961
 962         pcm = ACCESS_ONCE(s->pcm);
 963         if (pcm) {
 964                 snd_pcm_stream_lock_irq(pcm);
 965                 if (snd_pcm_running(pcm))
 966                         snd_pcm_stop(pcm, SNDRV_PCM_STATE_XRUN);
 967                 snd_pcm_stream_unlock_irq(pcm);
 968         }
 969 }
 970 EXPORT_SYMBOL(amdtp_stream_pcm_abort);