drivers/dpll/dpll_core.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  dpll_core.c - DPLL subsystem kernel-space interface implementation.
   4  *
   5  *  Copyright (c) 2023 Meta Platforms, Inc. and affiliates
   6  *  Copyright (c) 2023 Intel Corporation.
   7  */
   8
   9 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  10
  11 #include <linux/device.h>
  12 #include <linux/err.h>
  13 #include <linux/slab.h>
  14 #include <linux/string.h>
  15
  16 #include "dpll_core.h"
  17 #include "dpll_netlink.h"
  18
  19 /* Mutex lock to protect DPLL subsystem devices and pins */
  20 DEFINE_MUTEX(dpll_lock);
  21
  22 DEFINE_XARRAY_FLAGS(dpll_device_xa, XA_FLAGS_ALLOC);
  23 DEFINE_XARRAY_FLAGS(dpll_pin_xa, XA_FLAGS_ALLOC);
  24
  25 static u32 dpll_device_xa_id;
  26 static u32 dpll_pin_xa_id;
  27
  28 #define ASSERT_DPLL_REGISTERED(d)       \
  29         WARN_ON_ONCE(!xa_get_mark(&dpll_device_xa, (d)->id, DPLL_REGISTERED))
  30 #define ASSERT_DPLL_NOT_REGISTERED(d)   \
  31         WARN_ON_ONCE(xa_get_mark(&dpll_device_xa, (d)->id, DPLL_REGISTERED))
  32 #define ASSERT_DPLL_PIN_REGISTERED(p) \
  33         WARN_ON_ONCE(!xa_get_mark(&dpll_pin_xa, (p)->id, DPLL_REGISTERED))
  34
  35 struct dpll_device_registration {
  36         struct list_head list;
  37         const struct dpll_device_ops *ops;
  38         void *priv;
  39 };
  40
  41 struct dpll_pin_registration {
  42         struct list_head list;
  43         const struct dpll_pin_ops *ops;
  44         void *priv;
  45         void *cookie;
  46 };
  47
  48 struct dpll_device *dpll_device_get_by_id(int id)
  49 {
  50         if (xa_get_mark(&dpll_device_xa, id, DPLL_REGISTERED))
  51                 return xa_load(&dpll_device_xa, id);
  52
  53         return NULL;
  54 }
  55
  56 static struct dpll_pin_registration *
  57 dpll_pin_registration_find(struct dpll_pin_ref *ref,
  58                            const struct dpll_pin_ops *ops, void *priv,
  59                            void *cookie)
  60 {
  61         struct dpll_pin_registration *reg;
  62
  63         list_for_each_entry(reg, &ref->registration_list, list) {
  64                 if (reg->ops == ops && reg->priv == priv &&
  65                     reg->cookie == cookie)
  66                         return reg;
  67         }
  68         return NULL;
  69 }
  70
  71 static int
  72 dpll_xa_ref_pin_add(struct xarray *xa_pins, struct dpll_pin *pin,
  73                     const struct dpll_pin_ops *ops, void *priv,
  74                     void *cookie)
  75 {
  76         struct dpll_pin_registration *reg;
  77         struct dpll_pin_ref *ref;
  78         bool ref_exists = false;
  79         unsigned long i;
  80         int ret;
  81
  82         xa_for_each(xa_pins, i, ref) {
  83                 if (ref->pin != pin)
  84                         continue;
  85                 reg = dpll_pin_registration_find(ref, ops, priv, cookie);
  86                 if (reg) {
  87                         refcount_inc(&ref->refcount);
  88                         return 0;
  89                 }
  90                 ref_exists = true;
  91                 break;
  92         }
  93
  94         if (!ref_exists) {
  95                 ref = kzalloc(sizeof(*ref), GFP_KERNEL);
  96                 if (!ref)
  97                         return -ENOMEM;
  98                 ref->pin = pin;
  99                 INIT_LIST_HEAD(&ref->registration_list);
 100                 ret = xa_insert(xa_pins, pin->pin_idx, ref, GFP_KERNEL);
 101                 if (ret) {
 102                         kfree(ref);
 103                         return ret;
 104                 }
 105                 refcount_set(&ref->refcount, 1);
 106         }
 107
 108         reg = kzalloc(sizeof(*reg), GFP_KERNEL);
 109         if (!reg) {
 110                 if (!ref_exists) {
 111                         xa_erase(xa_pins, pin->pin_idx);
 112                         kfree(ref);
 113                 }
 114                 return -ENOMEM;
 115         }
 116         reg->ops = ops;
 117         reg->priv = priv;
 118         reg->cookie = cookie;
 119         if (ref_exists)
