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v6.8
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * configfs to configure the PCI endpoint
  4 *
  5 * Copyright (C) 2017 Texas Instruments
  6 * Author: Kishon Vijay Abraham I <kishon@ti.com>
  7 */
  8
  9#include <linux/module.h>
 10#include <linux/idr.h>
 11#include <linux/slab.h>
 12
 13#include <linux/pci-epc.h>
 14#include <linux/pci-epf.h>
 15#include <linux/pci-ep-cfs.h>
 16
 17static DEFINE_IDR(functions_idr);
 18static DEFINE_MUTEX(functions_mutex);
 19static struct config_group *functions_group;
 20static struct config_group *controllers_group;
 21
 22struct pci_epf_group {
 23	struct config_group group;
 24	struct config_group primary_epc_group;
 25	struct config_group secondary_epc_group;
 26	struct config_group *type_group;
 27	struct delayed_work cfs_work;
 28	struct pci_epf *epf;
 29	int index;
 30};
 31
 32struct pci_epc_group {
 33	struct config_group group;
 34	struct pci_epc *epc;
 35	bool start;
 36};
 37
 38static inline struct pci_epf_group *to_pci_epf_group(struct config_item *item)
 39{
 40	return container_of(to_config_group(item), struct pci_epf_group, group);
 41}
 42
 43static inline struct pci_epc_group *to_pci_epc_group(struct config_item *item)
 44{
 45	return container_of(to_config_group(item), struct pci_epc_group, group);
 46}
 47
 48static int pci_secondary_epc_epf_link(struct config_item *epf_item,
 49				      struct config_item *epc_item)
 50{
 51	int ret;
 52	struct pci_epf_group *epf_group = to_pci_epf_group(epf_item->ci_parent);
 53	struct pci_epc_group *epc_group = to_pci_epc_group(epc_item);
 54	struct pci_epc *epc = epc_group->epc;
 55	struct pci_epf *epf = epf_group->epf;
 56
 57	ret = pci_epc_add_epf(epc, epf, SECONDARY_INTERFACE);
 58	if (ret)
 59		return ret;
 60
 61	ret = pci_epf_bind(epf);
 62	if (ret) {
 63		pci_epc_remove_epf(epc, epf, SECONDARY_INTERFACE);
 64		return ret;
 65	}
 66
 67	return 0;
 68}
 69
 70static void pci_secondary_epc_epf_unlink(struct config_item *epc_item,
 71					 struct config_item *epf_item)
 72{
 73	struct pci_epf_group *epf_group = to_pci_epf_group(epf_item->ci_parent);
 74	struct pci_epc_group *epc_group = to_pci_epc_group(epc_item);
 75	struct pci_epc *epc;
 76	struct pci_epf *epf;
 77
 78	WARN_ON_ONCE(epc_group->start);
 79
 80	epc = epc_group->epc;
 81	epf = epf_group->epf;
 82	pci_epf_unbind(epf);
 83	pci_epc_remove_epf(epc, epf, SECONDARY_INTERFACE);
 84}
 85
 86static struct configfs_item_operations pci_secondary_epc_item_ops = {
 87	.allow_link	= pci_secondary_epc_epf_link,
 88	.drop_link	= pci_secondary_epc_epf_unlink,
 89};
 90
 91static const struct config_item_type pci_secondary_epc_type = {
 92	.ct_item_ops	= &pci_secondary_epc_item_ops,
 93	.ct_owner	= THIS_MODULE,
 94};
 95
 96static struct config_group
 97*pci_ep_cfs_add_secondary_group(struct pci_epf_group *epf_group)
 98{
 99	struct config_group *secondary_epc_group;
100
101	secondary_epc_group = &epf_group->secondary_epc_group;
102	config_group_init_type_name(secondary_epc_group, "secondary",
103				    &pci_secondary_epc_type);
104	configfs_register_group(&epf_group->group, secondary_epc_group);
105
106	return secondary_epc_group;
107}
108
109static int pci_primary_epc_epf_link(struct config_item *epf_item,
110				    struct config_item *epc_item)
111{
112	int ret;
113	struct pci_epf_group *epf_group = to_pci_epf_group(epf_item->ci_parent);
114	struct pci_epc_group *epc_group = to_pci_epc_group(epc_item);
115	struct pci_epc *epc = epc_group->epc;
116	struct pci_epf *epf = epf_group->epf;
117
118	ret = pci_epc_add_epf(epc, epf, PRIMARY_INTERFACE);
119	if (ret)
120		return ret;
121
122	ret = pci_epf_bind(epf);
123	if (ret) {
124		pci_epc_remove_epf(epc, epf, PRIMARY_INTERFACE);
125		return ret;
126	}
127
128	return 0;
129}
130
131static void pci_primary_epc_epf_unlink(struct config_item *epc_item,
132				       struct config_item *epf_item)
133{
134	struct pci_epf_group *epf_group = to_pci_epf_group(epf_item->ci_parent);
135	struct pci_epc_group *epc_group = to_pci_epc_group(epc_item);
136	struct pci_epc *epc;
137	struct pci_epf *epf;
138
139	WARN_ON_ONCE(epc_group->start);
140
141	epc = epc_group->epc;
142	epf = epf_group->epf;
143	pci_epf_unbind(epf);
144	pci_epc_remove_epf(epc, epf, PRIMARY_INTERFACE);
145}
146
147static struct configfs_item_operations pci_primary_epc_item_ops = {
148	.allow_link	= pci_primary_epc_epf_link,
149	.drop_link	= pci_primary_epc_epf_unlink,
150};
151
152static const struct config_item_type pci_primary_epc_type = {
153	.ct_item_ops	= &pci_primary_epc_item_ops,
154	.ct_owner	= THIS_MODULE,
155};
156
157static struct config_group
158*pci_ep_cfs_add_primary_group(struct pci_epf_group *epf_group)
159{
160	struct config_group *primary_epc_group = &epf_group->primary_epc_group;
161
162	config_group_init_type_name(primary_epc_group, "primary",
163				    &pci_primary_epc_type);
164	configfs_register_group(&epf_group->group, primary_epc_group);
165
166	return primary_epc_group;
167}
168
169static ssize_t pci_epc_start_store(struct config_item *item, const char *page,
170				   size_t len)
171{
172	int ret;
173	bool start;
174	struct pci_epc *epc;
175	struct pci_epc_group *epc_group = to_pci_epc_group(item);
176
177	epc = epc_group->epc;
178
179	if (kstrtobool(page, &start) < 0)
180		return -EINVAL;
181
182	if (start == epc_group->start)
183		return -EALREADY;
184
185	if (!start) {
186		pci_epc_stop(epc);
187		epc_group->start = 0;
188		return len;
189	}
190
191	ret = pci_epc_start(epc);
192	if (ret) {
193		dev_err(&epc->dev, "failed to start endpoint controller\n");
194		return -EINVAL;
195	}
196
197	epc_group->start = start;
198
199	return len;
200}
201
202static ssize_t pci_epc_start_show(struct config_item *item, char *page)
203{
204	return sysfs_emit(page, "%d\n", to_pci_epc_group(item)->start);
 
