sound/firewire/motu/amdtp-motu.c

   1 /*
   2  * amdtp-motu.c - a part of driver for MOTU FireWire series
   3  *
   4  * Copyright (c) 2015-2017 Takashi Sakamoto <o-takashi@sakamocchi.jp>
   5  *
   6  * Licensed under the terms of the GNU General Public License, version 2.
   7  */
   8
   9 #include <linux/slab.h>
  10 #include <sound/pcm.h>
  11 #include "motu.h"
  12
  13 #define CREATE_TRACE_POINTS
  14 #include "amdtp-motu-trace.h"
  15
  16 #define CIP_FMT_MOTU            0x02
  17 #define CIP_FMT_MOTU_TX_V3      0x22
  18 #define MOTU_FDF_AM824          0x22
  19
  20 /*
  21  * Nominally 3125 bytes/second, but the MIDI port's clock might be
  22  * 1% too slow, and the bus clock 100 ppm too fast.
  23  */
  24 #define MIDI_BYTES_PER_SECOND   3093
  25
  26 struct amdtp_motu {
  27         /* For timestamp processing.  */
  28         unsigned int quotient_ticks_per_event;
  29         unsigned int remainder_ticks_per_event;
  30         unsigned int next_ticks;
  31         unsigned int next_accumulated;
  32         unsigned int next_cycles;
  33         unsigned int next_seconds;
  34
  35         unsigned int pcm_chunks;
  36         unsigned int pcm_byte_offset;
  37
  38         struct snd_rawmidi_substream *midi;
  39         unsigned int midi_ports;
  40         unsigned int midi_flag_offset;
  41         unsigned int midi_byte_offset;
  42
  43         int midi_db_count;
  44         unsigned int midi_db_interval;
  45 };
  46
  47 int amdtp_motu_set_parameters(struct amdtp_stream *s, unsigned int rate,
  48                               unsigned int midi_ports,
  49                               struct snd_motu_packet_format *formats)
  50 {
  51         static const struct {
  52                 unsigned int quotient_ticks_per_event;
  53                 unsigned int remainder_ticks_per_event;
  54         } params[] = {
  55                 [CIP_SFC_44100]  = { 557, 123 },
  56                 [CIP_SFC_48000]  = { 512,   0 },
  57                 [CIP_SFC_88200]  = { 278, 282 },
  58                 [CIP_SFC_96000]  = { 256,   0 },
  59                 [CIP_SFC_176400] = { 139, 141 },
  60                 [CIP_SFC_192000] = { 128,   0 },
  61         };
  62         struct amdtp_motu *p = s->protocol;
  63         unsigned int pcm_chunks, data_chunks, data_block_quadlets;
  64         unsigned int delay;
  65         unsigned int mode;
  66         int i, err;
  67
  68         if (amdtp_stream_running(s))
  69                 return -EBUSY;
  70
  71         for (i = 0; i < ARRAY_SIZE(snd_motu_clock_rates); ++i) {
  72                 if (snd_motu_clock_rates[i] == rate) {
  73                         mode = i >> 1;
  74                         break;
  75                 }
  76         }
  77         if (i == ARRAY_SIZE(snd_motu_clock_rates))
  78                 return -EINVAL;
  79
  80         pcm_chunks = formats->fixed_part_pcm_chunks[mode] +
  81                      formats->differed_part_pcm_chunks[mode];
  82         data_chunks = formats->msg_chunks + pcm_chunks;
  83
  84         /*
  85          * Each data block includes SPH in its head. Data chunks follow with
  86          * 3 byte alignment. Padding follows with zero to conform to quadlet
  87          * alignment.