 120                 refcount_inc(&ref->refcount);
 121         list_add_tail(&reg->list, &ref->registration_list);
 122
 123         return 0;
 124 }
 125
 126 static int dpll_xa_ref_pin_del(struct xarray *xa_pins, struct dpll_pin *pin,
 127                                const struct dpll_pin_ops *ops, void *priv,
 128                                void *cookie)
 129 {
 130         struct dpll_pin_registration *reg;
 131         struct dpll_pin_ref *ref;
 132         unsigned long i;
 133
 134         xa_for_each(xa_pins, i, ref) {
 135                 if (ref->pin != pin)
 136                         continue;
 137                 reg = dpll_pin_registration_find(ref, ops, priv, cookie);
 138                 if (WARN_ON(!reg))
 139                         return -EINVAL;
 140                 list_del(&reg->list);
 141                 kfree(reg);
 142                 if (refcount_dec_and_test(&ref->refcount)) {
 143                         xa_erase(xa_pins, i);
 144                         WARN_ON(!list_empty(&ref->registration_list));
 145                         kfree(ref);
 146                 }
 147                 return 0;
 148         }
 149
 150         return -EINVAL;
 151 }
 152
 153 static int
 154 dpll_xa_ref_dpll_add(struct xarray *xa_dplls, struct dpll_device *dpll,
 155                      const struct dpll_pin_ops *ops, void *priv, void *cookie)
 156 {
 157         struct dpll_pin_registration *reg;
 158         struct dpll_pin_ref *ref;
 159         bool ref_exists = false;
 160         unsigned long i;
 161         int ret;
 162
 163         xa_for_each(xa_dplls, i, ref) {
 164                 if (ref->dpll != dpll)
 165                         continue;
 166                 reg = dpll_pin_registration_find(ref, ops, priv, cookie);
 167                 if (reg) {
 168                         refcount_inc(&ref->refcount);
 169                         return 0;
 170                 }
 171                 ref_exists = true;
 172                 break;
 173         }
 174
 175         if (!ref_exists) {
 176                 ref = kzalloc(sizeof(*ref), GFP_KERNEL);
 177                 if (!ref)
 178                         return -ENOMEM;
 179                 ref->dpll = dpll;
 180                 INIT_LIST_HEAD(&ref->registration_list);
 181                 ret = xa_insert(xa_dplls, dpll->id, ref, GFP_KERNEL);
 182                 if (ret) {
 183                         kfree(ref);
 184                         return ret;
 185                 }
 186                 refcount_set(&ref->refcount, 1);
 187         }
 188
 189         reg = kzalloc(sizeof(*reg), GFP_KERNEL);
 190         if (!reg) {
 191                 if (!ref_exists) {
 192                         xa_erase(xa_dplls, dpll->id);
 193                         kfree(ref);
 194                 }
 195                 return -ENOMEM;
 196         }
 197         reg->ops = ops;
 198         reg->priv = priv;
 199         reg->cookie = cookie;
 200         if (ref_exists)
 201                 refcount_inc(&ref->refcount);
 202         list_add_tail(&reg->list, &ref->registration_list);
 203
 204         return 0;
 205 }
 206
 207 static void
 208 dpll_xa_ref_dpll_del(struct xarray *xa_dplls, struct dpll_device *dpll,
 209                      const struct dpll_pin_ops *ops, void *priv, void *cookie)
 210 {
 211         struct dpll_pin_registration *reg;
 212         struct dpll_pin_ref *ref;
 213         unsigned long i;
 214
 215         xa_for_each(xa_dplls, i, ref) {
 216                 if (ref->dpll != dpll)
 217                         continue;
 218                 reg = dpll_pin_registration_find(ref, ops, priv, cookie);
 219                 if (WARN_ON(!reg))
 220                         return;
 221                 list_del(&reg->list);
 222                 kfree(reg);
 223                 if (refcount_dec_and_test(&ref->refcount)) {
 224                         xa_erase(xa_dplls, i);
 225                         WARN_ON(!list_empty(&ref->registration_list));
 226                         kfree(ref);
 227                 }
 228                 return;
 229         }
 230 }
 231
 232 struct dpll_pin_ref *dpll_xa_ref_dpll_first(struct xarray *xa_refs)
