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 | |
39 | struct component; |
40 | |
41 | struct 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 | |
50 | struct component_match { |
51 | size_t alloc; |
52 | size_t num; |
53 | struct component_match_array *compare; |
54 | }; |
55 | |
56 | struct 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 | |
65 | struct 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 | |
75 | static DEFINE_MUTEX(component_mutex); |
76 | static LIST_HEAD(component_list); |
77 | static LIST_HEAD(aggregate_devices); |
78 | |
79 | #ifdef CONFIG_DEBUG_FS |
80 | |
81 | static struct dentry *component_debugfs_dir; |
82 | |
83 | static 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(m: s, fmt: "%-40s %20s\n" , "aggregate_device name" , "status" ); |
91 | seq_puts(m: s, s: "-------------------------------------------------------------\n" ); |
92 | seq_printf(m: s, fmt: "%-40s %20s\n\n" , |
93 | dev_name(dev: m->parent), m->bound ? "bound" : "not bound" ); |
94 | |
95 | seq_printf(m: s, fmt: "%-40s %20s\n" , "device name" , "status" ); |
96 | seq_puts(m: s, s: "-------------------------------------------------------------\n" ); |
97 | for (i = 0; i < match->num; i++) { |
98 | struct component *component = match->compare[i].component; |
99 | |
100 | seq_printf(m: s, fmt: "%-40s %20s\n" , |
101 | component ? dev_name(dev: component->dev) : "(unknown)" , |
102 | component ? (component->bound ? "bound" : "not bound" ) : "not registered" ); |
103 | } |
104 | mutex_unlock(lock: &component_mutex); |
105 | |
106 | return 0; |
107 | } |
108 | |
109 | DEFINE_SHOW_ATTRIBUTE(component_devices); |
110 | |
111 | static int __init component_debug_init(void) |
112 | { |
113 | component_debugfs_dir = debugfs_create_dir(name: "device_component" , NULL); |
114 | |
115 | return 0; |
116 | } |
117 | |
118 | core_initcall(component_debug_init); |
119 | |
120 | static void component_debugfs_add(struct aggregate_device *m) |
121 | { |
122 | debugfs_create_file(name: dev_name(dev: m->parent), mode: 0444, parent: component_debugfs_dir, data: m, |
123 | fops: &component_devices_fops); |
124 | } |
125 | |
126 | static void component_debugfs_del(struct aggregate_device *m) |
127 | { |
128 | debugfs_lookup_and_remove(name: dev_name(dev: m->parent), parent: component_debugfs_dir); |
129 | } |
130 | |
131 | #else |
132 | |
133 | static void component_debugfs_add(struct aggregate_device *m) |
134 | { } |
135 | |
136 | static void component_debugfs_del(struct aggregate_device *m) |
137 | { } |
138 | |
139 | #endif |
140 | |
141 | static 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 | |
153 | static 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 | |
173 | static 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 */ |
210 | static 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 | */ |
227 | static 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(dev: adev->parent, id: 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(dev: 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(dev: adev->parent, NULL); |
258 | adev->bound = true; |
259 | return 1; |
260 | } |
261 | |
262 | static 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 | |
278 | static void take_down_aggregate_device(struct aggregate_device *adev) |
279 | { |
280 | if (adev->bound) { |
281 | adev->ops->unbind(adev->parent); |
282 | devres_release_group(dev: adev->parent, id: 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 | */ |
296 | int component_compare_of(struct device *dev, void *data) |
297 | { |
298 | return device_match_of_node(dev, np: data); |
299 | } |
300 | EXPORT_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 | */ |
309 | void component_release_of(struct device *dev, void *data) |
310 | { |
311 | of_node_put(node: data); |
312 | } |
313 | EXPORT_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 | */ |
323 | int component_compare_dev(struct device *dev, void *data) |
324 | { |
325 | return dev == data; |
326 | } |
327 | EXPORT_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 | */ |
338 | int component_compare_dev_name(struct device *dev, void *data) |
339 | { |
340 | return device_match_name(dev, name: data); |
341 | } |
342 | EXPORT_SYMBOL_GPL(component_compare_dev_name); |
343 | |
344 | static 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(objp: match->compare); |
357 | } |
358 | |
359 | static 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(n: num, size: 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(objp: match->compare); |
374 | } |
375 | match->compare = new; |
376 | match->alloc = num; |
377 | |
378 | return 0; |
379 | } |
380 | |
381 | static 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(ptr: 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(error: -ENOMEM); |
398 | return; |
399 | } |
400 | |
401 | devres_add(dev: parent, res: 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, num: new_size); |
411 | if (ret) { |
412 | *matchptr = ERR_PTR(error: 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 | */ |
