sound/firewire/motu/amdtp-motu.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * amdtp-motu.c - a part of driver for MOTU FireWire series
   4  *
   5  * Copyright (c) 2015-2017 Takashi Sakamoto <o-takashi@sakamocchi.jp>
   6  */
   7
   8 #include <linux/slab.h>
   9 #include <sound/pcm.h>
  10 #include "motu.h"
  11
  12 #define CREATE_TRACE_POINTS
  13 #include "amdtp-motu-trace.h"
  14
  15 #define CIP_FMT_MOTU            0x02
  16 #define CIP_FMT_MOTU_TX_V3      0x22
  17 #define MOTU_FDF_AM824          0x22
  18
  19 /*
  20  * Nominally 3125 bytes/second, but the MIDI port's clock might be
  21  * 1% too slow, and the bus clock 100 ppm too fast.
  22  */
  23 #define MIDI_BYTES_PER_SECOND   3093
  24
  25 struct amdtp_motu {
  26         /* For timestamp processing.  */
  27         unsigned int quotient_ticks_per_event;
  28         unsigned int remainder_ticks_per_event;
  29         unsigned int next_ticks;
  30         unsigned int next_accumulated;
  31         unsigned int next_cycles;
  32         unsigned int next_seconds;
  33
  34         unsigned int pcm_chunks;
  35         unsigned int pcm_byte_offset;
  36
  37         struct snd_rawmidi_substream *midi;
  38         unsigned int midi_ports;
  39         unsigned int midi_flag_offset;
  40         unsigned int midi_byte_offset;
  41
  42         int midi_db_count;
  43         unsigned int midi_db_interval;
  44 };
  45
  46 int amdtp_motu_set_parameters(struct amdtp_stream *s, unsigned int rate,
  47                               unsigned int midi_ports,
  48                               struct snd_motu_packet_format *formats)
  49 {
  50         static const struct {
  51                 unsigned int quotient_ticks_per_event;
  52                 unsigned int remainder_ticks_per_event;
  53         } params[] = {
  54                 [CIP_SFC_44100]  = { 557, 123 },
  55                 [CIP_SFC_48000]  = { 512,   0 },
  56                 [CIP_SFC_88200]  = { 278, 282 },
  57                 [CIP_SFC_96000]  = { 256,   0 },
  58                 [CIP_SFC_176400] = { 139, 141 },
  59                 [CIP_SFC_192000] = { 128,   0 },
  60         };
  61         struct amdtp_motu *p = s->protocol;
  62         unsigned int pcm_chunks, data_chunks, data_block_quadlets;
  63         unsigned int delay;
  64         unsigned int mode;
  65         int i, err;
  66
  67         if (amdtp_stream_running(s))
  68                 return -EBUSY;
  69
  70         for (i = 0; i < ARRAY_SIZE(snd_motu_clock_rates); ++i) {
  71                 if (snd_motu_clock_rates[i] == rate) {
  72                         mode = i >> 1;
  73                         break;
  74                 }
  75         }
  76         if (i == ARRAY_SIZE(snd_motu_clock_rates))
  77                 return -EINVAL;
  78
  79         // Each data block includes SPH in its head. Data chunks follow with
  80         // 3 byte alignment. Padding follows with zero to conform to quadlet
  81         // alignment.
  82         pcm_chunks = formats->pcm_chunks[mode];
  83         data_chunks = formats->msg_chunks + pcm_chunks;
  84         data_block_quadlets = 1 + DIV_ROUND_UP(data_chunks * 3, 4);
  85
  86         err = amdtp_stream_set_parameters(s, rate, data_block_quadlets);
  87         if (err < 0)
  88                 return err;
  89
  90         p->pcm_chunks = pcm_chunks;
  91         p->pcm_byte_offset = formats->pcm_byte_offset;
  92
  93         p->midi_ports = midi_ports;
  94         p->midi_flag_offset = formats->midi_flag_offset;
  95         p->midi_byte_offset = formats->midi_byte_offset;
  96
  97         p->midi_db_count = 0;
  98         p->midi_db_interval = rate / MIDI_BYTES_PER_SECOND;
  99
 100         /* IEEE 1394 bus requires. */
 101         delay = 0x2e00;
 102
 103         /* For no-data or empty packets to adjust PCM sampling frequency. */
 104         delay += 8000 * 3072 * s->syt_interval / rate;
 105
 106         p->next_seconds = 0;
 107         p->next_cycles = delay / 3072;
 108         p->quotient_ticks_per_event = params[s->sfc].quotient_ticks_per_event;
 109         p->remainder_ticks_per_event = params[s->sfc].remainder_ticks_per_event;
 110         p->next_ticks = delay % 3072;
 111         p->next_accumulated = 0;
 112
 113         return 0;
 114 }
 115
 116 static void read_pcm_s32(struct amdtp_stream *s, struct snd_pcm_substream *pcm,
 117                          __be32 *buffer, unsigned int data_blocks,
