component.c

  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Componentized device handling.
  4 */
  5#include <linux/component.h>
  6#include <linux/device.h>
  7#include <linux/list.h>
  8#include <linux/mutex.h>
  9#include <linux/of.h>
 10#include <linux/slab.h>
 11#include <linux/debugfs.h>
 12
 13/**
 14 * DOC: overview
 15 *
 16 * The component helper allows drivers to collect a pile of sub-devices,
 17 * including their bound drivers, into an aggregate driver. Various subsystems
 18 * already provide functions to get hold of such components, e.g.
 19 * of_clk_get_by_name(). The component helper can be used when such a
 20 * subsystem-specific way to find a device is not available: The component
 21 * helper fills the niche of aggregate drivers for specific hardware, where
 22 * further standardization into a subsystem would not be practical. The common
 23 * example is when a logical device (e.g. a DRM display driver) is spread around
 24 * the SoC on various components (scanout engines, blending blocks, transcoders
 25 * for various outputs and so on).
 26 *
 27 * The component helper also doesn't solve runtime dependencies, e.g. for system
 28 * suspend and resume operations. See also :ref:`device links<device_link>`.
 29 *
 30 * Components are registered using component_add() and unregistered with
 31 * component_del(), usually from the driver's probe and disconnect functions.
 32 *
 33 * Aggregate drivers first assemble a component match list of what they need
 34 * using component_match_add(). This is then registered as an aggregate driver
 35 * using component_master_add_with_match(), and unregistered using
 36 * component_master_del().
 37 */
 38
 39struct component;
 40
 41struct component_match_array {
 42	void *data;
 43	int (*compare)(struct device *, void *);
 44	int (*compare_typed)(struct device *, int, void *);
 45	void (*release)(struct device *, void *);
 46	struct component *component;
 47	bool duplicate;
 48};
 49
 50struct component_match {
 51	size_t alloc;
 52	size_t num;
 53	struct component_match_array *compare;
 54};
 55
 56struct aggregate_device {
 57	struct list_head node;
 58	bool bound;
 59
 60	const struct component_master_ops *ops;
 61	struct device *parent;
 62	struct component_match *match;
 63};
 64
 65struct component {
 66	struct list_head node;
 67	struct aggregate_device *adev;
 68	bool bound;
 69
 70	const struct component_ops *ops;
 71	int subcomponent;
 72	struct device *dev;
 73};
 74
 75static DEFINE_MUTEX(component_mutex);
 76static LIST_HEAD(component_list);
 77static LIST_HEAD(aggregate_devices);
 78
 79#ifdef CONFIG_DEBUG_FS
 80
 81static struct dentry *component_debugfs_dir;
 82
 83static int component_devices_show(struct seq_file *s, void *data)
 84{
 85	struct aggregate_device *m = s->private;
 86	struct component_match *match = m->match;
 87	size_t i;
 88
 89	mutex_lock(&component_mutex);
 90	seq_printf(s, "%-50s %20s\n", "aggregate_device name", "status");
 91	seq_puts(s, "-----------------------------------------------------------------------\n");
 92	seq_printf(s, "%-50s %20s\n\n",
 93		   dev_name(m->parent), m->bound ? "bound" : "not bound");
 94
 95	seq_printf(s, "%-50s %20s\n", "device name", "status");
 96	seq_puts(s, "-----------------------------------------------------------------------\n");
 97	for (i = 0; i < match->num; i++) {
 98		struct component *component = match->compare[i].component;
 99
100		seq_printf(s, "%-50s %20s\n",
101			   component ? dev_name(component->dev) : "(unknown)",
102			   component ? (component->bound ? "bound" : "not bound") : "not registered");
103	}
104	mutex_unlock(&component_mutex);
105
106	return 0;
107}
108
109DEFINE_SHOW_ATTRIBUTE(component_devices);
110
111static int __init component_debug_init(void)
112{
113	component_debugfs_dir = debugfs_create_dir("device_component", NULL);
114
115	return 0;
116}
117
118core_initcall(component_debug_init);
119
120static void component_debugfs_add(struct aggregate_device *m)
121{
122	debugfs_create_file(dev_name(m->parent), 0444, component_debugfs_dir, m,
123			    &component_devices_fops);
124}
125
126static void component_debugfs_del(struct aggregate_device *m)
127{
128	debugfs_lookup_and_remove(dev_name(m->parent), component_debugfs_dir);
129}
130
131#else
132
133static void component_debugfs_add(struct aggregate_device *m)
134{ }
135
136static void component_debugfs_del(struct aggregate_device *m)
137{ }
138
139#endif
140
141static struct aggregate_device *__aggregate_find(struct device *parent,
142	const struct component_master_ops *ops)
143{
144	struct aggregate_device *m;
145
146	list_for_each_entry(m, &aggregate_devices, node)
147		if (m->parent == parent && (!ops || m->ops == ops))
148			return m;
149
150	return NULL;
151}
152
153static struct component *find_component(struct aggregate_device *adev,
154	struct component_match_array *mc)
155{
156	struct component *c;
157
158	list_for_each_entry(c, &component_list, node) {
159		if (c->adev && c->adev != adev)
160			continue;
161
162		if (mc->compare && mc->compare(c->dev, mc->data))
163			return c;
164
165		if (mc->compare_typed &&
166		    mc->compare_typed(c->dev, c->subcomponent, mc->data))
167			return c;
168	}
169
170	return NULL;
171}
172
173static int find_components(struct aggregate_device *adev)
174{
175	struct component_match *match = adev->match;
176	size_t i;
177	int ret = 0;
178
179	/*
180	 * Scan the array of match functions and attach
181	 * any components which are found to this adev.
