xref: /openbmc/u-boot/drivers/core/uclass.c (revision b2e02d28)
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 		dm_warn("Cannot find uclass for id %d: please add the UCLASS_DRIVER() declaration for this UCLASS_... id\n",
60 			id);
61 		return -ENOENT;
62 	}
63 	uc = calloc(1, sizeof(*uc));
64 	if (!uc)
65 		return -ENOMEM;
66 	if (uc_drv->priv_auto_alloc_size) {
67 		uc->priv = calloc(1, uc_drv->priv_auto_alloc_size);
68 		if (!uc->priv) {
69 			ret = -ENOMEM;
70 			goto fail_mem;
71 		}
72 	}
73 	uc->uc_drv = uc_drv;
74 	INIT_LIST_HEAD(&uc->sibling_node);
75 	INIT_LIST_HEAD(&uc->dev_head);
76 	list_add(&uc->sibling_node, &DM_UCLASS_ROOT_NON_CONST);
77 
78 	if (uc_drv->init) {
79 		ret = uc_drv->init(uc);
80 		if (ret)
81 			goto fail;
82 	}
83 
84 	*ucp = uc;
85 
86 	return 0;
87 fail:
88 	if (uc_drv->priv_auto_alloc_size) {
89 		free(uc->priv);
90 		uc->priv = NULL;
91 	}
92 	list_del(&uc->sibling_node);
93 fail_mem:
94 	free(uc);
95 
96 	return ret;
97 }
98 
99 int uclass_destroy(struct uclass *uc)
100 {
101 	struct uclass_driver *uc_drv;
102 	struct udevice *dev, *tmp;
103 	int ret;
104 
105 	list_for_each_entry_safe(dev, tmp, &uc->dev_head, uclass_node) {
106 		ret = device_remove(dev);
107 		if (ret)
108 			return ret;
109 		ret = device_unbind(dev);
110 		if (ret)
111 			return ret;
112 	}
113 
114 	uc_drv = uc->uc_drv;
115 	if (uc_drv->destroy)
116 		uc_drv->destroy(uc);
117 	list_del(&uc->sibling_node);
118 	if (uc_drv->priv_auto_alloc_size)
119 		free(uc->priv);
120 	free(uc);
121 
122 	return 0;
123 }
124 
125 int uclass_get(enum uclass_id id, struct uclass **ucp)
126 {
127 	struct uclass *uc;
128 
129 	*ucp = NULL;
130 	uc = uclass_find(id);
131 	if (!uc)
132 		return uclass_add(id, ucp);
133 	*ucp = uc;
134 
135 	return 0;
136 }
137 
138 int uclass_find_device(enum uclass_id id, int index, struct udevice **devp)
139 {
140 	struct uclass *uc;
141 	struct udevice *dev;
142 	int ret;
143 
144 	*devp = NULL;
145 	ret = uclass_get(id, &uc);
146 	if (ret)
147 		return ret;
148 
149 	list_for_each_entry(dev, &uc->dev_head, uclass_node) {
150 		if (!index--) {
151 			*devp = dev;
152 			return 0;
153 		}
154 	}
155 
156 	return -ENODEV;
157 }
158 
159 int uclass_find_device_by_seq(enum uclass_id id, int seq_or_req_seq,
160 			      bool find_req_seq, struct udevice **devp)
161 {
162 	struct uclass *uc;
163 	struct udevice *dev;
164 	int ret;
165 
166 	*devp = NULL;
167 	debug("%s: %d %d\n", __func__, find_req_seq, seq_or_req_seq);
168 	if (seq_or_req_seq == -1)
169 		return -ENODEV;
170 	ret = uclass_get(id, &uc);
171 	if (ret)
172 		return ret;
173 
174 	list_for_each_entry(dev, &uc->dev_head, uclass_node) {
175 		debug("   - %d %d\n", dev->req_seq, dev->seq);
176 		if ((find_req_seq ? dev->req_seq : dev->seq) ==
177 				seq_or_req_seq) {
178 			*devp = dev;
179 			debug("   - found\n");
180 			return 0;
181 		}
182 	}
183 	debug("   - not found\n");
184 
185 	return -ENODEV;
186 }
187 
188 static int uclass_find_device_by_of_offset(enum uclass_id id, int node,
189 					   struct udevice **devp)
190 {
191 	struct uclass *uc;
192 	struct udevice *dev;
193 	int ret;
194 
195 	*devp = NULL;
196 	if (node < 0)
197 		return -ENODEV;
198 	ret = uclass_get(id, &uc);
199 	if (ret)
200 		return ret;
201 
202 	list_for_each_entry(dev, &uc->dev_head, uclass_node) {
203 		if (dev->of_offset == node) {
204 			*devp = dev;
205 			return 0;
206 		}
207 	}
208 
209 	return -ENODEV;
210 }
211 
212 /**
213  * uclass_get_device_tail() - handle the end of a get_device call
214  *
215  * This handles returning an error or probing a device as needed.
