sound/usb/clock.c

   1 /*
   2  *   Clock domain and sample rate management functions
   3  *
   4  *   This program is free software; you can redistribute it and/or modify
   5  *   it under the terms of the GNU General Public License as published by
   6  *   the Free Software Foundation; either version 2 of the License, or
   7  *   (at your option) any later version.
   8  *
   9  *   This program is distributed in the hope that it will be useful,
  10  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  *   GNU General Public License for more details.
  13  *
  14  *   You should have received a copy of the GNU General Public License
  15  *   along with this program; if not, write to the Free Software
  16  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  17  *
  18  */
  19
  20 #include <linux/bitops.h>
  21 #include <linux/init.h>
  22 #include <linux/string.h>
  23 #include <linux/usb.h>
  24 #include <linux/usb/audio.h>
  25 #include <linux/usb/audio-v2.h>
  26 #include <linux/usb/audio-v3.h>
  27
  28 #include <sound/core.h>
  29 #include <sound/info.h>
  30 #include <sound/pcm.h>
  31
  32 #include "usbaudio.h"
  33 #include "card.h"
  34 #include "helper.h"
  35 #include "clock.h"
  36 #include "quirks.h"
  37
  38 static void *find_uac_clock_desc(struct usb_host_interface *iface, int id,
  39                                  bool (*validator)(void *, int), u8 type)
  40 {
  41         void *cs = NULL;
  42
  43         while ((cs = snd_usb_find_csint_desc(iface->extra, iface->extralen,
  44                                              cs, type))) {
  45                 if (validator(cs, id))
  46                         return cs;
  47         }
  48
  49         return NULL;
  50 }
  51
  52 static bool validate_clock_source_v2(void *p, int id)
  53 {
  54         struct uac_clock_source_descriptor *cs = p;
  55         return cs->bLength == sizeof(*cs) && cs->bClockID == id;
  56 }
  57
  58 static bool validate_clock_source_v3(void *p, int id)
  59 {
  60         struct uac3_clock_source_descriptor *cs = p;
  61         return cs->bLength == sizeof(*cs) && cs->bClockID == id;
  62 }
  63
  64 static bool validate_clock_selector_v2(void *p, int id)
  65 {
  66         struct uac_clock_selector_descriptor *cs = p;
  67         return cs->bLength >= sizeof(*cs) && cs->bClockID == id &&
  68                 cs->bLength == 7 + cs->bNrInPins;
  69 }
  70
  71 static bool validate_clock_selector_v3(void *p, int id)
  72 {
  73         struct uac3_clock_selector_descriptor *cs = p;
  74         return cs->bLength >= sizeof(*cs) && cs->bClockID == id &&
  75                 cs->bLength == 11 + cs->bNrInPins;
  76 }
  77
  78 static bool validate_clock_multiplier_v2(void *p, int id)
  79 {
  80         struct uac_clock_multiplier_descriptor *cs = p;
  81         return cs->bLength == sizeof(*cs) && cs->bClockID == id;
  82 }
  83
  84 static bool validate_clock_multiplier_v3(void *p, int id)
  85 {
  86         struct uac3_clock_multiplier_descriptor *cs = p;
  87         return cs->bLength == sizeof(*cs) && cs->bClockID == id;
  88 }
  89
  90 #define DEFINE_FIND_HELPER(name, obj, validator, type)          \
  91 static obj *name(struct usb_host_interface *iface, int id)      \
  92 {                                                               \
  93         return find_uac_clock_desc(iface, id, validator, type); \
  94 }
  95
  96 DEFINE_FIND_HELPER(snd_usb_find_clock_source,
  97                    struct uac_clock_source_descriptor,
  98                    validate_clock_source_v2, UAC2_CLOCK_SOURCE);
  99 DEFINE_FIND_HELPER(snd_usb_find_clock_source_v3,
 100                    struct uac3_clock_source_descriptor,
 101                    validate_clock_source_v3, UAC3_CLOCK_SOURCE);
 102
 103 DEFINE_FIND_HELPER(snd_usb_find_clock_selector,
 104                    struct uac_clock_selector_descriptor,
 105                    validate_clock_selector_v2, UAC2_CLOCK_SELECTOR);
 106 DEFINE_FIND_HELPER(snd_usb_find_clock_selector_v3,
 107                    struct uac3_clock_selector_descriptor,
 108                    validate_clock_selector_v3, UAC3_CLOCK_SELECTOR);
 109
 110 DEFINE_FIND_HELPER(snd_usb_find_clock_multiplier,
 111                    struct uac_clock_multiplier_descriptor,