205}
206
207CONFIGFS_ATTR(pci_epc_, start);
208
209static struct configfs_attribute *pci_epc_attrs[] = {
210	&pci_epc_attr_start,
211	NULL,
212};
213
214static int pci_epc_epf_link(struct config_item *epc_item,
215			    struct config_item *epf_item)
216{
217	int ret;
218	struct pci_epf_group *epf_group = to_pci_epf_group(epf_item);
219	struct pci_epc_group *epc_group = to_pci_epc_group(epc_item);
220	struct pci_epc *epc = epc_group->epc;
221	struct pci_epf *epf = epf_group->epf;
222
223	ret = pci_epc_add_epf(epc, epf, PRIMARY_INTERFACE);
224	if (ret)
225		return ret;
226
227	ret = pci_epf_bind(epf);
228	if (ret) {
229		pci_epc_remove_epf(epc, epf, PRIMARY_INTERFACE);
230		return ret;
231	}
232
233	return 0;
234}
235
236static void pci_epc_epf_unlink(struct config_item *epc_item,
237			       struct config_item *epf_item)
238{
239	struct pci_epc *epc;
240	struct pci_epf *epf;
241	struct pci_epf_group *epf_group = to_pci_epf_group(epf_item);
242	struct pci_epc_group *epc_group = to_pci_epc_group(epc_item);
243
244	WARN_ON_ONCE(epc_group->start);
245
246	epc = epc_group->epc;
247	epf = epf_group->epf;
248	pci_epf_unbind(epf);
249	pci_epc_remove_epf(epc, epf, PRIMARY_INTERFACE);
250}
251
252static struct configfs_item_operations pci_epc_item_ops = {
253	.allow_link	= pci_epc_epf_link,
254	.drop_link	= pci_epc_epf_unlink,
255};
256
257static const struct config_item_type pci_epc_type = {
258	.ct_item_ops	= &pci_epc_item_ops,
259	.ct_attrs	= pci_epc_attrs,
260	.ct_owner	= THIS_MODULE,
261};
262
263struct config_group *pci_ep_cfs_add_epc_group(const char *name)
264{
265	int ret;
266	struct pci_epc *epc;
267	struct config_group *group;
268	struct pci_epc_group *epc_group;
269
270	epc_group = kzalloc(sizeof(*epc_group), GFP_KERNEL);
271	if (!epc_group) {
272		ret = -ENOMEM;
273		goto err;
274	}
275
276	group = &epc_group->group;
277
278	config_group_init_type_name(group, name, &pci_epc_type);
279	ret = configfs_register_group(controllers_group, group);
280	if (ret) {
281		pr_err("failed to register configfs group for %s\n", name);
282		goto err_register_group;
283	}
284
285	epc = pci_epc_get(name);
286	if (IS_ERR(epc)) {
287		ret = PTR_ERR(epc);
288		goto err_epc_get;
289	}
290
291	epc_group->epc = epc;
292
293	return group;
294
295err_epc_get:
296	configfs_unregister_group(group);
297
298err_register_group:
299	kfree(epc_group);
300
301err:
302	return ERR_PTR(ret);
303}
304EXPORT_SYMBOL(pci_ep_cfs_add_epc_group);
305
306void pci_ep_cfs_remove_epc_group(struct config_group *group)
307{
308	struct pci_epc_group *epc_group;
309
310	if (!group)
311		return;
312
313	epc_group = container_of(group, struct pci_epc_group, group);
314	pci_epc_put(epc_group->epc);
315	configfs_unregister_group(&epc_group->group);
316	kfree(epc_group);
317}
318EXPORT_SYMBOL(pci_ep_cfs_remove_epc_group);
319
320#define PCI_EPF_HEADER_R(_name)						       \
321static ssize_t pci_epf_##_name##_show(struct config_item *item,	char *page)    \
322{									       \
323	struct pci_epf *epf = to_pci_epf_group(item)->epf;		       \
324	if (WARN_ON_ONCE(!epf->header))					       \
325		return -EINVAL;						       \
326	return sysfs_emit(page, "0x%04x\n", epf->header->_name);	       \
327}
328
329#define PCI_EPF_HEADER_W_u32(_name)					       \
330static ssize_t pci_epf_##_name##_store(struct config_item *item,	       \
331				       const char *page, size_t len)	       \
332{									       \
333	u32 val;							       \
 
334	struct pci_epf *epf = to_pci_epf_group(item)->epf;		       \
335	if (WARN_ON_ONCE(!epf->header))					       \
336		return -EINVAL;						       \
337	if (kstrtou32(page, 0, &val) < 0)				       \
338		return -EINVAL;						       \
 
339	epf->header->_name = val;					       \
340	return len;							       \
341}
342
343#define PCI_EPF_HEADER_W_u16(_name)					       \
344static ssize_t pci_epf_##_name##_store(struct config_item *item,	       \
345				       const char *page, size_t len)	       \
346{									       \
347	u16 val;							       \
 
348	struct pci_epf *epf = to_pci_epf_group(item)->epf;		       \
349	if (WARN_ON_ONCE(!epf->header))					       \
350		return -EINVAL;						       \
351	if (kstrtou16(page, 0, &val) < 0)				       \
352		return -EINVAL;						       \
 
353	epf->header->_name = val;					       \
354	return len;							       \
355}
356
357#define PCI_EPF_HEADER_W_u8(_name)					       \
358static ssize_t pci_epf_##_name##_store(struct config_item *item,	       \
359				       const char *page, size_t len)	       \
360{									       \
361	u8 val;								       \
 
362	struct pci_epf *epf = to_pci_epf_group(item)->epf;		       \
363	if (WARN_ON_ONCE(!epf->header))					       \
364		return -EINVAL;						       \
365	if (kstrtou8(page, 0, &val) < 0)				       \
366		return -EINVAL;						       \
 