 233 {
 234         struct dpll_pin_ref *ref;
 235         unsigned long i = 0;
 236
 237         ref = xa_find(xa_refs, &i, ULONG_MAX, XA_PRESENT);
 238         WARN_ON(!ref);
 239         return ref;
 240 }
 241
 242 static struct dpll_device *
 243 dpll_device_alloc(const u64 clock_id, u32 device_idx, struct module *module)
 244 {
 245         struct dpll_device *dpll;
 246         int ret;
 247
 248         dpll = kzalloc(sizeof(*dpll), GFP_KERNEL);
 249         if (!dpll)
 250                 return ERR_PTR(-ENOMEM);
 251         refcount_set(&dpll->refcount, 1);
 252         INIT_LIST_HEAD(&dpll->registration_list);
 253         dpll->device_idx = device_idx;
 254         dpll->clock_id = clock_id;
 255         dpll->module = module;
 256         ret = xa_alloc_cyclic(&dpll_device_xa, &dpll->id, dpll, xa_limit_32b,
 257                               &dpll_device_xa_id, GFP_KERNEL);
 258         if (ret < 0) {
 259                 kfree(dpll);
 260                 return ERR_PTR(ret);
 261         }
 262         xa_init_flags(&dpll->pin_refs, XA_FLAGS_ALLOC);
 263
 264         return dpll;
 265 }
 266
 267 /**
 268  * dpll_device_get - find existing or create new dpll device
 269  * @clock_id: clock_id of creator
 270  * @device_idx: idx given by device driver
 271  * @module: reference to registering module
 272  *
 273  * Get existing object of a dpll device, unique for given arguments.
 274  * Create new if doesn't exist yet.
 275  *
 276  * Context: Acquires a lock (dpll_lock)
 277  * Return:
 278  * * valid dpll_device struct pointer if succeeded
 279  * * ERR_PTR(X) - error
 280  */
 281 struct dpll_device *
 282 dpll_device_get(u64 clock_id, u32 device_idx, struct module *module)
 283 {
 284         struct dpll_device *dpll, *ret = NULL;
 285         unsigned long index;
 286
 287         mutex_lock(&dpll_lock);
 288         xa_for_each(&dpll_device_xa, index, dpll) {
 289                 if (dpll->clock_id == clock_id &&
 290                     dpll->device_idx == device_idx &&
 291                     dpll->module == module) {
 292                         ret = dpll;
 293                         refcount_inc(&ret->refcount);
 294                         break;
 295                 }
 296         }
 297         if (!ret)
 298                 ret = dpll_device_alloc(clock_id, device_idx, module);
 299         mutex_unlock(&dpll_lock);
 300
 301         return ret;
 302 }
 303 EXPORT_SYMBOL_GPL(dpll_device_get);
 304
 305 /**
 306  * dpll_device_put - decrease the refcount and free memory if possible
 307  * @dpll: dpll_device struct pointer
 308  *
 309  * Context: Acquires a lock (dpll_lock)
 310  * Drop reference for a dpll device, if all references are gone, delete
 311  * dpll device object.
 312  */
 313 void dpll_device_put(struct dpll_device *dpll)
 314 {
 315         mutex_lock(&dpll_lock);
 316         if (refcount_dec_and_test(&dpll->refcount)) {
 317                 ASSERT_DPLL_NOT_REGISTERED(dpll);
 318                 WARN_ON_ONCE(!xa_empty(&dpll->pin_refs));
 319                 xa_destroy(&dpll->pin_refs);
 320                 xa_erase(&dpll_device_xa, dpll->id);
 321                 WARN_ON(!list_empty(&dpll->registration_list));
 322                 kfree(dpll);
 323         }
 324         mutex_unlock(&dpll_lock);
 325 }
 326 EXPORT_SYMBOL_GPL(dpll_device_put);
 327
 328 static struct dpll_device_registration *
 329 dpll_device_registration_find(struct dpll_device *dpll,
 330                               const struct dpll_device_ops *ops, void *priv)
 331 {
 332         struct dpll_device_registration *reg;
 333
 334         list_for_each_entry(reg, &dpll->registration_list, list) {
 335                 if (reg->ops == ops && reg->priv == priv)
 336                         return reg;
 337         }
 338         return NULL;
 339 }
 340
 341 /**
 342  * dpll_device_register - register the dpll device in the subsystem
 343  * @dpll: pointer to a dpll
 344  * @type: type of a dpll
 345  * @ops: ops for a dpll device
 346  * @priv: pointer to private information of owner
 347  *
 348  * Make dpll device available for user space.
