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 static bool uac_clock_source_is_valid(struct snd_usb_audio *chip, 155 int protocol, 156 int source_id) 157 { 158 int err; 159 unsigned char data; 160 struct usb_device *dev = chip->dev; 161 u32 bmControls; 162 163 if (protocol == UAC_VERSION_3) { 164 struct uac3_clock_source_descriptor *cs_desc = 165 snd_usb_find_clock_source_v3(chip->ctrl_intf, source_id); 166 167 if (!cs_desc) 168 return 0; 169 bmControls = le32_to_cpu(cs_desc->bmControls); 170 } else { /* UAC_VERSION_1/2 */ 171 struct uac_clock_source_descriptor *cs_desc = 172 snd_usb_find_clock_source(chip->ctrl_intf, source_id); 173 174 if (!cs_desc) 175 return 0; 176 bmControls = cs_desc->bmControls; 177 } 178 179 /* If a clock source can't tell us whether it's valid, we assume it is */ 180 if (!uac_v2v3_control_is_readable(bmControls, 181 UAC2_CS_CONTROL_CLOCK_VALID)) 182 return 1; 183 184 err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_CUR, 185 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN, 186 UAC2_CS_CONTROL_CLOCK_VALID << 8, 187 snd_usb_ctrl_intf(chip) | (source_id << 8), 188 &data, sizeof(data)); 189 190 if (err < 0) { 191 dev_warn(&dev->dev, 192 "%s(): cannot get clock validity for id %d\n", 193 __func__, source_id); 194 return 0; 195 } 196 197 return !!data; 198 } 199 200 static int __uac_clock_find_source(struct snd_usb_audio *chip, int entity_id, 201 unsigned long *visited, bool validate) 202 { 203 struct uac_clock_source_descriptor *source; 204 struct uac_clock_selector_descriptor *selector; 205 struct uac_clock_multiplier_descriptor *multiplier; 206 207 entity_id &= 0xff; 208 209 if (test_and_set_bit(entity_id, visited)) { 210 usb_audio_warn(chip, 211 "%s(): recursive clock topology detected, id %d.\n", 212 __func__, entity_id); 213 return -EINVAL; 214 } 215 216 /* first, see if the ID we're looking for is a clock source already */ 217 source = snd_usb_find_clock_source(chip->ctrl_intf, entity_id); 218 if (source) { 219 entity_id = source->bClockID; 220 if (validate && !uac_clock_source_is_valid(chip, UAC_VERSION_2, 221 entity_id)) { 222 usb_audio_err(chip, 223 "clock source %d is not valid, cannot use\n", 224 entity_id); 225 return -ENXIO; 226 } 227 return entity_id; 228 } 229 230 selector = snd_usb_find_clock_selector(chip->ctrl_intf, entity_id); 231 if (selector) { 232 int ret, i, cur; 233 234 /* the entity ID we are looking for is a selector. 235 * find out what it currently selects */ 236 ret = uac_clock_selector_get_val(chip, selector->bClockID); 237 if (ret < 0) 238 return ret; 239 240 /* Selector values are one-based */ 241 242 if (ret > selector->bNrInPins || ret < 1) { 243 usb_audio_err(chip, 244 "%s(): selector reported illegal value, id %d, ret %d\n", 245 __func__, selector->bClockID, ret); 246 247 return -EINVAL; 248 } 249 250 cur = ret; 251 ret = __uac_clock_find_source(chip, selector->baCSourceID[ret - 1], 252 visited, validate); 253 if (!validate || ret > 0 || !chip->autoclock) 254 return ret; 255 256 /* The current clock source is invalid, try others. */ 257 for (i = 1; i <= selector->bNrInPins; i++) { 258 int err; 259 260 if (i == cur) 261 continue; 262 263 ret = __uac_clock_find_source(chip, selector->baCSourceID[i - 1], 264 visited, true); 265 if (ret < 0) 266 continue; 267 268 err = uac_clock_selector_set_val(chip, entity_id, i); 269 if (err < 0) 270 continue; 271 272 usb_audio_info(chip, 273 "found and selected valid clock source %d\n", 274 ret); 275 return ret; 276 } 277 278 return -ENXIO; 279 } 280 281 /* FIXME: multipliers only act as pass-thru element for now */ 282 multiplier = snd_usb_find_clock_multiplier(chip->ctrl_intf, entity_id); 283 if (multiplier) 284 return __uac_clock_find_source(chip, multiplier->bCSourceID, 285 visited, validate); 286 287 return -EINVAL; 288 } 289 290 static int __uac3_clock_find_source(struct snd_usb_audio *chip, int entity_id, 291 unsigned long *visited, bool validate) 292 { 293 struct uac3_clock_source_descriptor *source; 294 struct uac3_clock_selector_descriptor *selector; 295 struct uac3_clock_multiplier_descriptor *multiplier; 296 297 entity_id &= 0xff; 298 299 if (test_and_set_bit(entity_id, visited)) { 300 usb_audio_warn(chip, 301 "%s(): recursive clock topology detected, id %d.\n", 302 __func__, entity_id); 303 return -EINVAL; 304 } 305 306 /* first, see if the ID we're looking for is a clock source already */ 307 source = snd_usb_find_clock_source_v3(chip->ctrl_intf, entity_id); 308 if (source) { 309 entity_id = source->bClockID; 310 if (validate && !uac_clock_source_is_valid(chip, UAC_VERSION_3, 311 entity_id)) { 312 usb_audio_err(chip, 313 "clock source %d is not valid, cannot use\n", 314 entity_id); 315 return -ENXIO; 316 } 317 return entity_id; 318 } 319 320 selector = snd_usb_find_clock_selector_v3(chip->ctrl_intf, entity_id); 321 if (selector) { 322 int ret, i, cur; 323 324 /* the entity ID we are looking for is a selector. 325 * find out what it currently selects */ 326 ret = uac_clock_selector_get_val(chip, selector->bClockID); 327 if (ret < 0) 328 return ret; 329 330 /* Selector values are one-based */ 331 332 if (ret > selector->bNrInPins || ret < 1) { 333 usb_audio_err(chip, 334 "%s(): selector reported illegal value, id %d, ret %d\n", 335 __func__, selector->bClockID, ret); 336 337 return -EINVAL; 338 } 339 340 cur = ret; 341 ret = __uac3_clock_find_source(chip, selector->baCSourceID[ret - 1], 342 visited, validate); 343 if (!validate || ret > 0 || !chip->autoclock) 344 return ret; 345 346 /* The current clock source is invalid, try others. */ 347 for (i = 1; i <= selector->bNrInPins; i++) { 348 int err; 349 350 if (i == cur) 351 continue; 352 353 ret = __uac3_clock_find_source(chip, selector->baCSourceID[i - 1], 354 visited, true); 355 if (ret < 0) 356 continue; 357 358 err = uac_clock_selector_set_val(chip, entity_id, i); 359 if (err < 0) 360 continue; 361 362 usb_audio_info(chip, 363 "found and selected valid clock source %d\n", 364 ret); 365 return ret; 366 } 367 368 return -ENXIO; 369 } 370 371 /* FIXME: multipliers only act as pass-thru element for now */ 372 multiplier = snd_usb_find_clock_multiplier_v3(chip->ctrl_intf, 373 entity_id); 374 if (multiplier) 375 return __uac3_clock_find_source(chip, multiplier->bCSourceID, 376 visited, validate); 377 378 return -EINVAL; 379 } 380 381 /* 382 * For all kinds of sample rate settings and other device queries, 383 * the clock source (end-leaf) must be used. However, clock selectors, 384 * clock multipliers and sample rate converters may be specified as 385 * clock source input to terminal. This functions walks the clock path 386 * to its end and tries to find the source. 