drivers/clk/clk-uclass.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Copyright (C) 2015 Google, Inc
   4  * Written by Simon Glass <sjg@chromium.org>
   5  * Copyright (c) 2016, NVIDIA CORPORATION.
   6  * Copyright (c) 2018, Theobroma Systems Design und Consulting GmbH
   7  */
   8
   9 #include <common.h>
  10 #include <clk.h>
  11 #include <clk-uclass.h>
  12 #include <dm.h>
  13 #include <dt-structs.h>
  14 #include <errno.h>
  15 #include <log.h>
  16 #include <malloc.h>
  17 #include <dm/device-internal.h>
  18 #include <dm/devres.h>
  19 #include <dm/read.h>
  20 #include <linux/bug.h>
  21 #include <linux/clk-provider.h>
  22 #include <linux/err.h>
  23
  24 static inline const struct clk_ops *clk_dev_ops(struct udevice *dev)
  25 {
  26         return (const struct clk_ops *)dev->driver->ops;
  27 }
  28
  29 struct clk *dev_get_clk_ptr(struct udevice *dev)
  30 {
  31         return (struct clk *)dev_get_uclass_priv(dev);
  32 }
  33
  34 #if CONFIG_IS_ENABLED(OF_CONTROL)
  35 # if CONFIG_IS_ENABLED(OF_PLATDATA)
  36 int clk_get_by_driver_info(struct udevice *dev, struct phandle_1_arg *cells,
  37                            struct clk *clk)
  38 {
  39         int ret;
  40
  41         ret = device_get_by_driver_info_idx(cells->idx, &clk->dev);
  42         if (ret)
  43                 return ret;
  44         clk->id = cells->arg[0];
  45
  46         return 0;
  47 }
  48 # else
  49 static int clk_of_xlate_default(struct clk *clk,
  50                                 struct ofnode_phandle_args *args)
  51 {
  52         debug("%s(clk=%p)\n", __func__, clk);
  53
  54         if (args->args_count > 1) {
  55                 debug("Invaild args_count: %d\n", args->args_count);
  56                 return -EINVAL;
  57         }
  58
  59         if (args->args_count)
  60                 clk->id = args->args[0];
  61         else
  62                 clk->id = 0;
  63
  64         clk->data = 0;
  65
  66         return 0;
  67 }
  68
  69 static int clk_get_by_index_tail(int ret, ofnode node,
  70                                  struct ofnode_phandle_args *args,
  71                                  const char *list_name, int index,
  72                                  struct clk *clk)
  73 {
  74         struct udevice *dev_clk;
  75         const struct clk_ops *ops;
  76
  77         assert(clk);
  78         clk->dev = NULL;
  79         if (ret)
  80                 goto err;
  81
  82         ret = uclass_get_device_by_ofnode(UCLASS_CLK, args->node, &dev_clk);
  83         if (ret) {
  84                 debug("%s: uclass_get_device_by_of_offset failed: err=%d\n",
  85                       __func__, ret);
  86                 return ret;
  87         }
  88
  89         clk->dev = dev_clk;
  90
  91         ops = clk_dev_ops(dev_clk);
  92
  93         if (ops->of_xlate)
  94                 ret = ops->of_xlate(clk, args);
  95         else
  96                 ret = clk_of_xlate_default(clk, args);
  97         if (ret) {
  98                 debug("of_xlate() failed: %d\n", ret);
  99                 return ret;
 100         }
 101
 102         return clk_request(dev_clk, clk);
 103 err:
 104         debug("%s: Node '%s', property '%s', failed to request CLK index %d: %d\n",
 105               __func__, ofnode_get_name(node), list_name, index, ret);
 106         return ret;
 107 }
 108
 109 static int clk_get_by_indexed_prop(struct udevice *dev, const char *prop_name,
 110                                    int index, struct clk *clk)
 111 {
 112         int ret;
 113         struct ofnode_phandle_args args;
 114
 115         debug("%s(dev=%p, index=%d, clk=%p)\n", __func__, dev, index, clk);
 116
 117         assert(clk);
 118         clk->dev = NULL;
 119
 120         ret = dev_read_phandle_with_args(dev, prop_name, "#clock-cells", 0,
 121                                          index, &args);
 122         if (ret) {
 123                 debug("%s: fdtdec_parse_phandle_with_args failed: err=%d\n",
 124                       __func__, ret);
 125                 return ret;
 126         }
 127
 128
 129         return clk_get_by_index_tail(ret, dev_ofnode(dev), &args, "clocks",
 130                                      index, clk);
 131 }
 132
 133 int clk_get_by_index(struct udevice *dev, int index, struct clk *clk)
 134 {
 135         struct ofnode_phandle_args args;
 136         int ret;
 137
 138         ret = dev_read_phandle_with_args(dev, "clocks", "#clock-cells", 0,
 139                                          index, &args);
 140
 141         return clk_get_by_index_tail(ret, dev_ofnode(dev), &args, "clocks",
