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 <sound/pcm.h> 15 #include <sound/pcm_params.h> 16 #include "amdtp-stream.h" 17 18 #define TICKS_PER_CYCLE 3072 19 #define CYCLES_PER_SECOND 8000 20 #define TICKS_PER_SECOND (TICKS_PER_CYCLE * CYCLES_PER_SECOND) 21 22 /* Always support Linux tracing subsystem. */ 23 #define CREATE_TRACE_POINTS 24 #include "amdtp-stream-trace.h" 25 26 #define TRANSFER_DELAY_TICKS 0x2e00 /* 479.17 microseconds */ 27 28 /* isochronous header parameters */ 29 #define ISO_DATA_LENGTH_SHIFT 16 30 #define TAG_NO_CIP_HEADER 0 31 #define TAG_CIP 1 32 33 /* common isochronous packet header parameters */ 34 #define CIP_EOH_SHIFT 31 35 #define CIP_EOH (1u << CIP_EOH_SHIFT) 36 #define CIP_EOH_MASK 0x80000000 37 #define CIP_SID_SHIFT 24 38 #define CIP_SID_MASK 0x3f000000 39 #define CIP_DBS_MASK 0x00ff0000 40 #define CIP_DBS_SHIFT 16 41 #define CIP_SPH_MASK 0x00000400 42 #define CIP_SPH_SHIFT 10 43 #define CIP_DBC_MASK 0x000000ff 44 #define CIP_FMT_SHIFT 24 45 #define CIP_FMT_MASK 0x3f000000 46 #define CIP_FDF_MASK 0x00ff0000 47 #define CIP_FDF_SHIFT 16 48 #define CIP_SYT_MASK 0x0000ffff 49 #define CIP_SYT_NO_INFO 0xffff 50 51 /* Audio and Music transfer protocol specific parameters */ 52 #define CIP_FMT_AM 0x10 53 #define AMDTP_FDF_NO_DATA 0xff 54 55 /* TODO: make these configurable */ 56 #define INTERRUPT_INTERVAL 16 57 #define QUEUE_LENGTH 48 58 59 #define IN_PACKET_HEADER_SIZE 4 60 #define OUT_PACKET_HEADER_SIZE 0 61 62 static void pcm_period_tasklet(unsigned long data); 63 64 /** 65 * amdtp_stream_init - initialize an AMDTP stream structure 66 * @s: the AMDTP stream to initialize 67 * @unit: the target of the stream 68 * @dir: the direction of stream 69 * @flags: the packet transmission method to use 70 * @fmt: the value of fmt field in CIP header 71 * @process_data_blocks: callback handler to process data blocks 72 * @protocol_size: the size to allocate newly for protocol 73 */ 74 int amdtp_stream_init(struct amdtp_stream *s, struct fw_unit *unit, 75 enum amdtp_stream_direction dir, enum cip_flags flags, 76 unsigned int fmt, 77 amdtp_stream_process_data_blocks_t process_data_blocks, 78 unsigned int protocol_size) 79 { 80 if (process_data_blocks == NULL) 81 return -EINVAL; 82 83 s->protocol = kzalloc(protocol_size, GFP_KERNEL); 84 if (!s->protocol) 85 return -ENOMEM; 86 87 s->unit = unit; 88 s->direction = dir; 89 s->flags = flags; 90 s->context = ERR_PTR(-1); 91 mutex_init(&s->mutex); 92 tasklet_init(&s->period_tasklet, pcm_period_tasklet, (unsigned long)s); 93 s->packet_index = 0; 94 95 init_waitqueue_head(&s->callback_wait); 96 s->callbacked = false; 97 98 s->fmt = fmt; 99 s->process_data_blocks = process_data_blocks; 100 101 return 0; 102 } 103 EXPORT_SYMBOL(amdtp_stream_init); 104 105 /** 106 * amdtp_stream_destroy - free stream resources 107 * @s: the AMDTP stream to destroy 108 */ 109 void amdtp_stream_destroy(struct amdtp_stream *s) 110 { 111 /* Not initialized. */ 112 if (s->protocol == NULL) 113 return; 114 115 WARN_ON(amdtp_stream_running(s)); 116 kfree(s->protocol); 117 mutex_destroy(&s->mutex); 118 } 119 EXPORT_SYMBOL(amdtp_stream_destroy); 120 121 const unsigned int amdtp_syt_intervals[CIP_SFC_COUNT] = { 122 [CIP_SFC_32000] = 8, 123 [CIP_SFC_44100] = 8, 124 [CIP_SFC_48000] = 8, 125 [CIP_SFC_88200] = 16, 126 [CIP_SFC_96000] = 16, 127 [CIP_SFC_176400] = 32, 128 [CIP_SFC_192000] = 32, 129 }; 130 EXPORT_SYMBOL(amdtp_syt_intervals); 131 132 const unsigned int amdtp_rate_table[CIP_SFC_COUNT] = { 133 [CIP_SFC_32000] = 32000, 134 [CIP_SFC_44100] = 44100, 135 [CIP_SFC_48000] = 48000, 136 [CIP_SFC_88200] = 88200, 137 [CIP_SFC_96000] = 96000, 138 [CIP_SFC_176400] = 176400, 139 [CIP_SFC_192000] = 192000, 140 }; 141 EXPORT_SYMBOL(amdtp_rate_table); 142 143 static int apply_constraint_to_size(struct snd_pcm_hw_params *params, 144 struct snd_pcm_hw_rule *rule) 145 { 146 struct snd_interval *s = hw_param_interval(params, rule->var); 