1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Clock domain and sample rate management functions 4 */ 5 6 #include <linux/bitops.h> 7 #include <linux/init.h> 8 #include <linux/string.h> 9 #include <linux/usb.h> 10 #include <linux/usb/audio.h> 11 #include <linux/usb/audio-v2.h> 12 #include <linux/usb/audio-v3.h> 13 14 #include <sound/core.h> 15 #include <sound/info.h> 16 #include <sound/pcm.h> 17 18 #include "usbaudio.h" 19 #include "card.h" 20 #include "helper.h" 21 #include "clock.h" 22 #include "quirks.h" 23 24 static void *find_uac_clock_desc(struct usb_host_interface *iface, int id, 25 bool (*validator)(void *, int), u8 type) 26 { 27 void *cs = NULL; 28 29 while ((cs = snd_usb_find_csint_desc(iface->extra, iface->extralen, 30 cs, type))) { 31 if (validator(cs, id)) 32 return cs; 33 } 34 35 return NULL; 36 } 37 38 static bool validate_clock_source_v2(void *p, int id) 39 { 40 struct uac_clock_source_descriptor *cs = p; 41 return cs->bClockID == id; 42 } 43 44 static bool validate_clock_source_v3(void *p, int id) 45 { 46 struct uac3_clock_source_descriptor *cs = p; 47 return cs->bClockID == id; 48 } 49 50 static bool validate_clock_selector_v2(void *p, int id) 51 { 52 struct uac_clock_selector_descriptor *cs = p; 53 return cs->bClockID == id; 54 } 55 56 static bool validate_clock_selector_v3(void *p, int id) 57 { 58 struct uac3_clock_selector_descriptor *cs = p; 59 return cs->bClockID == id; 60 } 61 62 static bool validate_clock_multiplier_v2(void *p, int id) 63 { 64 struct uac_clock_multiplier_descriptor *cs = p; 65 return cs->bClockID == id; 66 } 67 68 static bool validate_clock_multiplier_v3(void *p, int id) 69 { 70 struct uac3_clock_multiplier_descriptor *cs = p; 71 return cs->bClockID == id; 72 } 73 74 #define DEFINE_FIND_HELPER(name, obj, validator, type) \ 75 static obj *name(struct usb_host_interface *iface, int id) \ 76 { \ 77 return find_uac_clock_desc(iface, id, validator, type); \ 78 } 79 80 DEFINE_FIND_HELPER(snd_usb_find_clock_source, 81 struct uac_clock_source_descriptor, 82 validate_clock_source_v2, UAC2_CLOCK_SOURCE); 83 DEFINE_FIND_HELPER(snd_usb_find_clock_source_v3, 84 struct uac3_clock_source_descriptor, 85 validate_clock_source_v3, UAC3_CLOCK_SOURCE); 86 87 DEFINE_FIND_HELPER(snd_usb_find_clock_selector, 88 struct uac_clock_selector_descriptor, 89 validate_clock_selector_v2, UAC2_CLOCK_SELECTOR); 90 DEFINE_FIND_HELPER(snd_usb_find_clock_selector_v3, 91 struct uac3_clock_selector_descriptor, 92 validate_clock_selector_v3, UAC3_CLOCK_SELECTOR); 93 94 DEFINE_FIND_HELPER(snd_usb_find_clock_multiplier, 95 struct uac_clock_multiplier_descriptor, 96 validate_clock_multiplier_v2, UAC2_CLOCK_MULTIPLIER); 97 DEFINE_FIND_HELPER(snd_usb_find_clock_multiplier_v3, 98 struct uac3_clock_multiplier_descriptor, 99 validate_clock_multiplier_v3, UAC3_CLOCK_MULTIPLIER); 100 101 static int uac_clock_selector_get_val(struct snd_usb_audio *chip, int selector_id) 102 { 103 unsigned char buf; 104 int ret; 105 106 ret = snd_usb_ctl_msg(chip->dev, usb_rcvctrlpipe(chip->dev, 0), 107 UAC2_CS_CUR, 108 USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN, 109 UAC2_CX_CLOCK_SELECTOR << 8, 110 snd_usb_ctrl_intf(chip) | (selector_id << 8), 111 &buf, sizeof(buf)); 112 113 if (ret < 0) 114 return ret; 115 116 return buf; 117 } 118 119 static int uac_clock_selector_set_val(struct snd_usb_audio *chip, int selector_id, 120 unsigned char pin) 121 { 122 int ret; 123 124 ret = snd_usb_ctl_msg(chip->dev, usb_sndctrlpipe(chip->dev, 0), 125 UAC2_CS_CUR, 126 USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_OUT, 127 UAC2_CX_CLOCK_SELECTOR << 8, 128 snd_usb_ctrl_intf(chip) | (selector_id << 8), 129 &pin, sizeof(pin)); 