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         pcm_chunks = formats->fixed_part_pcm_chunks[mode] +
  80                      formats->differed_part_pcm_chunks[mode];
  81         data_chunks = formats->msg_chunks + pcm_chunks;
  82
  83         /*
  84          * Each data block includes SPH in its head. Data chunks follow with
  85          * 3 byte alignment. Padding follows with zero to conform to quadlet
  86          * alignment.
  87          */
  88         data_block_quadlets = 1 + DIV_ROUND_UP(data_chunks * 3, 4);
  89
  90         err = amdtp_stream_set_parameters(s, rate, data_block_quadlets);
  91         if (err < 0)
  92                 return err;
  93
  94         p->pcm_chunks = pcm_chunks;
  95         p->pcm_byte_offset = formats->pcm_byte_offset;
  96
  97         p->midi_ports = midi_ports;
  98         p->midi_flag_offset = formats->midi_flag_offset;
  99         p->midi_byte_offset = formats->midi_byte_offset;
 100
 101         p->midi_db_count = 0;
 102         p->midi_db_interval = rate / MIDI_BYTES_PER_SECOND;
 103
 104         /* IEEE 1394 bus requires. */
 105         delay = 0x2e00;
 106
 107         /* For no-data or empty packets to adjust PCM sampling frequency. */
 108         delay += 8000 * 3072 * s->syt_interval / rate;
 109
 110         p->next_seconds = 0;
 111         p->next_cycles = delay / 3072;
 112         p->quotient_ticks_per_event = params[s->sfc].quotient_ticks_per_event;
 113         p->remainder_ticks_per_event = params[s->sfc].remainder_ticks_per_event;
 114         p->next_ticks = delay % 3072;
 115         p->next_accumulated = 0;
 116
 117         return 0;
 118 }
 119
 120 static void read_pcm_s32(struct amdtp_stream *s, struct snd_pcm_substream *pcm,
 121                          __be32 *buffer, unsigned int data_blocks,
 122                          unsigned int pcm_frames)
 123 {
 124         struct amdtp_motu *p = s->protocol;
 125         unsigned int channels = p->pcm_chunks;
 126         struct snd_pcm_runtime *runtime = pcm->runtime;
 127         unsigned int pcm_buffer_pointer;
 128         int remaining_frames;
 129         u8 *byte;
 130         u32 *dst;
 131         int i, c;
 132
 133         pcm_buffer_pointer = s->pcm_buffer_pointer + pcm_frames;
 134         pcm_buffer_pointer %= runtime->buffer_size;
 135
 136         dst = (void *)runtime->dma_area +
 137                                 frames_to_bytes(runtime, pcm_buffer_pointer);
 138         remaining_frames = runtime->buffer_size - pcm_buffer_pointer;
 139
 140         for (i = 0; i < data_blocks; ++i) {
 141                 byte = (u8 *)buffer + p->pcm_byte_offset;
 142
 143                 for (c = 0; c < channels; ++c) {
 144                         *dst = (byte[0] << 24) |
 145                                (byte[1] << 16) |
 146                                (byte[2] << 8);
 147                         byte += 3;
 148                         dst++;
 149                 }
 150                 buffer += s->data_block_quadlets;
 151                 if (--remaining_frames == 0)
 152                         dst = (void *)runtime->dma_area;
 153         }
 154 }
 155
 156 static void write_pcm_s32(struct amdtp_stream *s, struct snd_pcm_substream *pcm,
 157                           __be32 *buffer, unsigned int data_blocks,
 158                           unsigned int pcm_frames)
 159 {
 160         struct amdtp_motu *p = s->protocol;
 161         unsigned int channels = p->pcm_chunks;
 162         struct snd_pcm_runtime *runtime = pcm->runtime;
 163         unsigned int pcm_buffer_pointer;
 164         int remaining_frames;
 165         u8 *byte;
 166         const u32 *src;
 167         int i, c;
 168
 169         pcm_buffer_pointer = s->pcm_buffer_pointer + pcm_frames;
 170         pcm_buffer_pointer %= runtime->buffer_size;
 171
 172         src = (void *)runtime->dma_area +
 173                                 frames_to_bytes(runtime, pcm_buffer_pointer);
 174         remaining_frames = runtime->buffer_size - pcm_buffer_pointer;
 175
 176         for (i = 0; i < data_blocks; ++i) {
 177                 byte = (u8 *)buffer + p->pcm_byte_offset;
 178
 179                 for (c = 0; c < channels; ++c) {
 180                         byte[0] = (*src >> 24) & 0xff;
