xref: /openbmc/u-boot/drivers/core/uclass.c (revision 2399e401)
1 /*
2  * Copyright (c) 2013 Google, Inc
3  *
4  * (C) Copyright 2012
5  * Pavel Herrmann <morpheus.ibis@gmail.com>
6  *
7  * SPDX-License-Identifier:	GPL-2.0+
8  */
9 
10 #include <common.h>
11 #include <errno.h>
12 #include <malloc.h>
13 #include <dm/device.h>
14 #include <dm/device-internal.h>
15 #include <dm/lists.h>
16 #include <dm/uclass.h>
17 #include <dm/uclass-internal.h>
18 #include <dm/util.h>
19 
20 DECLARE_GLOBAL_DATA_PTR;
21 
22 struct uclass *uclass_find(enum uclass_id key)
23 {
24 	struct uclass *uc;
25 
26 	if (!gd->dm_root)
27 		return NULL;
28 	/*
29 	 * TODO(sjg@chromium.org): Optimise this, perhaps moving the found
30 	 * node to the start of the list, or creating a linear array mapping
31 	 * id to node.
32 	 */
33 	list_for_each_entry(uc, &gd->uclass_root, sibling_node) {
34 		if (uc->uc_drv->id == key)
35 			return uc;
36 	}
37 
38 	return NULL;
39 }
40 
41 /**
42  * uclass_add() - Create new uclass in list
43  * @id: Id number to create
44  * @ucp: Returns pointer to uclass, or NULL on error
45  * @return 0 on success, -ve on error
46  *
47  * The new uclass is added to the list. There must be only one uclass for
48  * each id.
49  */
50 static int uclass_add(enum uclass_id id, struct uclass **ucp)
51 {
52 	struct uclass_driver *uc_drv;
53 	struct uclass *uc;
54 	int ret;
55 
56 	*ucp = NULL;
57 	uc_drv = lists_uclass_lookup(id);
58 	if (!uc_drv) {
59 		debug("Cannot find uclass for id %d: please add the UCLASS_DRIVER() declaration for this UCLASS_... id\n",
60 		      id);
61 		/*
62 		 * Use a strange error to make this case easier to find. When
63 		 * a uclass is not available it can prevent driver model from
64 		 * starting up and this failure is otherwise hard to debug.
65 		 */
66 		return -EPFNOSUPPORT;
67 	}
68 	uc = calloc(1, sizeof(*uc));
69 	if (!uc)
70 		return -ENOMEM;
71 	if (uc_drv->priv_auto_alloc_size) {
72 		uc->priv = calloc(1, uc_drv->priv_auto_alloc_size);
73 		if (!uc->priv) {
74 			ret = -ENOMEM;
75 			goto fail_mem;
76 		}
77 	}
78 	uc->uc_drv = uc_drv;
79 	INIT_LIST_HEAD(&uc->sibling_node);
80 	INIT_LIST_HEAD(&uc->dev_head);
81 	list_add(&uc->sibling_node, &DM_UCLASS_ROOT_NON_CONST);
82 
83 	if (uc_drv->init) {
84 		ret = uc_drv->init(uc);
85 		if (ret)
86 			goto fail;
87 	}
88 
89 	*ucp = uc;
90 
91 	return 0;
92 fail:
93 	if (uc_drv->priv_auto_alloc_size) {
94 		free(uc->priv);
95 		uc->priv = NULL;
96 	}
97 	list_del(&uc->sibling_node);
98 fail_mem:
99 	free(uc);
100 
101 	return ret;
102 }
103 
104 int uclass_destroy(struct uclass *uc)
105 {
106 	struct uclass_driver *uc_drv;
107 	struct udevice *dev;
108 	int ret;
109 
110 	/*
111 	 * We cannot use list_for_each_entry_safe() here. If a device in this
112 	 * uclass has a child device also in this uclass, it will be also be
113 	 * unbound (by the recursion in the call to device_unbind() below).
114 	 * We can loop until the list is empty.
