1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * PCI Endpoint *Controller* (EPC) library 4 * 5 * Copyright (C) 2017 Texas Instruments 6 * Author: Kishon Vijay Abraham I <kishon@ti.com> 7 */ 8 9 #include <linux/device.h> 10 #include <linux/slab.h> 11 #include <linux/module.h> 12 #include <linux/of_device.h> 13 14 #include <linux/pci-epc.h> 15 #include <linux/pci-epf.h> 16 #include <linux/pci-ep-cfs.h> 17 18 static struct class *pci_epc_class; 19 20 static void devm_pci_epc_release(struct device *dev, void *res) 21 { 22 struct pci_epc *epc = *(struct pci_epc **)res; 23 24 pci_epc_destroy(epc); 25 } 26 27 static int devm_pci_epc_match(struct device *dev, void *res, void *match_data) 28 { 29 struct pci_epc **epc = res; 30 31 return *epc == match_data; 32 } 33 34 /** 35 * pci_epc_put() - release the PCI endpoint controller 36 * @epc: epc returned by pci_epc_get() 37 * 38 * release the refcount the caller obtained by invoking pci_epc_get() 39 */ 40 void pci_epc_put(struct pci_epc *epc) 41 { 42 if (!epc || IS_ERR(epc)) 43 return; 44 45 module_put(epc->ops->owner); 46 put_device(&epc->dev); 47 } 48 EXPORT_SYMBOL_GPL(pci_epc_put); 49 50 /** 51 * pci_epc_get() - get the PCI endpoint controller 52 * @epc_name: device name of the endpoint controller 53 * 54 * Invoke to get struct pci_epc * corresponding to the device name of the 55 * endpoint controller 56 */ 57 struct pci_epc *pci_epc_get(const char *epc_name) 58 { 59 int ret = -EINVAL; 60 struct pci_epc *epc; 61 struct device *dev; 62 struct class_dev_iter iter; 63 64 class_dev_iter_init(&iter, pci_epc_class, NULL, NULL); 65 while ((dev = class_dev_iter_next(&iter))) { 66 if (strcmp(epc_name, dev_name(dev))) 67 continue; 68 69 epc = to_pci_epc(dev); 70 if (!try_module_get(epc->ops->owner)) { 71 ret = -EINVAL; 72 goto err; 73 } 74 75 class_dev_iter_exit(&iter); 76 get_device(&epc->dev); 77 return epc; 78 } 79 80 err: 81 class_dev_iter_exit(&iter); 82 return ERR_PTR(ret); 83 } 84 EXPORT_SYMBOL_GPL(pci_epc_get); 85 86 /** 87 * pci_epc_get_first_free_bar() - helper to get first unreserved BAR 88 * @epc_features: pci_epc_features structure that holds the reserved bar bitmap 89 * 90 * Invoke to get the first unreserved BAR that can be used by the endpoint 91 * function. For any incorrect value in reserved_bar return '0'. 92 */ 93 enum pci_barno 94 pci_epc_get_first_free_bar(const struct pci_epc_features *epc_features) 95 { 96 return pci_epc_get_next_free_bar(epc_features, BAR_0); 97 } 98 EXPORT_SYMBOL_GPL(pci_epc_get_first_free_bar); 99 100 /** 101 * pci_epc_get_next_free_bar() - helper to get unreserved BAR starting from @bar 102 * @epc_features: pci_epc_features structure that holds the reserved bar bitmap 103 * @bar: the starting BAR number from where unreserved BAR should be searched 104 * 105 * Invoke to get the next unreserved BAR starting from @bar that can be used 106 * for endpoint function. For any incorrect value in reserved_bar return '0'. 107 */ 108 enum pci_barno pci_epc_get_next_free_bar(const struct pci_epc_features 109 *epc_features, enum pci_barno bar) 110 { 111 unsigned long free_bar; 112 113 if (!epc_features) 114 return BAR_0; 115 116 /* If 'bar - 1' is a 64-bit BAR, move to the next BAR */ 117 if ((epc_features->bar_fixed_64bit << 1) & 1 << bar) 118 bar++; 119 120 /* Find if the reserved BAR is also a 64-bit BAR */ 121 free_bar = epc_features->reserved_bar & epc_features->bar_fixed_64bit; 122 123 /* Set the adjacent bit if the reserved BAR is also a 64-bit BAR */ 