182	 */
183	for (i = 0; i < match->num; i++) {
184		struct component_match_array *mc = &match->compare[i];
185		struct component *c;
186
187		dev_dbg(adev->parent, "Looking for component %zu\n", i);
188
189		if (match->compare[i].component)
190			continue;
191
192		c = find_component(adev, mc);
193		if (!c) {
194			ret = -ENXIO;
195			break;
196		}
197
198		dev_dbg(adev->parent, "found component %s, duplicate %u\n",
199			dev_name(c->dev), !!c->adev);
200
201		/* Attach this component to the adev */
202		match->compare[i].duplicate = !!c->adev;
203		match->compare[i].component = c;
204		c->adev = adev;
205	}
206	return ret;
207}
208
209/* Detach component from associated aggregate_device */
210static void remove_component(struct aggregate_device *adev, struct component *c)
211{
212	size_t i;
213
214	/* Detach the component from this adev. */
215	for (i = 0; i < adev->match->num; i++)
216		if (adev->match->compare[i].component == c)
217			adev->match->compare[i].component = NULL;
218}
219
220/*
221 * Try to bring up an aggregate device.  If component is NULL, we're interested
222 * in this aggregate device, otherwise it's a component which must be present
223 * to try and bring up the aggregate device.
224 *
225 * Returns 1 for successful bringup, 0 if not ready, or -ve errno.
226 */
227static int try_to_bring_up_aggregate_device(struct aggregate_device *adev,
228	struct component *component)
229{
230	int ret;
231
232	dev_dbg(adev->parent, "trying to bring up adev\n");
233
234	if (find_components(adev)) {
235		dev_dbg(adev->parent, "master has incomplete components\n");
236		return 0;
237	}
238
239	if (component && component->adev != adev) {
240		dev_dbg(adev->parent, "master is not for this component (%s)\n",
241			dev_name(component->dev));
242		return 0;
243	}
244
245	if (!devres_open_group(adev->parent, adev, GFP_KERNEL))
246		return -ENOMEM;
247
248	/* Found all components */
249	ret = adev->ops->bind(adev->parent);
250	if (ret < 0) {
251		devres_release_group(adev->parent, NULL);
252		if (ret != -EPROBE_DEFER)
253			dev_info(adev->parent, "adev bind failed: %d\n", ret);
254		return ret;
255	}
256
257	devres_close_group(adev->parent, NULL);
258	adev->bound = true;
259	return 1;
260}
261
262static int try_to_bring_up_masters(struct component *component)
263{
264	struct aggregate_device *adev;
265	int ret = 0;
266
267	list_for_each_entry(adev, &aggregate_devices, node) {
268		if (!adev->bound) {
269			ret = try_to_bring_up_aggregate_device(adev, component);
270			if (ret != 0)
271				break;
272		}
273	}
274
275	return ret;
276}
277
278static void take_down_aggregate_device(struct aggregate_device *adev)
279{
280	if (adev->bound) {
281		adev->ops->unbind(adev->parent);
282		devres_release_group(adev->parent, adev);
283		adev->bound = false;
284	}
285}
286
287/**
288 * component_compare_of - A common component compare function for of_node
289 * @dev: component device
290 * @data: @compare_data from component_match_add_release()
291 *
292 * A common compare function when compare_data is device of_node. e.g.