130 if (ret < 0) 131 return ret; 132 133 if (ret != sizeof(pin)) { 134 usb_audio_err(chip, 135 "setting selector (id %d) unexpected length %d\n", 136 selector_id, ret); 137 return -EINVAL; 138 } 139 140 ret = uac_clock_selector_get_val(chip, selector_id); 141 if (ret < 0) 142 return ret; 143 144 if (ret != pin) { 145 usb_audio_err(chip, 146 "setting selector (id %d) to %x failed (current: %d)\n", 147 selector_id, pin, ret); 148 return -EINVAL; 149 } 150 151 return ret; 152 } 153 154 /* 155 * Assume the clock is valid if clock source supports only one single sample 156 * rate, the terminal is connected directly to it (there is no clock selector) 157 * and clock type is internal. This is to deal with some Denon DJ controllers 158 * that always reports that clock is invalid. 159 */ 160 static bool uac_clock_source_is_valid_quirk(struct snd_usb_audio *chip, 161 struct audioformat *fmt, 162 int source_id) 163 { 164 if (fmt->protocol == UAC_VERSION_2) { 165 struct uac_clock_source_descriptor *cs_desc = 166 snd_usb_find_clock_source(chip->ctrl_intf, source_id); 167 168 if (!cs_desc) 169 return false; 170 171 return (fmt->nr_rates == 1 && 172 (fmt->clock & 0xff) == cs_desc->bClockID && 173 (cs_desc->bmAttributes & 0x3) != 174 UAC_CLOCK_SOURCE_TYPE_EXT); 175 } 176 177 return false; 178 } 179 180 static bool uac_clock_source_is_valid(struct snd_usb_audio *chip, 181 struct audioformat *fmt, 182 int source_id) 183 { 184 int err; 185 unsigned char data; 186 struct usb_device *dev = chip->dev; 187 u32 bmControls; 188 189 if (fmt->protocol == UAC_VERSION_3) { 190 struct uac3_clock_source_descriptor *cs_desc = 191 snd_usb_find_clock_source_v3(chip->ctrl_intf, source_id); 192 193 if (!cs_desc) 194 return false; 195 bmControls = le32_to_cpu(cs_desc->bmControls); 196 } else { /* UAC_VERSION_1/2 */ 197 struct uac_clock_source_descriptor *cs_desc = 198 snd_usb_find_clock_source(chip->ctrl_intf, source_id); 199 200 if (!cs_desc) 201 return false; 202 bmControls = cs_desc->bmControls; 203 } 204 205 /* If a clock source can't tell us whether it's valid, we assume it is */ 206 if (!uac_v2v3_control_is_readable(bmControls, 207 UAC2_CS_CONTROL_CLOCK_VALID)) 208 return true; 209 210 err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_CUR, 211 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN, 212 UAC2_CS_CONTROL_CLOCK_VALID << 8, 213 snd_usb_ctrl_intf(chip) | (source_id << 8), 214 &data, sizeof(data)); 215 216 if (err < 0) { 217 dev_warn(&dev->dev, 218 "%s(): cannot get clock validity for id %d\n", 219 __func__, source_id); 220 return false; 221 } 222 223 if (data) 224 return true; 225 else 226 return uac_clock_source_is_valid_quirk(chip, fmt, source_id); 227 } 228 229 static int __uac_clock_find_source(struct snd_usb_audio *chip, 230 struct audioformat *fmt, int entity_id, 231 unsigned long *visited, bool validate) 232 { 233 struct uac_clock_source_descriptor *source; 234 struct uac_clock_selector_descriptor *selector; 235 struct uac_clock_multiplier_descriptor *multiplier; 236 237 entity_id &= 0xff; 238 239 if (test_and_set_bit(entity_id, visited)) { 240 usb_audio_warn(chip, 241 "%s(): recursive clock topology detected, id %d.\n", 242 __func__, entity_id); 243 return -EINVAL; 244 } 245 246 /* first, see if the ID we're looking for is a clock source already */ 247 source = snd_usb_find_clock_source(chip->ctrl_intf, entity_id); 248 if (source) { 249 entity_id = source->bClockID; 250 if (validate && !uac_clock_source_is_valid(chip, fmt, 251 entity_id)) { 252 usb_audio_err(chip, 253 "clock source %d is not valid, cannot use\n", 254 entity_id); 255 return -ENXIO; 256 } 257 return entity_id; 258 } 259 260 selector = snd_usb_find_clock_selector(chip->ctrl_intf, entity_id); 261 if (selector) { 262 int ret, i, cur; 263 264 /* the entity ID we are looking for is a selector. 