 181                         byte[1] = (*src >> 16) & 0xff;
 182                         byte[2] = (*src >>  8) & 0xff;
 183                         byte += 3;
 184                         src++;
 185                 }
 186
 187                 buffer += s->data_block_quadlets;
 188                 if (--remaining_frames == 0)
 189                         src = (void *)runtime->dma_area;
 190         }
 191 }
 192
 193 static void write_pcm_silence(struct amdtp_stream *s, __be32 *buffer,
 194                               unsigned int data_blocks)
 195 {
 196         struct amdtp_motu *p = s->protocol;
 197         unsigned int channels, i, c;
 198         u8 *byte;
 199
 200         channels = p->pcm_chunks;
 201
 202         for (i = 0; i < data_blocks; ++i) {
 203                 byte = (u8 *)buffer + p->pcm_byte_offset;
 204
 205                 for (c = 0; c < channels; ++c) {
 206                         byte[0] = 0;
 207                         byte[1] = 0;
 208                         byte[2] = 0;
 209                         byte += 3;
 210                 }
 211
 212                 buffer += s->data_block_quadlets;
 213         }
 214 }
 215
 216 int amdtp_motu_add_pcm_hw_constraints(struct amdtp_stream *s,
 217                                       struct snd_pcm_runtime *runtime)
 218 {
 219         int err;
 220
 221         /* TODO: how to set an constraint for exactly 24bit PCM sample? */
 222         err = snd_pcm_hw_constraint_msbits(runtime, 0, 32, 24);
 223         if (err < 0)
 224                 return err;
 225
 226         return amdtp_stream_add_pcm_hw_constraints(s, runtime);
 227 }
 228
 229 void amdtp_motu_midi_trigger(struct amdtp_stream *s, unsigned int port,
 230                              struct snd_rawmidi_substream *midi)
 231 {
 232         struct amdtp_motu *p = s->protocol;
 233
 234         if (port < p->midi_ports)
 235                 WRITE_ONCE(p->midi, midi);
 236 }
 237
 238 static void write_midi_messages(struct amdtp_stream *s, __be32 *buffer,
 239                                 unsigned int data_blocks)
 240 {
 241         struct amdtp_motu *p = s->protocol;
 242         struct snd_rawmidi_substream *midi = READ_ONCE(p->midi);
 243         u8 *b;
 244         int i;
 245
 246         for (i = 0; i < data_blocks; i++) {
 247                 b = (u8 *)buffer;
 248
 249                 if (midi && p->midi_db_count == 0 &&
 250                     snd_rawmidi_transmit(midi, b + p->midi_byte_offset, 1) == 1) {
 251                         b[p->midi_flag_offset] = 0x01;
 252                 } else {
 253                         b[p->midi_byte_offset] = 0x00;
 254                         b[p->midi_flag_offset] = 0x00;
 255                 }
 256
 257                 buffer += s->data_block_quadlets;
 258
 259                 if (--p->midi_db_count < 0)
 260                         p->midi_db_count = p->midi_db_interval;
 261         }
 262 }
 263
 264 static void read_midi_messages(struct amdtp_stream *s, __be32 *buffer,
 265                                unsigned int data_blocks)
 266 {
 267         struct amdtp_motu *p = s->protocol;
 268         struct snd_rawmidi_substream *midi;
 269         u8 *b;
 270         int i;
 271
 272         for (i = 0; i < data_blocks; i++) {
 273                 b = (u8 *)buffer;
 274                 midi = READ_ONCE(p->midi);
 275
 276                 if (midi && (b[p->midi_flag_offset] & 0x01))
 277                         snd_rawmidi_receive(midi, b + p->midi_byte_offset, 1);
 278
 279                 buffer += s->data_block_quadlets;
 280         }
 281 }
 282
 283 /* For tracepoints. */
 284 static void __maybe_unused copy_sph(u32 *frames, __be32 *buffer,
 285                                     unsigned int data_blocks,
 286                                     unsigned int data_block_quadlets)
 287 {
 288         unsigned int i;
 289
 290         for (i = 0; i < data_blocks; ++i) {
 291                 *frames = be32_to_cpu(*buffer);
 292                 buffer += data_block_quadlets;
 293                 frames++;
 294         }
 295 }
 296
 297 /* For tracepoints. */
 298 static void __maybe_unused copy_message(u64 *frames, __be32 *buffer,
 299                                         unsigned int data_blocks,