 349  *
 350  * Context: Acquires a lock (dpll_lock)
 351  * Return:
 352  * * 0 on success
 353  * * negative - error value
 354  */
 355 int dpll_device_register(struct dpll_device *dpll, enum dpll_type type,
 356                          const struct dpll_device_ops *ops, void *priv)
 357 {
 358         struct dpll_device_registration *reg;
 359         bool first_registration = false;
 360
 361         if (WARN_ON(!ops))
 362                 return -EINVAL;
 363         if (WARN_ON(!ops->mode_get))
 364                 return -EINVAL;
 365         if (WARN_ON(!ops->lock_status_get))
 366                 return -EINVAL;
 367         if (WARN_ON(type < DPLL_TYPE_PPS || type > DPLL_TYPE_MAX))
 368                 return -EINVAL;
 369
 370         mutex_lock(&dpll_lock);
 371         reg = dpll_device_registration_find(dpll, ops, priv);
 372         if (reg) {
 373                 mutex_unlock(&dpll_lock);
 374                 return -EEXIST;
 375         }
 376
 377         reg = kzalloc(sizeof(*reg), GFP_KERNEL);
 378         if (!reg) {
 379                 mutex_unlock(&dpll_lock);
 380                 return -ENOMEM;
 381         }
 382         reg->ops = ops;
 383         reg->priv = priv;
 384         dpll->type = type;
 385         first_registration = list_empty(&dpll->registration_list);
 386         list_add_tail(&reg->list, &dpll->registration_list);
 387         if (!first_registration) {
 388                 mutex_unlock(&dpll_lock);
 389                 return 0;
 390         }
 391
 392         xa_set_mark(&dpll_device_xa, dpll->id, DPLL_REGISTERED);
 393         dpll_device_create_ntf(dpll);
 394         mutex_unlock(&dpll_lock);
 395
 396         return 0;
 397 }
 398 EXPORT_SYMBOL_GPL(dpll_device_register);
 399
 400 /**
 401  * dpll_device_unregister - unregister dpll device
 402  * @dpll: registered dpll pointer
 403  * @ops: ops for a dpll device
 404  * @priv: pointer to private information of owner
 405  *
 406  * Unregister device, make it unavailable for userspace.
 407  * Note: It does not free the memory
 408  * Context: Acquires a lock (dpll_lock)
 409  */
 410 void dpll_device_unregister(struct dpll_device *dpll,
 411                             const struct dpll_device_ops *ops, void *priv)
 412 {
 413         struct dpll_device_registration *reg;
 414
 415         mutex_lock(&dpll_lock);
 416         ASSERT_DPLL_REGISTERED(dpll);
 417         dpll_device_delete_ntf(dpll);
 418         reg = dpll_device_registration_find(dpll, ops, priv);
 419         if (WARN_ON(!reg)) {
 420                 mutex_unlock(&dpll_lock);
 421                 return;
 422         }
 423         list_del(&reg->list);
 424         kfree(reg);
 425
 426         if (!list_empty(&dpll->registration_list)) {
 427                 mutex_unlock(&dpll_lock);
 428                 return;
 429         }
 430         xa_clear_mark(&dpll_device_xa, dpll->id, DPLL_REGISTERED);
 431         mutex_unlock(&dpll_lock);
 432 }
 433 EXPORT_SYMBOL_GPL(dpll_device_unregister);
 434
 435 static void dpll_pin_prop_free(struct dpll_pin_properties *prop)
 436 {
 437         kfree(prop->package_label);
 438         kfree(prop->panel_label);
 439         kfree(prop->board_label);
 440         kfree(prop->freq_supported);
 441 }
 442
 443 static int dpll_pin_prop_dup(const struct dpll_pin_properties *src,
 444                              struct dpll_pin_properties *dst)
 445 {
 446         memcpy(dst, src, sizeof(*dst));
 447         if (src->freq_supported && src->freq_supported_num) {
 448                 size_t freq_size = src->freq_supported_num *