 118                          unsigned int pcm_frames)
 119 {
 120         struct amdtp_motu *p = s->protocol;
 121         unsigned int channels = p->pcm_chunks;
 122         struct snd_pcm_runtime *runtime = pcm->runtime;
 123         unsigned int pcm_buffer_pointer;
 124         int remaining_frames;
 125         u8 *byte;
 126         u32 *dst;
 127         int i, c;
 128
 129         pcm_buffer_pointer = s->pcm_buffer_pointer + pcm_frames;
 130         pcm_buffer_pointer %= runtime->buffer_size;
 131
 132         dst = (void *)runtime->dma_area +
 133                                 frames_to_bytes(runtime, pcm_buffer_pointer);
 134         remaining_frames = runtime->buffer_size - pcm_buffer_pointer;
 135
 136         for (i = 0; i < data_blocks; ++i) {
 137                 byte = (u8 *)buffer + p->pcm_byte_offset;
 138
 139                 for (c = 0; c < channels; ++c) {
 140                         *dst = (byte[0] << 24) |
 141                                (byte[1] << 16) |
 142                                (byte[2] << 8);
 143                         byte += 3;
 144                         dst++;
 145                 }
 146                 buffer += s->data_block_quadlets;
 147                 if (--remaining_frames == 0)
 148                         dst = (void *)runtime->dma_area;
 149         }
 150 }
 151
 152 static void write_pcm_s32(struct amdtp_stream *s, struct snd_pcm_substream *pcm,
 153                           __be32 *buffer, unsigned int data_blocks,
 154                           unsigned int pcm_frames)
 155 {
 156         struct amdtp_motu *p = s->protocol;
 157         unsigned int channels = p->pcm_chunks;
 158         struct snd_pcm_runtime *runtime = pcm->runtime;
 159         unsigned int pcm_buffer_pointer;
 160         int remaining_frames;
 161         u8 *byte;
 162         const u32 *src;
 163         int i, c;
 164
 165         pcm_buffer_pointer = s->pcm_buffer_pointer + pcm_frames;
 166         pcm_buffer_pointer %= runtime->buffer_size;
 167
 168         src = (void *)runtime->dma_area +
 169                                 frames_to_bytes(runtime, pcm_buffer_pointer);
 170         remaining_frames = runtime->buffer_size - pcm_buffer_pointer;
 171
 172         for (i = 0; i < data_blocks; ++i) {
 173                 byte = (u8 *)buffer + p->pcm_byte_offset;
 174
 175                 for (c = 0; c < channels; ++c) {
 176                         byte[0] = (*src >> 24) & 0xff;
 177                         byte[1] = (*src >> 16) & 0xff;
 178                         byte[2] = (*src >>  8) & 0xff;
 179                         byte += 3;
 180                         src++;
 181                 }
 182
 183                 buffer += s->data_block_quadlets;
 184                 if (--remaining_frames == 0)
 185                         src = (void *)runtime->dma_area;
 186         }
 187 }
 188
 189 static void write_pcm_silence(struct amdtp_stream *s, __be32 *buffer,
 190                               unsigned int data_blocks)
 191 {
 192         struct amdtp_motu *p = s->protocol;
 193         unsigned int channels, i, c;
 194         u8 *byte;
 195
 196         channels = p->pcm_chunks;
 197
 198         for (i = 0; i < data_blocks; ++i) {
 199                 byte = (u8 *)buffer + p->pcm_byte_offset;
 200
 201                 for (c = 0; c < channels; ++c) {
 202                         byte[0] = 0;
 203                         byte[1] = 0;
 204                         byte[2] = 0;
 205                         byte += 3;
 206                 }
 207
 208                 buffer += s->data_block_quadlets;
 209         }
 210 }
 211
 212 int amdtp_motu_add_pcm_hw_constraints(struct amdtp_stream *s,
 213                                       struct snd_pcm_runtime *runtime)
 214 {
 215         int err;
 216
 217         /* TODO: how to set an constraint for exactly 24bit PCM sample? */
 218         err = snd_pcm_hw_constraint_msbits(runtime, 0, 32, 24);
 219         if (err < 0)
 220                 return err;
 221
 222         return amdtp_stream_add_pcm_hw_constraints(s, runtime);
 223 }
 224
 225 void amdtp_motu_midi_trigger(struct amdtp_stream *s, unsigned int port,
 226                              struct snd_rawmidi_substream *midi)
 227 {
 228         struct amdtp_motu *p = s->protocol;
 229
 230         if (port < p->midi_ports)
 231                 WRITE_ONCE(p->midi, midi);
 232 }
 233
