1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Device manager
4  *
5  * Copyright (c) 2014 Google, Inc
6  *
7  * (C) Copyright 2012
8  * Pavel Herrmann <morpheus.ibis@gmail.com>
9  */
10 
11 #define LOG_CATEGORY	LOGC_DM
12 
13 #include <errno.h>
14 #include <log.h>
15 #include <malloc.h>
16 #include <dm/device.h>
17 #include <dm/device-internal.h>
18 #include <dm/uclass.h>
19 #include <dm/uclass-internal.h>
20 #include <dm/util.h>
21 #include <power-domain.h>
22 #include <asm/global_data.h>
23 
device_chld_unbind(struct udevice * dev,struct driver * drv)24 int device_chld_unbind(struct udevice *dev, struct driver *drv)
25 {
26 	struct udevice *pos, *n;
27 	int ret, saved_ret = 0;
28 
29 	assert(dev);
30 
31 	device_foreach_child_safe(pos, n, dev) {
32 		if (drv && (pos->driver != drv))
33 			continue;
34 
35 		ret = device_unbind(pos);
36 		if (ret && !saved_ret) {
37 			log_warning("device '%s' failed to unbind\n",
38 				    pos->name);
39 			saved_ret = ret;
40 		}
41 	}
42 
43 	return log_ret(saved_ret);
44 }
45 
device_chld_remove(struct udevice * dev,struct driver * drv,uint flags)46 int device_chld_remove(struct udevice *dev, struct driver *drv,
47 		       uint flags)
48 {
49 	struct udevice *pos, *n;
50 	int result = 0;
51 
52 	assert(dev);
53 
54 	device_foreach_child_safe(pos, n, dev) {
55 		int ret;
56 
57 		if (drv && (pos->driver != drv))
58 			continue;
59 
60 		ret = device_remove(pos, flags);
61 		if (ret == -EPROBE_DEFER)
62 			result = ret;
63 		else if (ret && ret != -EKEYREJECTED)
64 			return ret;
65 	}
66 
67 	return result;
68 }
69 
device_unbind(struct udevice * dev)70 int device_unbind(struct udevice *dev)
71 {
72 	const struct driver *drv;
73 	int ret;
74 
75 	if (!dev)
76 		return log_msg_ret("dev", -EINVAL);
77 
78 	if (dev_get_flags(dev) & DM_FLAG_ACTIVATED)
79 		return log_msg_ret("active", -EINVAL);
80 
81 	if (!(dev_get_flags(dev) & DM_FLAG_BOUND))
82 		return log_msg_ret("not-bound", -EINVAL);
83 
84 	drv = dev->driver;
85 	assert(drv);
86 
87 	if (drv->unbind) {
88 		ret = drv->unbind(dev);
89 		if (ret)
90 			return log_msg_ret("unbind", ret);
91 	}
92 
93 	ret = device_chld_unbind(dev, NULL);
94 	if (ret)
95 		return log_msg_ret("child unbind", ret);
96 
97 	ret = uclass_pre_unbind_device(dev);
98 	if (ret)
99 		return log_msg_ret("uc", ret);
100 	if (dev_get_flags(dev) & DM_FLAG_ALLOC_PDATA) {
101 		free(dev_get_plat(dev));
102 		dev_set_plat(dev, NULL);
103 	}
104 	if (dev_get_flags(dev) & DM_FLAG_ALLOC_UCLASS_PDATA) {
105 		free(dev_get_uclass_plat(dev));
106 		dev_set_uclass_plat(dev, NULL);
107 	}
108 	if (dev_get_flags(dev) & DM_FLAG_ALLOC_PARENT_PDATA) {
109 		free(dev_get_parent_plat(dev));
110 		dev_set_parent_plat(dev, NULL);
111 	}
112 	ret = uclass_unbind_device(dev);
113 	if (ret)
114 		return log_msg_ret("uc", ret);
115 
116 	if (dev->parent)
117 		list_del(&dev->sibling_node);
118 
119 	devres_release_all(dev);
120 
121 	if (dev_get_flags(dev) & DM_FLAG_NAME_ALLOCED)
122 		free((char *)dev->name);
123 	free(dev);
124 
125 	return 0;
126 }
127 
128 /**
129  * device_free() - Free memory buffers allocated by a device
130  * @dev:	Device that is to be started
131  */
device_free(struct udevice * dev)132 void device_free(struct udevice *dev)
133 {
134 	int size;
135 
136 	if (dev->driver->priv_auto) {
137 		free(dev_get_priv(dev));
138 		dev_set_priv(dev, NULL);
139 	}
140 	size = dev->uclass->uc_drv->per_device_auto;
141 	if (size) {
142 		free(dev_get_uclass_priv(dev));
143 		dev_set_uclass_priv(dev, NULL);
144 	}
145 	if (dev->parent) {
146 		size = dev->parent->driver->per_child_auto;
147 		if (!size)
148 			size = dev->parent->uclass->uc_drv->per_child_auto;
149 		if (size) {
150 			free(dev_get_parent_priv(dev));
151 			dev_set_parent_priv(dev, NULL);
152 		}
153 	}
154 	dev_bic_flags(dev, DM_FLAG_PLATDATA_VALID);
155 
156 	devres_release_probe(dev);
157 }
158 
159 /**
160  * flags_remove() - Figure out whether to remove a device
161  *
162  * If this is called with @flags == DM_REMOVE_NON_VITAL | DM_REMOVE_ACTIVE_DMA,
163  * then it returns 0 (=go head and remove) if the device is not matked vital
164  * but is marked DM_REMOVE_ACTIVE_DMA.