124 free_bar <<= 1; 125 free_bar |= epc_features->reserved_bar; 126 127 free_bar = find_next_zero_bit(&free_bar, 6, bar); 128 if (free_bar > 5) 129 return NO_BAR; 130 131 return free_bar; 132 } 133 EXPORT_SYMBOL_GPL(pci_epc_get_next_free_bar); 134 135 /** 136 * pci_epc_get_features() - get the features supported by EPC 137 * @epc: the features supported by *this* EPC device will be returned 138 * @func_no: the features supported by the EPC device specific to the 139 * endpoint function with func_no will be returned 140 * 141 * Invoke to get the features provided by the EPC which may be 142 * specific to an endpoint function. Returns pci_epc_features on success 143 * and NULL for any failures. 144 */ 145 const struct pci_epc_features *pci_epc_get_features(struct pci_epc *epc, 146 u8 func_no) 147 { 148 const struct pci_epc_features *epc_features; 149 150 if (IS_ERR_OR_NULL(epc) || func_no >= epc->max_functions) 151 return NULL; 152 153 if (!epc->ops->get_features) 154 return NULL; 155 156 mutex_lock(&epc->lock); 157 epc_features = epc->ops->get_features(epc, func_no); 158 mutex_unlock(&epc->lock); 159 160 return epc_features; 161 } 162 EXPORT_SYMBOL_GPL(pci_epc_get_features); 163 164 /** 165 * pci_epc_stop() - stop the PCI link 166 * @epc: the link of the EPC device that has to be stopped 167 * 168 * Invoke to stop the PCI link 169 */ 170 void pci_epc_stop(struct pci_epc *epc) 171 { 172 if (IS_ERR(epc) || !epc->ops->stop) 173 return; 174 175 mutex_lock(&epc->lock); 176 epc->ops->stop(epc); 177 mutex_unlock(&epc->lock); 178 } 179 EXPORT_SYMBOL_GPL(pci_epc_stop); 180 181 /** 182 * pci_epc_start() - start the PCI link 183 * @epc: the link of *this* EPC device has to be started 184 * 185 * Invoke to start the PCI link 186 */ 187 int pci_epc_start(struct pci_epc *epc) 188 { 189 int ret; 190 191 if (IS_ERR(epc)) 192 return -EINVAL; 193 194 if (!epc->ops->start) 195 return 0; 196 197 mutex_lock(&epc->lock); 198 ret = epc->ops->start(epc); 199 mutex_unlock(&epc->lock); 200 201 return ret; 202 } 203 EXPORT_SYMBOL_GPL(pci_epc_start); 204 205 /** 206 * pci_epc_raise_irq() - interrupt the host system 207 * @epc: the EPC device which has to interrupt the host 208 * @func_no: the endpoint function number in the EPC device 209 * @type: specify the type of interrupt; legacy, MSI or MSI-X 210 * @interrupt_num: the MSI or MSI-X interrupt number 211 * 212 * Invoke to raise an legacy, MSI or MSI-X interrupt 213 */ 214 int pci_epc_raise_irq(struct pci_epc *epc, u8 func_no, 215 enum pci_epc_irq_type type, u16 interrupt_num) 216 { 217 int ret; 218 219 if (IS_ERR_OR_NULL(epc) || func_no >= epc->max_functions) 220 return -EINVAL; 221 222 if (!epc->ops->raise_irq) 223 return 0; 224 225 mutex_lock(&epc->lock); 226 ret = epc->ops->raise_irq(epc, func_no, type, interrupt_num); 227 mutex_unlock(&epc->lock); 228 229 return ret; 230 } 231 EXPORT_SYMBOL_GPL(pci_epc_raise_irq); 232 233 /** 234 * pci_epc_get_msi() - get the number of MSI interrupt numbers allocated 235 * @epc: the EPC device to which MSI interrupts was requested 236 * @func_no: the endpoint function number in the EPC device 237 * 238 * Invoke to get the number of MSI interrupts allocated by the RC 239 */ 240 int pci_epc_get_msi(struct pci_epc *epc, u8 func_no) 241 { 242 int interrupt; 243 244 if (IS_ERR_OR_NULL(epc) || func_no >= epc->max_functions) 245 return 0; 246 247 if (!epc->ops->get_msi) 248 return 0; 249 250 mutex_lock(&epc->lock); 251 interrupt = epc->ops->get_msi(epc, func_no); 252 mutex_unlock(&epc->lock); 253 254 if (interrupt < 0) 255 return 0; 256 257 interrupt = 1 << interrupt; 258 259 return interrupt; 260 } 261 EXPORT_SYMBOL_GPL(pci_epc_get_msi); 262 263 /** 264 * pci_epc_set_msi() - set the number of MSI interrupt numbers required 265 * @epc: the EPC device on which MSI has to be configured 266 * @func_no: the endpoint function number in the EPC device 267 * @interrupts: number of MSI interrupts required by the EPF 268 * 269 * Invoke to set the required number of MSI interrupts. 