367	epf->header->_name = val;					       \
368	return len;							       \
369}
370
371static ssize_t pci_epf_msi_interrupts_store(struct config_item *item,
372					    const char *page, size_t len)
373{
374	u8 val;
 
375
376	if (kstrtou8(page, 0, &val) < 0)
377		return -EINVAL;
 
378
379	to_pci_epf_group(item)->epf->msi_interrupts = val;
380
381	return len;
382}
383
384static ssize_t pci_epf_msi_interrupts_show(struct config_item *item,
385					   char *page)
386{
387	return sysfs_emit(page, "%d\n",
388			  to_pci_epf_group(item)->epf->msi_interrupts);
389}
390
391static ssize_t pci_epf_msix_interrupts_store(struct config_item *item,
392					     const char *page, size_t len)
393{
394	u16 val;
 
395
396	if (kstrtou16(page, 0, &val) < 0)
397		return -EINVAL;
 
398
399	to_pci_epf_group(item)->epf->msix_interrupts = val;
400
401	return len;
402}
403
404static ssize_t pci_epf_msix_interrupts_show(struct config_item *item,
405					    char *page)
406{
407	return sysfs_emit(page, "%d\n",
408			  to_pci_epf_group(item)->epf->msix_interrupts);
409}
410
411PCI_EPF_HEADER_R(vendorid)
412PCI_EPF_HEADER_W_u16(vendorid)
413
414PCI_EPF_HEADER_R(deviceid)
415PCI_EPF_HEADER_W_u16(deviceid)
416
417PCI_EPF_HEADER_R(revid)
418PCI_EPF_HEADER_W_u8(revid)
419
420PCI_EPF_HEADER_R(progif_code)
421PCI_EPF_HEADER_W_u8(progif_code)
422
423PCI_EPF_HEADER_R(subclass_code)
424PCI_EPF_HEADER_W_u8(subclass_code)
425
426PCI_EPF_HEADER_R(baseclass_code)
427PCI_EPF_HEADER_W_u8(baseclass_code)
428
429PCI_EPF_HEADER_R(cache_line_size)
430PCI_EPF_HEADER_W_u8(cache_line_size)
431
432PCI_EPF_HEADER_R(subsys_vendor_id)
433PCI_EPF_HEADER_W_u16(subsys_vendor_id)
434
435PCI_EPF_HEADER_R(subsys_id)
436PCI_EPF_HEADER_W_u16(subsys_id)
437
438PCI_EPF_HEADER_R(interrupt_pin)
439PCI_EPF_HEADER_W_u8(interrupt_pin)
440
441CONFIGFS_ATTR(pci_epf_, vendorid);
442CONFIGFS_ATTR(pci_epf_, deviceid);
443CONFIGFS_ATTR(pci_epf_, revid);
444CONFIGFS_ATTR(pci_epf_, progif_code);
445CONFIGFS_ATTR(pci_epf_, subclass_code);
446CONFIGFS_ATTR(pci_epf_, baseclass_code);
447CONFIGFS_ATTR(pci_epf_, cache_line_size);
448CONFIGFS_ATTR(pci_epf_, subsys_vendor_id);
449CONFIGFS_ATTR(pci_epf_, subsys_id);
450CONFIGFS_ATTR(pci_epf_, interrupt_pin);
451CONFIGFS_ATTR(pci_epf_, msi_interrupts);
452CONFIGFS_ATTR(pci_epf_, msix_interrupts);
453
454static struct configfs_attribute *pci_epf_attrs[] = {
455	&pci_epf_attr_vendorid,
456	&pci_epf_attr_deviceid,
457	&pci_epf_attr_revid,
458	&pci_epf_attr_progif_code,
459	&pci_epf_attr_subclass_code,
460	&pci_epf_attr_baseclass_code,
461	&pci_epf_attr_cache_line_size,
462	&pci_epf_attr_subsys_vendor_id,
463	&pci_epf_attr_subsys_id,
464	&pci_epf_attr_interrupt_pin,
465	&pci_epf_attr_msi_interrupts,
466	&pci_epf_attr_msix_interrupts,
467	NULL,
468};
469
470static int pci_epf_vepf_link(struct config_item *epf_pf_item,
471			     struct config_item *epf_vf_item)
472{
473	struct pci_epf_group *epf_vf_group = to_pci_epf_group(epf_vf_item);
474	struct pci_epf_group *epf_pf_group = to_pci_epf_group(epf_pf_item);
475	struct pci_epf *epf_pf = epf_pf_group->epf;
476	struct pci_epf *epf_vf = epf_vf_group->epf;
477
478	return pci_epf_add_vepf(epf_pf, epf_vf);
479}
480
481static void pci_epf_vepf_unlink(struct config_item *epf_pf_item,
482				struct config_item *epf_vf_item)
483{
484	struct pci_epf_group *epf_vf_group = to_pci_epf_group(epf_vf_item);
485	struct pci_epf_group *epf_pf_group = to_pci_epf_group(epf_pf_item);
486	struct pci_epf *epf_pf = epf_pf_group->epf;
487	struct pci_epf *epf_vf = epf_vf_group->epf;
488
489	pci_epf_remove_vepf(epf_pf, epf_vf);
490}
491
492static void pci_epf_release(struct config_item *item)
493{
494	struct pci_epf_group *epf_group = to_pci_epf_group(item);
495
496	mutex_lock(&functions_mutex);
497	idr_remove(&functions_idr, epf_group->index);
498	mutex_unlock(&functions_mutex);
499	pci_epf_destroy(epf_group->epf);
500	kfree(epf_group);
501}
502
503static struct configfs_item_operations pci_epf_ops = {
504	.allow_link		= pci_epf_vepf_link,
505	.drop_link		= pci_epf_vepf_unlink,
506	.release		= pci_epf_release,
507};
508
509static const struct config_item_type pci_epf_type = {
510	.ct_item_ops	= &pci_epf_ops,
511	.ct_attrs	= pci_epf_attrs,
512	.ct_owner	= THIS_MODULE,
513};
514
515/**
516 * pci_epf_type_add_cfs() - Help function drivers to expose function specific
517 *                          attributes in configfs
518 * @epf: the EPF device that has to be configured using configfs
519 * @group: the parent configfs group (corresponding to entries in
520 *         pci_epf_device_id)
521 *
522 * Invoke to expose function specific attributes in configfs.
523 *
524 * Return: A pointer to a config_group structure or NULL if the function driver
525 * does not have anything to expose (attributes configured by user) or if
526 * the function driver does not implement the add_cfs() method.
527 *
528 * Returns an error pointer if this function is called for an unbound EPF device
529 * or if the EPF driver add_cfs() method fails.
530 */
531static struct config_group *pci_epf_type_add_cfs(struct pci_epf *epf,
532						 struct config_group *group)
533{
 
