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 <common.h>
14 #include <errno.h>
15 #include <log.h>
16 #include <malloc.h>
17 #include <dm/device.h>
18 #include <dm/device-internal.h>
19 #include <dm/uclass.h>
20 #include <dm/uclass-internal.h>
21 #include <dm/util.h>
22 #include <power-domain.h>
23 #include <asm/global_data.h>
24 
device_chld_unbind(struct udevice * dev,struct driver * drv)25 int device_chld_unbind(struct udevice *dev, struct driver *drv)
26 {
27 	struct udevice *pos, *n;
28 	int ret, saved_ret = 0;
29 
30 	assert(dev);
31 
32 	list_for_each_entry_safe(pos, n, &dev->child_head, sibling_node) {
33 		if (drv && (pos->driver != drv))
34 			continue;
35 
36 		ret = device_unbind(pos);
37 		if (ret && !saved_ret) {
38 			log_warning("device '%s' failed to unbind\n",
39 				    pos->name);
40 			saved_ret = ret;
41 		}
42 	}
43 
44 	return log_ret(saved_ret);
45 }
46 
device_chld_remove(struct udevice * dev,struct driver * drv,uint flags)47 int device_chld_remove(struct udevice *dev, struct driver *drv,
48 		       uint flags)
49 {
50 	struct udevice *pos, *n;
51 	int result = 0;
52 
53 	assert(dev);
54 
55 	list_for_each_entry_safe(pos, n, &dev->child_head, sibling_node) {
56 		int ret;
57 
58 		if (drv && (pos->driver != drv))
59 			continue;
60 
61 		ret = device_remove(pos, flags);
62 		if (ret == -EPROBE_DEFER)
63 			result = ret;
64 		else if (ret && ret != -EKEYREJECTED)
65 			return ret;
66 	}
67 
68 	return result;
69 }
70 
device_unbind(struct udevice * dev)71 int device_unbind(struct udevice *dev)
72 {
73 	const struct driver *drv;
74 	int ret;
75 
76 	if (!dev)
77 		return log_msg_ret("dev", -EINVAL);
78 
79 	if (dev_get_flags(dev) & DM_FLAG_ACTIVATED)
80 		return log_msg_ret("active", -EINVAL);
81 
82 	if (!(dev_get_flags(dev) & DM_FLAG_BOUND))
83 		return log_msg_ret("not-bound", -EINVAL);
84 
85 	drv = dev->driver;
86 	assert(drv);
87 
88 	if (drv->unbind) {
89 		ret = drv->unbind(dev);
90 		if (ret)
91 			return log_msg_ret("unbind", ret);
92 	}
93 
94 	ret = device_chld_unbind(dev, NULL);
95 	if (ret)
96 		return log_msg_ret("child unbind", ret);
97 
98 	if (dev_get_flags(dev) & DM_FLAG_ALLOC_PDATA) {
99 		free(dev_get_plat(dev));
100 		dev_set_plat(dev, NULL);
101 	}
102 	if (dev_get_flags(dev) & DM_FLAG_ALLOC_UCLASS_PDATA) {
103 		free(dev_get_uclass_plat(dev));
104 		dev_set_uclass_plat(dev, NULL);
105 	}
106 	if (dev_get_flags(dev) & DM_FLAG_ALLOC_PARENT_PDATA) {
107 		free(dev_get_parent_plat(dev));
108 		dev_set_parent_plat(dev, NULL);
109 	}
110 	ret = uclass_unbind_device(dev);
111 	if (ret)
112 		return log_msg_ret("uc", ret);
113 
114 	if (dev->parent)
115 		list_del(&dev->sibling_node);
116 
117 	devres_release_all(dev);
118 
119 	if (dev_get_flags(dev) & DM_FLAG_NAME_ALLOCED)
120 		free((char *)dev->name);
121 	free(dev);
122 
123 	return 0;
124 }
125 
126 /**
127  * device_free() - Free memory buffers allocated by a device
128  * @dev:	Device that is to be started
129  */
device_free(struct udevice * dev)130 void device_free(struct udevice *dev)
131 {
132 	int size;
133 
134 	if (dev->driver->priv_auto) {
135 		free(dev_get_priv(dev));
136 		dev_set_priv(dev, NULL);
137 	}
138 	size = dev->uclass->uc_drv->per_device_auto;
139 	if (size) {
140 		free(dev_get_uclass_priv(dev));
141 		dev_set_uclass_priv(dev, NULL);
142 	}
143 	if (dev->parent) {
144 		size = dev->parent->driver->per_child_auto;
145 		if (!size) {
146 			size = dev->parent->uclass->uc_drv->
147 					per_child_auto;
148 		}
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 	/*
210 	 * If the child returns EKEYREJECTED, continue. It just means that it
211 	 * didn't match the flags.
212 	 */
213 	ret = device_chld_remove(dev, NULL, flags);
214 	if (ret && ret != -EKEYREJECTED)
215 		return ret;
216 
217 	/*
218 	 * Remove the device if called with the "normal" remove flag set,
219 	 * or if the remove flag matches any of the drivers remove flags
220 	 */
221 	drv = dev->driver;
222 	assert(drv);
223 	ret = flags_remove(flags, drv->flags);
224 	if (ret) {
225 		log_debug("%s: When removing: flags=%x, drv->flags=%x, err=%d\n",
226 			  dev->name, flags, drv->flags, ret);
227 		return ret;
228 	}
229 
230 	ret = uclass_pre_remove_device(dev);
231 	if (ret)
232 		return ret;
233 
234 	if (drv->remove) {
235 		ret = drv->remove(dev);
236 		if (ret)
237 			goto err_remove;
238 	}
239 
240 	if (dev->parent && dev->parent->driver->child_post_remove) {
241 		ret = dev->parent->driver->child_post_remove(dev);
242 		if (ret) {
243 			dm_warn("%s: Device '%s' failed child_post_remove()",
244 				__func__, dev->name);
245 		}
246 	}
247 
248 	if (!(flags & DM_REMOVE_NO_PD) &&
249 	    !(drv->flags &
250 	      (DM_FLAG_DEFAULT_PD_CTRL_OFF | DM_FLAG_LEAVE_PD_ON)) &&
251 	    dev != gd->cur_serial_dev)
252 		dev_power_domain_off(dev);
253 
254 	device_free(dev);
255 
256 	dev_bic_flags(dev, DM_FLAG_ACTIVATED);
257 
258 	return 0;
259 
260 err_remove:
261 	/* We can't put the children back */
262 	dm_warn("%s: Device '%s' failed to remove, but children are gone\n",
263 		__func__, dev->name);
264 
265 	return ret;
266 }
267