 112                    validate_clock_multiplier_v2, UAC2_CLOCK_MULTIPLIER);
 113 DEFINE_FIND_HELPER(snd_usb_find_clock_multiplier_v3,
 114                    struct uac3_clock_multiplier_descriptor,
 115                    validate_clock_multiplier_v3, UAC3_CLOCK_MULTIPLIER);
 116
 117 static int uac_clock_selector_get_val(struct snd_usb_audio *chip, int selector_id)
 118 {
 119         unsigned char buf;
 120         int ret;
 121
 122         ret = snd_usb_ctl_msg(chip->dev, usb_rcvctrlpipe(chip->dev, 0),
 123                               UAC2_CS_CUR,
 124                               USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
 125                               UAC2_CX_CLOCK_SELECTOR << 8,
 126                               snd_usb_ctrl_intf(chip) | (selector_id << 8),
 127                               &buf, sizeof(buf));
 128
 129         if (ret < 0)
 130                 return ret;
 131
 132         return buf;
 133 }
 134
 135 static int uac_clock_selector_set_val(struct snd_usb_audio *chip, int selector_id,
 136                                         unsigned char pin)
 137 {
 138         int ret;
 139
 140         ret = snd_usb_ctl_msg(chip->dev, usb_sndctrlpipe(chip->dev, 0),
 141                               UAC2_CS_CUR,
 142                               USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_OUT,
 143                               UAC2_CX_CLOCK_SELECTOR << 8,
 144                               snd_usb_ctrl_intf(chip) | (selector_id << 8),
 145                               &pin, sizeof(pin));
 146         if (ret < 0)
 147                 return ret;
 148
 149         if (ret != sizeof(pin)) {
 150                 usb_audio_err(chip,
 151                         "setting selector (id %d) unexpected length %d\n",
 152                         selector_id, ret);
 153                 return -EINVAL;
 154         }
 155
 156         ret = uac_clock_selector_get_val(chip, selector_id);
 157         if (ret < 0)
 158                 return ret;
 159
 160         if (ret != pin) {
 161                 usb_audio_err(chip,
 162                         "setting selector (id %d) to %x failed (current: %d)\n",
 163                         selector_id, pin, ret);
 164                 return -EINVAL;
 165         }
 166
 167         return ret;
 168 }
 169
 170 static bool uac_clock_source_is_valid(struct snd_usb_audio *chip,
 171                                       int protocol,
 172                                       int source_id)
 173 {
 174         int err;
 175         unsigned char data;
 176         struct usb_device *dev = chip->dev;
 177         u32 bmControls;
 178
 179         if (protocol == UAC_VERSION_3) {
 180                 struct uac3_clock_source_descriptor *cs_desc =
 181                         snd_usb_find_clock_source_v3(chip->ctrl_intf, source_id);
 182
 183                 if (!cs_desc)
 184                         return 0;
 185                 bmControls = le32_to_cpu(cs_desc->bmControls);
 186         } else { /* UAC_VERSION_1/2 */
 187                 struct uac_clock_source_descriptor *cs_desc =
 188                         snd_usb_find_clock_source(chip->ctrl_intf, source_id);
 189
 190                 if (!cs_desc)
 191                         return 0;
 192                 bmControls = cs_desc->bmControls;
 193         }
 194
 195         /* If a clock source can't tell us whether it's valid, we assume it is */
 196         if (!uac_v2v3_control_is_readable(bmControls,
 197                                       UAC2_CS_CONTROL_CLOCK_VALID))
 198                 return 1;
 199
 200         err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_CUR,
 201                               USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
 202                               UAC2_CS_CONTROL_CLOCK_VALID << 8,
 203                               snd_usb_ctrl_intf(chip) | (source_id << 8),
 204                               &data, sizeof(data));
 205
 206         if (err < 0) {
 207                 dev_warn(&dev->dev,
 208                          "%s(): cannot get clock validity for id %d\n",
 209                            __func__, source_id);
 210                 return 0;
 211         }
 212
 213         return !!data;