 300                                         unsigned int data_block_quadlets)
 301 {
 302         unsigned int i;
 303
 304         /* This is just for v2/v3 protocol. */
 305         for (i = 0; i < data_blocks; ++i) {
 306                 *frames = (be32_to_cpu(buffer[1]) << 16) |
 307                           (be32_to_cpu(buffer[2]) >> 16);
 308                 buffer += data_block_quadlets;
 309                 frames++;
 310         }
 311 }
 312
 313 static void probe_tracepoints_events(struct amdtp_stream *s,
 314                                      const struct pkt_desc *descs,
 315                                      unsigned int packets)
 316 {
 317         int i;
 318
 319         for (i = 0; i < packets; ++i) {
 320                 const struct pkt_desc *desc = descs + i;
 321                 __be32 *buf = desc->ctx_payload;
 322                 unsigned int data_blocks = desc->data_blocks;
 323
 324                 trace_data_block_sph(s, data_blocks, buf);
 325                 trace_data_block_message(s, data_blocks, buf);
 326         }
 327 }
 328
 329 static unsigned int process_ir_ctx_payloads(struct amdtp_stream *s,
 330                                             const struct pkt_desc *descs,
 331                                             unsigned int packets,
 332                                             struct snd_pcm_substream *pcm)
 333 {
 334         struct amdtp_motu *p = s->protocol;
 335         unsigned int pcm_frames = 0;
 336         int i;
 337
 338         // For data block processing.
 339         for (i = 0; i < packets; ++i) {
 340                 const struct pkt_desc *desc = descs + i;
 341                 __be32 *buf = desc->ctx_payload;
 342                 unsigned int data_blocks = desc->data_blocks;
 343
 344                 if (pcm) {
 345                         read_pcm_s32(s, pcm, buf, data_blocks, pcm_frames);
 346                         pcm_frames += data_blocks;
 347                 }
 348
 349                 if (p->midi_ports)
 350                         read_midi_messages(s, buf, data_blocks);
 351         }
 352
 353         // For tracepoints.
 354         if (trace_data_block_sph_enabled() ||
 355             trace_data_block_message_enabled())
 356                 probe_tracepoints_events(s, descs, packets);
 357
 358         return pcm_frames;
 359 }
 360
 361 static inline void compute_next_elapse_from_start(struct amdtp_motu *p)
 362 {
 363         p->next_accumulated += p->remainder_ticks_per_event;
 364         if (p->next_accumulated >= 441) {
 365                 p->next_accumulated -= 441;
 366                 p->next_ticks++;
 367         }
 368
 369         p->next_ticks += p->quotient_ticks_per_event;
 370         if (p->next_ticks >= 3072) {
 371                 p->next_ticks -= 3072;
 372                 p->next_cycles++;
 373         }
 374
 375         if (p->next_cycles >= 8000) {
 376                 p->next_cycles -= 8000;
 377                 p->next_seconds++;
 378         }
 379
 380         if (p->next_seconds >= 128)
 381                 p->next_seconds -= 128;
 382 }
 383
 384 static void write_sph(struct amdtp_stream *s, __be32 *buffer,
 385                       unsigned int data_blocks)
 386 {
 387         struct amdtp_motu *p = s->protocol;
 388         unsigned int next_cycles;
 389         unsigned int i;
 390         u32 sph;
 391
 392         for (i = 0; i < data_blocks; i++) {
 393                 next_cycles = (s->start_cycle + p->next_cycles) % 8000;
 394                 sph = ((next_cycles << 12) | p->next_ticks) & 0x01ffffff;
 395                 *buffer = cpu_to_be32(sph);
 396
 397                 compute_next_elapse_from_start(p);
 398
 399                 buffer += s->data_block_quadlets;
 400         }
 401 }
 402
 403 static unsigned int process_it_ctx_payloads(struct amdtp_stream *s,
 404                                             const struct pkt_desc *descs,
 405                                             unsigned int packets,
 406                                             struct snd_pcm_substream *pcm)
 407 {
 408         struct amdtp_motu *p = s->protocol;
 409         unsigned int pcm_frames = 0;
 410         int i;
 411
 412         // For data block processing.