216  *
217  * @dev: Device that needs to be probed
218  * @ret: Error to return. If non-zero then the device is not probed
219  * @devp: Returns the value of 'dev' if there is no error
220  * @return ret, if non-zero, else the result of the device_probe() call
221  */
222 static int uclass_get_device_tail(struct udevice *dev, int ret,
223 				  struct udevice **devp)
224 {
225 	if (ret)
226 		return ret;
227 
228 	ret = device_probe(dev);
229 	if (ret)
230 		return ret;
231 
232 	*devp = dev;
233 
234 	return 0;
235 }
236 
237 int uclass_get_device(enum uclass_id id, int index, struct udevice **devp)
238 {
239 	struct udevice *dev;
240 	int ret;
241 
242 	*devp = NULL;
243 	ret = uclass_find_device(id, index, &dev);
244 	return uclass_get_device_tail(dev, ret, devp);
245 }
246 
247 int uclass_get_device_by_seq(enum uclass_id id, int seq, struct udevice **devp)
248 {
249 	struct udevice *dev;
250 	int ret;
251 
252 	*devp = NULL;
253 	ret = uclass_find_device_by_seq(id, seq, false, &dev);
254 	if (ret == -ENODEV) {
255 		/*
256 		 * We didn't find it in probed devices. See if there is one
257 		 * that will request this seq if probed.
258 		 */
259 		ret = uclass_find_device_by_seq(id, seq, true, &dev);
260 	}
261 	return uclass_get_device_tail(dev, ret, devp);
262 }
263 
264 int uclass_get_device_by_of_offset(enum uclass_id id, int node,
265 				   struct udevice **devp)
266 {
267 	struct udevice *dev;
268 	int ret;
269 
270 	*devp = NULL;
271 	ret = uclass_find_device_by_of_offset(id, node, &dev);
272 	return uclass_get_device_tail(dev, ret, devp);
273 }
274 
275 int uclass_first_device(enum uclass_id id, struct udevice **devp)
276 {
277 	struct uclass *uc;
278 	struct udevice *dev;
279 	int ret;
280 
281 	*devp = NULL;
282 	ret = uclass_get(id, &uc);
283 	if (ret)
284 		return ret;
285 	if (list_empty(&uc->dev_head))
286 		return 0;
287 
288 	dev = list_first_entry(&uc->dev_head, struct udevice, uclass_node);
289 	ret = device_probe(dev);
290 	if (ret)
291 		return ret;
292 	*devp = dev;
293 
294 	return 0;
295 }
296 
297 int uclass_next_device(struct udevice **devp)
298 {
299 	struct udevice *dev = *devp;
300 	int ret;
301 
302 	*devp = NULL;
303 	if (list_is_last(&dev->uclass_node, &dev->uclass->dev_head))
304 		return 0;
305 
306 	dev = list_entry(dev->uclass_node.next, struct udevice,
307 			 uclass_node);
308 	ret = device_probe(dev);
309 	if (ret)
310 		return ret;
311 	*devp = dev;
312 
313 	return 0;
314 }
315 
316 int uclass_bind_device(struct udevice *dev)
317 {
318 	struct uclass *uc;
319 	int ret;
320 
321 	uc = dev->uclass;
322 
323 	list_add_tail(&dev->uclass_node, &uc->dev_head);
324 
325 	if (uc->uc_drv->post_bind) {
326 		ret = uc->uc_drv->post_bind(dev);
327 		if (ret) {
328 			list_del(&dev->uclass_node);
329 			return ret;
330 		}
331 	}
332 
333 	return 0;
334 }
335 
336 int uclass_unbind_device(struct udevice *dev)
337 {
338 	struct uclass *uc;
339 	int ret;
340 
341 	uc = dev->uclass;
342 	if (uc->uc_drv->pre_unbind) {
343 		ret = uc->uc_drv->pre_unbind(dev);
344 		if (ret)
345 			return ret;
346 	}
347 
348 	list_del(&dev->uclass_node);
349 	return 0;
350 }
351 
352 int uclass_resolve_seq(struct udevice *dev)
353 {
354 	struct udevice *dup;
355 	int seq;
356 	int ret;
357 
358 	assert(dev->seq == -1);
359 	ret = uclass_find_device_by_seq(dev->uclass->uc_drv->id, dev->req_seq,
360 					false, &dup);
361 	if (!ret) {
362 		dm_warn("Device '%s': seq %d is in use by '%s'\n",
363 			dev->name, dev->req_seq, dup->name);
364 	} else if (ret == -ENODEV) {
365 		/* Our requested sequence number is available */
366 		if (dev->req_seq != -1)
367 			return dev->req_seq;
368 	} else {
369 		return ret;
370 	}
371 
372 	for (seq = 0; seq < DM_MAX_SEQ; seq++) {
373 		ret = uclass_find_device_by_seq(dev->uclass->uc_drv->id, seq,
374 						false, &dup);
375 		if (ret == -ENODEV)
376 			break;
377 		if (ret)
378 			return ret;
379 	}
380 	return seq;
381 }
382 
383 int uclass_post_probe_device(struct udevice *dev)
384 {
385 	struct uclass_driver *uc_drv = dev->uclass->uc_drv;
386 
387 	if (uc_drv->post_probe)
388 		return uc_drv->post_probe(dev);
389 
390 	return 0;
391 }
392 
393 int uclass_pre_remove_device(struct udevice *dev)
394 {
395 	struct uclass_driver *uc_drv;
396 	struct uclass *uc;
397 	int ret;
398 
399 	uc = dev->uclass;
400 	uc_drv = uc->uc_drv;
401 	if (uc->uc_drv->pre_remove) {
402 		ret = uc->uc_drv->pre_remove(dev);
403 		if (ret)
404 			return ret;
405 	}
406 	if (uc_drv->per_device_auto_alloc_size) {
407 		free(dev->uclass_priv);
408 		dev->uclass_priv = NULL;
409 	}
410 	dev->seq = -1;
411 
412 	return 0;
413 }
414