 214 }
 215
 216 static int __uac_clock_find_source(struct snd_usb_audio *chip, int entity_id,
 217                                    unsigned long *visited, bool validate)
 218 {
 219         struct uac_clock_source_descriptor *source;
 220         struct uac_clock_selector_descriptor *selector;
 221         struct uac_clock_multiplier_descriptor *multiplier;
 222
 223         entity_id &= 0xff;
 224
 225         if (test_and_set_bit(entity_id, visited)) {
 226                 usb_audio_warn(chip,
 227                          "%s(): recursive clock topology detected, id %d.\n",
 228                          __func__, entity_id);
 229                 return -EINVAL;
 230         }
 231
 232         /* first, see if the ID we're looking for is a clock source already */
 233         source = snd_usb_find_clock_source(chip->ctrl_intf, entity_id);
 234         if (source) {
 235                 entity_id = source->bClockID;
 236                 if (validate && !uac_clock_source_is_valid(chip, UAC_VERSION_2,
 237                                                                 entity_id)) {
 238                         usb_audio_err(chip,
 239                                 "clock source %d is not valid, cannot use\n",
 240                                 entity_id);
 241                         return -ENXIO;
 242                 }
 243                 return entity_id;
 244         }
 245
 246         selector = snd_usb_find_clock_selector(chip->ctrl_intf, entity_id);
 247         if (selector) {
 248                 int ret, i, cur;
 249
 250                 /* the entity ID we are looking for is a selector.
 251                  * find out what it currently selects */
 252                 ret = uac_clock_selector_get_val(chip, selector->bClockID);
 253                 if (ret < 0)
 254                         return ret;
 255
 256                 /* Selector values are one-based */
 257
 258                 if (ret > selector->bNrInPins || ret < 1) {
 259                         usb_audio_err(chip,
 260                                 "%s(): selector reported illegal value, id %d, ret %d\n",
 261                                 __func__, selector->bClockID, ret);
 262
 263                         return -EINVAL;
 264                 }
 265
 266                 cur = ret;
 267                 ret = __uac_clock_find_source(chip, selector->baCSourceID[ret - 1],
 268                                                visited, validate);
 269                 if (!validate || ret > 0 || !chip->autoclock)
 270                         return ret;
 271
 272                 /* The current clock source is invalid, try others. */
 273                 for (i = 1; i <= selector->bNrInPins; i++) {
 274                         int err;
 275
 276                         if (i == cur)
 277                                 continue;
 278
 279                         ret = __uac_clock_find_source(chip, selector->baCSourceID[i - 1],
 280                                 visited, true);
 281                         if (ret < 0)
 282                                 continue;
 283
 284                         err = uac_clock_selector_set_val(chip, entity_id, i);
 285                         if (err < 0)
 286                                 continue;
 287
 288                         usb_audio_info(chip,
 289                                  "found and selected valid clock source %d\n",
 290                                  ret);
 291                         return ret;
 292                 }
 293
 294                 return -ENXIO;
 295         }
 296
 297         /* FIXME: multipliers only act as pass-thru element for now */
 298         multiplier = snd_usb_find_clock_multiplier(chip->ctrl_intf, entity_id);
 299         if (multiplier)
 300                 return __uac_clock_find_source(chip, multiplier->bCSourceID,
 301                                                 visited, validate);
 302
 303         return -EINVAL;
 304 }
 305
 306 static int __uac3_clock_find_source(struct snd_usb_audio *chip, int entity_id,
 307                                    unsigned long *visited, bool validate)
 308 {
 309         struct uac3_clock_source_descriptor *source;
 310         struct uac3_clock_selector_descriptor *selector;