 449                                    sizeof(*src->freq_supported);
 450                 dst->freq_supported = kmemdup(src->freq_supported,
 451                                               freq_size, GFP_KERNEL);
 452                 if (!dst->freq_supported)
 453                         return -ENOMEM;
 454         }
 455         if (src->board_label) {
 456                 dst->board_label = kstrdup(src->board_label, GFP_KERNEL);
 457                 if (!dst->board_label)
 458                         goto err_board_label;
 459         }
 460         if (src->panel_label) {
 461                 dst->panel_label = kstrdup(src->panel_label, GFP_KERNEL);
 462                 if (!dst->panel_label)
 463                         goto err_panel_label;
 464         }
 465         if (src->package_label) {
 466                 dst->package_label = kstrdup(src->package_label, GFP_KERNEL);
 467                 if (!dst->package_label)
 468                         goto err_package_label;
 469         }
 470
 471         return 0;
 472
 473 err_package_label:
 474         kfree(dst->panel_label);
 475 err_panel_label:
 476         kfree(dst->board_label);
 477 err_board_label:
 478         kfree(dst->freq_supported);
 479         return -ENOMEM;
 480 }
 481
 482 static struct dpll_pin *
 483 dpll_pin_alloc(u64 clock_id, u32 pin_idx, struct module *module,
 484                const struct dpll_pin_properties *prop)
 485 {
 486         struct dpll_pin *pin;
 487         int ret;
 488
 489         pin = kzalloc(sizeof(*pin), GFP_KERNEL);
 490         if (!pin)
 491                 return ERR_PTR(-ENOMEM);
 492         pin->pin_idx = pin_idx;
 493         pin->clock_id = clock_id;
 494         pin->module = module;
 495         if (WARN_ON(prop->type < DPLL_PIN_TYPE_MUX ||
 496                     prop->type > DPLL_PIN_TYPE_MAX)) {
 497                 ret = -EINVAL;
 498                 goto err_pin_prop;
 499         }
 500         ret = dpll_pin_prop_dup(prop, &pin->prop);
 501         if (ret)
 502                 goto err_pin_prop;
 503         refcount_set(&pin->refcount, 1);
 504         xa_init_flags(&pin->dpll_refs, XA_FLAGS_ALLOC);
 505         xa_init_flags(&pin->parent_refs, XA_FLAGS_ALLOC);
 506         ret = xa_alloc_cyclic(&dpll_pin_xa, &pin->id, pin, xa_limit_32b,
 507                               &dpll_pin_xa_id, GFP_KERNEL);
 508         if (ret)
 509                 goto err_xa_alloc;
 510         return pin;
 511 err_xa_alloc:
 512         xa_destroy(&pin->dpll_refs);
 513         xa_destroy(&pin->parent_refs);
 514         dpll_pin_prop_free(&pin->prop);
 515 err_pin_prop:
 516         kfree(pin);
 517         return ERR_PTR(ret);
 518 }
 519
 520 static void dpll_netdev_pin_assign(struct net_device *dev, struct dpll_pin *dpll_pin)
 521 {
 522         rtnl_lock();
 523         rcu_assign_pointer(dev->dpll_pin, dpll_pin);
 524         rtnl_unlock();
 525 }
 526
 527 void dpll_netdev_pin_set(struct net_device *dev, struct dpll_pin *dpll_pin)
 528 {
 529         WARN_ON(!dpll_pin);
 530         dpll_netdev_pin_assign(dev, dpll_pin);
 531 }
 532 EXPORT_SYMBOL(dpll_netdev_pin_set);
 533
 534 void dpll_netdev_pin_clear(struct net_device *dev)
 535 {
 536         dpll_netdev_pin_assign(dev, NULL);
 537 }
 538 EXPORT_SYMBOL(dpll_netdev_pin_clear);
 539
 540 /**
 541  * dpll_pin_get - find existing or create new dpll pin
 542  * @clock_id: clock_id of creator
 543  * @pin_idx: idx given by dev driver
 544  * @module: reference to registering module
 545  * @prop: dpll pin properties
 546  *
 547  * Get existing object of a pin (unique for given arguments) or create new
 548  * if doesn't exist yet.