534	struct config_group *epf_type_group;
535
536	if (!epf->driver) {
537		dev_err(&epf->dev, "epf device not bound to driver\n");
538		return ERR_PTR(-ENODEV);
539	}
540
541	if (!epf->driver->ops->add_cfs)
542		return NULL;
543
544	mutex_lock(&epf->lock);
545	epf_type_group = epf->driver->ops->add_cfs(epf, group);
546	mutex_unlock(&epf->lock);
547
548	return epf_type_group;
549}
550
551static void pci_ep_cfs_add_type_group(struct pci_epf_group *epf_group)
 
552{
553	struct config_group *group;
554
555	group = pci_epf_type_add_cfs(epf_group->epf, &epf_group->group);
556	if (!group)
557		return;
558
559	if (IS_ERR(group)) {
560		dev_err(&epf_group->epf->dev,
561			"failed to create epf type specific attributes\n");
562		return;
563	}
564
565	configfs_register_group(&epf_group->group, group);
566}
 
 
 
 
567
568static void pci_epf_cfs_work(struct work_struct *work)
569{
570	struct pci_epf_group *epf_group;
571	struct config_group *group;
572
573	epf_group = container_of(work, struct pci_epf_group, cfs_work.work);
574	group = pci_ep_cfs_add_primary_group(epf_group);
575	if (IS_ERR(group)) {
576		pr_err("failed to create 'primary' EPC interface\n");
577		return;
578	}
579
580	group = pci_ep_cfs_add_secondary_group(epf_group);
581	if (IS_ERR(group)) {
582		pr_err("failed to create 'secondary' EPC interface\n");
583		return;
584	}
585
586	pci_ep_cfs_add_type_group(epf_group);
587}
588
589static struct config_group *pci_epf_make(struct config_group *group,
590					 const char *name)
591{
592	struct pci_epf_group *epf_group;
593	struct pci_epf *epf;
594	char *epf_name;
595	int index, err;
596
597	epf_group = kzalloc(sizeof(*epf_group), GFP_KERNEL);
598	if (!epf_group)
599		return ERR_PTR(-ENOMEM);
600
601	mutex_lock(&functions_mutex);
602	index = idr_alloc(&functions_idr, epf_group, 0, 0, GFP_KERNEL);
603	mutex_unlock(&functions_mutex);
604	if (index < 0) {
605		err = index;
606		goto free_group;
607	}
608
609	epf_group->index = index;
610
611	config_group_init_type_name(&epf_group->group, name, &pci_epf_type);
612
613	epf_name = kasprintf(GFP_KERNEL, "%s.%d",
614			     group->cg_item.ci_name, epf_group->index);
615	if (!epf_name) {
616		err = -ENOMEM;
617		goto remove_idr;
618	}
619
620	epf = pci_epf_create(epf_name);
621	if (IS_ERR(epf)) {
622		pr_err("failed to create endpoint function device\n");
623		err = -EINVAL;
624		goto free_name;
625	}
626
627	epf->group = &epf_group->group;
628	epf_group->epf = epf;
629
630	kfree(epf_name);
631
632	INIT_DELAYED_WORK(&epf_group->cfs_work, pci_epf_cfs_work);
633	queue_delayed_work(system_wq, &epf_group->cfs_work,
634			   msecs_to_jiffies(1));
635
636	return &epf_group->group;
637
638free_name:
639	kfree(epf_name);
640
641remove_idr:
642	mutex_lock(&functions_mutex);
643	idr_remove(&functions_idr, epf_group->index);
644	mutex_unlock(&functions_mutex);
645
646free_group:
647	kfree(epf_group);
648
649	return ERR_PTR(err);
650}
651
652static void pci_epf_drop(struct config_group *group, struct config_item *item)
653{
654	config_item_put(item);
655}
656
657static struct configfs_group_operations pci_epf_group_ops = {
658	.make_group     = &pci_epf_make,
659	.drop_item      = &pci_epf_drop,
660};
661
662static const struct config_item_type pci_epf_group_type = {
663	.ct_group_ops	= &pci_epf_group_ops,
664	.ct_owner	= THIS_MODULE,
665};
666
667struct config_group *pci_ep_cfs_add_epf_group(const char *name)
668{
669	struct config_group *group;
670
671	group = configfs_register_default_group(functions_group, name,
672						&pci_epf_group_type);
673	if (IS_ERR(group))
674		pr_err("failed to register configfs group for %s function\n",
675		       name);
676
677	return group;
678}
679EXPORT_SYMBOL(pci_ep_cfs_add_epf_group);
680
681void pci_ep_cfs_remove_epf_group(struct config_group *group)
682{
683	if (IS_ERR_OR_NULL(group))
684		return;
685
686	configfs_unregister_default_group(group);
687}
688EXPORT_SYMBOL(pci_ep_cfs_remove_epf_group);
689
690static const struct config_item_type pci_functions_type = {
691	.ct_owner	= THIS_MODULE,
692};
693
694static const struct config_item_type pci_controllers_type = {
695	.ct_owner	= THIS_MODULE,
696};
697
698static const struct config_item_type pci_ep_type = {
699	.ct_owner	= THIS_MODULE,
700};
701
702static struct configfs_subsystem pci_ep_cfs_subsys = {
703	.su_group = {
704		.cg_item = {
705			.ci_namebuf = "pci_ep",
706			.ci_type = &pci_ep_type,
707		},
708	},
709	.su_mutex = __MUTEX_INITIALIZER(pci_ep_cfs_subsys.su_mutex),
710};
711
712static int __init pci_ep_cfs_init(void)
713{
714	int ret;
715	struct config_group *root = &pci_ep_cfs_subsys.su_group;
716
717	config_group_init(root);
718
719	ret = configfs_register_subsystem(&pci_ep_cfs_subsys);
720	if (ret) {
721		pr_err("Error %d while registering subsystem %s\n",
722		       ret, root->cg_item.ci_namebuf);
723		goto err;
724	}
725
726	functions_group = configfs_register_default_group(root, "functions",
727							  &pci_functions_type);
728	if (IS_ERR(functions_group)) {
729		ret = PTR_ERR(functions_group);
730		pr_err("Error %d while registering functions group\n",
731		       ret);
732		goto err_functions_group;
733	}
734
735	controllers_group =
736		configfs_register_default_group(root, "controllers",
737						&pci_controllers_type);
738	if (IS_ERR(controllers_group)) {
739		ret = PTR_ERR(controllers_group);
740		pr_err("Error %d while registering controllers group\n",
741		       ret);
742		goto err_controllers_group;
743	}
744
745	return 0;
746
747err_controllers_group:
748	configfs_unregister_default_group(functions_group);
749
750err_functions_group:
751	configfs_unregister_subsystem(&pci_ep_cfs_subsys);
752
753err:
754	return ret;
755}
756module_init(pci_ep_cfs_init);
757
758static void __exit pci_ep_cfs_exit(void)
759{
760	configfs_unregister_default_group(controllers_group);
761	configfs_unregister_default_group(functions_group);
762	configfs_unregister_subsystem(&pci_ep_cfs_subsys);
763}
764module_exit(pci_ep_cfs_exit);
765
766MODULE_DESCRIPTION("PCI EP CONFIGFS");
767MODULE_AUTHOR("Kishon Vijay Abraham I <kishon@ti.com>");
v5.14.15
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * configfs to configure the PCI endpoint
  4 *
  5 * Copyright (C) 2017 Texas Instruments
  6 * Author: Kishon Vijay Abraham I <kishon@ti.com>
  7 */
  8
  9#include <linux/module.h>
 10#include <linux/idr.h>
 11#include <linux/slab.h>
 12
 13#include <linux/pci-epc.h>
 14#include <linux/pci-epf.h>
 15#include <linux/pci-ep-cfs.h>
 16
 17static DEFINE_IDR(functions_idr);
 18static DEFINE_MUTEX(functions_mutex);
 19static struct config_group *functions_group;
 20static struct config_group *controllers_group;
 21
 22struct pci_epf_group {
 23	struct config_group group;
 24	struct config_group primary_epc_group;
 25	struct config_group secondary_epc_group;
 