115 	 */
116 	while (!list_empty(&uc->dev_head)) {
117 		dev = list_first_entry(&uc->dev_head, struct udevice,
118 				       uclass_node);
119 		ret = device_remove(dev);
120 		if (ret)
121 			return ret;
122 		ret = device_unbind(dev);
123 		if (ret)
124 			return ret;
125 	}
126 
127 	uc_drv = uc->uc_drv;
128 	if (uc_drv->destroy)
129 		uc_drv->destroy(uc);
130 	list_del(&uc->sibling_node);
131 	if (uc_drv->priv_auto_alloc_size)
132 		free(uc->priv);
133 	free(uc);
134 
135 	return 0;
136 }
137 
138 int uclass_get(enum uclass_id id, struct uclass **ucp)
139 {
140 	struct uclass *uc;
141 
142 	*ucp = NULL;
143 	uc = uclass_find(id);
144 	if (!uc)
145 		return uclass_add(id, ucp);
146 	*ucp = uc;
147 
148 	return 0;
149 }
150 
151 const char *uclass_get_name(enum uclass_id id)
152 {
153 	struct uclass *uc;
154 
155 	if (uclass_get(id, &uc))
156 		return NULL;
157 	return uc->uc_drv->name;
158 }
159 
160 int uclass_find_device(enum uclass_id id, int index, struct udevice **devp)
161 {
162 	struct uclass *uc;
163 	struct udevice *dev;
164 	int ret;
165 
166 	*devp = NULL;
167 	ret = uclass_get(id, &uc);
168 	if (ret)
169 		return ret;
170 	if (list_empty(&uc->dev_head))
171 		return -ENODEV;
172 
173 	list_for_each_entry(dev, &uc->dev_head, uclass_node) {
174 		if (!index--) {
175 			*devp = dev;
176 			return 0;
177 		}
178 	}
179 
180 	return -ENODEV;
181 }
182 
183 int uclass_find_first_device(enum uclass_id id, struct udevice **devp)
184 {
185 	struct uclass *uc;
186 	int ret;
187 
188 	*devp = NULL;
189 	ret = uclass_get(id, &uc);
190 	if (ret)
191 		return ret;
192 	if (list_empty(&uc->dev_head))
193 		return 0;
194 
195 	*devp = list_first_entry(&uc->dev_head, struct udevice, uclass_node);
196 
197 	return 0;
198 }
199 
200 int uclass_find_next_device(struct udevice **devp)
201 {
202 	struct udevice *dev = *devp;
203 
204 	*devp = NULL;
205 	if (list_is_last(&dev->uclass_node, &dev->uclass->dev_head))
206 		return 0;
207 
208 	*devp = list_entry(dev->uclass_node.next, struct udevice, uclass_node);
209 
210 	return 0;
211 }
212 
213 int uclass_find_device_by_name(enum uclass_id id, const char *name,
214 			       struct udevice **devp)
215 {
216 	struct uclass *uc;
217 	struct udevice *dev;
218 	int ret;
219 
220 	*devp = NULL;
221 	if (!name)
222 		return -EINVAL;
223 	ret = uclass_get(id, &uc);
224 	if (ret)
225 		return ret;
226 
227 	list_for_each_entry(dev, &uc->dev_head, uclass_node) {
228 		if (!strncmp(dev->name, name, strlen(name))) {
229 			*devp = dev;
230 			return 0;
231 		}
232 	}
233 
234 	return -ENODEV;
235 }
236 
237 int uclass_find_device_by_seq(enum uclass_id id, int seq_or_req_seq,
238 			      bool find_req_seq, struct udevice **devp)
239 {
240 	struct uclass *uc;
241 	struct udevice *dev;
242 	int ret;
243 
244 	*devp = NULL;
245 	debug("%s: %d %d\n", __func__, find_req_seq, seq_or_req_seq);
246 	if (seq_or_req_seq == -1)
247 		return -ENODEV;
248 	ret = uclass_get(id, &uc);
249 	if (ret)
250 		return ret;
251 
252 	list_for_each_entry(dev, &uc->dev_head, uclass_node) {
253 		debug("   - %d %d\n", dev->req_seq, dev->seq);
254 		if ((find_req_seq ? dev->req_seq : dev->seq) ==