265 * find out what it currently selects */ 266 ret = uac_clock_selector_get_val(chip, selector->bClockID); 267 if (ret < 0) 268 return ret; 269 270 /* Selector values are one-based */ 271 272 if (ret > selector->bNrInPins || ret < 1) { 273 usb_audio_err(chip, 274 "%s(): selector reported illegal value, id %d, ret %d\n", 275 __func__, selector->bClockID, ret); 276 277 return -EINVAL; 278 } 279 280 cur = ret; 281 ret = __uac_clock_find_source(chip, fmt, 282 selector->baCSourceID[ret - 1], 283 visited, validate); 284 if (!validate || ret > 0 || !chip->autoclock) 285 return ret; 286 287 /* The current clock source is invalid, try others. */ 288 for (i = 1; i <= selector->bNrInPins; i++) { 289 int err; 290 291 if (i == cur) 292 continue; 293 294 ret = __uac_clock_find_source(chip, fmt, 295 selector->baCSourceID[i - 1], 296 visited, true); 297 if (ret < 0) 298 continue; 299 300 err = uac_clock_selector_set_val(chip, entity_id, i); 301 if (err < 0) 302 continue; 303 304 usb_audio_info(chip, 305 "found and selected valid clock source %d\n", 306 ret); 307 return ret; 308 } 309 310 return -ENXIO; 311 } 312 313 /* FIXME: multipliers only act as pass-thru element for now */ 314 multiplier = snd_usb_find_clock_multiplier(chip->ctrl_intf, entity_id); 315 if (multiplier) 316 return __uac_clock_find_source(chip, fmt, 317 multiplier->bCSourceID, 318 visited, validate); 319 320 return -EINVAL; 321 } 322 323 static int __uac3_clock_find_source(struct snd_usb_audio *chip, 324 struct audioformat *fmt, int entity_id, 325 unsigned long *visited, bool validate) 326 { 327 struct uac3_clock_source_descriptor *source; 328 struct uac3_clock_selector_descriptor *selector; 329 struct uac3_clock_multiplier_descriptor *multiplier; 330 331 entity_id &= 0xff; 332 333 if (test_and_set_bit(entity_id, visited)) { 334 usb_audio_warn(chip, 335 "%s(): recursive clock topology detected, id %d.\n", 336 __func__, entity_id); 337 return -EINVAL; 338 } 339 340 /* first, see if the ID we're looking for is a clock source already */ 341 source = snd_usb_find_clock_source_v3(chip->ctrl_intf, entity_id); 342 if (source) { 343 entity_id = source->bClockID; 344 if (validate && !uac_clock_source_is_valid(chip, fmt, 345 entity_id)) { 346 usb_audio_err(chip, 347 "clock source %d is not valid, cannot use\n", 348 entity_id); 349 return -ENXIO; 350 } 351 return entity_id; 352 } 353 354 selector = snd_usb_find_clock_selector_v3(chip->ctrl_intf, entity_id); 355 if (selector) { 356 int ret, i, cur; 357 358 /* the entity ID we are looking for is a selector. 359 * find out what it currently selects */ 360 ret = uac_clock_selector_get_val(chip, selector->bClockID); 361 if (ret < 0) 362 return ret; 363 364 /* Selector values are one-based */ 365 366 if (ret > selector->bNrInPins || ret < 1) { 367 usb_audio_err(chip, 368 "%s(): selector reported illegal value, id %d, ret %d\n", 369 __func__, selector->bClockID, ret); 370 371 return -EINVAL; 372 } 373 374 cur = ret; 375 ret = __uac3_clock_find_source(chip, fmt, 376 selector->baCSourceID[ret - 1], 377 visited, validate); 378 if (!validate || ret > 0 || !chip->autoclock) 379 return ret; 380 381 /* The current clock source is invalid, try others. */ 382 for (i = 1; i <= selector->bNrInPins; i++) { 383 int err; 384 385 if (i == cur) 386 continue; 387 388 ret = __uac3_clock_find_source(chip, fmt, 389 selector->baCSourceID[i - 1], 390 visited, true); 391 if (ret < 0) 392 continue; 393 394 err = uac_clock_selector_set_val(chip, entity_id, i); 395 if (err < 0) 396 continue; 397 