 26	struct delayed_work cfs_work;
 27	struct pci_epf *epf;
 28	int index;
 29};
 30
 31struct pci_epc_group {
 32	struct config_group group;
 33	struct pci_epc *epc;
 34	bool start;
 35};
 36
 37static inline struct pci_epf_group *to_pci_epf_group(struct config_item *item)
 38{
 39	return container_of(to_config_group(item), struct pci_epf_group, group);
 40}
 41
 42static inline struct pci_epc_group *to_pci_epc_group(struct config_item *item)
 43{
 44	return container_of(to_config_group(item), struct pci_epc_group, group);
 45}
 46
 47static int pci_secondary_epc_epf_link(struct config_item *epf_item,
 48				      struct config_item *epc_item)
 49{
 50	int ret;
 51	struct pci_epf_group *epf_group = to_pci_epf_group(epf_item->ci_parent);
 52	struct pci_epc_group *epc_group = to_pci_epc_group(epc_item);
 53	struct pci_epc *epc = epc_group->epc;
 54	struct pci_epf *epf = epf_group->epf;
 55
 56	ret = pci_epc_add_epf(epc, epf, SECONDARY_INTERFACE);
 57	if (ret)
 58		return ret;
 59
 60	ret = pci_epf_bind(epf);
 61	if (ret) {
 62		pci_epc_remove_epf(epc, epf, SECONDARY_INTERFACE);
 63		return ret;
 64	}
 65
 66	return 0;
 67}
 68
 69static void pci_secondary_epc_epf_unlink(struct config_item *epc_item,
 70					 struct config_item *epf_item)
 71{
 72	struct pci_epf_group *epf_group = to_pci_epf_group(epf_item->ci_parent);
 73	struct pci_epc_group *epc_group = to_pci_epc_group(epc_item);
 74	struct pci_epc *epc;
 75	struct pci_epf *epf;
 76
 77	WARN_ON_ONCE(epc_group->start);
 78
 79	epc = epc_group->epc;
 80	epf = epf_group->epf;
 81	pci_epf_unbind(epf);
 82	pci_epc_remove_epf(epc, epf, SECONDARY_INTERFACE);
 83}
 84
 85static struct configfs_item_operations pci_secondary_epc_item_ops = {
 86	.allow_link	= pci_secondary_epc_epf_link,
 87	.drop_link	= pci_secondary_epc_epf_unlink,
 88};
 89
 90static const struct config_item_type pci_secondary_epc_type = {
 91	.ct_item_ops	= &pci_secondary_epc_item_ops,
 92	.ct_owner	= THIS_MODULE,
 93};
 94
 95static struct config_group
 96*pci_ep_cfs_add_secondary_group(struct pci_epf_group *epf_group)
 97{
 98	struct config_group *secondary_epc_group;
 99
100	secondary_epc_group = &epf_group->secondary_epc_group;
101	config_group_init_type_name(secondary_epc_group, "secondary",
102				    &pci_secondary_epc_type);
103	configfs_register_group(&epf_group->group, secondary_epc_group);
104
105	return secondary_epc_group;
106}
107
108static int pci_primary_epc_epf_link(struct config_item *epf_item,
109				    struct config_item *epc_item)
110{
111	int ret;
112	struct pci_epf_group *epf_group = to_pci_epf_group(epf_item->ci_parent);
113	struct pci_epc_group *epc_group = to_pci_epc_group(epc_item);
114	struct pci_epc *epc = epc_group->epc;
115	struct pci_epf *epf = epf_group->epf;
116
117	ret = pci_epc_add_epf(epc, epf, PRIMARY_INTERFACE);
118	if (ret)
119		return ret;
120
121	ret = pci_epf_bind(epf);
122	if (ret) {
123		pci_epc_remove_epf(epc, epf, PRIMARY_INTERFACE);
124		return ret;
125	}
126
127	return 0;
128}
129
130static void pci_primary_epc_epf_unlink(struct config_item *epc_item,
131				       struct config_item *epf_item)
132{
133	struct pci_epf_group *epf_group = to_pci_epf_group(epf_item->ci_parent);
134	struct pci_epc_group *epc_group = to_pci_epc_group(epc_item);
135	struct pci_epc *epc;
136	struct pci_epf *epf;
137
138	WARN_ON_ONCE(epc_group->start);
139
140	epc = epc_group->epc;
141	epf = epf_group->epf;
142	pci_epf_unbind(epf);
143	pci_epc_remove_epf(epc, epf, PRIMARY_INTERFACE);
144}
145
146static struct configfs_item_operations pci_primary_epc_item_ops = {
147	.allow_link	= pci_primary_epc_epf_link,
148	.drop_link	= pci_primary_epc_epf_unlink,
149};
150
151static const struct config_item_type pci_primary_epc_type = {
152	.ct_item_ops	= &pci_primary_epc_item_ops,
153	.ct_owner	= THIS_MODULE,
154};
155
156static struct config_group
157*pci_ep_cfs_add_primary_group(struct pci_epf_group *epf_group)
158{
159	struct config_group *primary_epc_group = &epf_group->primary_epc_group;
160
161	config_group_init_type_name(primary_epc_group, "primary",
162				    &pci_primary_epc_type);
163	configfs_register_group(&epf_group->group, primary_epc_group);
164
165	return primary_epc_group;
166}
167
168static ssize_t pci_epc_start_store(struct config_item *item, const char *page,
169				   size_t len)
170{
171	int ret;
172	bool start;
173	struct pci_epc *epc;
174	struct pci_epc_group *epc_group = to_pci_epc_group(item);
175
176	epc = epc_group->epc;
177
178	ret = kstrtobool(page, &start);
179	if (ret)
180		return ret;
 