147 const struct snd_interval *r = 148 hw_param_interval_c(params, SNDRV_PCM_HW_PARAM_RATE); 149 struct snd_interval t = {0}; 150 unsigned int step = 0; 151 int i; 152 153 for (i = 0; i < CIP_SFC_COUNT; ++i) { 154 if (snd_interval_test(r, amdtp_rate_table[i])) 155 step = max(step, amdtp_syt_intervals[i]); 156 } 157 158 t.min = roundup(s->min, step); 159 t.max = rounddown(s->max, step); 160 t.integer = 1; 161 162 return snd_interval_refine(s, &t); 163 } 164 165 /** 166 * amdtp_stream_add_pcm_hw_constraints - add hw constraints for PCM substream 167 * @s: the AMDTP stream, which must be initialized. 168 * @runtime: the PCM substream runtime 169 */ 170 int amdtp_stream_add_pcm_hw_constraints(struct amdtp_stream *s, 171 struct snd_pcm_runtime *runtime) 172 { 173 struct snd_pcm_hardware *hw = &runtime->hw; 174 int err; 175 176 hw->info = SNDRV_PCM_INFO_BATCH | 177 SNDRV_PCM_INFO_BLOCK_TRANSFER | 178 SNDRV_PCM_INFO_INTERLEAVED | 179 SNDRV_PCM_INFO_JOINT_DUPLEX | 180 SNDRV_PCM_INFO_MMAP | 181 SNDRV_PCM_INFO_MMAP_VALID; 182 183 /* SNDRV_PCM_INFO_BATCH */ 184 hw->periods_min = 2; 185 hw->periods_max = UINT_MAX; 186 187 /* bytes for a frame */ 188 hw->period_bytes_min = 4 * hw->channels_max; 189 190 /* Just to prevent from allocating much pages. */ 191 hw->period_bytes_max = hw->period_bytes_min * 2048; 192 hw->buffer_bytes_max = hw->period_bytes_max * hw->periods_min; 193 194 /* 195 * Currently firewire-lib processes 16 packets in one software 196 * interrupt callback. This equals to 2msec but actually the 197 * interval of the interrupts has a jitter. 198 * Additionally, even if adding a constraint to fit period size to 199 * 2msec, actual calculated frames per period doesn't equal to 2msec, 200 * depending on sampling rate. 201 * Anyway, the interval to call snd_pcm_period_elapsed() cannot 2msec. 202 * Here let us use 5msec for safe period interrupt. 203 */ 204 err = snd_pcm_hw_constraint_minmax(runtime, 205 SNDRV_PCM_HW_PARAM_PERIOD_TIME, 206 5000, UINT_MAX); 207 if (err < 0) 208 goto end; 209 210 /* Non-Blocking stream has no more constraints */ 211 if (!(s->flags & CIP_BLOCKING)) 212 goto end; 213 214 /* 215 * One AMDTP packet can include some frames. In blocking mode, the 216 * number equals to SYT_INTERVAL. So the number is 8, 16 or 32, 217 * depending on its sampling rate. For accurate period interrupt, it's 218 * preferrable to align period/buffer sizes to current SYT_INTERVAL. 219 */ 220 err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_SIZE, 221 apply_constraint_to_size, NULL, 222 SNDRV_PCM_HW_PARAM_PERIOD_SIZE, 223 SNDRV_PCM_HW_PARAM_RATE, -1); 224 if (err < 0) 225 goto end; 226 err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_SIZE, 227 apply_constraint_to_size, NULL, 228 SNDRV_PCM_HW_PARAM_BUFFER_SIZE, 229 SNDRV_PCM_HW_PARAM_RATE, -1); 230 if (err < 0) 231 goto end; 232 end: 233 return err; 234 } 235 EXPORT_SYMBOL(amdtp_stream_add_pcm_hw_constraints); 236 237 /** 238 * amdtp_stream_set_parameters - set stream parameters 239 * @s: the AMDTP stream to configure 240 * @rate: the sample rate 241 * @data_block_quadlets: the size of a data block in quadlet unit 242 * 243 * The parameters must be set before the stream is started, and must not be 244 * changed while the stream is running. 245 */ 246 int amdtp_stream_set_parameters(struct amdtp_stream *s, unsigned int rate, 247 unsigned int data_block_quadlets) 248 { 249 unsigned int sfc; 250 251 for (sfc = 0; sfc < ARRAY_SIZE(amdtp_rate_table); ++sfc) { 252 if (amdtp_rate_table[sfc] == rate) 253 break; 254 } 255 if (sfc == ARRAY_SIZE(amdtp_rate_table)) 256 return -EINVAL; 257 258 s->sfc = sfc; 259 s->data_block_quadlets = data_block_quadlets; 260 s->syt_interval = amdtp_syt_intervals[sfc]; 261 262 /* default buffering in the device */ 263 s->transfer_delay = TRANSFER_DELAY_TICKS - TICKS_PER_CYCLE; 264 if (s->flags & CIP_BLOCKING) 265 /* additional buffering needed to adjust for no-data packets */ 266 s->transfer_delay += TICKS_PER_SECOND * s->syt_interval / rate; 267 268 return 0; 269 } 270 EXPORT_SYMBOL(amdtp_stream_set_parameters); 271 272 /** 273 * amdtp_stream_get_max_payload - get the stream's packet size 274 * @s: the AMDTP stream 275 * 276 * This function must not be called before the stream has been configured 277 * with amdtp_stream_set_parameters(). 