xref: /openbmc/u-boot/drivers/core/uclass.c (revision 4897d950)
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 int uclass_find_device(enum uclass_id id, int index, struct udevice **devp)
152 {
153 	struct uclass *uc;
154 	struct udevice *dev;
155 	int ret;
156 
157 	*devp = NULL;
158 	ret = uclass_get(id, &uc);
159 	if (ret)
160 		return ret;
161 	if (list_empty(&uc->dev_head))
162 		return -ENODEV;
163 
164 	list_for_each_entry(dev, &uc->dev_head, uclass_node) {
165 		if (!index--) {
166 			*devp = dev;
167 			return 0;
168 		}
169 	}
170 
171 	return -ENODEV;
172 }
173 
174 int uclass_find_first_device(enum uclass_id id, struct udevice **devp)
175 {
176 	struct uclass *uc;
177 	int ret;
178 
179 	*devp = NULL;
180 	ret = uclass_get(id, &uc);
181 	if (ret)
182 		return ret;
183 	if (list_empty(&uc->dev_head))
184 		return 0;
185 
186 	*devp = list_first_entry(&uc->dev_head, struct udevice, uclass_node);
187 
188 	return 0;
189 }
190 
191 int uclass_find_next_device(struct udevice **devp)
192 {
193 	struct udevice *dev = *devp;
194 
195 	*devp = NULL;
196 	if (list_is_last(&dev->uclass_node, &dev->uclass->dev_head))
197 		return 0;
198 
199 	*devp = list_entry(dev->uclass_node.next, struct udevice, uclass_node);
200 
201 	return 0;
202 }
203 
204 int uclass_find_device_by_name(enum uclass_id id, const char *name,
205 			       struct udevice **devp)
206 {
207 	struct uclass *uc;
208 	struct udevice *dev;
209 	int ret;
210 
211 	*devp = NULL;
212 	if (!name)
213 		return -EINVAL;
214 	ret = uclass_get(id, &uc);
215 	if (ret)
216 		return ret;
217 
218 	list_for_each_entry(dev, &uc->dev_head, uclass_node) {
219 		if (!strncmp(dev->name, name, strlen(name))) {
220 			*devp = dev;
221 			return 0;
222 		}
223 	}
224 
225 	return -ENODEV;
226 }
227 
228 int uclass_find_device_by_seq(enum uclass_id id, int seq_or_req_seq,
229 			      bool find_req_seq, struct udevice **devp)
230 {
231 	struct uclass *uc;
232 	struct udevice *dev;
233 	int ret;
234 
235 	*devp = NULL;
236 	debug("%s: %d %d\n", __func__, find_req_seq, seq_or_req_seq);
237 	if (seq_or_req_seq == -1)
238 		return -ENODEV;
239 	ret = uclass_get(id, &uc);
240 	if (ret)
241 		return ret;
242 
243 	list_for_each_entry(dev, &uc->dev_head, uclass_node) {
244 		debug("   - %d %d\n", dev->req_seq, dev->seq);
245 		if ((find_req_seq ? dev->req_seq : dev->seq) ==
246 				seq_or_req_seq) {
247 			*devp = dev;
248 			debug("   - found\n");
249 			return 0;
250 		}
251 	}
252 	debug("   - not found\n");
253 
254 	return -ENODEV;
255 }
256 
257 int uclass_find_device_by_of_offset(enum uclass_id id, int node,
258 				    struct udevice **devp)
259 {
260 	struct uclass *uc;
261 	struct udevice *dev;
262 	int ret;
263 
264 	*devp = NULL;
265 	if (node < 0)
266 		return -ENODEV;
267 	ret = uclass_get(id, &uc);
268 	if (ret)
269 		return ret;
270 
271 	list_for_each_entry(dev, &uc->dev_head, uclass_node) {
272 		if (dev->of_offset == node) {
273 			*devp = dev;
274 			return 0;
275 		}
276 	}
277 
278 	return -ENODEV;
279 }
280 