 142                                      index, clk);
 143 }
 144
 145 int clk_get_by_index_nodev(ofnode node, int index, struct clk *clk)
 146 {
 147         struct ofnode_phandle_args args;
 148         int ret;
 149
 150         ret = ofnode_parse_phandle_with_args(node, "clocks", "#clock-cells", 0,
 151                                              index, &args);
 152
 153         return clk_get_by_index_tail(ret, node, &args, "clocks",
 154                                      index, clk);
 155 }
 156
 157 int clk_get_bulk(struct udevice *dev, struct clk_bulk *bulk)
 158 {
 159         int i, ret, err, count;
 160
 161         bulk->count = 0;
 162
 163         count = dev_count_phandle_with_args(dev, "clocks", "#clock-cells", 0);
 164         if (count < 1)
 165                 return count;
 166
 167         bulk->clks = devm_kcalloc(dev, count, sizeof(struct clk), GFP_KERNEL);
 168         if (!bulk->clks)
 169                 return -ENOMEM;
 170
 171         for (i = 0; i < count; i++) {
 172                 ret = clk_get_by_index(dev, i, &bulk->clks[i]);
 173                 if (ret < 0)
 174                         goto bulk_get_err;
 175
 176                 ++bulk->count;
 177         }
 178
 179         return 0;
 180
 181 bulk_get_err:
 182         err = clk_release_all(bulk->clks, bulk->count);
 183         if (err)
 184                 debug("%s: could release all clocks for %p\n",
 185                       __func__, dev);
 186
 187         return ret;
 188 }
 189
 190 static struct clk *clk_set_default_get_by_id(struct clk *clk)
 191 {
 192         struct clk *c = clk;
 193
 194         if (CONFIG_IS_ENABLED(CLK_CCF)) {
 195                 int ret = clk_get_by_id(clk->id, &c);
 196
 197                 if (ret) {
 198                         debug("%s(): could not get parent clock pointer, id %lu\n",
 199                               __func__, clk->id);
 200                         ERR_PTR(ret);
 201                 }
 202         }
 203
 204         return c;
 205 }
 206
 207 static int clk_set_default_parents(struct udevice *dev, int stage)
 208 {
 209         struct clk clk, parent_clk, *c, *p;
 210         int index;
 211         int num_parents;
 212         int ret;
 213
 214         num_parents = dev_count_phandle_with_args(dev, "assigned-clock-parents",
 215                                                   "#clock-cells", 0);
 216         if (num_parents < 0) {
 217                 debug("%s: could not read assigned-clock-parents for %p\n",
 218                       __func__, dev);
 219                 return 0;
 220         }
 221
 222         for (index = 0; index < num_parents; index++) {
 223                 ret = clk_get_by_indexed_prop(dev, "assigned-clock-parents",
 224                                               index, &parent_clk);
 225                 /* If -ENOENT, this is a no-op entry */
 226                 if (ret == -ENOENT)
 227                         continue;
 228
 229                 if (ret) {
 230                         debug("%s: could not get parent clock %d for %s\n",
 231                               __func__, index, dev_read_name(dev));
 232                         return ret;
 233                 }
 234
 235                 p = clk_set_default_get_by_id(&parent_clk);
 236                 if (IS_ERR(p))
 237                         return PTR_ERR(p);
 238
 239                 ret = clk_get_by_indexed_prop(dev, "assigned-clocks",
 240                                               index, &clk);
 241                 if (ret) {
 242                         debug("%s: could not get assigned clock %d for %s\n",
 243                               __func__, index, dev_read_name(dev));
 244                         return ret;
 245                 }
 246
 247                 /* This is clk provider device trying to reparent itself
 248                  * It cannot be done right now but need to wait after the
 249                  * device is probed
 250                  */
 251                 if (stage == 0 && clk.dev == dev)
 252                         continue;
 253
 254                 if (stage > 0 && clk.dev != dev)
 255                         /* do not setup twice the parent clocks */
 256                         continue;
 257
 258                 c = clk_set_default_get_by_id(&clk);
 259                 if (IS_ERR(c))
 260                         return PTR_ERR(c);
 261
 262                 ret = clk_set_parent(c, p);
 263                 /*
 264                  * Not all drivers may support clock-reparenting (as of now).