 
181
182	if (!start) {
183		pci_epc_stop(epc);
184		epc_group->start = 0;
185		return len;
186	}
187
188	ret = pci_epc_start(epc);
189	if (ret) {
190		dev_err(&epc->dev, "failed to start endpoint controller\n");
191		return -EINVAL;
192	}
193
194	epc_group->start = start;
195
196	return len;
197}
198
199static ssize_t pci_epc_start_show(struct config_item *item, char *page)
200{
201	return sprintf(page, "%d\n",
202		       to_pci_epc_group(item)->start);
203}
204
205CONFIGFS_ATTR(pci_epc_, start);
206
207static struct configfs_attribute *pci_epc_attrs[] = {
208	&pci_epc_attr_start,
209	NULL,
210};
211
212static int pci_epc_epf_link(struct config_item *epc_item,
213			    struct config_item *epf_item)
214{
215	int ret;
216	struct pci_epf_group *epf_group = to_pci_epf_group(epf_item);
217	struct pci_epc_group *epc_group = to_pci_epc_group(epc_item);
218	struct pci_epc *epc = epc_group->epc;
219	struct pci_epf *epf = epf_group->epf;
220
221	ret = pci_epc_add_epf(epc, epf, PRIMARY_INTERFACE);
222	if (ret)
223		return ret;
224
225	ret = pci_epf_bind(epf);
226	if (ret) {
227		pci_epc_remove_epf(epc, epf, PRIMARY_INTERFACE);
228		return ret;
229	}
230
231	return 0;
232}
233
234static void pci_epc_epf_unlink(struct config_item *epc_item,
235			       struct config_item *epf_item)
236{
237	struct pci_epc *epc;
238	struct pci_epf *epf;
239	struct pci_epf_group *epf_group = to_pci_epf_group(epf_item);
240	struct pci_epc_group *epc_group = to_pci_epc_group(epc_item);
241
242	WARN_ON_ONCE(epc_group->start);
243
244	epc = epc_group->epc;
245	epf = epf_group->epf;
246	pci_epf_unbind(epf);
247	pci_epc_remove_epf(epc, epf, PRIMARY_INTERFACE);
248}
249
250static struct configfs_item_operations pci_epc_item_ops = {
251	.allow_link	= pci_epc_epf_link,
252	.drop_link	= pci_epc_epf_unlink,
253};
254
255static const struct config_item_type pci_epc_type = {
256	.ct_item_ops	= &pci_epc_item_ops,
257	.ct_attrs	= pci_epc_attrs,
258	.ct_owner	= THIS_MODULE,
259};
260
261struct config_group *pci_ep_cfs_add_epc_group(const char *name)
262{
263	int ret;
264	struct pci_epc *epc;
265	struct config_group *group;
266	struct pci_epc_group *epc_group;
267
268	epc_group = kzalloc(sizeof(*epc_group), GFP_KERNEL);
269	if (!epc_group) {
270		ret = -ENOMEM;
271		goto err;
272	}
273
274	group = &epc_group->group;
275
276	config_group_init_type_name(group, name, &pci_epc_type);
277	ret = configfs_register_group(controllers_group, group);
278	if (ret) {
279		pr_err("failed to register configfs group for %s\n", name);
280		goto err_register_group;
281	}
282
283	epc = pci_epc_get(name);
284	if (IS_ERR(epc)) {
285		ret = PTR_ERR(epc);
286		goto err_epc_get;
287	}
288
289	epc_group->epc = epc;
290
291	return group;
292
293err_epc_get:
294	configfs_unregister_group(group);
295
296err_register_group:
297	kfree(epc_group);
298
299err:
300	return ERR_PTR(ret);
301}
302EXPORT_SYMBOL(pci_ep_cfs_add_epc_group);
303
304void pci_ep_cfs_remove_epc_group(struct config_group *group)
305{
306	struct pci_epc_group *epc_group;
307
308	if (!group)
309		return;
310
311	epc_group = container_of(group, struct pci_epc_group, group);
312	pci_epc_put(epc_group->epc);
313	configfs_unregister_group(&epc_group->group);
314	kfree(epc_group);
315}
316EXPORT_SYMBOL(pci_ep_cfs_remove_epc_group);
317
318#define PCI_EPF_HEADER_R(_name)						       \
319static ssize_t pci_epf_##_name##_show(struct config_item *item,	char *page)    \
320{									       \
321	struct pci_epf *epf = to_pci_epf_group(item)->epf;		       \
322	if (WARN_ON_ONCE(!epf->header))					       \
323		return -EINVAL;						       \
324	return sprintf(page, "0x%04x\n", epf->header->_name);		       \
325}
326
327#define PCI_EPF_HEADER_W_u32(_name)					       \
328static ssize_t pci_epf_##_name##_store(struct config_item *item,	       \
329				       const char *page, size_t len)	       \
330{									       \
331	u32 val;							       \
332	int ret;							       \
333	struct pci_epf *epf = to_pci_epf_group(item)->epf;		       \
334	if (WARN_ON_ONCE(!epf->header))					       \
335		return -EINVAL;						       \
336	ret = kstrtou32(page, 0, &val);					       \
337	if (ret)							       \
338		return ret;						       \
339	epf->header->_name = val;					       \
340	return len;							       \
341}
342
343#define PCI_EPF_HEADER_W_u16(_name)					       \