293 * component_match_add_release(masterdev, &match, component_release_of,
294 * component_compare_of, component_dev_of_node)
295 */
296int component_compare_of(struct device *dev, void *data)
297{
298	return device_match_of_node(dev, data);
299}
300EXPORT_SYMBOL_GPL(component_compare_of);
301
302/**
303 * component_release_of - A common component release function for of_node
304 * @dev: component device
305 * @data: @compare_data from component_match_add_release()
306 *
307 * About the example, Please see component_compare_of().
308 */
309void component_release_of(struct device *dev, void *data)
310{
311	of_node_put(data);
312}
313EXPORT_SYMBOL_GPL(component_release_of);
314
315/**
316 * component_compare_dev - A common component compare function for dev
317 * @dev: component device
318 * @data: @compare_data from component_match_add_release()
319 *
320 * A common compare function when compare_data is struce device. e.g.
321 * component_match_add(masterdev, &match, component_compare_dev, component_dev)
322 */
323int component_compare_dev(struct device *dev, void *data)
324{
325	return dev == data;
326}
327EXPORT_SYMBOL_GPL(component_compare_dev);
328
329/**
330 * component_compare_dev_name - A common component compare function for device name
331 * @dev: component device
332 * @data: @compare_data from component_match_add_release()
333 *
334 * A common compare function when compare_data is device name string. e.g.
335 * component_match_add(masterdev, &match, component_compare_dev_name,
336 * "component_dev_name")
337 */
338int component_compare_dev_name(struct device *dev, void *data)
339{
340	return device_match_name(dev, data);
341}
342EXPORT_SYMBOL_GPL(component_compare_dev_name);
343
344static void devm_component_match_release(struct device *parent, void *res)
345{
346	struct component_match *match = res;
347	unsigned int i;
348
349	for (i = 0; i < match->num; i++) {
350		struct component_match_array *mc = &match->compare[i];
351
352		if (mc->release)
353			mc->release(parent, mc->data);
354	}
355
356	kfree(match->compare);
357}
358
359static int component_match_realloc(struct component_match *match, size_t num)
360{
361	struct component_match_array *new;
362
363	if (match->alloc == num)
364		return 0;
365
366	new = kmalloc_array(num, sizeof(*new), GFP_KERNEL);
367	if (!new)
368		return -ENOMEM;
369
370	if (match->compare) {
371		memcpy(new, match->compare, sizeof(*new) *
372					    min(match->num, num));
373		kfree(match->compare);
374	}
375	match->compare = new;
376	match->alloc = num;
377
378	return 0;
379}
380
381static void __component_match_add(struct device *parent,
382	struct component_match **matchptr,
383	void (*release)(struct device *, void *),
384	int (*compare)(struct device *, void *),
385	int (*compare_typed)(struct device *, int, void *),
386	void *compare_data)
387{
388	struct component_match *match = *matchptr;
389
390	if (IS_ERR(match))
391		return;
392
393	if (!match) {
394		match = devres_alloc(devm_component_match_release,
395				     sizeof(*match), GFP_KERNEL);
396		if (!match) {
397			*matchptr = ERR_PTR(-ENOMEM);
398			return;
399		}
400
401		devres_add(parent, match);
402
403		*matchptr = match;
404	}
405
406	if (match->num == match->alloc) {
407		size_t new_size = match->alloc + 16;
408		int ret;
409
410		ret = component_match_realloc(match, new_size);
411		if (ret) {
412			*matchptr = ERR_PTR(ret);
413			return;
414		}
415	}
416
417	match->compare[match->num].compare = compare;
418	match->compare[match->num].compare_typed = compare_typed;
419	match->compare[match->num].release = release;
420	match->compare[match->num].data = compare_data;
421	match->compare[match->num].component = NULL;
422	match->num++;
423}
424
425/**
426 * component_match_add_release - add a component match entry with release callback
427 * @parent: parent device of the aggregate driver
428 * @matchptr: pointer to the list of component matches
429 * @release: release function for @compare_data
430 * @compare: compare function to match against all components
431 * @compare_data: opaque pointer passed to the @compare function
432 *
433 * Adds a new component match to the list stored in @matchptr, which the
434 * aggregate driver needs to function. The list of component matches pointed to
435 * by @matchptr must be initialized to NULL before adding the first match. This
436 * only matches against components added with component_add().