 265                  * Ignore errors due to this.
 266                  */
 267                 if (ret == -ENOSYS)
 268                         continue;
 269
 270                 if (ret < 0) {
 271                         debug("%s: failed to reparent clock %d for %s\n",
 272                               __func__, index, dev_read_name(dev));
 273                         return ret;
 274                 }
 275         }
 276
 277         return 0;
 278 }
 279
 280 static int clk_set_default_rates(struct udevice *dev, int stage)
 281 {
 282         struct clk clk, *c;
 283         int index;
 284         int num_rates;
 285         int size;
 286         int ret = 0;
 287         u32 *rates = NULL;
 288
 289         size = dev_read_size(dev, "assigned-clock-rates");
 290         if (size < 0)
 291                 return 0;
 292
 293         num_rates = size / sizeof(u32);
 294         rates = calloc(num_rates, sizeof(u32));
 295         if (!rates)
 296                 return -ENOMEM;
 297
 298         ret = dev_read_u32_array(dev, "assigned-clock-rates", rates, num_rates);
 299         if (ret)
 300                 goto fail;
 301
 302         for (index = 0; index < num_rates; index++) {
 303                 /* If 0 is passed, this is a no-op */
 304                 if (!rates[index])
 305                         continue;
 306
 307                 ret = clk_get_by_indexed_prop(dev, "assigned-clocks",
 308                                               index, &clk);
 309                 if (ret) {
 310                         debug("%s: could not get assigned clock %d for %s\n",
 311                               __func__, index, dev_read_name(dev));
 312                         continue;
 313                 }
 314
 315                 /* This is clk provider device trying to program itself
 316                  * It cannot be done right now but need to wait after the
 317                  * device is probed
 318                  */
 319                 if (stage == 0 && clk.dev == dev)
 320                         continue;
 321
 322                 if (stage > 0 && clk.dev != dev)
 323                         /* do not setup twice the parent clocks */
 324                         continue;
 325
 326                 c = clk_set_default_get_by_id(&clk);
 327                 if (IS_ERR(c))
 328                         return PTR_ERR(c);
 329
 330                 ret = clk_set_rate(c, rates[index]);
 331
 332                 if (ret < 0) {
 333                         debug("%s: failed to set rate on clock index %d (%ld) for %s\n",
 334                               __func__, index, clk.id, dev_read_name(dev));
 335                         break;
 336                 }
 337         }
 338
 339 fail:
 340         free(rates);
 341         return ret;
 342 }
 343
 344 int clk_set_defaults(struct udevice *dev, int stage)
 345 {
 346         int ret;
 347
 348         if (!dev_of_valid(dev))
 349                 return 0;
 350
 351         /* If this not in SPL and pre-reloc state, don't take any action. */
 352         if (!(IS_ENABLED(CONFIG_SPL_BUILD) || (gd->flags & GD_FLG_RELOC)))
 353                 return 0;
 354
 355         debug("%s(%s)\n", __func__, dev_read_name(dev));
 356
 357         ret = clk_set_default_parents(dev, stage);
 358         if (ret)
 359                 return ret;
 360
 361         ret = clk_set_default_rates(dev, stage);
 362         if (ret < 0)
 363                 return ret;
 364
 365         return 0;
 366 }
 367
 368 int clk_get_by_name(struct udevice *dev, const char *name, struct clk *clk)
 369 {
 370         int index;
 371
 372         debug("%s(dev=%p, name=%s, clk=%p)\n", __func__, dev, name, clk);
 373         clk->dev = NULL;
 374
 375         index = dev_read_stringlist_search(dev, "clock-names", name);
 376         if (index < 0) {
 377                 debug("fdt_stringlist_search() failed: %d\n", index);
 378                 return index;
 379         }
 380
 381         return clk_get_by_index(dev, index, clk);
 382 }
 383 # endif /* OF_PLATDATA */
 384
 385 int clk_get_by_name_nodev(ofnode node, const char *name, struct clk *clk)