270 */ 271 int pci_epc_set_msi(struct pci_epc *epc, u8 func_no, u8 interrupts) 272 { 273 int ret; 274 u8 encode_int; 275 276 if (IS_ERR_OR_NULL(epc) || func_no >= epc->max_functions || 277 interrupts > 32) 278 return -EINVAL; 279 280 if (!epc->ops->set_msi) 281 return 0; 282 283 encode_int = order_base_2(interrupts); 284 285 mutex_lock(&epc->lock); 286 ret = epc->ops->set_msi(epc, func_no, encode_int); 287 mutex_unlock(&epc->lock); 288 289 return ret; 290 } 291 EXPORT_SYMBOL_GPL(pci_epc_set_msi); 292 293 /** 294 * pci_epc_get_msix() - get the number of MSI-X interrupt numbers allocated 295 * @epc: the EPC device to which MSI-X interrupts was requested 296 * @func_no: the endpoint function number in the EPC device 297 * 298 * Invoke to get the number of MSI-X interrupts allocated by the RC 299 */ 300 int pci_epc_get_msix(struct pci_epc *epc, u8 func_no) 301 { 302 int interrupt; 303 304 if (IS_ERR_OR_NULL(epc) || func_no >= epc->max_functions) 305 return 0; 306 307 if (!epc->ops->get_msix) 308 return 0; 309 310 mutex_lock(&epc->lock); 311 interrupt = epc->ops->get_msix(epc, func_no); 312 mutex_unlock(&epc->lock); 313 314 if (interrupt < 0) 315 return 0; 316 317 return interrupt + 1; 318 } 319 EXPORT_SYMBOL_GPL(pci_epc_get_msix); 320 321 /** 322 * pci_epc_set_msix() - set the number of MSI-X interrupt numbers required 323 * @epc: the EPC device on which MSI-X has to be configured 324 * @func_no: the endpoint function number in the EPC device 325 * @interrupts: number of MSI-X interrupts required by the EPF 326 * @bir: BAR where the MSI-X table resides 327 * @offset: Offset pointing to the start of MSI-X table 328 * 329 * Invoke to set the required number of MSI-X interrupts. 330 */ 331 int pci_epc_set_msix(struct pci_epc *epc, u8 func_no, u16 interrupts, 332 enum pci_barno bir, u32 offset) 333 { 334 int ret; 335 336 if (IS_ERR_OR_NULL(epc) || func_no >= epc->max_functions || 337 interrupts < 1 || interrupts > 2048) 338 return -EINVAL; 339 340 if (!epc->ops->set_msix) 341 return 0; 342 343 mutex_lock(&epc->lock); 344 ret = epc->ops->set_msix(epc, func_no, interrupts - 1, bir, offset); 345 mutex_unlock(&epc->lock); 346 347 return ret; 348 } 349 EXPORT_SYMBOL_GPL(pci_epc_set_msix); 350 351 /** 352 * pci_epc_unmap_addr() - unmap CPU address from PCI address 353 * @epc: the EPC device on which address is allocated 354 * @func_no: the endpoint function number in the EPC device 355 * @phys_addr: physical address of the local system 356 * 357 * Invoke to unmap the CPU address from PCI address. 358 */ 359 void pci_epc_unmap_addr(struct pci_epc *epc, u8 func_no, 360 phys_addr_t phys_addr) 361 { 362 if (IS_ERR_OR_NULL(epc) || func_no >= epc->max_functions) 363 return; 364 365 if (!epc->ops->unmap_addr) 366 return; 367 368 mutex_lock(&epc->lock); 369 epc->ops->unmap_addr(epc, func_no, phys_addr); 370 mutex_unlock(&epc->lock); 371 } 372 EXPORT_SYMBOL_GPL(pci_epc_unmap_addr); 373 374 /** 375 * pci_epc_map_addr() - map CPU address to PCI address 376 * @epc: the EPC device on which address is allocated 377 * @func_no: the endpoint function number in the EPC device 378 * @phys_addr: physical address of the local system 379 * @pci_addr: PCI address to which the physical address should be mapped 380 * @size: the size of the allocation 381 * 382 * Invoke to map CPU address with PCI address. 