437 *
438 * The allocated match list in @matchptr is automatically released using devm
439 * actions, where upon @release will be called to free any references held by
440 * @compare_data, e.g. when @compare_data is a &device_node that must be
441 * released with of_node_put().
442 *
443 * See also component_match_add() and component_match_add_typed().
444 */
445void component_match_add_release(struct device *parent,
446	struct component_match **matchptr,
447	void (*release)(struct device *, void *),
448	int (*compare)(struct device *, void *), void *compare_data)
449{
450	__component_match_add(parent, matchptr, release, compare, NULL,
451			      compare_data);
452}
453EXPORT_SYMBOL(component_match_add_release);
454
455/**
456 * component_match_add_typed - add a component match entry for a typed component
457 * @parent: parent device of the aggregate driver
458 * @matchptr: pointer to the list of component matches
459 * @compare_typed: compare function to match against all typed components
460 * @compare_data: opaque pointer passed to the @compare function
461 *
462 * Adds a new component match to the list stored in @matchptr, which the
463 * aggregate driver needs to function. The list of component matches pointed to
464 * by @matchptr must be initialized to NULL before adding the first match. This
465 * only matches against components added with component_add_typed().
466 *
467 * The allocated match list in @matchptr is automatically released using devm
468 * actions.
469 *
470 * See also component_match_add_release() and component_match_add_typed().
471 */
472void component_match_add_typed(struct device *parent,
473	struct component_match **matchptr,
474	int (*compare_typed)(struct device *, int, void *), void *compare_data)
475{
476	__component_match_add(parent, matchptr, NULL, NULL, compare_typed,
477			      compare_data);
478}
479EXPORT_SYMBOL(component_match_add_typed);
480
481static void free_aggregate_device(struct aggregate_device *adev)
482{
483	struct component_match *match = adev->match;
484	int i;
485
486	component_debugfs_del(adev);
487	list_del(&adev->node);
488
489	if (match) {
490		for (i = 0; i < match->num; i++) {
491			struct component *c = match->compare[i].component;
492			if (c)
493				c->adev = NULL;
494		}
495	}
496
497	kfree(adev);
498}
499
500/**
501 * component_master_add_with_match - register an aggregate driver
502 * @parent: parent device of the aggregate driver
503 * @ops: callbacks for the aggregate driver
504 * @match: component match list for the aggregate driver
505 *
506 * Registers a new aggregate driver consisting of the components added to @match
507 * by calling one of the component_match_add() functions. Once all components in
508 * @match are available, it will be assembled by calling
509 * &component_master_ops.bind from @ops. Must be unregistered by calling
510 * component_master_del().
511 */
512int component_master_add_with_match(struct device *parent,
513	const struct component_master_ops *ops,
514	struct component_match *match)
515{
516	struct aggregate_device *adev;
517	int ret;
518
519	/* Reallocate the match array for its true size */
520	ret = component_match_realloc(match, match->num);
521	if (ret)
522		return ret;
523
524	adev = kzalloc(sizeof(*adev), GFP_KERNEL);
525	if (!adev)
526		return -ENOMEM;
527
528	adev->parent = parent;
529	adev->ops = ops;
530	adev->match = match;
531
532	component_debugfs_add(adev);
533	/* Add to the list of available aggregate devices. */
534	mutex_lock(&component_mutex);
535	list_add(&adev->node, &aggregate_devices);
536
537	ret = try_to_bring_up_aggregate_device(adev, NULL);
538
539	if (ret < 0)
540		free_aggregate_device(adev);
541
542	mutex_unlock(&component_mutex);
543
544	return ret < 0 ? ret : 0;
545}
546EXPORT_SYMBOL_GPL(component_master_add_with_match);
547
548/**
549 * component_master_del - unregister an aggregate driver
550 * @parent: parent device of the aggregate driver
551 * @ops: callbacks for the aggregate driver
552 *
553 * Unregisters an aggregate driver registered with
554 * component_master_add_with_match(). If necessary the aggregate driver is first
555 * disassembled by calling &component_master_ops.unbind from @ops.