 386 {
 387         int index;
 388
 389         debug("%s(node=%p, name=%s, clk=%p)\n", __func__,
 390                 ofnode_get_name(node), name, clk);
 391         clk->dev = NULL;
 392
 393         index = ofnode_stringlist_search(node, "clock-names", name);
 394         if (index < 0) {
 395                 debug("fdt_stringlist_search() failed: %d\n", index);
 396                 return index;
 397         }
 398
 399         return clk_get_by_index_nodev(node, index, clk);
 400 }
 401
 402 int clk_get_optional_nodev(ofnode node, const char *name, struct clk *clk)
 403 {
 404         int ret;
 405
 406         ret = clk_get_by_name_nodev(node, name, clk);
 407         if (ret == -ENODATA)
 408                 return 0;
 409
 410         return ret;
 411 }
 412
 413 int clk_release_all(struct clk *clk, int count)
 414 {
 415         int i, ret;
 416
 417         for (i = 0; i < count; i++) {
 418                 debug("%s(clk[%d]=%p)\n", __func__, i, &clk[i]);
 419
 420                 /* check if clock has been previously requested */
 421                 if (!clk[i].dev)
 422                         continue;
 423
 424                 ret = clk_disable(&clk[i]);
 425                 if (ret && ret != -ENOSYS)
 426                         return ret;
 427
 428                 ret = clk_free(&clk[i]);
 429                 if (ret && ret != -ENOSYS)
 430                         return ret;
 431         }
 432
 433         return 0;
 434 }
 435
 436 #endif /* OF_CONTROL */
 437
 438 int clk_request(struct udevice *dev, struct clk *clk)
 439 {
 440         const struct clk_ops *ops;
 441
 442         debug("%s(dev=%p, clk=%p)\n", __func__, dev, clk);
 443         if (!clk)
 444                 return 0;
 445         ops = clk_dev_ops(dev);
 446
 447         clk->dev = dev;
 448
 449         if (!ops->request)
 450                 return 0;
 451
 452         return ops->request(clk);
 453 }
 454
 455 int clk_free(struct clk *clk)
 456 {
 457         const struct clk_ops *ops;
 458
 459         debug("%s(clk=%p)\n", __func__, clk);
 460         if (!clk_valid(clk))
 461                 return 0;
 462         ops = clk_dev_ops(clk->dev);
 463
 464         if (!ops->rfree)
 465                 return 0;
 466
 467         return ops->rfree(clk);
 468 }
 469
 470 ulong clk_get_rate(struct clk *clk)
 471 {
 472         const struct clk_ops *ops;
 473
 474         debug("%s(clk=%p)\n", __func__, clk);
 475         if (!clk_valid(clk))
 476                 return 0;
 477         ops = clk_dev_ops(clk->dev);
 478
 479         if (!ops->get_rate)
 480                 return -ENOSYS;
 481
 482         return ops->get_rate(clk);
 483 }
 484
 485 struct clk *clk_get_parent(struct clk *clk)
 486 {
 487         struct udevice *pdev;
 488         struct clk *pclk;
 489
 490         debug("%s(clk=%p)\n", __func__, clk);
 491         if (!clk_valid(clk))
 492                 return NULL;
 493
 494         pdev = dev_get_parent(clk->dev);
 495         pclk = dev_get_clk_ptr(pdev);
 496         if (!pclk)
 497                 return ERR_PTR(-ENODEV);
 498
 499         return pclk;
 500 }
 501
 502 long long clk_get_parent_rate(struct clk *clk)
 503 {
 504         const struct clk_ops *ops;
 505         struct clk *pclk;
 506
 507         debug("%s(clk=%p)\n", __func__, clk);
 508         if (!clk_valid(clk))
 509                 return 0;
 510
 511         pclk = clk_get_parent(clk);
 512         if (IS_ERR(pclk))
 513                 return -ENODEV;
 514
 515         ops = clk_dev_ops(pclk->dev);
 516         if (!ops->get_rate)
 517                 return -ENOSYS;
 518
 519         /* Read the 'rate' if not already set or if proper flag set*/
 520         if (!pclk->rate || pclk->flags & CLK_GET_RATE_NOCACHE)
 521                 pclk->rate = clk_get_rate(pclk);
 522
 523         return pclk->rate;
 524 }
 525
 526 ulong clk_set_rate(struct clk *clk, ulong rate)
 527 {
 528         const struct clk_ops *ops;
 529
 530         debug("%s(clk=%p, rate=%lu)\n", __func__, clk, rate);
 531         if (!clk_valid(clk))
 532                 return 0;