281 #if CONFIG_IS_ENABLED(OF_CONTROL)
282 static int uclass_find_device_by_phandle(enum uclass_id id,
283 					 struct udevice *parent,
284 					 const char *name,
285 					 struct udevice **devp)
286 {
287 	struct udevice *dev;
288 	struct uclass *uc;
289 	int find_phandle;
290 	int ret;
291 
292 	*devp = NULL;
293 	find_phandle = fdtdec_get_int(gd->fdt_blob, parent->of_offset, name,
294 				      -1);
295 	if (find_phandle <= 0)
296 		return -ENOENT;
297 	ret = uclass_get(id, &uc);
298 	if (ret)
299 		return ret;
300 
301 	list_for_each_entry(dev, &uc->dev_head, uclass_node) {
302 		uint phandle = fdt_get_phandle(gd->fdt_blob, dev->of_offset);
303 
304 		if (phandle == find_phandle) {
305 			*devp = dev;
306 			return 0;
307 		}
308 	}
309 
310 	return -ENODEV;
311 }
312 #endif
313 
314 int uclass_get_device_tail(struct udevice *dev, int ret,
315 				  struct udevice **devp)
316 {
317 	if (ret)
318 		return ret;
319 
320 	assert(dev);
321 	ret = device_probe(dev);
322 	if (ret)
323 		return ret;
324 
325 	*devp = dev;
326 
327 	return 0;
328 }
329 
330 int uclass_get_device(enum uclass_id id, int index, struct udevice **devp)
331 {
332 	struct udevice *dev;
333 	int ret;
334 
335 	*devp = NULL;
336 	ret = uclass_find_device(id, index, &dev);
337 	return uclass_get_device_tail(dev, ret, devp);
338 }
339 
340 int uclass_get_device_by_name(enum uclass_id id, const char *name,
341 			      struct udevice **devp)
342 {
343 	struct udevice *dev;
344 	int ret;
345 
346 	*devp = NULL;
347 	ret = uclass_find_device_by_name(id, name, &dev);
348 	return uclass_get_device_tail(dev, ret, devp);
349 }
350 
351 int uclass_get_device_by_seq(enum uclass_id id, int seq, struct udevice **devp)
352 {
353 	struct udevice *dev;
354 	int ret;
355 
356 	*devp = NULL;
357 	ret = uclass_find_device_by_seq(id, seq, false, &dev);
358 	if (ret == -ENODEV) {
359 		/*
360 		 * We didn't find it in probed devices. See if there is one
361 		 * that will request this seq if probed.
362 		 */
363 		ret = uclass_find_device_by_seq(id, seq, true, &dev);
364 	}
365 	return uclass_get_device_tail(dev, ret, devp);
366 }
367 
368 int uclass_get_device_by_of_offset(enum uclass_id id, int node,
369 				   struct udevice **devp)
370 {
371 	struct udevice *dev;
372 	int ret;
373 
374 	*devp = NULL;
375 	ret = uclass_find_device_by_of_offset(id, node, &dev);
376 	return uclass_get_device_tail(dev, ret, devp);
377 }
378 
379 #if CONFIG_IS_ENABLED(OF_CONTROL)
380 int uclass_get_device_by_phandle(enum uclass_id id, struct udevice *parent,
381 				 const char *name, struct udevice **devp)
382 {
383 	struct udevice *dev;
384 	int ret;
385 
386 	*devp = NULL;
387 	ret = uclass_find_device_by_phandle(id, parent, name, &dev);
388 	return uclass_get_device_tail(dev, ret, devp);
389 }
390 #endif
391 
392 int uclass_first_device(enum uclass_id id, struct udevice **devp)
393 {
394 	struct udevice *dev;
395 	int ret;
396 
397 	*devp = NULL;
398 	ret = uclass_find_first_device(id, &dev);
399 	if (!dev)
400 		return 0;