 311         struct uac3_clock_multiplier_descriptor *multiplier;
 312
 313         entity_id &= 0xff;
 314
 315         if (test_and_set_bit(entity_id, visited)) {
 316                 usb_audio_warn(chip,
 317                          "%s(): recursive clock topology detected, id %d.\n",
 318                          __func__, entity_id);
 319                 return -EINVAL;
 320         }
 321
 322         /* first, see if the ID we're looking for is a clock source already */
 323         source = snd_usb_find_clock_source_v3(chip->ctrl_intf, entity_id);
 324         if (source) {
 325                 entity_id = source->bClockID;
 326                 if (validate && !uac_clock_source_is_valid(chip, UAC_VERSION_3,
 327                                                                 entity_id)) {
 328                         usb_audio_err(chip,
 329                                 "clock source %d is not valid, cannot use\n",
 330                                 entity_id);
 331                         return -ENXIO;
 332                 }
 333                 return entity_id;
 334         }
 335
 336         selector = snd_usb_find_clock_selector_v3(chip->ctrl_intf, entity_id);
 337         if (selector) {
 338                 int ret, i, cur;
 339
 340                 /* the entity ID we are looking for is a selector.
 341                  * find out what it currently selects */
 342                 ret = uac_clock_selector_get_val(chip, selector->bClockID);
 343                 if (ret < 0)
 344                         return ret;
 345
 346                 /* Selector values are one-based */
 347
 348                 if (ret > selector->bNrInPins || ret < 1) {
 349                         usb_audio_err(chip,
 350                                 "%s(): selector reported illegal value, id %d, ret %d\n",
 351                                 __func__, selector->bClockID, ret);
 352
 353                         return -EINVAL;
 354                 }
 355
 356                 cur = ret;
 357                 ret = __uac3_clock_find_source(chip, selector->baCSourceID[ret - 1],
 358                                                visited, validate);
 359                 if (!validate || ret > 0 || !chip->autoclock)
 360                         return ret;
 361
 362                 /* The current clock source is invalid, try others. */
 363                 for (i = 1; i <= selector->bNrInPins; i++) {
 364                         int err;
 365
 366                         if (i == cur)
 367                                 continue;
 368
 369                         ret = __uac3_clock_find_source(chip, selector->baCSourceID[i - 1],
 370                                 visited, true);
 371                         if (ret < 0)
 372                                 continue;
 373
 374                         err = uac_clock_selector_set_val(chip, entity_id, i);
 375                         if (err < 0)
 376                                 continue;
 377
 378                         usb_audio_info(chip,
 379                                  "found and selected valid clock source %d\n",
 380                                  ret);
 381                         return ret;
 382                 }
 383
 384                 return -ENXIO;
 385         }
 386
 387         /* FIXME: multipliers only act as pass-thru element for now */
 388         multiplier = snd_usb_find_clock_multiplier_v3(chip->ctrl_intf,
 389                                                       entity_id);
 390         if (multiplier)
 391                 return __uac3_clock_find_source(chip, multiplier->bCSourceID,
 392                                                 visited, validate);
 393
 394         return -EINVAL;
 395 }
 396
 397 /*
 398  * For all kinds of sample rate settings and other device queries,
 399  * the clock source (end-leaf) must be used. However, clock selectors,
 400  * clock multipliers and sample rate converters may be specified as
 401  * clock source input to terminal. This functions walks the clock path
 402  * to its end and tries to find the source.
 403  *
 404  * The 'visited' bitfield is used internally to detect recursive loops.
 405  *
 406  * Returns the clock source UnitID (>=0) on success, or an error.