255 				seq_or_req_seq) {
256 			*devp = dev;
257 			debug("   - found\n");
258 			return 0;
259 		}
260 	}
261 	debug("   - not found\n");
262 
263 	return -ENODEV;
264 }
265 
266 int uclass_find_device_by_of_offset(enum uclass_id id, int node,
267 				    struct udevice **devp)
268 {
269 	struct uclass *uc;
270 	struct udevice *dev;
271 	int ret;
272 
273 	*devp = NULL;
274 	if (node < 0)
275 		return -ENODEV;
276 	ret = uclass_get(id, &uc);
277 	if (ret)
278 		return ret;
279 
280 	list_for_each_entry(dev, &uc->dev_head, uclass_node) {
281 		if (dev_of_offset(dev) == node) {
282 			*devp = dev;
283 			return 0;
284 		}
285 	}
286 
287 	return -ENODEV;
288 }
289 
290 #if CONFIG_IS_ENABLED(OF_CONTROL)
291 static int uclass_find_device_by_phandle(enum uclass_id id,
292 					 struct udevice *parent,
293 					 const char *name,
294 					 struct udevice **devp)
295 {
296 	struct udevice *dev;
297 	struct uclass *uc;
298 	int find_phandle;
299 	int ret;
300 
301 	*devp = NULL;
302 	find_phandle = fdtdec_get_int(gd->fdt_blob, dev_of_offset(parent), name,
303 				      -1);
304 	if (find_phandle <= 0)
305 		return -ENOENT;
306 	ret = uclass_get(id, &uc);
307 	if (ret)
308 		return ret;
309 
310 	list_for_each_entry(dev, &uc->dev_head, uclass_node) {
311 		uint phandle;
312 
313 		phandle = fdt_get_phandle(gd->fdt_blob, dev_of_offset(dev));
314 
315 		if (phandle == find_phandle) {
316 			*devp = dev;
317 			return 0;
318 		}
319 	}
320 
321 	return -ENODEV;
322 }
323 #endif
324 
325 int uclass_get_device_by_driver(enum uclass_id id,
326 				const struct driver *find_drv,
327 				struct udevice **devp)
328 {
329 	struct udevice *dev;
330 	struct uclass *uc;
331 	int ret;
332 
333 	ret = uclass_get(id, &uc);
334 	if (ret)
335 		return ret;
336 
337 	list_for_each_entry(dev, &uc->dev_head, uclass_node) {
338 		if (dev->driver == find_drv)
339 			return uclass_get_device_tail(dev, 0, devp);
340 	}
341 
342 	return -ENODEV;
343 }
344 
345 int uclass_get_device_tail(struct udevice *dev, int ret,
346 				  struct udevice **devp)
347 {
348 	if (ret)
349 		return ret;
350 
351 	assert(dev);
352 	ret = device_probe(dev);
353 	if (ret)
354 		return ret;
355 
356 	*devp = dev;
357 
358 	return 0;
359 }
360 
361 int uclass_get_device(enum uclass_id id, int index, struct udevice **devp)
362 {
363 	struct udevice *dev;
364 	int ret;
365 
366 	*devp = NULL;
367 	ret = uclass_find_device(id, index, &dev);
368 	return uclass_get_device_tail(dev, ret, devp);
369 }
370 
371 int uclass_get_device_by_name(enum uclass_id id, const char *name,
372 			      struct udevice **devp)
373 {
374 	struct udevice *dev;
375 	int ret;
376 
377 	*devp = NULL;
378 	ret = uclass_find_device_by_name(id, name, &dev);
379 	return uclass_get_device_tail(dev, ret, devp);
380 }
381 
382 int uclass_get_device_by_seq(enum uclass_id id, int seq, struct udevice **devp)
383 {
384 	struct udevice *dev;
385 	int ret;
386 
387 	*devp = NULL;
388 	ret = uclass_find_device_by_seq(id, seq, false, &dev);
389 	if (ret == -ENODEV) {
390 		/*
391 		 * We didn't find it in probed devices. See if there is one
392 		 * that will request this seq if probed.