278 */ 279 unsigned int amdtp_stream_get_max_payload(struct amdtp_stream *s) 280 { 281 unsigned int multiplier = 1; 282 unsigned int header_size = 0; 283 284 if (s->flags & CIP_JUMBO_PAYLOAD) 285 multiplier = 5; 286 if (!(s->flags & CIP_NO_HEADER)) 287 header_size = 8; 288 289 return header_size + 290 s->syt_interval * s->data_block_quadlets * 4 * multiplier; 291 } 292 EXPORT_SYMBOL(amdtp_stream_get_max_payload); 293 294 /** 295 * amdtp_stream_pcm_prepare - prepare PCM device for running 296 * @s: the AMDTP stream 297 * 298 * This function should be called from the PCM device's .prepare callback. 299 */ 300 void amdtp_stream_pcm_prepare(struct amdtp_stream *s) 301 { 302 tasklet_kill(&s->period_tasklet); 303 s->pcm_buffer_pointer = 0; 304 s->pcm_period_pointer = 0; 305 } 306 EXPORT_SYMBOL(amdtp_stream_pcm_prepare); 307 308 static unsigned int calculate_data_blocks(struct amdtp_stream *s, 309 unsigned int syt) 310 { 311 unsigned int phase, data_blocks; 312 313 /* Blocking mode. */ 314 if (s->flags & CIP_BLOCKING) { 315 /* This module generate empty packet for 'no data'. */ 316 if (syt == CIP_SYT_NO_INFO) 317 data_blocks = 0; 318 else 319 data_blocks = s->syt_interval; 320 /* Non-blocking mode. */ 321 } else { 322 if (!cip_sfc_is_base_44100(s->sfc)) { 323 /* Sample_rate / 8000 is an integer, and precomputed. */ 324 data_blocks = s->data_block_state; 325 } else { 326 phase = s->data_block_state; 327 328 /* 329 * This calculates the number of data blocks per packet so that 330 * 1) the overall rate is correct and exactly synchronized to 331 * the bus clock, and 332 * 2) packets with a rounded-up number of blocks occur as early 333 * as possible in the sequence (to prevent underruns of the 334 * device's buffer). 335 */ 336 if (s->sfc == CIP_SFC_44100) 337 /* 6 6 5 6 5 6 5 ... */ 338 data_blocks = 5 + ((phase & 1) ^ 339 (phase == 0 || phase >= 40)); 340 else 341 /* 12 11 11 11 11 ... or 23 22 22 22 22 ... */ 342 data_blocks = 11 * (s->sfc >> 1) + (phase == 0); 343 if (++phase >= (80 >> (s->sfc >> 1))) 344 phase = 0; 345 s->data_block_state = phase; 346 } 347 } 348 349 return data_blocks; 350 } 351 352 static unsigned int calculate_syt(struct amdtp_stream *s, 353 unsigned int cycle) 354 { 355 unsigned int syt_offset, phase, index, syt; 356 357 if (s->last_syt_offset < TICKS_PER_CYCLE) { 358 if (!cip_sfc_is_base_44100(s->sfc)) 359 syt_offset = s->last_syt_offset + s->syt_offset_state; 360 else { 361 /* 362 * The time, in ticks, of the n'th SYT_INTERVAL sample is: 363 * n * SYT_INTERVAL * 24576000 / sample_rate 364 * Modulo TICKS_PER_CYCLE, the difference between successive 365 * elements is about 1386.23. Rounding the results of this 366 * formula to the SYT precision results in a sequence of 367 * differences that begins with: 368 * 1386 1386 1387 1386 1386 1386 1387 1386 1386 1386 1387 ... 369 * This code generates _exactly_ the same sequence. 370 */ 371 phase = s->syt_offset_state; 372 index = phase % 13; 373 syt_offset = s->last_syt_offset; 374 syt_offset += 1386 + ((index && !