 407  */
 408 int snd_usb_clock_find_source(struct snd_usb_audio *chip, int protocol,
 409                               int entity_id, bool validate)
 410 {
 411         DECLARE_BITMAP(visited, 256);
 412         memset(visited, 0, sizeof(visited));
 413
 414         switch (protocol) {
 415         case UAC_VERSION_2:
 416                 return __uac_clock_find_source(chip, entity_id, visited,
 417                                                validate);
 418         case UAC_VERSION_3:
 419                 return __uac3_clock_find_source(chip, entity_id, visited,
 420                                                validate);
 421         default:
 422                 return -EINVAL;
 423         }
 424 }
 425
 426 static int set_sample_rate_v1(struct snd_usb_audio *chip, int iface,
 427                               struct usb_host_interface *alts,
 428                               struct audioformat *fmt, int rate)
 429 {
 430         struct usb_device *dev = chip->dev;
 431         unsigned int ep;
 432         unsigned char data[3];
 433         int err, crate;
 434
 435         if (get_iface_desc(alts)->bNumEndpoints < 1)
 436                 return -EINVAL;
 437         ep = get_endpoint(alts, 0)->bEndpointAddress;
 438
 439         /* if endpoint doesn't have sampling rate control, bail out */
 440         if (!(fmt->attributes & UAC_EP_CS_ATTR_SAMPLE_RATE))
 441                 return 0;
 442
 443         data[0] = rate;
 444         data[1] = rate >> 8;
 445         data[2] = rate >> 16;
 446         err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC_SET_CUR,
 447                               USB_TYPE_CLASS | USB_RECIP_ENDPOINT | USB_DIR_OUT,
 448                               UAC_EP_CS_ATTR_SAMPLE_RATE << 8, ep,
 449                               data, sizeof(data));
 450         if (err < 0) {
 451                 dev_err(&dev->dev, "%d:%d: cannot set freq %d to ep %#x\n",
 452                         iface, fmt->altsetting, rate, ep);
 453                 return err;
 454         }
 455
 456         /* Don't check the sample rate for devices which we know don't
 457          * support reading */
 458         if (snd_usb_get_sample_rate_quirk(chip))
 459                 return 0;
 460         /* the firmware is likely buggy, don't repeat to fail too many times */
 461         if (chip->sample_rate_read_error > 2)
 462                 return 0;
 463
 464         err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC_GET_CUR,
 465                               USB_TYPE_CLASS | USB_RECIP_ENDPOINT | USB_DIR_IN,
 466                               UAC_EP_CS_ATTR_SAMPLE_RATE << 8, ep,
 467                               data, sizeof(data));
 468         if (err < 0) {
 469                 dev_err(&dev->dev, "%d:%d: cannot get freq at ep %#x\n",
 470                         iface, fmt->altsetting, ep);
 471                 chip->sample_rate_read_error++;
 472                 return 0; /* some devices don't support reading */
 473         }
 474
 475         crate = data[0] | (data[1] << 8) | (data[2] << 16);
 476         if (crate != rate) {
 477                 dev_warn(&dev->dev, "current rate %d is different from the runtime rate %d\n", crate, rate);
 478                 // runtime->rate = crate;
 479         }
 480
 481         return 0;
 482 }
 483
 484 static int get_sample_rate_v2v3(struct snd_usb_audio *chip, int iface,
 485                               int altsetting, int clock)
 486 {
 487         struct usb_device *dev = chip->dev;
 488         __le32 data;
 489         int err;
 490
 491         err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_CUR,
 492                               USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
 493                               UAC2_CS_CONTROL_SAM_FREQ << 8,
 494                               snd_usb_ctrl_intf(chip) | (clock << 8),
 495                               &data, sizeof(data));
 496         if (err < 0) {
 497                 dev_warn(&dev->dev, "%d:%d: cannot get freq (v2/v3): err %d\n",
 498                          iface, altsetting, err);
 499                 return 0;
 500         }
 501
 502         return le32_to_cpu(data);
 503 }
 504
 505 static int set_sample_rate_v2v3(struct snd_usb_audio *chip, int iface,