  88          */
  89         data_block_quadlets = 1 + DIV_ROUND_UP(data_chunks * 3, 4);
  90
  91         err = amdtp_stream_set_parameters(s, rate, data_block_quadlets);
  92         if (err < 0)
  93                 return err;
  94
  95         p->pcm_chunks = pcm_chunks;
  96         p->pcm_byte_offset = formats->pcm_byte_offset;
  97
  98         p->midi_ports = midi_ports;
  99         p->midi_flag_offset = formats->midi_flag_offset;
 100         p->midi_byte_offset = formats->midi_byte_offset;
 101
 102         p->midi_db_count = 0;
 103         p->midi_db_interval = rate / MIDI_BYTES_PER_SECOND;
 104
 105         /* IEEE 1394 bus requires. */
 106         delay = 0x2e00;
 107
 108         /* For no-data or empty packets to adjust PCM sampling frequency. */
 109         delay += 8000 * 3072 * s->syt_interval / rate;
 110
 111         p->next_seconds = 0;
 112         p->next_cycles = delay / 3072;
 113         p->quotient_ticks_per_event = params[s->sfc].quotient_ticks_per_event;
 114         p->remainder_ticks_per_event = params[s->sfc].remainder_ticks_per_event;
 115         p->next_ticks = delay % 3072;
 116         p->next_accumulated = 0;
 117
 118         return 0;
 119 }
 120
 121 static void read_pcm_s32(struct amdtp_stream *s,
 122                          struct snd_pcm_runtime *runtime,
 123                          __be32 *buffer, unsigned int data_blocks)
 124 {
 125         struct amdtp_motu *p = s->protocol;
 126         unsigned int channels, remaining_frames, i, c;
 127         u8 *byte;
 128         u32 *dst;
 129
 130         channels = p->pcm_chunks;
 131         dst = (void *)runtime->dma_area +
 132                         frames_to_bytes(runtime, s->pcm_buffer_pointer);
 133         remaining_frames = runtime->buffer_size - s->pcm_buffer_pointer;
 134
 135         for (i = 0; i < data_blocks; ++i) {
 136                 byte = (u8 *)buffer + p->pcm_byte_offset;
 137
 138                 for (c = 0; c < channels; ++c) {
 139                         *dst = (byte[0] << 24) | (byte[1] << 16) | byte[2];
 140                         byte += 3;
 141                         dst++;
 142                 }
 143                 buffer += s->data_block_quadlets;
 144                 if (--remaining_frames == 0)
 145                         dst = (void *)runtime->dma_area;
 146         }
 147 }
 148
 149 static void write_pcm_s32(struct amdtp_stream *s,
 150                           struct snd_pcm_runtime *runtime,
 151                           __be32 *buffer, unsigned int data_blocks)
 152 {
 153         struct amdtp_motu *p = s->protocol;
 154         unsigned int channels, remaining_frames, i, c;
 155         u8 *byte;
 156         const u32 *src;
 157
 158         channels = p->pcm_chunks;
 159         src = (void *)runtime->dma_area +
 160                         frames_to_bytes(runtime, s->pcm_buffer_pointer);
 161         remaining_frames = runtime->buffer_size - s->pcm_buffer_pointer;
 162
 163         for (i = 0; i < data_blocks; ++i) {
 164                 byte = (u8 *)buffer + p->pcm_byte_offset;
 165
 166                 for (c = 0; c < channels; ++c) {
 167                         byte[0] = (*src >> 24) & 0xff;
 168                         byte[1] = (*src >> 16) & 0xff;
 169                         byte[2] = (*src >>  8) & 0xff;
 170                         byte += 3;
 171                         src++;
 172                 }
 173
 174                 buffer += s->data_block_quadlets;
 175                 if (--remaining_frames == 0)
 176                         src = (void *)runtime->dma_area;
 177         }
 178 }
 179
 180 static void write_pcm_silence(struct amdtp_stream *s, __be32 *buffer,
 181                               unsigned int data_blocks)
 182 {
 183         struct amdtp_motu *p = s->protocol;
 184         unsigned int channels, i, c;
 185         u8 *byte;
 186
 187         channels = p->pcm_chunks;
 188
 189         for (i = 0; i < data_blocks; ++i) {
 190                 byte = (u8 *)buffer + p->pcm_byte_offset;
 191
 192                 for (c = 0; c < channels; ++c) {
 193                         byte[0] = 0;
 194                         byte[1] = 0;
 195                         byte[2] = 0;