 413         for (i = 0; i < packets; ++i) {
 414                 const struct pkt_desc *desc = descs + i;
 415                 __be32 *buf = desc->ctx_payload;
 416                 unsigned int data_blocks = desc->data_blocks;
 417
 418                 if (pcm) {
 419                         write_pcm_s32(s, pcm, buf, data_blocks, pcm_frames);
 420                         pcm_frames += data_blocks;
 421                 } else {
 422                         write_pcm_silence(s, buf, data_blocks);
 423                 }
 424
 425                 if (p->midi_ports)
 426                         write_midi_messages(s, buf, data_blocks);
 427
 428                 // TODO: how to interact control messages between userspace?
 429
 430                 write_sph(s, buf, data_blocks);
 431         }
 432
 433         // For tracepoints.
 434         if (trace_data_block_sph_enabled() ||
 435             trace_data_block_message_enabled())
 436                 probe_tracepoints_events(s, descs, packets);
 437
 438         return pcm_frames;
 439 }
 440
 441 int amdtp_motu_init(struct amdtp_stream *s, struct fw_unit *unit,
 442                     enum amdtp_stream_direction dir,
 443                     const struct snd_motu_protocol *const protocol)
 444 {
 445         amdtp_stream_process_ctx_payloads_t process_ctx_payloads;
 446         int fmt = CIP_FMT_MOTU;
 447         int flags = CIP_BLOCKING;
 448         int err;
 449
 450         if (dir == AMDTP_IN_STREAM) {
 451                 process_ctx_payloads = process_ir_ctx_payloads;
 452
 453                 /*
 454                  * Units of version 3 transmits packets with invalid CIP header
 455                  * against IEC 61883-1.
 456                  */
 457                 if (protocol == &snd_motu_protocol_v3) {
 458                         flags |= CIP_WRONG_DBS |
 459                                  CIP_SKIP_DBC_ZERO_CHECK |
 460                                  CIP_HEADER_WITHOUT_EOH;
 461                         fmt = CIP_FMT_MOTU_TX_V3;
 462                 }
 463
 464                 if (protocol == &snd_motu_protocol_v2) {
 465                         // 8pre has some quirks.
 466                         flags |= CIP_WRONG_DBS |
 467                                  CIP_SKIP_DBC_ZERO_CHECK;
 468                 }
 469         } else {
 470                 process_ctx_payloads = process_it_ctx_payloads;
 471                 flags |= CIP_DBC_IS_END_EVENT;
 472         }
 473
 474         err = amdtp_stream_init(s, unit, dir, flags, fmt, process_ctx_payloads,
 475                                 sizeof(struct amdtp_motu));
 476         if (err < 0)
 477                 return err;
 478
 479         s->sph = 1;
 480
 481         if (dir == AMDTP_OUT_STREAM) {
 482                 // Use fixed value for FDF field.
 483                 s->ctx_data.rx.fdf = MOTU_FDF_AM824;
 484                 // Not used.
 485                 s->ctx_data.rx.syt_override = 0xffff;
 486         }
 487
 488         return 0;
 489 }