(index & 3)) || 375 phase == 146); 376 if (++phase >= 147) 377 phase = 0; 378 s->syt_offset_state = phase; 379 } 380 } else 381 syt_offset = s->last_syt_offset - TICKS_PER_CYCLE; 382 s->last_syt_offset = syt_offset; 383 384 if (syt_offset < TICKS_PER_CYCLE) { 385 syt_offset += s->transfer_delay; 386 syt = (cycle + syt_offset / TICKS_PER_CYCLE) << 12; 387 syt += syt_offset % TICKS_PER_CYCLE; 388 389 return syt & CIP_SYT_MASK; 390 } else { 391 return CIP_SYT_NO_INFO; 392 } 393 } 394 395 static void update_pcm_pointers(struct amdtp_stream *s, 396 struct snd_pcm_substream *pcm, 397 unsigned int frames) 398 { 399 unsigned int ptr; 400 401 ptr = s->pcm_buffer_pointer + frames; 402 if (ptr >= pcm->runtime->buffer_size) 403 ptr -= pcm->runtime->buffer_size; 404 WRITE_ONCE(s->pcm_buffer_pointer, ptr); 405 406 s->pcm_period_pointer += frames; 407 if (s->pcm_period_pointer >= pcm->runtime->period_size) { 408 s->pcm_period_pointer -= pcm->runtime->period_size; 409 tasklet_hi_schedule(&s->period_tasklet); 410 } 411 } 412 413 static void pcm_period_tasklet(unsigned long data) 414 { 415 struct amdtp_stream *s = (void *)data; 416 struct snd_pcm_substream *pcm = READ_ONCE(s->pcm); 417 418 if (pcm) 419 snd_pcm_period_elapsed(pcm); 420 } 421 422 static int queue_packet(struct amdtp_stream *s, unsigned int header_length, 423 unsigned int payload_length) 424 { 425 struct fw_iso_packet p = {0}; 426 int err = 0; 427 428 if (IS_ERR(s->context)) 429 goto end; 430 431 p.interrupt = IS_ALIGNED(s->packet_index + 1, INTERRUPT_INTERVAL); 432 p.tag = s->tag; 433 p.header_length = header_length; 434 if (payload_length > 0) 435 p.payload_length = payload_length; 436 else 437 p.skip = true; 438 err = fw_iso_context_queue(s->context, &p, &s->buffer.iso_buffer, 439 s->buffer.packets[s->packet_index].offset); 440 if (err < 0) { 441 dev_err(&s->unit->device, "queueing error: %d\n", err); 442 goto end; 443 } 444 445 if (++s->packet_index >= QUEUE_LENGTH) 446 s->packet_index = 0; 447 end: 448 return err; 449 } 450 451 static inline int queue_out_packet(struct amdtp_stream *s, 452 unsigned int payload_length) 453 { 454 return queue_packet(s, OUT_PACKET_HEADER_SIZE, payload_length); 455 } 456 457 static inline int queue_in_packet(struct amdtp_stream *s) 458 { 459 return queue_packet(s, IN_PACKET_HEADER_SIZE, s->max_payload_length); 460 } 461 462 static int handle_out_packet(struct amdtp_stream *s, 463 unsigned int payload_length, unsigned int cycle, 464 unsigned int index) 465 { 466 __be32 *buffer; 467 unsigned int syt; 468 unsigned int data_blocks; 469 unsigned int pcm_frames; 470 struct snd_pcm_substream *pcm; 471 472 buffer = s->buffer.packets[s->packet_index].buffer; 473 syt = calculate_syt(s, cycle); 474 data_blocks = calculate_data_blocks(s, syt); 475 pcm_frames = s->process_data_blocks(s, buffer + 2, data_blocks, &syt); 476 477 if (s->flags & CIP_DBC_IS_END_EVENT) 478 s->data_block_counter = 479 (s->data_block_counter + data_blocks) & 0xff; 480 481 buffer[0] = cpu_to_be32(READ_ONCE(s->source_node_id_field) | 482 (s->data_block_quadlets << CIP_DBS_SHIFT) | 483 ((s->sph << CIP_SPH_SHIFT) & CIP_SPH_MASK) | 484 s->data_block_counter); 485 buffer[1] = cpu_to_be32(CIP_EOH | 486 ((s->fmt << CIP_FMT_SHIFT) & CIP_FMT_MASK) | 487 ((s->fdf << CIP_FDF_SHIFT) & CIP_FDF_MASK) | 488 (syt & CIP_SYT_MASK)); 489 490 if (!(s->flags & CIP_DBC_IS_END_EVENT)) 491 s->data_block_counter = 492 (s->data_block_counter + data_blocks) & 0xff; 493 payload_length = 8 + data_blocks * 4 * s->data_block_quadlets; 494 495 trace_out_packet(s, cycle, buffer, payload_length, index); 496 497 if (queue_out_packet(s, payload_length) < 0) 498 return -EIO; 499 500 pcm = READ_ONCE(s->pcm); 501 if (pcm && pcm_frames > 0) 502 update_pcm_pointers(s, pcm, pcm_frames); 503 504 /* No need to return the number of handled data blocks. */ 505 return 0; 506 } 507 508 static int handle_out_packet_without_header(struct amdtp_stream *s, 509 unsigned int payload_length, unsigned int cycle, 510 unsigned int index) 511 { 512 __be32 *buffer; 513 unsigned int syt; 514 unsigned int data_blocks; 515 unsigned int pcm_frames; 516 struct snd_pcm_substream *pcm; 517 518 buffer = s->buffer.packets[s->packet_index].buffer; 519 syt = calculate_syt(s, cycle); 520 data_blocks = calculate_data_blocks(s, syt); 521 pcm_frames = s->process_data_blocks(s, buffer, data_blocks, &syt); 522 s->data_block_counter = (s->data_block_counter + data_blocks) & 0xff; 523 524 payload_length = data_blocks * 4 * s->data_block_quadlets; 525 526 trace_out_packet_without_header(s, cycle, payload_length, data_blocks, 527 index); 528 529 if (queue_out_packet(s, payload_length) < 0) 530 return -EIO; 531 532 pcm = READ_ONCE(s->pcm); 533 if (pcm && pcm_frames > 0) 534 update_pcm_pointers(s, pcm, pcm_frames); 535 536 /* No need to return the number of handled data blocks. */ 537 return 0; 538 } 539 540 static int handle_in_packet(struct amdtp_stream *s, 541 unsigned int payload_length, unsigned int cycle, 542 unsigned int index) 543 { 544 __be32 *buffer; 545 u32 cip_header[2]; 546 unsigned int sph, fmt, fdf, syt; 547 unsigned int data_block_quadlets, data_block_counter, dbc_interval; 548 unsigned int data_blocks; 549 struct snd_pcm_substream *pcm; 550 unsigned int pcm_frames; 551 bool lost; 552 553 buffer = s->buffer.packets[s->packet_index].buffer; 554 cip_header[0] = be32_to_cpu(buffer[0]); 555 cip_header[1] = be32_to_cpu(buffer[1]); 556 557 trace_in_packet(s, cycle, cip_header, payload_length, index); 558 559 /* 560 * This module supports 'Two-quadlet CIP header with SYT field'. 561 * For convenience, also check FMT field is AM824 or not. 562 */ 563 if ((((cip_header[0] & CIP_EOH_MASK) == CIP_EOH) || 564 ((cip_header[1] & CIP_EOH_MASK) != CIP_EOH)) && 565 (!(s->flags & CIP_HEADER_WITHOUT_EOH))) { 566 dev_info_ratelimited(&s->unit->device, 567 "Invalid CIP header for AMDTP: %08X:%08X\n", 568 cip_header[0], cip_header[1]); 569 data_blocks = 0; 570 pcm_frames = 0; 571 goto end; 572 } 573 574 /* Check valid protocol or not. */ 575 sph = (cip_header[0] & CIP_SPH_MASK) >> CIP_SPH_SHIFT; 576 fmt = (cip_header[1] & CIP_FMT_MASK) >> CIP_FMT_SHIFT; 577 if (sph != s->sph || fmt != s->fmt) { 578 dev_info_ratelimited(&s->unit->device, 579 "Detect unexpected protocol: %08x %08x\n", 580 cip_header[0], cip_header[1]); 581 data_blocks = 0; 582 pcm_frames = 0; 583 goto end; 584 } 585 586 /* Calculate data blocks */ 587 fdf = (cip_header[1] & CIP_FDF_MASK) >> CIP_FDF_SHIFT; 588 if (payload_length < 12 || 589 (fmt == CIP_FMT_AM && fdf == AMDTP_FDF_NO_DATA)) { 590 data_blocks = 0; 591 } else { 592 data_block_quadlets = 593 (cip_header[0] & CIP_DBS_MASK) >> CIP_DBS_SHIFT; 594 /* avoid division by zero */ 595 if (data_block_quadlets == 0) { 596 dev_err(&s->unit->device, 597 "Detect invalid value in dbs field: %08X\n", 598 cip_header[0]); 599 return -EPROTO; 600 } 601 if (s->flags & CIP_WRONG_DBS) 602 data_block_quadlets = s->data_block_quadlets; 603 604 data_blocks = (payload_length / 4 - 2) / 605 data_block_quadlets; 606 } 607 608 /* Check data block counter continuity */ 609 data_block_counter = cip_header[0] & CIP_DBC_MASK; 610 if (data_blocks == 0 && (s->flags & CIP_EMPTY_HAS_WRONG_DBC) && 611 s->data_block_counter != UINT_MAX) 612 data_block_counter = s->data_block_counter; 613 614 if (((s->flags & CIP_SKIP_DBC_ZERO_CHECK) && 615 data_block_counter == s->tx_first_dbc) || 616 s->data_block_counter == UINT_MAX) { 617 lost = false; 618 } else if (!(s->flags & CIP_DBC_IS_END_EVENT)) { 619 lost = data_block_counter != s->data_block_counter; 620 } else { 621 if (data_blocks > 0 && s->tx_dbc_interval > 0) 622 dbc_interval = s->tx_dbc_interval; 623 else 624 dbc_interval = data_blocks; 625 626 lost = data_block_counter != 627 ((s->data_block_counter + dbc_interval) & 0xff); 628 } 629 630 if (lost) { 631 dev_err(&s->unit->device, 632 "Detect discontinuity of CIP: %02X %02X\n", 633 s->data_block_counter, data_block_counter); 634 return -EIO; 635 } 636 637 syt = be32_to_cpu(buffer[1]) & CIP_SYT_MASK; 638 pcm_frames = s->process_data_blocks(s, buffer + 2, data_blocks, &syt); 639 640 if (s->flags & CIP_DBC_IS_END_EVENT) 641 s->data_block_counter = data_block_counter; 642 else 643 s->data_block_counter = 644 (data_block_counter + data_blocks) & 0xff; 645 end: 646 if (queue_in_packet(s) < 0) 647 return -EIO; 648 649 pcm = READ_ONCE(s->pcm); 650 if (pcm && pcm_frames > 0) 651 