 533         ops = clk_dev_ops(clk->dev);
 534
 535         if (!ops->set_rate)
 536                 return -ENOSYS;
 537
 538         return ops->set_rate(clk, rate);
 539 }
 540
 541 int clk_set_parent(struct clk *clk, struct clk *parent)
 542 {
 543         const struct clk_ops *ops;
 544         int ret;
 545
 546         debug("%s(clk=%p, parent=%p)\n", __func__, clk, parent);
 547         if (!clk_valid(clk))
 548                 return 0;
 549         ops = clk_dev_ops(clk->dev);
 550
 551         if (!ops->set_parent)
 552                 return -ENOSYS;
 553
 554         ret = ops->set_parent(clk, parent);
 555         if (ret)
 556                 return ret;
 557
 558         if (CONFIG_IS_ENABLED(CLK_CCF))
 559                 ret = device_reparent(clk->dev, parent->dev);
 560
 561         return ret;
 562 }
 563
 564 int clk_enable(struct clk *clk)
 565 {
 566         const struct clk_ops *ops;
 567         struct clk *clkp = NULL;
 568         int ret;
 569
 570         debug("%s(clk=%p)\n", __func__, clk);
 571         if (!clk_valid(clk))
 572                 return 0;
 573         ops = clk_dev_ops(clk->dev);
 574
 575         if (CONFIG_IS_ENABLED(CLK_CCF)) {
 576                 /* Take id 0 as a non-valid clk, such as dummy */
 577                 if (clk->id && !clk_get_by_id(clk->id, &clkp)) {
 578                         if (clkp->enable_count) {
 579                                 clkp->enable_count++;
 580                                 return 0;
 581                         }
 582                         if (clkp->dev->parent &&
 583                             device_get_uclass_id(clkp->dev) == UCLASS_CLK) {
 584                                 ret = clk_enable(dev_get_clk_ptr(clkp->dev->parent));
 585                                 if (ret) {
 586                                         printf("Enable %s failed\n",
 587                                                clkp->dev->parent->name);
 588                                         return ret;
 589                                 }
 590                         }
 591                 }
 592
 593                 if (ops->enable) {
 594                         ret = ops->enable(clk);
 595                         if (ret) {
 596                                 printf("Enable %s failed\n", clk->dev->name);
 597                                 return ret;
 598                         }
 599                 }
 600                 if (clkp)
 601                         clkp->enable_count++;
 602         } else {
 603                 if (!ops->enable)
 604                         return -ENOSYS;
 605                 return ops->enable(clk);
 606         }
 607
 608         return 0;
 609 }
 610
 611 int clk_enable_bulk(struct clk_bulk *bulk)
 612 {
 613         int i, ret;
 614
 615         for (i = 0; i < bulk->count; i++) {
 616                 ret = clk_enable(&bulk->clks[i]);
 617                 if (ret < 0 && ret != -ENOSYS)
 618                         return ret;
 619         }
 620
 621         return 0;
 622 }
 623
 624 int clk_disable(struct clk *clk)
 625 {
 626         const struct clk_ops *ops;
 627         struct clk *clkp = NULL;
 628         int ret;
 629
 630         debug("%s(clk=%p)\n", __func__, clk);
 631         if (!clk_valid(clk))
 632                 return 0;
 633         ops = clk_dev_ops(clk->dev);
 634
 635         if (CONFIG_IS_ENABLED(CLK_CCF)) {
 636                 if (clk->id && !clk_get_by_id(clk->id, &clkp)) {
 637                         if (clkp->flags & CLK_IS_CRITICAL)
 638                                 return 0;
 639
 640                         if (clkp->enable_count == 0) {
 641                                 printf("clk %s already disabled\n",
 642                                        clkp->dev->name);
 643                                 return 0;
 644                         }
 645
 646                         if (--clkp->enable_count > 0)
 647                                 return 0;
 648                 }
 649
 650                 if (ops->disable) {
 651                         ret = ops->disable(clk);