 234 static void write_midi_messages(struct amdtp_stream *s, __be32 *buffer,
 235                                 unsigned int data_blocks)
 236 {
 237         struct amdtp_motu *p = s->protocol;
 238         struct snd_rawmidi_substream *midi = READ_ONCE(p->midi);
 239         u8 *b;
 240         int i;
 241
 242         for (i = 0; i < data_blocks; i++) {
 243                 b = (u8 *)buffer;
 244
 245                 if (midi && p->midi_db_count == 0 &&
 246                     snd_rawmidi_transmit(midi, b + p->midi_byte_offset, 1) == 1) {
 247                         b[p->midi_flag_offset] = 0x01;
 248                 } else {
 249                         b[p->midi_byte_offset] = 0x00;
 250                         b[p->midi_flag_offset] = 0x00;
 251                 }
 252
 253                 buffer += s->data_block_quadlets;
 254
 255                 if (--p->midi_db_count < 0)
 256                         p->midi_db_count = p->midi_db_interval;
 257         }
 258 }
 259
 260 static void read_midi_messages(struct amdtp_stream *s, __be32 *buffer,
 261                                unsigned int data_blocks)
 262 {
 263         struct amdtp_motu *p = s->protocol;
 264         struct snd_rawmidi_substream *midi;
 265         u8 *b;
 266         int i;
 267
 268         for (i = 0; i < data_blocks; i++) {
 269                 b = (u8 *)buffer;
 270                 midi = READ_ONCE(p->midi);
 271
 272                 if (midi && (b[p->midi_flag_offset] & 0x01))
 273                         snd_rawmidi_receive(midi, b + p->midi_byte_offset, 1);
 274
 275                 buffer += s->data_block_quadlets;
 276         }
 277 }
 278
 279 /* For tracepoints. */
 280 static void __maybe_unused copy_sph(u32 *frames, __be32 *buffer,
 281                                     unsigned int data_blocks,
 282                                     unsigned int data_block_quadlets)
 283 {
 284         unsigned int i;
 285
 286         for (i = 0; i < data_blocks; ++i) {
 287                 *frames = be32_to_cpu(*buffer);
 288                 buffer += data_block_quadlets;
 289                 frames++;
 290         }
 291 }
 292
 293 /* For tracepoints. */
 294 static void __maybe_unused copy_message(u64 *frames, __be32 *buffer,
 295                                         unsigned int data_blocks,
 296                                         unsigned int data_block_quadlets)
 297 {
 298         unsigned int i;
 299
 300         /* This is just for v2/v3 protocol. */
 301         for (i = 0; i < data_blocks; ++i) {
 302                 *frames = (be32_to_cpu(buffer[1]) << 16) |
 303                           (be32_to_cpu(buffer[2]) >> 16);
 304                 buffer += data_block_quadlets;
 305                 frames++;
 306         }
 307 }
 308
 309 static void probe_tracepoints_events(struct amdtp_stream *s,
 310                                      const struct pkt_desc *descs,
 311                                      unsigned int packets)
 312 {
 313         int i;
 314
 315         for (i = 0; i < packets; ++i) {
 316                 const struct pkt_desc *desc = descs + i;
 317                 __be32 *buf = desc->ctx_payload;
 318                 unsigned int data_blocks = desc->data_blocks;
 319
 320                 trace_data_block_sph(s, data_blocks, buf);
 321                 trace_data_block_message(s, data_blocks, buf);
 322         }
 323 }
 324
 325 static unsigned int process_ir_ctx_payloads(struct amdtp_stream *s,
 326                                             const struct pkt_desc *descs,
 327                                             unsigned int packets,
 328                                             struct snd_pcm_substream *pcm)
 329 {
 330         struct amdtp_motu *p = s->protocol;
 331         unsigned int pcm_frames = 0;
 332         int i;
 333
 334         // For data block processing.
 335         for (i = 0; i < packets; ++i) {
 336                 const struct pkt_desc *desc = descs + i;
 337                 __be32 *buf = desc->ctx_payload;
 338                 unsigned int data_blocks = desc->data_blocks;
 339
 340                 if (pcm) {
 341                         read_pcm_s32(s, pcm, buf, data_blocks, pcm_frames);
 342                         pcm_frames += data_blocks;
 343                 }
 344
 345                 if (p->midi_ports)
 346                         read_midi_messages(s, buf, data_blocks);
 347         }
 348
 349         // For tracepoints.