387 * 388 * The 'visited' bitfield is used internally to detect recursive loops. 389 * 390 * Returns the clock source UnitID (>=0) on success, or an error. 391 */ 392 int snd_usb_clock_find_source(struct snd_usb_audio *chip, int protocol, 393 int entity_id, bool validate) 394 { 395 DECLARE_BITMAP(visited, 256); 396 memset(visited, 0, sizeof(visited)); 397 398 switch (protocol) { 399 case UAC_VERSION_2: 400 return __uac_clock_find_source(chip, entity_id, visited, 401 validate); 402 case UAC_VERSION_3: 403 return __uac3_clock_find_source(chip, entity_id, visited, 404 validate); 405 default: 406 return -EINVAL; 407 } 408 } 409 410 static int set_sample_rate_v1(struct snd_usb_audio *chip, int iface, 411 struct usb_host_interface *alts, 412 struct audioformat *fmt, int rate) 413 { 414 struct usb_device *dev = chip->dev; 415 unsigned int ep; 416 unsigned char data[3]; 417 int err, crate; 418 419 if (get_iface_desc(alts)->bNumEndpoints < 1) 420 return -EINVAL; 421 ep = get_endpoint(alts, 0)->bEndpointAddress; 422 423 /* if endpoint doesn't have sampling rate control, bail out */ 424 if (!(fmt->attributes & UAC_EP_CS_ATTR_SAMPLE_RATE)) 425 return 0; 426 427 data[0] = rate; 428 data[1] = rate >> 8; 429 data[2] = rate >> 16; 430 err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC_SET_CUR, 431 USB_TYPE_CLASS | USB_RECIP_ENDPOINT | USB_DIR_OUT, 432 UAC_EP_CS_ATTR_SAMPLE_RATE << 8, ep, 433 data, sizeof(data)); 434 if (err < 0) { 435 dev_err(&dev->dev, "%d:%d: cannot set freq %d to ep %#x\n", 436 iface, fmt->altsetting, rate, ep); 437 return err; 438 } 439 440 /* Don't check the sample rate for devices which we know don't 441 * support reading */ 442 if (snd_usb_get_sample_rate_quirk(chip)) 443 return 0; 444 /* the firmware is likely buggy, don't repeat to fail too many times */ 445 if (chip->sample_rate_read_error > 2) 446 return 0; 447 448 err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC_GET_CUR, 449 USB_TYPE_CLASS | USB_RECIP_ENDPOINT | USB_DIR_IN, 450 UAC_EP_CS_ATTR_SAMPLE_RATE << 8, ep, 451 data, sizeof(data)); 452 if (err < 0) { 453 dev_err(&dev->dev, "%d:%d: cannot get freq at ep %#x\n", 454 iface, fmt->altsetting, ep); 455 chip->sample_rate_read_error++; 456 return 0; /* some devices don't support reading */ 457 } 458 459 crate = data[0] | (data[1] << 8) | (data[2] << 16); 460 if (crate != rate) { 461 dev_warn(&dev->dev, "current rate %d is different from the runtime rate %d\n", crate, rate); 462 // runtime->rate = crate; 463 } 464 465 return 0; 466 } 467 468 static int get_sample_rate_v2v3(struct snd_usb_audio *chip, int iface, 469 int altsetting, int clock) 470 { 471 struct usb_device *dev = chip->dev; 472 __le32 data; 473 int err; 474 475 err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_CUR, 476 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN, 477 UAC2_CS_CONTROL_SAM_FREQ << 8, 478 snd_usb_ctrl_intf(chip) | (clock << 8), 479 &data, sizeof(data)); 480 if (err < 0) { 481 dev_warn(&dev->dev, "%d:%d: cannot get freq (v2/v3): err %d\n", 482 iface, altsetting, err); 483 return 0; 484 } 485 486 return le32_to_cpu(data); 487 } 488 489 static int set_sample_rate_v2v3(struct snd_usb_audio *chip, int iface, 490 struct usb_host_interface *alts, 491 struct audioformat *fmt, int rate) 492 { 493 struct usb_device *dev = chip->dev; 494 __le32 data; 495 int err, cur_rate, prev_rate; 496 int clock; 497 bool writeable; 498 u32 bmControls; 499 500 /* First, try to find a valid clock. This may trigger 501 * automatic clock selection if the current clock is not 502 * valid. 