398 usb_audio_info(chip, 399 "found and selected valid clock source %d\n", 400 ret); 401 return ret; 402 } 403 404 return -ENXIO; 405 } 406 407 /* FIXME: multipliers only act as pass-thru element for now */ 408 multiplier = snd_usb_find_clock_multiplier_v3(chip->ctrl_intf, 409 entity_id); 410 if (multiplier) 411 return __uac3_clock_find_source(chip, fmt, 412 multiplier->bCSourceID, 413 visited, validate); 414 415 return -EINVAL; 416 } 417 418 /* 419 * For all kinds of sample rate settings and other device queries, 420 * the clock source (end-leaf) must be used. However, clock selectors, 421 * clock multipliers and sample rate converters may be specified as 422 * clock source input to terminal. This functions walks the clock path 423 * to its end and tries to find the source. 424 * 425 * The 'visited' bitfield is used internally to detect recursive loops. 426 * 427 * Returns the clock source UnitID (>=0) on success, or an error. 428 */ 429 int snd_usb_clock_find_source(struct snd_usb_audio *chip, 430 struct audioformat *fmt, bool validate) 431 { 432 DECLARE_BITMAP(visited, 256); 433 memset(visited, 0, sizeof(visited)); 434 435 switch (fmt->protocol) { 436 case UAC_VERSION_2: 437 return __uac_clock_find_source(chip, fmt, fmt->clock, visited, 438 validate); 439 case UAC_VERSION_3: 440 return __uac3_clock_find_source(chip, fmt, fmt->clock, visited, 441 validate); 442 default: 443 return -EINVAL; 444 } 445 } 446 447 static int set_sample_rate_v1(struct snd_usb_audio *chip, int iface, 448 struct usb_host_interface *alts, 449 struct audioformat *fmt, int rate) 450 { 451 struct usb_device *dev = chip->dev; 452 unsigned int ep; 453 unsigned char data[3]; 454 int err, crate; 455 456 if (get_iface_desc(alts)->bNumEndpoints < 1) 457 return -EINVAL; 458 ep = get_endpoint(alts, 0)->bEndpointAddress; 459 460 /* if endpoint doesn't have sampling rate control, bail out */ 461 if (!(fmt->attributes & UAC_EP_CS_ATTR_SAMPLE_RATE)) 462 return 0; 463 464 data[0] = rate; 465 data[1] = rate >> 8; 466 data[2] = rate >> 16; 467 err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC_SET_CUR, 468 USB_TYPE_CLASS | USB_RECIP_ENDPOINT | USB_DIR_OUT, 469 UAC_EP_CS_ATTR_SAMPLE_RATE << 8, ep, 470 data, sizeof(data)); 471 if (err < 0) { 472 dev_err(&dev->dev, "%d:%d: cannot set freq %d to ep %#x\n", 473 iface, fmt->altsetting, rate, ep); 474 return err; 475 } 476 477 /* Don't check the sample rate for devices which we know don't 478 * support reading */ 479 if (snd_usb_get_sample_rate_quirk(chip)) 480 return 0; 481 /* the firmware is likely buggy, don't repeat to fail too many times */ 482 if (chip->sample_rate_read_error > 2) 483 return 0; 484 485 err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC_GET_CUR, 486 USB_TYPE_CLASS | USB_RECIP_ENDPOINT | USB_DIR_IN, 487 UAC_EP_CS_ATTR_SAMPLE_RATE << 8, ep, 488 data, sizeof(data)); 489 if (err < 0) { 490 dev_err(&dev->dev, "%d:%d: cannot get freq at ep %#x\n", 491 iface, fmt->altsetting, ep); 492 chip->sample_rate_read_error++; 493 return 0; /* some devices don't support reading */ 494 } 495 496 crate = data[0] | (data[1] << 8) | (data[2] << 16); 497 if (crate != rate) { 498 dev_warn(&dev->dev, "current rate %d is different from the runtime rate %d\n", crate, rate); 499 // runtime->rate = crate; 500 } 501 502 return 0; 503 } 504 505 static int get_sample_rate_v2v3(struct snd_usb_audio *chip, int iface, 506 int altsetting, int clock) 507 { 508 struct usb_device *dev = chip->dev; 509 __le32 data; 510 int err; 511 512 err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_CUR, 513 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN, 514 UAC2_CS_CONTROL_SAM_FREQ << 8, 515 