xref: /openbmc/u-boot/drivers/core/device.c (revision 709ea543)
1 /*
2  * Device manager
3  *
4  * Copyright (c) 2013 Google, Inc
5  *
6  * (C) Copyright 2012
7  * Pavel Herrmann <morpheus.ibis@gmail.com>
8  *
9  * SPDX-License-Identifier:	GPL-2.0+
10  */
11 
12 #include <common.h>
13 #include <malloc.h>
14 #include <dm/device.h>
15 #include <dm/device-internal.h>
16 #include <dm/lists.h>
17 #include <dm/platdata.h>
18 #include <dm/uclass.h>
19 #include <dm/uclass-internal.h>
20 #include <dm/util.h>
21 #include <linux/err.h>
22 #include <linux/list.h>
23 
24 /**
25  * device_chld_unbind() - Unbind all device's children from the device
26  *
27  * On error, the function continues to unbind all children, and reports the
28  * first error.
29  *
30  * @dev:	The device that is to be stripped of its children
31  * @return 0 on success, -ve on error
32  */
33 static int device_chld_unbind(struct udevice *dev)
34 {
35 	struct udevice *pos, *n;
36 	int ret, saved_ret = 0;
37 
38 	assert(dev);
39 
40 	list_for_each_entry_safe(pos, n, &dev->child_head, sibling_node) {
41 		ret = device_unbind(pos);
42 		if (ret && !saved_ret)
43 			saved_ret = ret;
44 	}
45 
46 	return saved_ret;
47 }
48 
49 /**
50  * device_chld_remove() - Stop all device's children
51  * @dev:	The device whose children are to be removed
52  * @return 0 on success, -ve on error
53  */
54 static int device_chld_remove(struct udevice *dev)
55 {
56 	struct udevice *pos, *n;
57 	int ret;
58 
59 	assert(dev);
60 
61 	list_for_each_entry_safe(pos, n, &dev->child_head, sibling_node) {
62 		ret = device_remove(pos);
63 		if (ret)
64 			return ret;
65 	}
66 
67 	return 0;
68 }
69 
70 int device_bind(struct udevice *parent, struct driver *drv, const char *name,
71 		void *platdata, int of_offset, struct udevice **devp)
72 {
73 	struct udevice *dev;
74 	struct uclass *uc;
75 	int ret = 0;
76 
77 	*devp = NULL;
78 	if (!name)
79 		return -EINVAL;
80 
81 	ret = uclass_get(drv->id, &uc);
82 	if (ret)
83 		return ret;
84 
85 	dev = calloc(1, sizeof(struct udevice));
86 	if (!dev)
87 		return -ENOMEM;
88 
89 	INIT_LIST_HEAD(&dev->sibling_node);
90 	INIT_LIST_HEAD(&dev->child_head);
91 	INIT_LIST_HEAD(&dev->uclass_node);
92 	dev->platdata = platdata;
93 	dev->name = name;
94 	dev->of_offset = of_offset;
95 	dev->parent = parent;
96 	dev->driver = drv;
97 	dev->uclass = uc;
98 	if (!dev->platdata && drv->platdata_auto_alloc_size)
99 		dev->flags |= DM_FLAG_ALLOC_PDATA;
100 
101 	/* put dev into parent's successor list */
102 	if (parent)
103 		list_add_tail(&dev->sibling_node, &parent->child_head);
104 
105 	ret = uclass_bind_device(dev);
106 	if (ret)
107 		goto fail_bind;
108 
109 	/* if we fail to bind we remove device from successors and free it */
110 	if (drv->bind) {
111 		ret = drv->bind(dev);
112 		if (ret) {
113 			if (uclass_unbind_device(dev)) {
114 				dm_warn("Failed to unbind dev '%s' on error path\n",
115 					dev->name);
116 			}
117 			goto fail_bind;
118 		}
119 	}
120 	if (parent)
121 		dm_dbg("Bound device %s to %s\n", dev->name, parent->name);
122 	*devp = dev;
123 
124 	return 0;
125 
126 fail_bind:
127 	list_del(&dev->sibling_node);
128 	free(dev);
129 	return ret;
130 }
131 
132 int device_bind_by_name(struct udevice *parent, const struct driver_info *info,
133 			struct udevice **devp)
134 {
135 	struct driver *drv;
136 
137 	drv = lists_driver_lookup_name(info->name);
138 	if (!drv)
139 		return -ENOENT;
140 
141 	return device_bind(parent, drv, info->name, (void *)info->platdata,
142 			   -1, devp);
143 }
144 
145 int device_unbind(struct udevice *dev)
146 {
147 	struct driver *drv;
148 	int ret;
149 
150 	if (!dev)
151 		return -EINVAL;
152 
153 	if (dev->flags & DM_FLAG_ACTIVATED)
154 		return -EINVAL;
155 
156 	drv = dev->driver;
157 	assert(drv);
158 
159 	if (drv->unbind) {
160 		ret = drv->unbind(dev);
161 		if (ret)
162 			return ret;