 506                               struct usb_host_interface *alts,
 507                               struct audioformat *fmt, int rate)
 508 {
 509         struct usb_device *dev = chip->dev;
 510         __le32 data;
 511         int err, cur_rate, prev_rate;
 512         int clock;
 513         bool writeable;
 514         u32 bmControls;
 515
 516         clock = snd_usb_clock_find_source(chip, fmt->protocol,
 517                                           fmt->clock, true);
 518         if (clock < 0)
 519                 return clock;
 520
 521         prev_rate = get_sample_rate_v2v3(chip, iface, fmt->altsetting, clock);
 522         if (prev_rate == rate)
 523                 return 0;
 524
 525         if (fmt->protocol == UAC_VERSION_3) {
 526                 struct uac3_clock_source_descriptor *cs_desc;
 527
 528                 cs_desc = snd_usb_find_clock_source_v3(chip->ctrl_intf, clock);
 529                 bmControls = le32_to_cpu(cs_desc->bmControls);
 530         } else {
 531                 struct uac_clock_source_descriptor *cs_desc;
 532
 533                 cs_desc = snd_usb_find_clock_source(chip->ctrl_intf, clock);
 534                 bmControls = cs_desc->bmControls;
 535         }
 536
 537         writeable = uac_v2v3_control_is_writeable(bmControls,
 538                                                   UAC2_CS_CONTROL_SAM_FREQ);
 539         if (writeable) {
 540                 data = cpu_to_le32(rate);
 541                 err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC2_CS_CUR,
 542                                       USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT,
 543                                       UAC2_CS_CONTROL_SAM_FREQ << 8,
 544                                       snd_usb_ctrl_intf(chip) | (clock << 8),
 545                                       &data, sizeof(data));
 546                 if (err < 0) {
 547                         usb_audio_err(chip,
 548                                 "%d:%d: cannot set freq %d (v2/v3): err %d\n",
 549                                 iface, fmt->altsetting, rate, err);
 550                         return err;
 551                 }
 552
 553                 cur_rate = get_sample_rate_v2v3(chip, iface,
 554                                                 fmt->altsetting, clock);
 555         } else {
 556                 cur_rate = prev_rate;
 557         }
 558
 559         if (cur_rate != rate) {
 560                 if (!writeable) {
 561                         usb_audio_warn(chip,
 562                                  "%d:%d: freq mismatch (RO clock): req %d, clock runs @%d\n",
 563                                  iface, fmt->altsetting, rate, cur_rate);
 564                         return -ENXIO;
 565                 }
 566                 usb_audio_dbg(chip,
 567                         "current rate %d is different from the runtime rate %d\n",
 568                         cur_rate, rate);
 569         }
 570
 571         /* Some devices doesn't respond to sample rate changes while the
 572          * interface is active. */
 573         if (rate != prev_rate) {
 574                 usb_set_interface(dev, iface, 0);
 575                 snd_usb_set_interface_quirk(dev);
 576                 usb_set_interface(dev, iface, fmt->altsetting);
 577                 snd_usb_set_interface_quirk(dev);
 578         }
 579
 580         return 0;
 581 }
 582
 583 int snd_usb_init_sample_rate(struct snd_usb_audio *chip, int iface,
 584                              struct usb_host_interface *alts,
 585                              struct audioformat *fmt, int rate)
 586 {
 587         switch (fmt->protocol) {
 588         case UAC_VERSION_1:
 589         default:
 590                 return set_sample_rate_v1(chip, iface, alts, fmt, rate);
 591
 592         case UAC_VERSION_3:
 593                 if (chip->badd_profile >= UAC3_FUNCTION_SUBCLASS_GENERIC_IO) {
 594                         if (rate != UAC3_BADD_SAMPLING_RATE)
 595                                 return -ENXIO;
 596                         else
 597                                 return 0;
 598                 }
 599         /* fall through */
 600         case UAC_VERSION_2:
 601                 return set_sample_rate_v2v3(chip, iface, alts, fmt, rate);
 602         }
 603 }
 604