165  *
166  * If this is called with @flags == DM_REMOVE_ACTIVE_DMA,
167  * then it returns 0 (=go head and remove) if the device is marked
168  * DM_REMOVE_ACTIVE_DMA, regardless of whether it is marked vital.
169  *
170  * @flags: Flags passed to device_remove()
171  * @drv_flags: Driver flags
172  * Return: 0 if the device should be removed,
173  * -EKEYREJECTED if @flags includes a flag in DM_REMOVE_ACTIVE_ALL but
174  *	@drv_flags does not (indicates that this device has nothing to do for
175  *	DMA shutdown or OS prepare)
176  * -EPROBE_DEFER if @flags is DM_REMOVE_NON_VITAL but @drv_flags contains
177  *	DM_FLAG_VITAL (indicates the device is vital and should not be removed)
178  */
flags_remove(uint flags,uint drv_flags)179 static int flags_remove(uint flags, uint drv_flags)
180 {
181 	if (!(flags & DM_REMOVE_NORMAL)) {
182 		bool vital_match;
183 		bool active_match;
184 
185 		active_match = !(flags & DM_REMOVE_ACTIVE_ALL) ||
186 			(drv_flags & flags);
187 		vital_match = !(flags & DM_REMOVE_NON_VITAL) ||
188 			!(drv_flags & DM_FLAG_VITAL);
189 		if (!vital_match)
190 			return -EPROBE_DEFER;
191 		if (!active_match)
192 			return -EKEYREJECTED;
193 	}
194 
195 	return 0;
196 }
197 
device_remove(struct udevice * dev,uint flags)198 int device_remove(struct udevice *dev, uint flags)
199 {
200 	const struct driver *drv;
201 	int ret;
202 
203 	if (!dev)
204 		return -EINVAL;
205 
206 	if (!(dev_get_flags(dev) & DM_FLAG_ACTIVATED))
207 		return 0;
208 
209 	ret = device_notify(dev, EVT_DM_PRE_REMOVE);
210 	if (ret)
211 		return ret;
212 
213 	/*
214 	 * If the child returns EKEYREJECTED, continue. It just means that it
215 	 * didn't match the flags.
216 	 */
217 	ret = device_chld_remove(dev, NULL, flags);
218 	if (ret && ret != -EKEYREJECTED)
219 		return ret;
220 
221 	/*
222 	 * Remove the device if called with the "normal" remove flag set,
223 	 * or if the remove flag matches any of the drivers remove flags
224 	 */
225 	drv = dev->driver;
226 	assert(drv);
227 	ret = flags_remove(flags, drv->flags);
228 	if (ret) {
229 		log_debug("%s: When removing: flags=%x, drv->flags=%x, err=%d\n",
230 			  dev->name, flags, drv->flags, ret);
231 		return ret;
232 	}
233 
234 	ret = uclass_pre_remove_device(dev);
235 	if (ret)
236 		return ret;
237 
238 	if (drv->remove) {
239 		ret = drv->remove(dev);
240 		if (ret)
241 			goto err_remove;
242 	}
243 
244 	if (dev->parent && dev->parent->driver->child_post_remove) {
245 		ret = dev->parent->driver->child_post_remove(dev);
246 		if (ret) {
247 			dm_warn("%s: Device '%s' failed child_post_remove()",
248 				__func__, dev->name);
249 		}
250 	}
251 
252 	if (!(flags & DM_REMOVE_NO_PD) &&
253 	    !(drv->flags &
254 	      (DM_FLAG_DEFAULT_PD_CTRL_OFF | DM_FLAG_LEAVE_PD_ON)) &&
255 	    dev != gd->cur_serial_dev)
256 		dev_power_domain_off(dev);
257 
258 	device_free(dev);
259 
260 	dev_bic_flags(dev, DM_FLAG_ACTIVATED);
261 
262 	ret = device_notify(dev, EVT_DM_POST_REMOVE);
263 	if (ret)
264 		goto err_remove;
265 
266 	return 0;
267 
268 err_remove:
269 	/* We can't put the children back */
270 	dm_warn("%s: Device '%s' failed to remove, but children are gone\n",
271 		__func__, dev->name);
272 
273 	return ret;
274 }
275