 652                         if (ret)
 653                                 return ret;
 654                 }
 655
 656                 if (clkp && clkp->dev->parent &&
 657                     device_get_uclass_id(clkp->dev) == UCLASS_CLK) {
 658                         ret = clk_disable(dev_get_clk_ptr(clkp->dev->parent));
 659                         if (ret) {
 660                                 printf("Disable %s failed\n",
 661                                        clkp->dev->parent->name);
 662                                 return ret;
 663                         }
 664                 }
 665         } else {
 666                 if (!ops->disable)
 667                         return -ENOSYS;
 668
 669                 return ops->disable(clk);
 670         }
 671
 672         return 0;
 673 }
 674
 675 int clk_disable_bulk(struct clk_bulk *bulk)
 676 {
 677         int i, ret;
 678
 679         for (i = 0; i < bulk->count; i++) {
 680                 ret = clk_disable(&bulk->clks[i]);
 681                 if (ret < 0 && ret != -ENOSYS)
 682                         return ret;
 683         }
 684
 685         return 0;
 686 }
 687
 688 int clk_get_by_id(ulong id, struct clk **clkp)
 689 {
 690         struct udevice *dev;
 691         struct uclass *uc;
 692         int ret;
 693
 694         ret = uclass_get(UCLASS_CLK, &uc);
 695         if (ret)
 696                 return ret;
 697
 698         uclass_foreach_dev(dev, uc) {
 699                 struct clk *clk = dev_get_clk_ptr(dev);
 700
 701                 if (clk && clk->id == id) {
 702                         *clkp = clk;
 703                         return 0;
 704                 }
 705         }
 706
 707         return -ENOENT;
 708 }
 709
 710 bool clk_is_match(const struct clk *p, const struct clk *q)
 711 {
 712         /* trivial case: identical struct clk's or both NULL */
 713         if (p == q)
 714                 return true;
 715
 716         /* trivial case #2: on the clk pointer is NULL */
 717         if (!p || !q)
 718                 return false;
 719
 720         /* same device, id and data */
 721         if (p->dev == q->dev && p->id == q->id && p->data == q->data)
 722                 return true;
 723
 724         return false;
 725 }
 726
 727 static void devm_clk_release(struct udevice *dev, void *res)
 728 {
 729         clk_free(res);
 730 }
 731
 732 static int devm_clk_match(struct udevice *dev, void *res, void *data)
 733 {
 734         return res == data;
 735 }
 736
 737 struct clk *devm_clk_get(struct udevice *dev, const char *id)
 738 {
 739         int rc;
 740         struct clk *clk;
 741
 742         clk = devres_alloc(devm_clk_release, sizeof(struct clk), __GFP_ZERO);
 743         if (unlikely(!clk))
 744                 return ERR_PTR(-ENOMEM);
 745
 746         rc = clk_get_by_name(dev, id, clk);
 747         if (rc)
 748                 return ERR_PTR(rc);
 749
 750         devres_add(dev, clk);
 751         return clk;
 752 }
 753
 754 struct clk *devm_clk_get_optional(struct udevice *dev, const char *id)
 755 {
 756         struct clk *clk = devm_clk_get(dev, id);
 757
 758         if (PTR_ERR(clk) == -ENODATA)
 759                 return NULL;
 760
 761         return clk;
 762 }
 763
 764 void devm_clk_put(struct udevice *dev, struct clk *clk)
 765 {
 766         int rc;
 767
 768         if (!clk)
 769                 return;
 770
 771         rc = devres_release(dev, devm_clk_release, devm_clk_match, clk);
 772         WARN_ON(rc);
 773 }
 774
 775 int clk_uclass_post_probe(struct udevice *dev)
 776 {
 777         /*
 778          * when a clock provider is probed. Call clk_set_defaults()
 779          * also after the device is probed. This takes care of cases
 780          * where the DT is used to setup default parents and rates
 781          * using assigned-clocks
 782          */
 783         clk_set_defaults(dev, 1);
 784
 785         return 0;
 786 }
 787
 788 UCLASS_DRIVER(clk) = {
 789         .id             = UCLASS_CLK,
 790         .name           = "clk",
 791         .post_probe     = clk_uclass_post_probe,
 792 };