556 */
557void component_master_del(struct device *parent,
558	const struct component_master_ops *ops)
559{
560	struct aggregate_device *adev;
561
562	mutex_lock(&component_mutex);
563	adev = __aggregate_find(parent, ops);
564	if (adev) {
565		take_down_aggregate_device(adev);
566		free_aggregate_device(adev);
567	}
568	mutex_unlock(&component_mutex);
569}
570EXPORT_SYMBOL_GPL(component_master_del);
571
572bool component_master_is_bound(struct device *parent,
573	const struct component_master_ops *ops)
574{
575	struct aggregate_device *adev;
576
577	guard(mutex)(&component_mutex);
578	adev = __aggregate_find(parent, ops);
579	if (!adev)
580		return 0;
581
582	return adev->bound;
583}
584EXPORT_SYMBOL_GPL(component_master_is_bound);
585
586static void component_unbind(struct component *component,
587	struct aggregate_device *adev, void *data)
588{
589	if (WARN_ON(!component->bound))
590		return;
591
592	dev_dbg(adev->parent, "unbinding %s component %p (ops %ps)\n",
593		dev_name(component->dev), component, component->ops);
594
595	if (component->ops && component->ops->unbind)
596		component->ops->unbind(component->dev, adev->parent, data);
597	component->bound = false;
598
599	/* Release all resources claimed in the binding of this component */
600	devres_release_group(component->dev, component);
601}
602
603/**
604 * component_unbind_all - unbind all components of an aggregate driver
605 * @parent: parent device of the aggregate driver
606 * @data: opaque pointer, passed to all components
607 *
608 * Unbinds all components of the aggregate device by passing @data to their
609 * &component_ops.unbind functions. Should be called from
610 * &component_master_ops.unbind.
611 */
612void component_unbind_all(struct device *parent, void *data)
613{
614	struct aggregate_device *adev;
615	struct component *c;
616	size_t i;
617
618	WARN_ON(!mutex_is_locked(&component_mutex));
619
620	adev = __aggregate_find(parent, NULL);
621	if (!adev)
622		return;
623
624	/* Unbind components in reverse order */
625	for (i = adev->match->num; i--; )
626		if (!adev->match->compare[i].duplicate) {
627			c = adev->match->compare[i].component;
628			component_unbind(c, adev, data);
629		}
630}
631EXPORT_SYMBOL_GPL(component_unbind_all);
632
633static int component_bind(struct component *component, struct aggregate_device *adev,
634	void *data)
635{
636	int ret;
637
638	/*
639	 * Each component initialises inside its own devres group.
640	 * This allows us to roll-back a failed component without
641	 * affecting anything else.
642	 */
643	if (!devres_open_group(adev->parent, NULL, GFP_KERNEL))
644		return -ENOMEM;
645
646	/*
647	 * Also open a group for the device itself: this allows us
648	 * to release the resources claimed against the sub-device
649	 * at the appropriate moment.
650	 */
651	if (!devres_open_group(component->dev, component, GFP_KERNEL)) {
652		devres_release_group(adev->parent, NULL);
653		return -ENOMEM;
654	}
655
656	dev_dbg(adev->parent, "binding %s (ops %ps)\n",
657		dev_name(component->dev), component->ops);
658
659	ret = component->ops->bind(component->dev, adev->parent, data);
660	if (!ret) {
661		component->bound = true;
662
663		/*
664		 * Close the component device's group so that resources
665		 * allocated in the binding are encapsulated for removal
666		 * at unbind.  Remove the group on the DRM device as we
667		 * can clean those resources up independently.
668		 */
669		devres_close_group(component->dev, NULL);
670		devres_remove_group(adev->parent, NULL);
671
672		dev_info(adev->parent, "bound %s (ops %ps)\n",
673			 dev_name(component->dev), component->ops);
674	} else {
675		devres_release_group(component->dev, NULL);
676		devres_release_group(adev->parent, NULL);
677
678		if (ret != -EPROBE_DEFER)
679			dev_err(adev->parent, "failed to bind %s (ops %ps): %d\n",
680				dev_name(component->dev), component->ops, ret);
681	}
682
683	return ret;
684}
685
686/**
687 * component_bind_all - bind all components of an aggregate driver
688 * @parent: parent device of the aggregate driver
689 * @data: opaque pointer, passed to all components
690 *
691 * Binds all components of the aggregate @dev by passing @data to their
692 * &component_ops.bind functions. Should be called from
693 * &component_master_ops.bind.