445 | void 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 | } |
453 | EXPORT_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 | */ |
472 | void 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 | } |
479 | EXPORT_SYMBOL(component_match_add_typed); |
480 | |
481 | static void free_aggregate_device(struct aggregate_device *adev) |
482 | { |
483 | struct component_match *match = adev->match; |
484 | int i; |
485 | |
486 | component_debugfs_del(m: adev); |
487 | list_del(entry: &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(objp: 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 | */ |
512 | int 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, num: match->num); |
521 | if (ret) |
522 | return ret; |
523 | |
524 | adev = kzalloc(size: 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(m: adev); |
533 | /* Add to the list of available aggregate devices. */ |
534 | mutex_lock(&component_mutex); |
535 | list_add(new: &adev->node, head: &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(lock: &component_mutex); |
543 | |
544 | return ret < 0 ? ret : 0; |
545 | } |
546 | EXPORT_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 | */ |
557 | void 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(lock: &component_mutex); |
569 | } |
570 | EXPORT_SYMBOL_GPL(component_master_del); |
571 | |
572 | static void component_unbind(struct component *component, |
573 | struct aggregate_device *adev, void *data) |
574 | { |
575 | WARN_ON(!component->bound); |
576 | |
577 | if (component->ops && component->ops->unbind) |
578 | component->ops->unbind(component->dev, adev->parent, data); |
579 | component->bound = false; |
580 | |
581 | /* Release all resources claimed in the binding of this component */ |
582 | devres_release_group(dev: component->dev, id: component); |
583 | } |
584 | |
585 | /** |
586 | * component_unbind_all - unbind all components of an aggregate driver |
587 | * @parent: parent device of the aggregate driver |
588 | * @data: opaque pointer, passed to all components |
589 | * |
590 | * Unbinds all components of the aggregate device by passing @data to their |
591 | * &component_ops.unbind functions. Should be called from |
592 | * &component_master_ops.unbind. |
593 | */ |
594 | void component_unbind_all(struct device *parent, void *data) |
595 | { |
596 | struct aggregate_device *adev; |
597 | struct component *c; |
598 | size_t i; |
599 | |
600 | WARN_ON(!mutex_is_locked(&component_mutex)); |
601 | |
602 | adev = __aggregate_find(parent, NULL); |
603 | if (!adev) |
604 | return; |
605 | |
606 | /* Unbind components in reverse order */ |
607 | for (i = adev->match->num; i--; ) |
608 | if (!adev->match->compare[i].duplicate) { |
609 | c = adev->match->compare[i].component; |
610 | component_unbind(component: c, adev, data); |
611 | } |
612 | } |
613 | EXPORT_SYMBOL_GPL(component_unbind_all); |
614 | |
615 | static int component_bind(struct component *component, struct aggregate_device *adev, |
616 | void *data) |
617 | { |
618 | int ret; |
619 | |
620 | /* |
621 | * Each component initialises inside its own devres group. |
622 | * This allows us to roll-back a failed component without |
623 | * affecting anything else. |
624 | */ |
625 | if (!devres_open_group(dev: adev->parent, NULL, GFP_KERNEL)) |
626 | return -ENOMEM; |
627 | |
628 | /* |
629 | * Also open a group for the device itself: this allows us |
630 | * to release the resources claimed against the sub-device |
631 | * at the appropriate moment. |
632 | */ |
633 | if (!devres_open_group(dev: component->dev, id: component, GFP_KERNEL)) { |
634 | devres_release_group(dev: adev->parent, NULL); |
635 | return -ENOMEM; |
636 | } |
637 | |
638 | dev_dbg(adev->parent, "binding %s (ops %ps)\n" , |
639 | dev_name(component->dev), component->ops); |
640 | |
641 | ret = component->ops->bind(component->dev, adev->parent, data); |
642 | if (!ret) { |
643 | component->bound = true; |
644 | |
645 | /* |
646 | * Close the component device's group so that resources |
647 | * allocated in the binding are encapsulated for removal |
648 | * at unbind. Remove the group on the DRM device as we |
649 | * can clean those resources up independently. |
650 | */ |
651 | devres_close_group(dev: component->dev, NULL); |
652 | devres_remove_group(dev: adev->parent, NULL); |
653 | |
654 | dev_info(adev->parent, "bound %s (ops %ps)\n" , |
655 | dev_name(component->dev), component->ops); |
656 | } else { |
657 | devres_release_group(dev: component->dev, NULL); |
658 | devres_release_group(dev: adev->parent, NULL); |
659 | |
660 | if (ret != -EPROBE_DEFER) |
661 | dev_err(adev->parent, "failed to bind %s (ops %ps): %d\n" , |
662 | dev_name(component->dev), component->ops, ret); |
663 | } |
664 | |
665 | return ret; |
666 | } |
667 | |
668 | /** |
669 | * component_bind_all - bind all components of an aggregate driver |
670 | * @parent: parent device of the aggregate driver |
671 | * @data: opaque pointer, passed to all components |
672 | * |
673 | * Binds all components of the aggregate @dev by passing @data to their |
674 | * &component_ops.bind functions. Should be called from |