401 	return uclass_get_device_tail(dev, ret, devp);
402 }
403 
404 int uclass_next_device(struct udevice **devp)
405 {
406 	struct udevice *dev = *devp;
407 	int ret;
408 
409 	*devp = NULL;
410 	ret = uclass_find_next_device(&dev);
411 	if (!dev)
412 		return 0;
413 	return uclass_get_device_tail(dev, ret, devp);
414 }
415 
416 int uclass_bind_device(struct udevice *dev)
417 {
418 	struct uclass *uc;
419 	int ret;
420 
421 	uc = dev->uclass;
422 	list_add_tail(&dev->uclass_node, &uc->dev_head);
423 
424 	if (dev->parent) {
425 		struct uclass_driver *uc_drv = dev->parent->uclass->uc_drv;
426 
427 		if (uc_drv->child_post_bind) {
428 			ret = uc_drv->child_post_bind(dev);
429 			if (ret)
430 				goto err;
431 		}
432 	}
433 
434 	return 0;
435 err:
436 	/* There is no need to undo the parent's post_bind call */
437 	list_del(&dev->uclass_node);
438 
439 	return ret;
440 }
441 
442 #if CONFIG_IS_ENABLED(DM_DEVICE_REMOVE)
443 int uclass_unbind_device(struct udevice *dev)
444 {
445 	struct uclass *uc;
446 	int ret;
447 
448 	uc = dev->uclass;
449 	if (uc->uc_drv->pre_unbind) {
450 		ret = uc->uc_drv->pre_unbind(dev);
451 		if (ret)
452 			return ret;
453 	}
454 
455 	list_del(&dev->uclass_node);
456 	return 0;
457 }
458 #endif
459 
460 int uclass_resolve_seq(struct udevice *dev)
461 {
462 	struct udevice *dup;
463 	int seq;
464 	int ret;
465 
466 	assert(dev->seq == -1);
467 	ret = uclass_find_device_by_seq(dev->uclass->uc_drv->id, dev->req_seq,
468 					false, &dup);
469 	if (!ret) {
470 		dm_warn("Device '%s': seq %d is in use by '%s'\n",
471 			dev->name, dev->req_seq, dup->name);
472 	} else if (ret == -ENODEV) {
473 		/* Our requested sequence number is available */
474 		if (dev->req_seq != -1)
475 			return dev->req_seq;
476 	} else {
477 		return ret;
478 	}
479 
480 	for (seq = 0; seq < DM_MAX_SEQ; seq++) {
481 		ret = uclass_find_device_by_seq(dev->uclass->uc_drv->id, seq,
482 						false, &dup);
483 		if (ret == -ENODEV)
484 			break;
485 		if (ret)
486 			return ret;
487 	}
488 	return seq;
489 }
490 
491 int uclass_pre_probe_device(struct udevice *dev)
492 {
493 	struct uclass_driver *uc_drv;
494 	int ret;
495 
496 	uc_drv = dev->uclass->uc_drv;
497 	if (uc_drv->pre_probe) {
498 		ret = uc_drv->pre_probe(dev);
499 		if (ret)
500 			return ret;
501 	}
502 
503 	if (!dev->parent)
504 		return 0;
505 	uc_drv = dev->parent->uclass->uc_drv;
506 	if (uc_drv->child_pre_probe)
507 		return uc_drv->child_pre_probe(dev);
508 
509 	return 0;
510 }
511 
512 int uclass_post_probe_device(struct udevice *dev)
513 {
514 	struct uclass_driver *uc_drv = dev->uclass->uc_drv;
515 
516 	if (uc_drv->post_probe)
517 		return uc_drv->post_probe(dev);
518 
519 	return 0;
520 }
521 
522 #if CONFIG_IS_ENABLED(DM_DEVICE_REMOVE)
523 int uclass_pre_remove_device(struct udevice *dev)
524 {
525 	struct uclass *uc;
526 	int ret;
527 
528 	uc = dev->uclass;
529 	if (uc->uc_drv->pre_remove) {
530 		ret = uc->uc_drv->pre_remove(dev);
531 		if (ret)
532 			return ret;
533 	}
534 
535 	return 0;
536 }
537 #endif
538