344static ssize_t pci_epf_##_name##_store(struct config_item *item,	       \
345				       const char *page, size_t len)	       \
346{									       \
347	u16 val;							       \
348	int ret;							       \
349	struct pci_epf *epf = to_pci_epf_group(item)->epf;		       \
350	if (WARN_ON_ONCE(!epf->header))					       \
351		return -EINVAL;						       \
352	ret = kstrtou16(page, 0, &val);					       \
353	if (ret)							       \
354		return ret;						       \
355	epf->header->_name = val;					       \
356	return len;							       \
357}
358
359#define PCI_EPF_HEADER_W_u8(_name)					       \
360static ssize_t pci_epf_##_name##_store(struct config_item *item,	       \
361				       const char *page, size_t len)	       \
362{									       \
363	u8 val;								       \
364	int ret;							       \
365	struct pci_epf *epf = to_pci_epf_group(item)->epf;		       \
366	if (WARN_ON_ONCE(!epf->header))					       \
367		return -EINVAL;						       \
368	ret = kstrtou8(page, 0, &val);					       \
369	if (ret)							       \
370		return ret;						       \
371	epf->header->_name = val;					       \
372	return len;							       \
373}
374
375static ssize_t pci_epf_msi_interrupts_store(struct config_item *item,
376					    const char *page, size_t len)
377{
378	u8 val;
379	int ret;
380
381	ret = kstrtou8(page, 0, &val);
382	if (ret)
383		return ret;
384
385	to_pci_epf_group(item)->epf->msi_interrupts = val;
386
387	return len;
388}
389
390static ssize_t pci_epf_msi_interrupts_show(struct config_item *item,
391					   char *page)
392{
393	return sprintf(page, "%d\n",
394		       to_pci_epf_group(item)->epf->msi_interrupts);
395}
396
397static ssize_t pci_epf_msix_interrupts_store(struct config_item *item,
398					     const char *page, size_t len)
399{
400	u16 val;
401	int ret;
402
403	ret = kstrtou16(page, 0, &val);
404	if (ret)
405		return ret;
406
407	to_pci_epf_group(item)->epf->msix_interrupts = val;
408
409	return len;
410}
411
412static ssize_t pci_epf_msix_interrupts_show(struct config_item *item,
413					    char *page)
414{
415	return sprintf(page, "%d\n",
416		       to_pci_epf_group(item)->epf->msix_interrupts);
417}
418
419PCI_EPF_HEADER_R(vendorid)
420PCI_EPF_HEADER_W_u16(vendorid)
421
422PCI_EPF_HEADER_R(deviceid)
423PCI_EPF_HEADER_W_u16(deviceid)
424
425PCI_EPF_HEADER_R(revid)
426PCI_EPF_HEADER_W_u8(revid)
427
428PCI_EPF_HEADER_R(progif_code)
429PCI_EPF_HEADER_W_u8(progif_code)
430
431PCI_EPF_HEADER_R(subclass_code)
432PCI_EPF_HEADER_W_u8(subclass_code)
433
434PCI_EPF_HEADER_R(baseclass_code)
435PCI_EPF_HEADER_W_u8(baseclass_code)
436
437PCI_EPF_HEADER_R(cache_line_size)
438PCI_EPF_HEADER_W_u8(cache_line_size)
439
440PCI_EPF_HEADER_R(subsys_vendor_id)
441PCI_EPF_HEADER_W_u16(subsys_vendor_id)
442
443PCI_EPF_HEADER_R(subsys_id)
444PCI_EPF_HEADER_W_u16(subsys_id)
445
446PCI_EPF_HEADER_R(interrupt_pin)
447PCI_EPF_HEADER_W_u8(interrupt_pin)
448
449CONFIGFS_ATTR(pci_epf_, vendorid);
450CONFIGFS_ATTR(pci_epf_, deviceid);
451CONFIGFS_ATTR(pci_epf_, revid);
452CONFIGFS_ATTR(pci_epf_, progif_code);
453CONFIGFS_ATTR(pci_epf_, subclass_code);
454CONFIGFS_ATTR(pci_epf_, baseclass_code);
455CONFIGFS_ATTR(pci_epf_, cache_line_size);
456CONFIGFS_ATTR(pci_epf_, subsys_vendor_id);
457CONFIGFS_ATTR(pci_epf_, subsys_id);
458CONFIGFS_ATTR(pci_epf_, interrupt_pin);
459CONFIGFS_ATTR(pci_epf_, msi_interrupts);
460CONFIGFS_ATTR(pci_epf_, msix_interrupts);
461
462static struct configfs_attribute *pci_epf_attrs[] = {
463	&pci_epf_attr_vendorid,
464	&pci_epf_attr_deviceid,
465	&pci_epf_attr_revid,
466	&pci_epf_attr_progif_code,
467	&pci_epf_attr_subclass_code,
468	&pci_epf_attr_baseclass_code,
469	&pci_epf_attr_cache_line_size,
470	&pci_epf_attr_subsys_vendor_id,
471	&pci_epf_attr_subsys_id,
472	&pci_epf_attr_interrupt_pin,
473	&pci_epf_attr_msi_interrupts,
474	&pci_epf_attr_msix_interrupts,
475	NULL,
476};
477
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
478static void pci_epf_release(struct config_item *item)
479{
480	struct pci_epf_group *epf_group = to_pci_epf_group(item);
481
482	mutex_lock(&functions_mutex);
483	idr_remove(&functions_idr, epf_group->index);
484	mutex_unlock(&functions_mutex);
485	pci_epf_destroy(epf_group->epf);
486	kfree(epf_group);
487}
488
489static struct configfs_item_operations pci_epf_ops = {
 