update_pcm_pointers(s, pcm, pcm_frames); 652 653 return 0; 654 } 655 656 static int handle_in_packet_without_header(struct amdtp_stream *s, 657 unsigned int payload_quadlets, unsigned int cycle, 658 unsigned int index) 659 { 660 __be32 *buffer; 661 unsigned int data_blocks; 662 struct snd_pcm_substream *pcm; 663 unsigned int pcm_frames; 664 665 buffer = s->buffer.packets[s->packet_index].buffer; 666 data_blocks = payload_quadlets / s->data_block_quadlets; 667 668 trace_in_packet_without_header(s, cycle, payload_quadlets, data_blocks, 669 index); 670 671 pcm_frames = s->process_data_blocks(s, buffer, data_blocks, NULL); 672 s->data_block_counter = (s->data_block_counter + data_blocks) & 0xff; 673 674 if (queue_in_packet(s) < 0) 675 return -EIO; 676 677 pcm = READ_ONCE(s->pcm); 678 if (pcm && pcm_frames > 0) 679 update_pcm_pointers(s, pcm, pcm_frames); 680 681 return 0; 682 } 683 684 /* 685 * In CYCLE_TIMER register of IEEE 1394, 7 bits are used to represent second. On 686 * the other hand, in DMA descriptors of 1394 OHCI, 3 bits are used to represent 687 * it. Thus, via Linux firewire subsystem, we can get the 3 bits for second. 688 */ 689 static inline u32 compute_cycle_count(u32 tstamp) 690 { 691 return (((tstamp >> 13) & 0x07) * 8000) + (tstamp & 0x1fff); 692 } 693 694 static inline u32 increment_cycle_count(u32 cycle, unsigned int addend) 695 { 696 cycle += addend; 697 if (cycle >= 8 * CYCLES_PER_SECOND) 698 cycle -= 8 * CYCLES_PER_SECOND; 699 return cycle; 700 } 701 702 static inline u32 decrement_cycle_count(u32 cycle, unsigned int subtrahend) 703 { 704 if (cycle < subtrahend) 705 cycle += 8 * CYCLES_PER_SECOND; 706 return cycle - subtrahend; 707 } 708 709 static void out_stream_callback(struct fw_iso_context *context, u32 tstamp, 710 size_t header_length, void *header, 711 void *private_data) 712 { 713 struct amdtp_stream *s = private_data; 714 unsigned int i, packets = header_length / 4; 715 u32 cycle; 716 717 if (s->packet_index < 0) 718 return; 719 720 cycle = compute_cycle_count(tstamp); 721 722 /* Align to actual cycle count for the last packet. */ 723 cycle = increment_cycle_count(cycle, QUEUE_LENGTH - packets); 724 725 for (i = 0; i < packets; ++i) { 726 cycle = increment_cycle_count(cycle, 1); 727 if (s->handle_packet(s, 0, cycle, i) < 0) { 728 s->packet_index = -1; 729 if (in_interrupt()) 730 amdtp_stream_pcm_abort(s); 731 WRITE_ONCE(s->pcm_buffer_pointer, SNDRV_PCM_POS_XRUN); 732 return; 733 } 734 } 735 736 fw_iso_context_queue_flush(s->context); 737 } 738 739 static void in_stream_callback(struct fw_iso_context *context, u32 tstamp, 740 size_t header_length, void *header, 741 void *private_data) 742 { 743 struct amdtp_stream *s = private_data; 744 unsigned int i, packets; 745 unsigned int payload_length, max_payload_length; 746 __be32 *headers = header; 747 u32 cycle; 748 749 if (s->packet_index < 0) 750 return; 751 752 /* The number of packets in buffer */ 753 packets = header_length / IN_PACKET_HEADER_SIZE; 754 755 cycle = compute_cycle_count(tstamp); 756 757 /* Align to actual cycle count for the last packet. */ 758 cycle = decrement_cycle_count(cycle, packets); 759 760 /* For buffer-over-run prevention. */ 761 max_payload_length = s->max_payload_length; 762 763 for (i = 0; i < packets; i++) { 764 cycle = increment_cycle_count(cycle, 1); 765 766 /* The number of bytes in this packet */ 767 payload_length = 768 (be32_to_cpu(headers[i]) >> ISO_DATA_LENGTH_SHIFT); 769 if (payload_length > max_payload_length) { 770 dev_err(&s->unit->device, 771 "Detect jumbo payload: %04x %04x\n", 772 payload_length, max_payload_length); 773 break; 774 } 775 776 if (s->handle_packet(s, payload_length, cycle, i) < 0) 777 break; 778 } 779 780 /* Queueing error or detecting invalid payload. */ 781 if (i < packets) { 782 s->packet_index = -1; 783 if (in_interrupt()) 784 amdtp_stream_pcm_abort(s); 785 WRITE_ONCE(s->pcm_buffer_pointer, SNDRV_PCM_POS_XRUN); 786 return; 787 } 