 196                         byte += 3;
 197                 }
 198
 199                 buffer += s->data_block_quadlets;
 200         }
 201 }
 202
 203 int amdtp_motu_add_pcm_hw_constraints(struct amdtp_stream *s,
 204                                       struct snd_pcm_runtime *runtime)
 205 {
 206         int err;
 207
 208         /* TODO: how to set an constraint for exactly 24bit PCM sample? */
 209         err = snd_pcm_hw_constraint_msbits(runtime, 0, 32, 24);
 210         if (err < 0)
 211                 return err;
 212
 213         return amdtp_stream_add_pcm_hw_constraints(s, runtime);
 214 }
 215
 216 void amdtp_motu_midi_trigger(struct amdtp_stream *s, unsigned int port,
 217                              struct snd_rawmidi_substream *midi)
 218 {
 219         struct amdtp_motu *p = s->protocol;
 220
 221         if (port < p->midi_ports)
 222                 WRITE_ONCE(p->midi, midi);
 223 }
 224
 225 static void write_midi_messages(struct amdtp_stream *s, __be32 *buffer,
 226                                 unsigned int data_blocks)
 227 {
 228         struct amdtp_motu *p = s->protocol;
 229         struct snd_rawmidi_substream *midi = READ_ONCE(p->midi);
 230         u8 *b;
 231         int i;
 232
 233         for (i = 0; i < data_blocks; i++) {
 234                 b = (u8 *)buffer;
 235
 236                 if (midi && p->midi_db_count == 0 &&
 237                     snd_rawmidi_transmit(midi, b + p->midi_byte_offset, 1) == 1) {
 238                         b[p->midi_flag_offset] = 0x01;
 239                 } else {
 240                         b[p->midi_byte_offset] = 0x00;
 241                         b[p->midi_flag_offset] = 0x00;
 242                 }
 243
 244                 buffer += s->data_block_quadlets;
 245
 246                 if (--p->midi_db_count < 0)
 247                         p->midi_db_count = p->midi_db_interval;
 248         }
 249 }
 250
 251 static void read_midi_messages(struct amdtp_stream *s, __be32 *buffer,
 252                                unsigned int data_blocks)
 253 {
 254         struct amdtp_motu *p = s->protocol;
 255         struct snd_rawmidi_substream *midi;
 256         u8 *b;
 257         int i;
 258
 259         for (i = 0; i < data_blocks; i++) {
 260                 b = (u8 *)buffer;
 261                 midi = READ_ONCE(p->midi);
 262
 263                 if (midi && (b[p->midi_flag_offset] & 0x01))
 264                         snd_rawmidi_receive(midi, b + p->midi_byte_offset, 1);
 265
 266                 buffer += s->data_block_quadlets;
 267         }
 268 }
 269
 270 /* For tracepoints. */
 271 static void __maybe_unused copy_sph(u32 *frames, __be32 *buffer,
 272                                     unsigned int data_blocks,
 273                                     unsigned int data_block_quadlets)
 274 {
 275         unsigned int i;
 276
 277         for (i = 0; i < data_blocks; ++i) {
 278                 *frames = be32_to_cpu(*buffer);
 279                 buffer += data_block_quadlets;
 280                 frames++;
 281         }
 282 }
 283
 284 /* For tracepoints. */
 285 static void __maybe_unused copy_message(u64 *frames, __be32 *buffer,
 286                                         unsigned int data_blocks,
 287                                         unsigned int data_block_quadlets)
 288 {
 289         unsigned int i;
 290
 291         /* This is just for v2/v3 protocol. */
 292         for (i = 0; i < data_blocks; ++i) {
 293                 *frames = (be32_to_cpu(buffer[1]) << 16) |
 294                           (be32_to_cpu(buffer[2]) >> 16);
 295                 buffer += data_block_quadlets;
 296                 frames++;
 297         }
 298 }
 299
 300 static unsigned int process_tx_data_blocks(struct amdtp_stream *s,
 301                                 __be32 *buffer, unsigned int data_blocks,
 302                                 unsigned int *syt)
 303 {
 304         struct amdtp_motu *p = s->protocol;
 305         struct snd_pcm_substream *pcm;
 306
 307         trace_in_data_block_sph(s, data_blocks, buffer);
 308         trace_in_data_block_message(s, data_blocks, buffer);
 309
 310         if (p->midi_ports)