 
490	.release		= pci_epf_release,
491};
492
493static struct config_group *pci_epf_type_make(struct config_group *group,
494					      const char *name)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
495{
496	struct pci_epf_group *epf_group = to_pci_epf_group(&group->cg_item);
497	struct config_group *epf_type_group;
498
499	epf_type_group = pci_epf_type_add_cfs(epf_group->epf, group);
 
 
 
 
 
 
 
 
 
 
 
500	return epf_type_group;
501}
502
503static void pci_epf_type_drop(struct config_group *group,
504			      struct config_item *item)
505{
506	config_item_put(item);
507}
 
 
 
508
509static struct configfs_group_operations pci_epf_type_group_ops = {
510	.make_group     = &pci_epf_type_make,
511	.drop_item      = &pci_epf_type_drop,
512};
 
513
514static const struct config_item_type pci_epf_type = {
515	.ct_group_ops	= &pci_epf_type_group_ops,
516	.ct_item_ops	= &pci_epf_ops,
517	.ct_attrs	= pci_epf_attrs,
518	.ct_owner	= THIS_MODULE,
519};
520
521static void pci_epf_cfs_work(struct work_struct *work)
522{
523	struct pci_epf_group *epf_group;
524	struct config_group *group;
525
526	epf_group = container_of(work, struct pci_epf_group, cfs_work.work);
527	group = pci_ep_cfs_add_primary_group(epf_group);
528	if (IS_ERR(group)) {
529		pr_err("failed to create 'primary' EPC interface\n");
530		return;
531	}
532
533	group = pci_ep_cfs_add_secondary_group(epf_group);
534	if (IS_ERR(group)) {
535		pr_err("failed to create 'secondary' EPC interface\n");
536		return;
537	}
 
 
538}
539
540static struct config_group *pci_epf_make(struct config_group *group,
541					 const char *name)
542{
543	struct pci_epf_group *epf_group;
544	struct pci_epf *epf;
545	char *epf_name;
546	int index, err;
547
548	epf_group = kzalloc(sizeof(*epf_group), GFP_KERNEL);
549	if (!epf_group)
550		return ERR_PTR(-ENOMEM);
551
552	mutex_lock(&functions_mutex);
553	index = idr_alloc(&functions_idr, epf_group, 0, 0, GFP_KERNEL);
554	mutex_unlock(&functions_mutex);
555	if (index < 0) {
556		err = index;
557		goto free_group;
558	}
559
560	epf_group->index = index;
561
562	config_group_init_type_name(&epf_group->group, name, &pci_epf_type);
563
564	epf_name = kasprintf(GFP_KERNEL, "%s.%d",
565			     group->cg_item.ci_name, epf_group->index);
566	if (!epf_name) {
567		err = -ENOMEM;
568		goto remove_idr;
569	}
570
571	epf = pci_epf_create(epf_name);
572	if (IS_ERR(epf)) {
573		pr_err("failed to create endpoint function device\n");
574		err = -EINVAL;
575		goto free_name;
576	}
577
578	epf->group = &epf_group->group;
579	epf_group->epf = epf;
580
581	kfree(epf_name);
582
583	INIT_DELAYED_WORK(&epf_group->cfs_work, pci_epf_cfs_work);
584	queue_delayed_work(system_wq, &epf_group->cfs_work,
585			   msecs_to_jiffies(1));
586
587	return &epf_group->group;
588
589free_name:
590	kfree(epf_name);
591
592remove_idr:
593	mutex_lock(&functions_mutex);
594	idr_remove(&functions_idr, epf_group->index);
595	mutex_unlock(&functions_mutex);
596
597free_group:
598	kfree(epf_group);
599
600	return ERR_PTR(err);
601}
602
603static void pci_epf_drop(struct config_group *group, struct config_item *item)
604{
605	config_item_put(item);
606}
607
608static struct configfs_group_operations pci_epf_group_ops = {
609	.make_group     = &pci_epf_make,
610	.drop_item      = &pci_epf_drop,
611};
612
613static const struct config_item_type pci_epf_group_type = {
614	.ct_group_ops	= &pci_epf_group_ops,
615	.ct_owner	= THIS_MODULE,
616};
617
618struct config_group *pci_ep_cfs_add_epf_group(const char *name)
619{
620	struct config_group *group;
621
622	group = configfs_register_default_group(functions_group, name,
623						&pci_epf_group_type);
624	if (IS_ERR(group))
625		pr_err("failed to register configfs group for %s function\n",
626		       name);
627
628	return group;
629}
630EXPORT_SYMBOL(pci_ep_cfs_add_epf_group);
631
632void pci_ep_cfs_remove_epf_group(struct config_group *group)
633{
634	if (IS_ERR_OR_NULL(group))
635		return;
636
637	configfs_unregister_default_group(group);
638}
639EXPORT_SYMBOL(pci_ep_cfs_remove_epf_group);
640
641static const struct config_item_type pci_functions_type = {
642	.ct_owner	= THIS_MODULE,
643};
644
645static const struct config_item_type pci_controllers_type = {
646	.ct_owner	= THIS_MODULE,
647};
648
649static const struct config_item_type pci_ep_type = {
650	.ct_owner	= THIS_MODULE,
651};
652
653static struct configfs_subsystem pci_ep_cfs_subsys = {
654	.su_group = {
655		.cg_item = {
656			.ci_namebuf = "pci_ep",
657			.ci_type = &pci_ep_type,
658		},
659	},
660	.su_mutex = __MUTEX_INITIALIZER(pci_ep_cfs_subsys.su_mutex),
661};
662
663static int __init pci_ep_cfs_init(void)
664{
665	int ret;
666	struct config_group *root = &pci_ep_cfs_subsys.su_group;
667
668	config_group_init(root);
669
670	ret = configfs_register_subsystem(&pci_ep_cfs_subsys);
671	if (ret) {
672		pr_err("Error %d while registering subsystem %s\n",
673		       ret, root->cg_item.ci_namebuf);
674		goto err;
675	}
676
677	functions_group = configfs_register_default_group(root, "functions",
678							  &pci_functions_type);
679	if (IS_ERR(functions_group)) {
680		ret = PTR_ERR(functions_group);
681		pr_err("Error %d while registering functions group\n",
682		       ret);
683		goto err_functions_group;
684	}
685
686	controllers_group =
687		configfs_register_default_group(root, "controllers",
688						&pci_controllers_type);
689	if (IS_ERR(controllers_group)) {
690		ret = PTR_ERR(controllers_group);
691		pr_err("Error %d while registering controllers group\n",
692		       ret);
693		goto err_controllers_group;
694	}
695
696	return 0;
697
698err_controllers_group:
699	configfs_unregister_default_group(functions_group);
700
701err_functions_group:
702	configfs_unregister_subsystem(&pci_ep_cfs_subsys);
703
704err:
705	return ret;
706}
707module_init(pci_ep_cfs_init);
708
709static void __exit pci_ep_cfs_exit(void)
710{
711	configfs_unregister_default_group(controllers_group);
712	configfs_unregister_default_group(functions_group);
713	configfs_unregister_subsystem(&pci_ep_cfs_subsys);
714}
715module_exit(pci_ep_cfs_exit);
716
717MODULE_DESCRIPTION("PCI EP CONFIGFS");
718MODULE_AUTHOR("Kishon Vijay Abraham I <kishon@ti.com>");
719MODULE_LICENSE("GPL v2");