393 		 */
394 		ret = uclass_find_device_by_seq(id, seq, true, &dev);
395 	}
396 	return uclass_get_device_tail(dev, ret, devp);
397 }
398 
399 int uclass_get_device_by_of_offset(enum uclass_id id, int node,
400 				   struct udevice **devp)
401 {
402 	struct udevice *dev;
403 	int ret;
404 
405 	*devp = NULL;
406 	ret = uclass_find_device_by_of_offset(id, node, &dev);
407 	return uclass_get_device_tail(dev, ret, devp);
408 }
409 
410 #if CONFIG_IS_ENABLED(OF_CONTROL)
411 int uclass_get_device_by_phandle(enum uclass_id id, struct udevice *parent,
412 				 const char *name, struct udevice **devp)
413 {
414 	struct udevice *dev;
415 	int ret;
416 
417 	*devp = NULL;
418 	ret = uclass_find_device_by_phandle(id, parent, name, &dev);
419 	return uclass_get_device_tail(dev, ret, devp);
420 }
421 #endif
422 
423 int uclass_first_device(enum uclass_id id, struct udevice **devp)
424 {
425 	struct udevice *dev;
426 	int ret;
427 
428 	*devp = NULL;
429 	ret = uclass_find_first_device(id, &dev);
430 	if (!dev)
431 		return 0;
432 	return uclass_get_device_tail(dev, ret, devp);
433 }
434 
435 int uclass_first_device_err(enum uclass_id id, struct udevice **devp)
436 {
437 	int ret;
438 
439 	ret = uclass_first_device(id, devp);
440 	if (ret)
441 		return ret;
442 	else if (!*devp)
443 		return -ENODEV;
444 
445 	return 0;
446 }
447 
448 int uclass_next_device(struct udevice **devp)
449 {
450 	struct udevice *dev = *devp;
451 	int ret;
452 
453 	*devp = NULL;
454 	ret = uclass_find_next_device(&dev);
455 	if (!dev)
456 		return 0;
457 	return uclass_get_device_tail(dev, ret, devp);
458 }
459 
460 int uclass_bind_device(struct udevice *dev)
461 {
462 	struct uclass *uc;
463 	int ret;
464 
465 	uc = dev->uclass;
466 	list_add_tail(&dev->uclass_node, &uc->dev_head);
467 
468 	if (dev->parent) {
469 		struct uclass_driver *uc_drv = dev->parent->uclass->uc_drv;
470 
471 		if (uc_drv->child_post_bind) {
472 			ret = uc_drv->child_post_bind(dev);
473 			if (ret)
474 				goto err;
475 		}
476 	}
477 
478 	return 0;
479 err:
480 	/* There is no need to undo the parent's post_bind call */
481 	list_del(&dev->uclass_node);
482 
483 	return ret;
484 }
485 
486 #if CONFIG_IS_ENABLED(DM_DEVICE_REMOVE)
487 int uclass_unbind_device(struct udevice *dev)
488 {
489 	struct uclass *uc;
490 	int ret;
491 
492 	uc = dev->uclass;
493 	if (uc->uc_drv->pre_unbind) {
494 		ret = uc->uc_drv->pre_unbind(dev);
495 		if (ret)
496 			return ret;
497 	}
498 
499 	list_del(&dev->uclass_node);
500 	return 0;
501 }
502 #endif
503 
504 int uclass_resolve_seq(struct udevice *dev)
505 {
506 	struct udevice *dup;
507 	int seq;
508 	int ret;
509 
510 	assert(dev->seq == -1);
511 	ret = uclass_find_device_by_seq(dev->uclass->uc_drv->id, dev->req_seq,
512 					false, &dup);
513 	if (!ret) {
514 		dm_warn("Device '%s': seq %d is in use by '%s'\n",
515 			dev->name, dev->req_seq, dup->name);
516 	} else if (ret == -ENODEV) {
517 		/* Our requested sequence number is available */
518 		if (dev->req_seq != -1)
519 			return dev->req_seq;
520 	} else {
521 		return ret;
522 	}
523 
524 	for (seq = 0; seq < DM_MAX_SEQ; seq++) {
525 		ret = uclass_find_device_by_seq(dev->uclass->uc_drv->id, seq,
526 						false, &dup);
527 		if (ret == -ENODEV)
528 			break;
529 		if (ret)
530 			return ret;
531 	}
532 	return seq;
533 }
534 
535 int uclass_pre_probe_device(struct udevice *dev)
536 {
537 	struct uclass_driver *uc_drv;
538 	int ret;
539 
540 	uc_drv = dev->uclass->uc_drv;
541 	if (uc_drv->pre_probe) {
542 		ret = uc_drv->pre_probe(dev);
543 		if (ret)
544 			return ret;
545 	}
546 
547 	if (!dev->parent)
548 		return 0;
549 	uc_drv = dev->parent->uclass->uc_drv;
550 	if (uc_drv->child_pre_probe)
551 		return uc_drv->child_pre_probe(dev);
552 
553 	return 0;
554 }
555 
556 int uclass_post_probe_device(struct udevice *dev)
557 {
558 	struct uclass_driver *uc_drv = dev->uclass->uc_drv;
559 
560 	if (uc_drv->post_probe)
561 		return uc_drv->post_probe(dev);
562 
563 	return 0;
564 }
565 
566 #if CONFIG_IS_ENABLED(DM_DEVICE_REMOVE)
567 int uclass_pre_remove_device(struct udevice *dev)
568 {
569 	struct uclass *uc;
570 	int ret;
571 
572 	uc = dev->uclass;
573 	if (uc->uc_drv->pre_remove) {
574 		ret = uc->uc_drv->pre_remove(dev);
575 		if (ret)
576 			return ret;
577 	}
578 
579 	return 0;
580 }
581 #endif
582