788 789 fw_iso_context_queue_flush(s->context); 790 } 791 792 /* this is executed one time */ 793 static void amdtp_stream_first_callback(struct fw_iso_context *context, 794 u32 tstamp, size_t header_length, 795 void *header, void *private_data) 796 { 797 struct amdtp_stream *s = private_data; 798 u32 cycle; 799 unsigned int packets; 800 801 /* 802 * For in-stream, first packet has come. 803 * For out-stream, prepared to transmit first packet 804 */ 805 s->callbacked = true; 806 wake_up(&s->callback_wait); 807 808 cycle = compute_cycle_count(tstamp); 809 810 if (s->direction == AMDTP_IN_STREAM) { 811 packets = header_length / IN_PACKET_HEADER_SIZE; 812 cycle = decrement_cycle_count(cycle, packets); 813 context->callback.sc = in_stream_callback; 814 if (s->flags & CIP_NO_HEADER) 815 s->handle_packet = handle_in_packet_without_header; 816 else 817 s->handle_packet = handle_in_packet; 818 } else { 819 packets = header_length / 4; 820 cycle = increment_cycle_count(cycle, QUEUE_LENGTH - packets); 821 context->callback.sc = out_stream_callback; 822 if (s->flags & CIP_NO_HEADER) 823 s->handle_packet = handle_out_packet_without_header; 824 else 825 s->handle_packet = handle_out_packet; 826 } 827 828 s->start_cycle = cycle; 829 830 context->callback.sc(context, tstamp, header_length, header, s); 831 } 832 833 /** 834 * amdtp_stream_start - start transferring packets 835 * @s: the AMDTP stream to start 836 * @channel: the isochronous channel on the bus 837 * @speed: firewire speed code 838 * 839 * The stream cannot be started until it has been configured with 840 * amdtp_stream_set_parameters() and it must be started before any PCM or MIDI 841 * device can be started. 842 */ 843 int amdtp_stream_start(struct amdtp_stream *s, int channel, int speed) 844 { 845 static const struct { 846 unsigned int data_block; 847 unsigned int syt_offset; 848 } initial_state[] = { 849 [CIP_SFC_32000] = { 4, 3072 }, 850 [CIP_SFC_48000] = { 6, 1024 }, 851 [CIP_SFC_96000] = { 12, 1024 }, 852 [CIP_SFC_192000] = { 24, 1024 }, 853 [CIP_SFC_44100] = { 0, 67 }, 854 [CIP_SFC_88200] = { 0, 67 }, 855 [CIP_SFC_176400] = { 0, 67 }, 856 }; 857 unsigned int header_size; 858 enum dma_data_direction dir; 859 int type, tag, err; 860 861 mutex_lock(&s->mutex); 862 863 if (WARN_ON(amdtp_stream_running(s) || 864 (s->data_block_quadlets < 1))) { 865 err = -EBADFD; 866 goto err_unlock; 867 } 868 869 if (s->direction == AMDTP_IN_STREAM) 870 s->data_block_counter = UINT_MAX; 871 else 872 s->data_block_counter = 0; 873 s->data_block_state = initial_state[s->sfc].data_block; 874 s->syt_offset_state = initial_state[s->sfc].syt_offset; 875 s->last_syt_offset = TICKS_PER_CYCLE; 876 877 /* initialize packet buffer */ 878 if (s->direction == AMDTP_IN_STREAM) { 879 dir = DMA_FROM_DEVICE; 880 type = FW_ISO_CONTEXT_RECEIVE; 881 header_size = IN_PACKET_HEADER_SIZE; 882 } else { 883 dir = DMA_TO_DEVICE; 884 type = FW_ISO_CONTEXT_TRANSMIT; 885 header_size = OUT_PACKET_HEADER_SIZE; 886 } 887 err = iso_packets_buffer_init(&s->buffer, s->unit, QUEUE_LENGTH, 888 amdtp_stream_get_max_payload(s), dir); 889 if (err < 0) 890 goto err_unlock; 891 892 s->context = fw_iso_context_create(fw_parent_device(s->unit)->card, 893 type, channel, speed, header_size, 894 amdtp_stream_first_callback, s); 895 if (IS_ERR(s->context)) { 896 err = PTR_ERR(s->context); 897 if (err == -EBUSY) 898 dev_err(&s->unit->device, 899 "no free stream on this controller\n"); 900 goto err_buffer; 901 } 902 903 amdtp_stream_update(s); 904 905 if (s->direction == AMDTP_IN_STREAM) 906 s->max_payload_length = amdtp_stream_get_max_payload(s); 907 908 if (s->flags & CIP_NO_HEADER) 909 s->tag = TAG_NO_CIP_HEADER; 910 else 911 s->tag = TAG_CIP; 912 913 s->packet_index = 0; 914 do { 915 if (s->direction == AMDTP_IN_STREAM) 916 err = queue_in_packet(s); 917 else 918 err = queue_out_packet(s, 0); 919 if (err < 0) 920 goto err_context; 921 } while (s->packet_index > 0); 