 549  *
 550  * Context: Acquires a lock (dpll_lock)
 551  * Return:
 552  * * valid allocated dpll_pin struct pointer if succeeded
 553  * * ERR_PTR(X) - error
 554  */
 555 struct dpll_pin *
 556 dpll_pin_get(u64 clock_id, u32 pin_idx, struct module *module,
 557              const struct dpll_pin_properties *prop)
 558 {
 559         struct dpll_pin *pos, *ret = NULL;
 560         unsigned long i;
 561
 562         mutex_lock(&dpll_lock);
 563         xa_for_each(&dpll_pin_xa, i, pos) {
 564                 if (pos->clock_id == clock_id &&
 565                     pos->pin_idx == pin_idx &&
 566                     pos->module == module) {
 567                         ret = pos;
 568                         refcount_inc(&ret->refcount);
 569                         break;
 570                 }
 571         }
 572         if (!ret)
 573                 ret = dpll_pin_alloc(clock_id, pin_idx, module, prop);
 574         mutex_unlock(&dpll_lock);
 575
 576         return ret;
 577 }
 578 EXPORT_SYMBOL_GPL(dpll_pin_get);
 579
 580 /**
 581  * dpll_pin_put - decrease the refcount and free memory if possible
 582  * @pin: pointer to a pin to be put
 583  *
 584  * Drop reference for a pin, if all references are gone, delete pin object.
 585  *
 586  * Context: Acquires a lock (dpll_lock)
 587  */
 588 void dpll_pin_put(struct dpll_pin *pin)
 589 {
 590         mutex_lock(&dpll_lock);
 591         if (refcount_dec_and_test(&pin->refcount)) {
 592                 xa_erase(&dpll_pin_xa, pin->id);
 593                 xa_destroy(&pin->dpll_refs);
 594                 xa_destroy(&pin->parent_refs);
 595                 dpll_pin_prop_free(&pin->prop);
 596                 kfree_rcu(pin, rcu);
 597         }
 598         mutex_unlock(&dpll_lock);
 599 }
 600 EXPORT_SYMBOL_GPL(dpll_pin_put);
 601
 602 static int
 603 __dpll_pin_register(struct dpll_device *dpll, struct dpll_pin *pin,
 604                     const struct dpll_pin_ops *ops, void *priv, void *cookie)
 605 {
 606         int ret;
 607
 608         ret = dpll_xa_ref_pin_add(&dpll->pin_refs, pin, ops, priv, cookie);
 609         if (ret)
 610                 return ret;
 611         ret = dpll_xa_ref_dpll_add(&pin->dpll_refs, dpll, ops, priv, cookie);
 612         if (ret)
 613                 goto ref_pin_del;
 614         xa_set_mark(&dpll_pin_xa, pin->id, DPLL_REGISTERED);
 615         dpll_pin_create_ntf(pin);
 616
 617         return ret;
 618
 619 ref_pin_del:
 620         dpll_xa_ref_pin_del(&dpll->pin_refs, pin, ops, priv, cookie);
 621         return ret;
 622 }
 623
 624 /**
 625  * dpll_pin_register - register the dpll pin in the subsystem
 626  * @dpll: pointer to a dpll
 627  * @pin: pointer to a dpll pin
 628  * @ops: ops for a dpll pin ops
 629  * @priv: pointer to private information of owner
 630  *
 631  * Context: Acquires a lock (dpll_lock)
 632  * Return:
 633  * * 0 on success
 634  * * negative - error value
 635  */
 636 int
 637 dpll_pin_register(struct dpll_device *dpll, struct dpll_pin *pin,
 638                   const struct dpll_pin_ops *ops, void *priv)
 639 {
 640         int ret;
 641
 642         if (WARN_ON(!ops) ||
 643             WARN_ON(!ops->state_on_dpll_get) ||
 644             WARN_ON(!ops->direction_get))
 645                 return -EINVAL;
 646
 647         mutex_lock(&dpll_lock);
 648         if (WARN_ON(!(dpll->module == pin->module &&
 649                       dpll->clock_id == pin->clock_id)))
 650                 ret = -EINVAL;
 651         else
 652                 ret = __dpll_pin_register(dpll, pin, ops, priv, NULL);
 653         mutex_unlock(&dpll_lock);
 654
 655         return ret;
 656 }
 657 EXPORT_SYMBOL_GPL(dpll_pin_register);
 658
 659 static void