 350         if (trace_data_block_sph_enabled() ||
 351             trace_data_block_message_enabled())
 352                 probe_tracepoints_events(s, descs, packets);
 353
 354         return pcm_frames;
 355 }
 356
 357 static inline void compute_next_elapse_from_start(struct amdtp_motu *p)
 358 {
 359         p->next_accumulated += p->remainder_ticks_per_event;
 360         if (p->next_accumulated >= 441) {
 361                 p->next_accumulated -= 441;
 362                 p->next_ticks++;
 363         }
 364
 365         p->next_ticks += p->quotient_ticks_per_event;
 366         if (p->next_ticks >= 3072) {
 367                 p->next_ticks -= 3072;
 368                 p->next_cycles++;
 369         }
 370
 371         if (p->next_cycles >= 8000) {
 372                 p->next_cycles -= 8000;
 373                 p->next_seconds++;
 374         }
 375
 376         if (p->next_seconds >= 128)
 377                 p->next_seconds -= 128;
 378 }
 379
 380 static void write_sph(struct amdtp_stream *s, __be32 *buffer,
 381                       unsigned int data_blocks)
 382 {
 383         struct amdtp_motu *p = s->protocol;
 384         unsigned int next_cycles;
 385         unsigned int i;
 386         u32 sph;
 387
 388         for (i = 0; i < data_blocks; i++) {
 389                 next_cycles = (s->start_cycle + p->next_cycles) % 8000;
 390                 sph = ((next_cycles << 12) | p->next_ticks) & 0x01ffffff;
 391                 *buffer = cpu_to_be32(sph);
 392
 393                 compute_next_elapse_from_start(p);
 394
 395                 buffer += s->data_block_quadlets;
 396         }
 397 }
 398
 399 static unsigned int process_it_ctx_payloads(struct amdtp_stream *s,
 400                                             const struct pkt_desc *descs,
 401                                             unsigned int packets,
 402                                             struct snd_pcm_substream *pcm)
 403 {
 404         struct amdtp_motu *p = s->protocol;
 405         unsigned int pcm_frames = 0;
 406         int i;
 407
 408         // For data block processing.
 409         for (i = 0; i < packets; ++i) {
 410                 const struct pkt_desc *desc = descs + i;
 411                 __be32 *buf = desc->ctx_payload;
 412                 unsigned int data_blocks = desc->data_blocks;
 413
 414                 if (pcm) {
 415                         write_pcm_s32(s, pcm, buf, data_blocks, pcm_frames);
 416                         pcm_frames += data_blocks;
 417                 } else {
 418                         write_pcm_silence(s, buf, data_blocks);
 419                 }
 420
 421                 if (p->midi_ports)
 422                         write_midi_messages(s, buf, data_blocks);
 423
 424                 // TODO: how to interact control messages between userspace?
 425
 426                 write_sph(s, buf, data_blocks);
 427         }
 428
 429         // For tracepoints.
 430         if (trace_data_block_sph_enabled() ||
 431             trace_data_block_message_enabled())
 432                 probe_tracepoints_events(s, descs, packets);
 433
 434         return pcm_frames;
 435 }
 436
 437 int amdtp_motu_init(struct amdtp_stream *s, struct fw_unit *unit,
 438                     enum amdtp_stream_direction dir,
 439                     const struct snd_motu_spec *spec)
 440 {
 441         amdtp_stream_process_ctx_payloads_t process_ctx_payloads;
 442         int fmt = CIP_FMT_MOTU;
 443         int flags = CIP_BLOCKING;
 444         int err;
 445
 446         if (dir == AMDTP_IN_STREAM) {
 447                 process_ctx_payloads = process_ir_ctx_payloads;
 448
 449                 /*
 450                  * Units of version 3 transmits packets with invalid CIP header
 451                  * against IEC 61883-1.
 452                  */
 453                 if (spec->protocol_version == SND_MOTU_PROTOCOL_V3) {
 454                         flags |= CIP_WRONG_DBS |
 455                                  CIP_SKIP_DBC_ZERO_CHECK |
 456                                  CIP_HEADER_WITHOUT_EOH;
 457                         fmt = CIP_FMT_MOTU_TX_V3;
 458                 }
 459
 460                 if (spec == &snd_motu_spec_8pre ||
 461                     spec == &snd_motu_spec_ultralite) {
 462                         // 8pre has some quirks.
 463                         flags |= CIP_WRONG_DBS |
 464                                  CIP_SKIP_DBC_ZERO_CHECK;
 465                 }
 466         } else {
 467                 process_ctx_payloads = process_it_ctx_payloads;
 468                 flags |= CIP_DBC_IS_END_EVENT;
 469         }
 470
 471         err = amdtp_stream_init(s, unit, dir, flags, fmt, process_ctx_payloads,
 472                                 sizeof(struct amdtp_motu));
 473         if (err < 0)
 474                 return err;
 475
 476         s->sph = 1;
 477
 478         if (dir == AMDTP_OUT_STREAM) {
 479                 // Use fixed value for FDF field.
 480                 s->ctx_data.rx.fdf = MOTU_FDF_AM824;
 481                 // Not used.
 482                 s->ctx_data.rx.syt_override = 0xffff;
 483         }
 484
 485         return 0;
 486 }