383 */ 384 int pci_epc_map_addr(struct pci_epc *epc, u8 func_no, 385 phys_addr_t phys_addr, u64 pci_addr, size_t size) 386 { 387 int ret; 388 389 if (IS_ERR_OR_NULL(epc) || func_no >= epc->max_functions) 390 return -EINVAL; 391 392 if (!epc->ops->map_addr) 393 return 0; 394 395 mutex_lock(&epc->lock); 396 ret = epc->ops->map_addr(epc, func_no, phys_addr, pci_addr, size); 397 mutex_unlock(&epc->lock); 398 399 return ret; 400 } 401 EXPORT_SYMBOL_GPL(pci_epc_map_addr); 402 403 /** 404 * pci_epc_clear_bar() - reset the BAR 405 * @epc: the EPC device for which the BAR has to be cleared 406 * @func_no: the endpoint function number in the EPC device 407 * @epf_bar: the struct epf_bar that contains the BAR information 408 * 409 * Invoke to reset the BAR of the endpoint device. 410 */ 411 void pci_epc_clear_bar(struct pci_epc *epc, u8 func_no, 412 struct pci_epf_bar *epf_bar) 413 { 414 if (IS_ERR_OR_NULL(epc) || func_no >= epc->max_functions || 415 (epf_bar->barno == BAR_5 && 416 epf_bar->flags & PCI_BASE_ADDRESS_MEM_TYPE_64)) 417 return; 418 419 if (!epc->ops->clear_bar) 420 return; 421 422 mutex_lock(&epc->lock); 423 epc->ops->clear_bar(epc, func_no, epf_bar); 424 mutex_unlock(&epc->lock); 425 } 426 EXPORT_SYMBOL_GPL(pci_epc_clear_bar); 427 428 /** 429 * pci_epc_set_bar() - configure BAR in order for host to assign PCI addr space 430 * @epc: the EPC device on which BAR has to be configured 431 * @func_no: the endpoint function number in the EPC device 432 * @epf_bar: the struct epf_bar that contains the BAR information 433 * 434 * Invoke to configure the BAR of the endpoint device. 435 */ 436 int pci_epc_set_bar(struct pci_epc *epc, u8 func_no, 437 struct pci_epf_bar *epf_bar) 438 { 439 int ret; 440 int flags = epf_bar->flags; 441 442 if (IS_ERR_OR_NULL(epc) || func_no >= epc->max_functions || 443 (epf_bar->barno == BAR_5 && 444 flags & PCI_BASE_ADDRESS_MEM_TYPE_64) || 445 (flags & PCI_BASE_ADDRESS_SPACE_IO && 446 flags & PCI_BASE_ADDRESS_IO_MASK) || 447 (upper_32_bits(epf_bar->size) && 448 !(flags & PCI_BASE_ADDRESS_MEM_TYPE_64))) 449 return -EINVAL; 450 451 if (!epc->ops->set_bar) 452 return 0; 453 454 mutex_lock(&epc->lock); 455 ret = epc->ops->set_bar(epc, func_no, epf_bar); 456 mutex_unlock(&epc->lock); 457 458 return ret; 459 } 460 EXPORT_SYMBOL_GPL(pci_epc_set_bar); 461 462 /** 463 * pci_epc_write_header() - write standard configuration header 464 * @epc: the EPC device to which the configuration header should be written 465 * @func_no: the endpoint function number in the EPC device 466 * @header: standard configuration header fields 467 * 468 * Invoke to write the configuration header to the endpoint controller. Every 469 * endpoint controller will have a dedicated location to which the standard 470 * configuration header would be written. The callback function should write 471 * the header fields to this dedicated location. 