503 */ 504 clock = snd_usb_clock_find_source(chip, fmt->protocol, 505 fmt->clock, true); 506 if (clock < 0) { 507 /* We did not find a valid clock, but that might be 508 * because the current sample rate does not match an 509 * external clock source. Try again without validation 510 * and we will do another validation after setting the 511 * rate. 512 */ 513 clock = snd_usb_clock_find_source(chip, fmt->protocol, 514 fmt->clock, false); 515 if (clock < 0) 516 return clock; 517 } 518 519 prev_rate = get_sample_rate_v2v3(chip, iface, fmt->altsetting, clock); 520 if (prev_rate == rate) 521 goto validation; 522 523 if (fmt->protocol == UAC_VERSION_3) { 524 struct uac3_clock_source_descriptor *cs_desc; 525 526 cs_desc = snd_usb_find_clock_source_v3(chip->ctrl_intf, clock); 527 bmControls = le32_to_cpu(cs_desc->bmControls); 528 } else { 529 struct uac_clock_source_descriptor *cs_desc; 530 531 cs_desc = snd_usb_find_clock_source(chip->ctrl_intf, clock); 532 bmControls = cs_desc->bmControls; 533 } 534 535 writeable = uac_v2v3_control_is_writeable(bmControls, 536 UAC2_CS_CONTROL_SAM_FREQ); 537 if (writeable) { 538 data = cpu_to_le32(rate); 539 err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC2_CS_CUR, 540 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT, 541 UAC2_CS_CONTROL_SAM_FREQ << 8, 542 snd_usb_ctrl_intf(chip) | (clock << 8), 543 &data, sizeof(data)); 544 if (err < 0) { 545 usb_audio_err(chip, 546 "%d:%d: cannot set freq %d (v2/v3): err %d\n", 547 iface, fmt->altsetting, rate, err); 548 return err; 549 } 550 551 cur_rate = get_sample_rate_v2v3(chip, iface, 552 fmt->altsetting, clock); 553 } else { 554 cur_rate = prev_rate; 555 } 556 557 if (cur_rate != rate) { 558 if (!writeable) { 559 usb_audio_warn(chip, 560 "%d:%d: freq mismatch (RO clock): req %d, clock runs @%d\n", 561 iface, fmt->altsetting, rate, cur_rate); 562 return -ENXIO; 563 } 564 usb_audio_dbg(chip, 565 "current rate %d is different from the runtime rate %d\n", 566 cur_rate, rate); 567 } 568 569 /* Some devices doesn't respond to sample rate changes while the 570 * interface is active. */ 571 if (rate != prev_rate) { 572 usb_set_interface(dev, iface, 0); 573 snd_usb_set_interface_quirk(dev); 574 usb_set_interface(dev, iface, fmt->altsetting); 575 snd_usb_set_interface_quirk(dev); 576 } 577 578 validation: 579 /* validate clock after rate change */ 580 if (!uac_clock_source_is_valid(chip, fmt->protocol, clock)) 581 return -ENXIO; 582 return 0; 583 } 584 585 int snd_usb_init_sample_rate(struct snd_usb_audio *chip, int iface, 586 struct usb_host_interface *alts, 587 struct audioformat *fmt, int rate) 588 { 589 switch (fmt->protocol) { 590 case UAC_VERSION_1: 591 default: 592 return set_sample_rate_v1(chip, iface, alts, fmt, rate); 593 594 case UAC_VERSION_3: 595 if (chip->badd_profile >= UAC3_FUNCTION_SUBCLASS_GENERIC_IO) { 596 if (rate != UAC3_BADD_SAMPLING_RATE) 597 return -ENXIO; 598 else 599 return 0; 600 } 601 /* fall through */ 602 case UAC_VERSION_2: 603 return set_sample_rate_v2v3(chip, iface, alts, fmt, rate); 604 } 605 } 606 607