 660 __dpll_pin_unregister(struct dpll_device *dpll, struct dpll_pin *pin,
 661                       const struct dpll_pin_ops *ops, void *priv, void *cookie)
 662 {
 663         ASSERT_DPLL_PIN_REGISTERED(pin);
 664         dpll_xa_ref_pin_del(&dpll->pin_refs, pin, ops, priv, cookie);
 665         dpll_xa_ref_dpll_del(&pin->dpll_refs, dpll, ops, priv, cookie);
 666         if (xa_empty(&pin->dpll_refs))
 667                 xa_clear_mark(&dpll_pin_xa, pin->id, DPLL_REGISTERED);
 668 }
 669
 670 /**
 671  * dpll_pin_unregister - unregister dpll pin from dpll device
 672  * @dpll: registered dpll pointer
 673  * @pin: pointer to a pin
 674  * @ops: ops for a dpll pin
 675  * @priv: pointer to private information of owner
 676  *
 677  * Note: It does not free the memory
 678  * Context: Acquires a lock (dpll_lock)
 679  */
 680 void dpll_pin_unregister(struct dpll_device *dpll, struct dpll_pin *pin,
 681                          const struct dpll_pin_ops *ops, void *priv)
 682 {
 683         if (WARN_ON(xa_empty(&dpll->pin_refs)))
 684                 return;
 685         if (WARN_ON(!xa_empty(&pin->parent_refs)))
 686                 return;
 687
 688         mutex_lock(&dpll_lock);
 689         dpll_pin_delete_ntf(pin);
 690         __dpll_pin_unregister(dpll, pin, ops, priv, NULL);
 691         mutex_unlock(&dpll_lock);
 692 }
 693 EXPORT_SYMBOL_GPL(dpll_pin_unregister);
 694
 695 /**
 696  * dpll_pin_on_pin_register - register a pin with a parent pin
 697  * @parent: pointer to a parent pin
 698  * @pin: pointer to a pin
 699  * @ops: ops for a dpll pin
 700  * @priv: pointer to private information of owner
 701  *
 702  * Register a pin with a parent pin, create references between them and
 703  * between newly registered pin and dplls connected with a parent pin.
 704  *
 705  * Context: Acquires a lock (dpll_lock)
 706  * Return:
 707  * * 0 on success
 708  * * negative - error value
 709  */
 710 int dpll_pin_on_pin_register(struct dpll_pin *parent, struct dpll_pin *pin,
 711                              const struct dpll_pin_ops *ops, void *priv)
 712 {
 713         struct dpll_pin_ref *ref;
 714         unsigned long i, stop;
 715         int ret;
 716
 717         if (WARN_ON(parent->prop.type != DPLL_PIN_TYPE_MUX))
 718                 return -EINVAL;
 719
 720         if (WARN_ON(!ops) ||
 721             WARN_ON(!ops->state_on_pin_get) ||
 722             WARN_ON(!ops->direction_get))
 723                 return -EINVAL;
 724
 725         mutex_lock(&dpll_lock);
 726         ret = dpll_xa_ref_pin_add(&pin->parent_refs, parent, ops, priv, pin);
 727         if (ret)
 728                 goto unlock;
 729         refcount_inc(&pin->refcount);
 730         xa_for_each(&parent->dpll_refs, i, ref) {
 731                 ret = __dpll_pin_register(ref->dpll, pin, ops, priv, parent);
 732                 if (ret) {
 733                         stop = i;
 734                         goto dpll_unregister;
 735                 }
 736                 dpll_pin_create_ntf(pin);
 737         }
 738         mutex_unlock(&dpll_lock);
 739
 740         return ret;
 741
 742 dpll_unregister:
 743         xa_for_each(&parent->dpll_refs, i, ref)
 744                 if (i < stop) {
 745                         __dpll_pin_unregister(ref->dpll, pin, ops, priv,
 746                                               parent);
 747                         dpll_pin_delete_ntf(pin);
 748                 }
 749         refcount_dec(&pin->refcount);
 750         dpll_xa_ref_pin_del(&pin->parent_refs, parent, ops, priv, pin);
 751 unlock:
 752         mutex_unlock(&dpll_lock);
 753         return ret;
 754 }
 755 EXPORT_SYMBOL_GPL(dpll_pin_on_pin_register);
 756
 757 /**
 758  * dpll_pin_on_pin_unregister - unregister dpll pin from a parent pin