922 923 /* NOTE: TAG1 matches CIP. This just affects in stream. */ 924 tag = FW_ISO_CONTEXT_MATCH_TAG1; 925 if ((s->flags & CIP_EMPTY_WITH_TAG0) || (s->flags & CIP_NO_HEADER)) 926 tag |= FW_ISO_CONTEXT_MATCH_TAG0; 927 928 s->callbacked = false; 929 err = fw_iso_context_start(s->context, -1, 0, tag); 930 if (err < 0) 931 goto err_context; 932 933 mutex_unlock(&s->mutex); 934 935 return 0; 936 937 err_context: 938 fw_iso_context_destroy(s->context); 939 s->context = ERR_PTR(-1); 940 err_buffer: 941 iso_packets_buffer_destroy(&s->buffer, s->unit); 942 err_unlock: 943 mutex_unlock(&s->mutex); 944 945 return err; 946 } 947 EXPORT_SYMBOL(amdtp_stream_start); 948 949 /** 950 * amdtp_stream_pcm_pointer - get the PCM buffer position 951 * @s: the AMDTP stream that transports the PCM data 952 * 953 * Returns the current buffer position, in frames. 954 */ 955 unsigned long amdtp_stream_pcm_pointer(struct amdtp_stream *s) 956 { 957 /* 958 * This function is called in software IRQ context of period_tasklet or 959 * process context. 960 * 961 * When the software IRQ context was scheduled by software IRQ context 962 * of IR/IT contexts, queued packets were already handled. Therefore, 963 * no need to flush the queue in buffer anymore. 964 * 965 * When the process context reach here, some packets will be already 966 * queued in the buffer. These packets should be handled immediately 967 * to keep better granularity of PCM pointer. 968 * 969 * Later, the process context will sometimes schedules software IRQ 970 * context of the period_tasklet. Then, no need to flush the queue by 971 * the same reason as described for IR/IT contexts. 972 */ 973 if (!in_interrupt() && amdtp_stream_running(s)) 974 fw_iso_context_flush_completions(s->context); 975 976 return READ_ONCE(s->pcm_buffer_pointer); 977 } 978 EXPORT_SYMBOL(amdtp_stream_pcm_pointer); 979 980 /** 981 * amdtp_stream_pcm_ack - acknowledge queued PCM frames 982 * @s: the AMDTP stream that transfers the PCM frames 983 * 984 * Returns zero always. 985 */ 986 int amdtp_stream_pcm_ack(struct amdtp_stream *s) 987 { 988 /* 989 * Process isochronous packets for recent isochronous cycle to handle 990 * queued PCM frames. 991 */ 992 if (amdtp_stream_running(s)) 993 fw_iso_context_flush_completions(s->context); 994 995 return 0; 996 } 997 EXPORT_SYMBOL(amdtp_stream_pcm_ack); 998 999 /** 1000 * amdtp_stream_update - update the stream after a bus reset 1001 * @s: the AMDTP stream 1002 */ 1003 void amdtp_stream_update(struct amdtp_stream *s) 1004 { 1005 /* Precomputing. */ 1006 WRITE_ONCE(s->source_node_id_field, 1007 (fw_parent_device(s->unit)->card->node_id << CIP_SID_SHIFT) & CIP_SID_MASK); 1008 } 1009 EXPORT_SYMBOL(amdtp_stream_update); 1010 1011 /** 1012 * amdtp_stream_stop - stop sending packets 1013 * @s: the AMDTP stream to stop 1014 * 1015 * All PCM and MIDI devices of the stream must be stopped before the stream 1016 * itself can be stopped. 1017 */ 1018 void amdtp_stream_stop(struct amdtp_stream *s) 1019 { 1020 mutex_lock(&s->mutex); 1021 1022 if (!amdtp_stream_running(s)) { 1023 mutex_unlock(&s->mutex); 1024 return; 1025 } 1026 1027 tasklet_kill(&s->period_tasklet); 1028 fw_iso_context_stop(s->context); 1029 fw_iso_context_destroy(s->context); 1030 s->context = ERR_PTR(-1); 1031 iso_packets_buffer_destroy(&s->buffer, s->unit); 1032 1033 s->callbacked = false; 1034 1035 mutex_unlock(&s->mutex); 1036 } 1037 EXPORT_SYMBOL(amdtp_stream_stop); 1038 1039 /** 1040 * amdtp_stream_pcm_abort - abort the running PCM device 1041 * @s: the AMDTP stream about to be stopped 1042 * 1043 * If the isochronous stream needs to be stopped asynchronously, call this 1044 * function first to stop the PCM device. 1045 */ 1046 void amdtp_stream_pcm_abort(struct amdtp_stream *s) 1047 { 1048 struct snd_pcm_substream *pcm; 1049 1050 pcm = READ_ONCE(s->pcm); 1051 if (pcm) 1052 snd_pcm_stop_xrun(pcm); 1053 } 1054 EXPORT_SYMBOL(amdtp_stream_pcm_abort); 1055