 311                 read_midi_messages(s, buffer, data_blocks);
 312
 313         pcm = READ_ONCE(s->pcm);
 314         if (data_blocks > 0 && pcm)
 315                 read_pcm_s32(s, pcm->runtime, buffer, data_blocks);
 316
 317         return data_blocks;
 318 }
 319
 320 static inline void compute_next_elapse_from_start(struct amdtp_motu *p)
 321 {
 322         p->next_accumulated += p->remainder_ticks_per_event;
 323         if (p->next_accumulated >= 441) {
 324                 p->next_accumulated -= 441;
 325                 p->next_ticks++;
 326         }
 327
 328         p->next_ticks += p->quotient_ticks_per_event;
 329         if (p->next_ticks >= 3072) {
 330                 p->next_ticks -= 3072;
 331                 p->next_cycles++;
 332         }
 333
 334         if (p->next_cycles >= 8000) {
 335                 p->next_cycles -= 8000;
 336                 p->next_seconds++;
 337         }
 338
 339         if (p->next_seconds >= 128)
 340                 p->next_seconds -= 128;
 341 }
 342
 343 static void write_sph(struct amdtp_stream *s, __be32 *buffer,
 344                       unsigned int data_blocks)
 345 {
 346         struct amdtp_motu *p = s->protocol;
 347         unsigned int next_cycles;
 348         unsigned int i;
 349         u32 sph;
 350
 351         for (i = 0; i < data_blocks; i++) {
 352                 next_cycles = (s->start_cycle + p->next_cycles) % 8000;
 353                 sph = ((next_cycles << 12) | p->next_ticks) & 0x01ffffff;
 354                 *buffer = cpu_to_be32(sph);
 355
 356                 compute_next_elapse_from_start(p);
 357
 358                 buffer += s->data_block_quadlets;
 359         }
 360 }
 361
 362 static unsigned int process_rx_data_blocks(struct amdtp_stream *s,
 363                                 __be32 *buffer, unsigned int data_blocks,
 364                                 unsigned int *syt)
 365 {
 366         struct amdtp_motu *p = (struct amdtp_motu *)s->protocol;
 367         struct snd_pcm_substream *pcm;
 368
 369         /* Not used. */
 370         *syt = 0xffff;
 371
 372         /* TODO: how to interact control messages between userspace? */
 373
 374         if (p->midi_ports)
 375                 write_midi_messages(s, buffer, data_blocks);
 376
 377         pcm = READ_ONCE(s->pcm);
 378         if (pcm)
 379                 write_pcm_s32(s, pcm->runtime, buffer, data_blocks);
 380         else
 381                 write_pcm_silence(s, buffer, data_blocks);
 382
 383         write_sph(s, buffer, data_blocks);
 384
 385         trace_out_data_block_sph(s, data_blocks, buffer);
 386         trace_out_data_block_message(s, data_blocks, buffer);
 387
 388         return data_blocks;
 389 }
 390
 391 int amdtp_motu_init(struct amdtp_stream *s, struct fw_unit *unit,
 392                     enum amdtp_stream_direction dir,
 393                     const struct snd_motu_protocol *const protocol)
 394 {
 395         amdtp_stream_process_data_blocks_t process_data_blocks;
 396         int fmt = CIP_FMT_MOTU;
 397         int flags = CIP_BLOCKING;
 398         int err;
 399
 400         if (dir == AMDTP_IN_STREAM) {
 401                 process_data_blocks = process_tx_data_blocks;
 402
 403                 /*
 404                  * Units of version 3 transmits packets with invalid CIP header
 405                  * against IEC 61883-1.
 406                  */
 407                 if (protocol == &snd_motu_protocol_v3) {
 408                         flags |= CIP_WRONG_DBS |
 409                                  CIP_SKIP_DBC_ZERO_CHECK |
 410                                  CIP_HEADER_WITHOUT_EOH;
 411                         fmt = CIP_FMT_MOTU_TX_V3;
 412                 }
 413         } else {
 414                 process_data_blocks = process_rx_data_blocks;
 415                 flags |= CIP_DBC_IS_END_EVENT;
 416         }
 417
 418         err = amdtp_stream_init(s, unit, dir, flags, fmt, process_data_blocks,
 419                                 sizeof(struct amdtp_motu));
 420         if (err < 0)
 421                 return err;
 422
 423         s->sph = 1;
 424         s->fdf = MOTU_FDF_AM824;
 425
 426         return 0;
 427 }