 759  * @parent: pointer to a parent pin
 760  * @pin: pointer to a pin
 761  * @ops: ops for a dpll pin
 762  * @priv: pointer to private information of owner
 763  *
 764  * Context: Acquires a lock (dpll_lock)
 765  * Note: It does not free the memory
 766  */
 767 void dpll_pin_on_pin_unregister(struct dpll_pin *parent, struct dpll_pin *pin,
 768                                 const struct dpll_pin_ops *ops, void *priv)
 769 {
 770         struct dpll_pin_ref *ref;
 771         unsigned long i;
 772
 773         mutex_lock(&dpll_lock);
 774         dpll_pin_delete_ntf(pin);
 775         dpll_xa_ref_pin_del(&pin->parent_refs, parent, ops, priv, pin);
 776         refcount_dec(&pin->refcount);
 777         xa_for_each(&pin->dpll_refs, i, ref)
 778                 __dpll_pin_unregister(ref->dpll, pin, ops, priv, parent);
 779         mutex_unlock(&dpll_lock);
 780 }
 781 EXPORT_SYMBOL_GPL(dpll_pin_on_pin_unregister);
 782
 783 static struct dpll_device_registration *
 784 dpll_device_registration_first(struct dpll_device *dpll)
 785 {
 786         struct dpll_device_registration *reg;
 787
 788         reg = list_first_entry_or_null((struct list_head *)&dpll->registration_list,
 789                                        struct dpll_device_registration, list);
 790         WARN_ON(!reg);
 791         return reg;
 792 }
 793
 794 void *dpll_priv(struct dpll_device *dpll)
 795 {
 796         struct dpll_device_registration *reg;
 797
 798         reg = dpll_device_registration_first(dpll);
 799         return reg->priv;
 800 }
 801
 802 const struct dpll_device_ops *dpll_device_ops(struct dpll_device *dpll)
 803 {
 804         struct dpll_device_registration *reg;
 805
 806         reg = dpll_device_registration_first(dpll);
 807         return reg->ops;
 808 }
 809
 810 static struct dpll_pin_registration *
 811 dpll_pin_registration_first(struct dpll_pin_ref *ref)
 812 {
 813         struct dpll_pin_registration *reg;
 814
 815         reg = list_first_entry_or_null(&ref->registration_list,
 816                                        struct dpll_pin_registration, list);
 817         WARN_ON(!reg);
 818         return reg;
 819 }
 820
 821 void *dpll_pin_on_dpll_priv(struct dpll_device *dpll,
 822                             struct dpll_pin *pin)
 823 {
 824         struct dpll_pin_registration *reg;
 825         struct dpll_pin_ref *ref;
 826
 827         ref = xa_load(&dpll->pin_refs, pin->pin_idx);
 828         if (!ref)
 829                 return NULL;
 830         reg = dpll_pin_registration_first(ref);
 831         return reg->priv;
 832 }
 833
 834 void *dpll_pin_on_pin_priv(struct dpll_pin *parent,
 835                            struct dpll_pin *pin)
 836 {
 837         struct dpll_pin_registration *reg;
 838         struct dpll_pin_ref *ref;
 839
 840         ref = xa_load(&pin->parent_refs, parent->pin_idx);
 841         if (!ref)
 842                 return NULL;
 843         reg = dpll_pin_registration_first(ref);
 844         return reg->priv;
 845 }
 846
 847 const struct dpll_pin_ops *dpll_pin_ops(struct dpll_pin_ref *ref)
 848 {
 849         struct dpll_pin_registration *reg;
 850
 851         reg = dpll_pin_registration_first(ref);
 852         return reg->ops;
 853 }
 854
 855 static int __init dpll_init(void)
 856 {
 857         int ret;
 858
 859         ret = genl_register_family(&dpll_nl_family);
 860         if (ret)
 861                 goto error;
 862
 863         return 0;
 864
 865 error:
 866         mutex_destroy(&dpll_lock);
 867         return ret;
 868 }
 869
 870 static void __exit dpll_exit(void)
 871 {
 872         genl_unregister_family(&dpll_nl_family);
 873         mutex_destroy(&dpll_lock);
 874 }
 875
 876 subsys_initcall(dpll_init);
 877 module_exit(dpll_exit);