472 */ 473 int pci_epc_write_header(struct pci_epc *epc, u8 func_no, 474 struct pci_epf_header *header) 475 { 476 int ret; 477 478 if (IS_ERR_OR_NULL(epc) || func_no >= epc->max_functions) 479 return -EINVAL; 480 481 if (!epc->ops->write_header) 482 return 0; 483 484 mutex_lock(&epc->lock); 485 ret = epc->ops->write_header(epc, func_no, header); 486 mutex_unlock(&epc->lock); 487 488 return ret; 489 } 490 EXPORT_SYMBOL_GPL(pci_epc_write_header); 491 492 /** 493 * pci_epc_add_epf() - bind PCI endpoint function to an endpoint controller 494 * @epc: the EPC device to which the endpoint function should be added 495 * @epf: the endpoint function to be added 496 * 497 * A PCI endpoint device can have one or more functions. In the case of PCIe, 498 * the specification allows up to 8 PCIe endpoint functions. Invoke 499 * pci_epc_add_epf() to add a PCI endpoint function to an endpoint controller. 500 */ 501 int pci_epc_add_epf(struct pci_epc *epc, struct pci_epf *epf) 502 { 503 u32 func_no; 504 int ret = 0; 505 506 if (epf->epc) 507 return -EBUSY; 508 509 if (IS_ERR(epc)) 510 return -EINVAL; 511 512 mutex_lock(&epc->lock); 513 func_no = find_first_zero_bit(&epc->function_num_map, 514 BITS_PER_LONG); 515 if (func_no >= BITS_PER_LONG) { 516 ret = -EINVAL; 517 goto ret; 518 } 519 520 if (func_no > epc->max_functions - 1) { 521 dev_err(&epc->dev, "Exceeding max supported Function Number\n"); 522 ret = -EINVAL; 523 goto ret; 524 } 525 526 set_bit(func_no, &epc->function_num_map); 527 epf->func_no = func_no; 528 epf->epc = epc; 529 530 list_add_tail(&epf->list, &epc->pci_epf); 531 532 ret: 533 mutex_unlock(&epc->lock); 534 535 return ret; 536 } 537 EXPORT_SYMBOL_GPL(pci_epc_add_epf); 538 539 /** 540 * pci_epc_remove_epf() - remove PCI endpoint function from endpoint controller 541 * @epc: the EPC device from which the endpoint function should be removed 542 * @epf: the endpoint function to be removed 543 * 544 * Invoke to remove PCI endpoint function from the endpoint controller. 545 */ 546 void pci_epc_remove_epf(struct pci_epc *epc, struct pci_epf *epf) 547 { 548 if (!epc || IS_ERR(epc) || !epf) 549 return; 550 551 mutex_lock(&epc->lock); 552 clear_bit(epf->func_no, &epc->function_num_map); 553 list_del(&epf->list); 554 epf->epc = NULL; 555 mutex_unlock(&epc->lock); 556 } 557 EXPORT_SYMBOL_GPL(pci_epc_remove_epf); 558 559 /** 560 * pci_epc_linkup() - Notify the EPF device that EPC device has established a 561 * connection with the Root Complex. 562 * @epc: the EPC device which has established link with the host 563 * 564 * Invoke to Notify the EPF device that the EPC device has established a 565 * connection with the Root Complex. 566 */ 567 void pci_epc_linkup(struct pci_epc *epc) 568 { 569 if (!epc || IS_ERR(epc)) 570 return; 571 572 atomic_notifier_call_chain(&epc->notifier, LINK_UP, NULL); 573 } 574 EXPORT_SYMBOL_GPL(pci_epc_linkup); 575 576 /** 577 * pci_epc_init_notify() - Notify the EPF device that EPC device's core 578 * initialization is completed. 579 * @epc: the EPC device whose core initialization is completeds 580 * 581 * Invoke to Notify the EPF device that the EPC device's initialization 582 * is completed. 583 */ 584 void pci_epc_init_notify(struct pci_epc *epc) 585 { 586 if (!epc || IS_ERR(epc)) 587 return; 588 589 atomic_notifier_call_chain(&epc->notifier, CORE_INIT, NULL); 590 } 591 EXPORT_SYMBOL_GPL(pci_epc_init_notify); 592 593 /** 594 * pci_epc_destroy() - destroy the EPC device 595 * @epc: the EPC device that has to be destroyed 596 * 597 * Invoke to destroy the PCI EPC device 598 */ 599 void pci_epc_destroy(struct pci_epc *epc) 600 { 601 pci_ep_cfs_remove_epc_group(epc->group); 602 device_unregister(&epc->dev); 603 kfree(epc); 604 } 605 EXPORT_SYMBOL_GPL(pci_epc_destroy); 606 607 /** 608 * devm_pci_epc_destroy() - destroy the EPC device 609 * @dev: device that wants to destroy the EPC 610 * @epc: the EPC device that has to be destroyed 611 * 612 * Invoke to destroy the devres associated with this 613 * pci_epc and destroy the EPC device. 