675 | * &component_master_ops.bind. |
676 | */ |
677 | int component_bind_all(struct device *parent, void *data) |
678 | { |
679 | struct aggregate_device *adev; |
680 | struct component *c; |
681 | size_t i; |
682 | int ret = 0; |
683 | |
684 | WARN_ON(!mutex_is_locked(&component_mutex)); |
685 | |
686 | adev = __aggregate_find(parent, NULL); |
687 | if (!adev) |
688 | return -EINVAL; |
689 | |
690 | /* Bind components in match order */ |
691 | for (i = 0; i < adev->match->num; i++) |
692 | if (!adev->match->compare[i].duplicate) { |
693 | c = adev->match->compare[i].component; |
694 | ret = component_bind(component: c, adev, data); |
695 | if (ret) |
696 | break; |
697 | } |
698 | |
699 | if (ret != 0) { |
700 | for (; i > 0; i--) |
701 | if (!adev->match->compare[i - 1].duplicate) { |
702 | c = adev->match->compare[i - 1].component; |
703 | component_unbind(component: c, adev, data); |
704 | } |
705 | } |
706 | |
707 | return ret; |
708 | } |
709 | EXPORT_SYMBOL_GPL(component_bind_all); |
710 | |
711 | static int __component_add(struct device *dev, const struct component_ops *ops, |
712 | int subcomponent) |
713 | { |
714 | struct component *component; |
715 | int ret; |
716 | |
717 | component = kzalloc(size: sizeof(*component), GFP_KERNEL); |
718 | if (!component) |
719 | return -ENOMEM; |
720 | |
721 | component->ops = ops; |
722 | component->dev = dev; |
723 | component->subcomponent = subcomponent; |
724 | |
725 | dev_dbg(dev, "adding component (ops %ps)\n" , ops); |
726 | |
727 | mutex_lock(&component_mutex); |
728 | list_add_tail(new: &component->node, head: &component_list); |
729 | |
730 | ret = try_to_bring_up_masters(component); |
731 | if (ret < 0) { |
732 | if (component->adev) |
733 | remove_component(adev: component->adev, c: component); |
734 | list_del(entry: &component->node); |
735 | |
736 | kfree(objp: component); |
737 | } |
738 | mutex_unlock(lock: &component_mutex); |
739 | |
740 | return ret < 0 ? ret : 0; |
741 | } |
742 | |
743 | /** |
744 | * component_add_typed - register a component |
745 | * @dev: component device |
746 | * @ops: component callbacks |
747 | * @subcomponent: nonzero identifier for subcomponents |
748 | * |
749 | * Register a new component for @dev. Functions in @ops will be call when the |
750 | * aggregate driver is ready to bind the overall driver by calling |
751 | * component_bind_all(). See also &struct component_ops. |
752 | * |
753 | * @subcomponent must be nonzero and is used to differentiate between multiple |
754 | * components registerd on the same device @dev. These components are match |
755 | * using component_match_add_typed(). |
756 | * |
757 | * The component needs to be unregistered at driver unload/disconnect by |
758 | * calling component_del(). |
759 | * |
760 | * See also component_add(). |
761 | */ |
762 | int component_add_typed(struct device *dev, const struct component_ops *ops, |
763 | int subcomponent) |
764 | { |
765 | if (WARN_ON(subcomponent == 0)) |
766 | return -EINVAL; |
767 | |
768 | return __component_add(dev, ops, subcomponent); |
769 | } |
770 | EXPORT_SYMBOL_GPL(component_add_typed); |
771 | |
772 | /** |
773 | * component_add - register a component |
774 | * @dev: component device |
775 | * @ops: component callbacks |
776 | * |
777 | * Register a new component for @dev. Functions in @ops will be called when the |
778 | * aggregate driver is ready to bind the overall driver by calling |
779 | * component_bind_all(). See also &struct component_ops. |
780 | * |
781 | * The component needs to be unregistered at driver unload/disconnect by |
782 | * calling component_del(). |
783 | * |
784 | * See also component_add_typed() for a variant that allows multipled different |
785 | * components on the same device. |
786 | */ |
787 | int component_add(struct device *dev, const struct component_ops *ops) |
788 | { |
789 | return __component_add(dev, ops, subcomponent: 0); |
790 | } |
791 | EXPORT_SYMBOL_GPL(component_add); |
792 | |
793 | /** |
794 | * component_del - unregister a component |
795 | * @dev: component device |
796 | * @ops: component callbacks |
797 | * |
798 | * Unregister a component added with component_add(). If the component is bound |
799 | * into an aggregate driver, this will force the entire aggregate driver, including |
800 | * all its components, to be unbound. |
801 | */ |
802 | void component_del(struct device *dev, const struct component_ops *ops) |
803 | { |
804 | struct component *c, *component = NULL; |
805 | |
806 | mutex_lock(&component_mutex); |
807 | list_for_each_entry(c, &component_list, node) |
808 | if (c->dev == dev && c->ops == ops) { |
809 | list_del(entry: &c->node); |
810 | component = c; |
811 | break; |
812 | } |
813 | |
814 | if (component && component->adev) { |
815 | take_down_aggregate_device(adev: component->adev); |
816 | remove_component(adev: component->adev, c: component); |
817 | } |
818 | |
819 | mutex_unlock(lock: &component_mutex); |
820 | |
821 | WARN_ON(!component); |
822 | kfree(objp: component); |
823 | } |
824 | EXPORT_SYMBOL_GPL(component_del); |
825 | |