163 	}
164 
165 	ret = device_chld_unbind(dev);
166 	if (ret)
167 		return ret;
168 
169 	ret = uclass_unbind_device(dev);
170 	if (ret)
171 		return ret;
172 
173 	if (dev->parent)
174 		list_del(&dev->sibling_node);
175 	free(dev);
176 
177 	return 0;
178 }
179 
180 /**
181  * device_free() - Free memory buffers allocated by a device
182  * @dev:	Device that is to be started
183  */
184 static void device_free(struct udevice *dev)
185 {
186 	int size;
187 
188 	if (dev->driver->priv_auto_alloc_size) {
189 		free(dev->priv);
190 		dev->priv = NULL;
191 	}
192 	if (dev->flags & DM_FLAG_ALLOC_PDATA) {
193 		free(dev->platdata);
194 		dev->platdata = NULL;
195 	}
196 	size = dev->uclass->uc_drv->per_device_auto_alloc_size;
197 	if (size) {
198 		free(dev->uclass_priv);
199 		dev->uclass_priv = NULL;
200 	}
201 }
202 
203 int device_probe(struct udevice *dev)
204 {
205 	struct driver *drv;
206 	int size = 0;
207 	int ret;
208 
209 	if (!dev)
210 		return -EINVAL;
211 
212 	if (dev->flags & DM_FLAG_ACTIVATED)
213 		return 0;
214 
215 	drv = dev->driver;
216 	assert(drv);
217 
218 	/* Allocate private data and platdata if requested */
219 	if (drv->priv_auto_alloc_size) {
220 		dev->priv = calloc(1, drv->priv_auto_alloc_size);
221 		if (!dev->priv) {
222 			ret = -ENOMEM;
223 			goto fail;
224 		}
225 	}
226 	/* Allocate private data if requested */
227 	if (dev->flags & DM_FLAG_ALLOC_PDATA) {
228 		dev->platdata = calloc(1, drv->platdata_auto_alloc_size);
229 		if (!dev->platdata) {
230 			ret = -ENOMEM;
231 			goto fail;
232 		}
233 	}
234 	size = dev->uclass->uc_drv->per_device_auto_alloc_size;
235 	if (size) {
236 		dev->uclass_priv = calloc(1, size);
237 		if (!dev->uclass_priv) {
238 			ret = -ENOMEM;
239 			goto fail;
240 		}
241 	}
242 
243 	/* Ensure all parents are probed */
244 	if (dev->parent) {
245 		ret = device_probe(dev->parent);
246 		if (ret)
247 			goto fail;
248 	}
249 
250 	if (drv->ofdata_to_platdata && dev->of_offset >= 0) {
251 		ret = drv->ofdata_to_platdata(dev);
252 		if (ret)
253 			goto fail;
254 	}
255 
256 	if (drv->probe) {
257 		ret = drv->probe(dev);
258 		if (ret)
259 			goto fail;
260 	}
261 
262 	dev->flags |= DM_FLAG_ACTIVATED;
263 
264 	ret = uclass_post_probe_device(dev);
265 	if (ret) {
266 		dev->flags &= ~DM_FLAG_ACTIVATED;
267 		goto fail_uclass;
268 	}
269 
270 	return 0;
271 fail_uclass:
272 	if (device_remove(dev)) {
273 		dm_warn("%s: Device '%s' failed to remove on error path\n",
274 			__func__, dev->name);
275 	}
276 fail:
277 	device_free(dev);
278 
279 	return ret;
280 }
281 
282 int device_remove(struct udevice *dev)
283 {
284 	struct driver *drv;
285 	int ret;
286 
287 	if (!dev)
288 		return -EINVAL;
289 
290 	if (!(dev->flags & DM_FLAG_ACTIVATED))
291 		return 0;
292 
293 	drv = dev->driver;
294 	assert(drv);
295 
296 	ret = uclass_pre_remove_device(dev);
297 	if (ret)
298 		return ret;
299 
300 	ret = device_chld_remove(dev);
301 	if (ret)
302 		goto err;
303 
304 	if (drv->remove) {
305 		ret = drv->remove(dev);
306 		if (ret)
307 			goto err_remove;
308 	}
309 
310 	device_free(dev);
311 
312 	dev->flags &= ~DM_FLAG_ACTIVATED;
313 
314 	return 0;
315 
316 err_remove:
317 	/* We can't put the children back */
318 	dm_warn("%s: Device '%s' failed to remove, but children are gone\n",
319 		__func__, dev->name);
320 err:
321 	ret = uclass_post_probe_device(dev);
322 	if (ret) {
323 		dm_warn("%s: Device '%s' failed to post_probe on error path\n",
324 			__func__, dev->name);
325 	}
326 
327 	return ret;
328 }
329 
330 void *dev_get_platdata(struct udevice *dev)
331 {
332 	if (!dev) {
333 		dm_warn("%s: null device", __func__);
334 		return NULL;
335 	}
336 
337 	return dev->platdata;
338 }
339 
340 void *dev_get_priv(struct udevice *dev)
341 {
342 	if (!dev) {
343 		dm_warn("%s: null device", __func__);
344 		return NULL;
345 	}
346 
347 	return dev->priv;
348 }
349