snd_usb_ctrl_intf(chip) | (clock << 8), 516 &data, sizeof(data)); 517 if (err < 0) { 518 dev_warn(&dev->dev, "%d:%d: cannot get freq (v2/v3): err %d\n", 519 iface, altsetting, err); 520 return 0; 521 } 522 523 return le32_to_cpu(data); 524 } 525 526 static int set_sample_rate_v2v3(struct snd_usb_audio *chip, int iface, 527 struct usb_host_interface *alts, 528 struct audioformat *fmt, int rate) 529 { 530 struct usb_device *dev = chip->dev; 531 __le32 data; 532 int err, cur_rate, prev_rate; 533 int clock; 534 bool writeable; 535 u32 bmControls; 536 537 /* First, try to find a valid clock. This may trigger 538 * automatic clock selection if the current clock is not 539 * valid. 540 */ 541 clock = snd_usb_clock_find_source(chip, fmt, true); 542 if (clock < 0) { 543 /* We did not find a valid clock, but that might be 544 * because the current sample rate does not match an 545 * external clock source. Try again without validation 546 * and we will do another validation after setting the 547 * rate. 548 */ 549 clock = snd_usb_clock_find_source(chip, fmt, false); 550 if (clock < 0) 551 return clock; 552 } 553 554 prev_rate = get_sample_rate_v2v3(chip, iface, fmt->altsetting, clock); 555 if (prev_rate == rate) 556 goto validation; 557 558 if (fmt->protocol == UAC_VERSION_3) { 559 struct uac3_clock_source_descriptor *cs_desc; 560 561 cs_desc = snd_usb_find_clock_source_v3(chip->ctrl_intf, clock); 562 bmControls = le32_to_cpu(cs_desc->bmControls); 563 } else { 564 struct uac_clock_source_descriptor *cs_desc; 565 566 cs_desc = snd_usb_find_clock_source(chip->ctrl_intf, clock); 567 bmControls = cs_desc->bmControls; 568 } 569 570 writeable = uac_v2v3_control_is_writeable(bmControls, 571 UAC2_CS_CONTROL_SAM_FREQ); 572 if (writeable) { 573 data = cpu_to_le32(rate); 574 err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC2_CS_CUR, 575 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT, 576 UAC2_CS_CONTROL_SAM_FREQ << 8, 577 snd_usb_ctrl_intf(chip) | (clock << 8), 578 &data, sizeof(data)); 579 if (err < 0) { 580 usb_audio_err(chip, 581 "%d:%d: cannot set freq %d (v2/v3): err %d\n", 582 iface, fmt->altsetting, rate, err); 583 return err; 584 } 585 586 cur_rate = get_sample_rate_v2v3(chip, iface, 587 fmt->altsetting, clock); 588 } else { 589 cur_rate = prev_rate; 590 } 591 592 if (cur_rate != rate) { 593 if (!writeable) { 594 usb_audio_warn(chip, 595 "%d:%d: freq mismatch (RO clock): req %d, clock runs @%d\n", 596 iface, fmt->altsetting, rate, cur_rate); 597 return -ENXIO; 598 } 599 usb_audio_dbg(chip, 600 "current rate %d is different from the runtime rate %d\n", 601 cur_rate, rate); 602 } 603 604 /* Some devices doesn't respond to sample rate changes while the 605 * interface is active. */ 606 if (rate != prev_rate) { 607 usb_set_interface(dev, iface, 0); 608 snd_usb_set_interface_quirk(dev); 609 usb_set_interface(dev, iface, fmt->altsetting); 610 snd_usb_set_interface_quirk(dev); 611 } 612 613 validation: 614 /* validate clock after rate change */ 615 if (!uac_clock_source_is_valid(chip, fmt, clock)) 616 return -ENXIO; 617 return 0; 618 } 619 620 int snd_usb_init_sample_rate(struct snd_usb_audio *chip, int iface, 621 struct usb_host_interface *alts, 622 struct audioformat *fmt, int rate) 623 { 624 switch (fmt->protocol) { 625 case UAC_VERSION_1: 626 default: 627 return set_sample_rate_v1(chip, iface, alts, fmt, rate); 628 629 case UAC_VERSION_3: 630 if (chip->badd_profile >= UAC3_FUNCTION_SUBCLASS_GENERIC_IO) { 631 if (rate != UAC3_BADD_SAMPLING_RATE) 632 return -ENXIO; 633 else 634 return 0; 635 } 636 /* fall through */ 637 case UAC_VERSION_2: 638 return set_sample_rate_v2v3(chip, iface, alts, fmt, rate); 639 } 640 } 641 642