614 */ 615 void devm_pci_epc_destroy(struct device *dev, struct pci_epc *epc) 616 { 617 int r; 618 619 r = devres_destroy(dev, devm_pci_epc_release, devm_pci_epc_match, 620 epc); 621 dev_WARN_ONCE(dev, r, "couldn't find PCI EPC resource\n"); 622 } 623 EXPORT_SYMBOL_GPL(devm_pci_epc_destroy); 624 625 /** 626 * __pci_epc_create() - create a new endpoint controller (EPC) device 627 * @dev: device that is creating the new EPC 628 * @ops: function pointers for performing EPC operations 629 * @owner: the owner of the module that creates the EPC device 630 * 631 * Invoke to create a new EPC device and add it to pci_epc class. 632 */ 633 struct pci_epc * 634 __pci_epc_create(struct device *dev, const struct pci_epc_ops *ops, 635 struct module *owner) 636 { 637 int ret; 638 struct pci_epc *epc; 639 640 if (WARN_ON(!dev)) { 641 ret = -EINVAL; 642 goto err_ret; 643 } 644 645 epc = kzalloc(sizeof(*epc), GFP_KERNEL); 646 if (!epc) { 647 ret = -ENOMEM; 648 goto err_ret; 649 } 650 651 mutex_init(&epc->lock); 652 INIT_LIST_HEAD(&epc->pci_epf); 653 ATOMIC_INIT_NOTIFIER_HEAD(&epc->notifier); 654 655 device_initialize(&epc->dev); 656 epc->dev.class = pci_epc_class; 657 epc->dev.parent = dev; 658 epc->ops = ops; 659 660 ret = dev_set_name(&epc->dev, "%s", dev_name(dev)); 661 if (ret) 662 goto put_dev; 663 664 ret = device_add(&epc->dev); 665 if (ret) 666 goto put_dev; 667 668 epc->group = pci_ep_cfs_add_epc_group(dev_name(dev)); 669 670 return epc; 671 672 put_dev: 673 put_device(&epc->dev); 674 kfree(epc); 675 676 err_ret: 677 return ERR_PTR(ret); 678 } 679 EXPORT_SYMBOL_GPL(__pci_epc_create); 680 681 /** 682 * __devm_pci_epc_create() - create a new endpoint controller (EPC) device 683 * @dev: device that is creating the new EPC 684 * @ops: function pointers for performing EPC operations 685 * @owner: the owner of the module that creates the EPC device 686 * 687 * Invoke to create a new EPC device and add it to pci_epc class. 688 * While at that, it also associates the device with the pci_epc using devres. 689 * On driver detach, release function is invoked on the devres data, 690 * then, devres data is freed. 691 */ 692 struct pci_epc * 693 __devm_pci_epc_create(struct device *dev, const struct pci_epc_ops *ops, 694 struct module *owner) 695 { 696 struct pci_epc **ptr, *epc; 697 698 ptr = devres_alloc(devm_pci_epc_release, sizeof(*ptr), GFP_KERNEL); 699 if (!ptr) 700 return ERR_PTR(-ENOMEM); 701 702 epc = __pci_epc_create(dev, ops, owner); 703 if (!IS_ERR(epc)) { 704 *ptr = epc; 705 devres_add(dev, ptr); 706 } else { 707 devres_free(ptr); 708 } 709 710 return epc; 711 } 712 EXPORT_SYMBOL_GPL(__devm_pci_epc_create); 713 714 static int __init pci_epc_init(void) 715 { 716 pci_epc_class = class_create(THIS_MODULE, "pci_epc"); 717 if (IS_ERR(pci_epc_class)) { 718 pr_err("failed to create pci epc class --> %ld\n", 719 PTR_ERR(pci_epc_class)); 720 return PTR_ERR(pci_epc_class); 721 } 722 723 return 0; 724 } 725 module_init(pci_epc_init); 726 727 static void __exit pci_epc_exit(void) 728 { 729 class_destroy(pci_epc_class); 730 } 731 module_exit(pci_epc_exit); 732 733 MODULE_DESCRIPTION("PCI EPC Library"); 734 MODULE_AUTHOR("Kishon Vijay Abraham I <kishon@ti.com>"); 735 MODULE_LICENSE("GPL v2"); 736