694 */
695int component_bind_all(struct device *parent, void *data)
696{
697	struct aggregate_device *adev;
698	struct component *c;
699	size_t i;
700	int ret = 0;
701
702	WARN_ON(!mutex_is_locked(&component_mutex));
703
704	adev = __aggregate_find(parent, NULL);
705	if (!adev)
706		return -EINVAL;
707
708	/* Bind components in match order */
709	for (i = 0; i < adev->match->num; i++)
710		if (!adev->match->compare[i].duplicate) {
711			c = adev->match->compare[i].component;
712			ret = component_bind(c, adev, data);
713			if (ret)
714				break;
715		}
716
717	if (ret != 0) {
718		for (; i > 0; i--)
719			if (!adev->match->compare[i - 1].duplicate) {
720				c = adev->match->compare[i - 1].component;
721				component_unbind(c, adev, data);
722			}
723	}
724
725	return ret;
726}
727EXPORT_SYMBOL_GPL(component_bind_all);
728
729static int __component_add(struct device *dev, const struct component_ops *ops,
730	int subcomponent)
731{
732	struct component *component;
733	int ret;
734
735	component = kzalloc(sizeof(*component), GFP_KERNEL);
736	if (!component)
737		return -ENOMEM;
738
739	component->ops = ops;
740	component->dev = dev;
741	component->subcomponent = subcomponent;
742
743	dev_dbg(dev, "adding component (ops %ps)\n", ops);
744
745	mutex_lock(&component_mutex);
746	list_add_tail(&component->node, &component_list);
747
748	ret = try_to_bring_up_masters(component);
749	if (ret < 0) {
750		if (component->adev)
751			remove_component(component->adev, component);
752		list_del(&component->node);
753
754		kfree(component);
755	}
756	mutex_unlock(&component_mutex);
757
758	return ret < 0 ? ret : 0;
759}
760
761/**
762 * component_add_typed - register a component
763 * @dev: component device
764 * @ops: component callbacks
765 * @subcomponent: nonzero identifier for subcomponents
766 *
767 * Register a new component for @dev. Functions in @ops will be call when the
768 * aggregate driver is ready to bind the overall driver by calling
769 * component_bind_all(). See also &struct component_ops.
770 *
771 * @subcomponent must be nonzero and is used to differentiate between multiple
772 * components registered on the same device @dev. These components are match
773 * using component_match_add_typed().
774 *
775 * The component needs to be unregistered at driver unload/disconnect by
776 * calling component_del().
777 *
778 * See also component_add().
779 */
780int component_add_typed(struct device *dev, const struct component_ops *ops,
781	int subcomponent)
782{
783	if (WARN_ON(subcomponent == 0))
784		return -EINVAL;
785
786	return __component_add(dev, ops, subcomponent);
787}
788EXPORT_SYMBOL_GPL(component_add_typed);
789
790/**
791 * component_add - register a component
792 * @dev: component device
793 * @ops: component callbacks
794 *
795 * Register a new component for @dev. Functions in @ops will be called when the
796 * aggregate driver is ready to bind the overall driver by calling
797 * component_bind_all(). See also &struct component_ops.
798 *
799 * The component needs to be unregistered at driver unload/disconnect by
800 * calling component_del().
801 *
802 * See also component_add_typed() for a variant that allows multiple different
803 * components on the same device.
804 */
805int component_add(struct device *dev, const struct component_ops *ops)
806{
807	return __component_add(dev, ops, 0);
808}
809EXPORT_SYMBOL_GPL(component_add);
810
811/**
812 * component_del - unregister a component
813 * @dev: component device
814 * @ops: component callbacks
815 *
816 * Unregister a component added with component_add(). If the component is bound
817 * into an aggregate driver, this will force the entire aggregate driver, including
818 * all its components, to be unbound.
819 */
820void component_del(struct device *dev, const struct component_ops *ops)
821{
822	struct component *c, *component = NULL;
823
824	mutex_lock(&component_mutex);
825	list_for_each_entry(c, &component_list, node)
826		if (c->dev == dev && c->ops == ops) {
827			list_del(&c->node);
828			component = c;
829			break;
830		}
831
832	if (component && component->adev) {
833		take_down_aggregate_device(component->adev);
834		remove_component(component->adev, component);
835	}
836
837	mutex_unlock(&component_mutex);
838
839	WARN_ON(!component);
840	kfree(component);
841}
842EXPORT_SYMBOL_GPL(component_del);