xref: /openbmc/u-boot/drivers/core/device-remove.c (revision d891ab95)
1 /*
2  * Device manager
3  *
4  * Copyright (c) 2014 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 <errno.h>
14 #include <malloc.h>
15 #include <dm/device.h>
16 #include <dm/device-internal.h>
17 #include <dm/uclass.h>
18 #include <dm/uclass-internal.h>
19 #include <dm/util.h>
20 
21 /**
22  * device_chld_unbind() - Unbind all device's children from the device
23  *
24  * On error, the function continues to unbind all children, and reports the
25  * first error.
26  *
27  * @dev:	The device that is to be stripped of its children
28  * @return 0 on success, -ve on error
29  */
30 static int device_chld_unbind(struct udevice *dev)
31 {
32 	struct udevice *pos, *n;
33 	int ret, saved_ret = 0;
34 
35 	assert(dev);
36 
37 	list_for_each_entry_safe(pos, n, &dev->child_head, sibling_node) {
38 		ret = device_unbind(pos);
39 		if (ret && !saved_ret)
40 			saved_ret = ret;
41 	}
42 
43 	return saved_ret;
44 }
45 
46 /**
47  * device_chld_remove() - Stop all device's children
48  * @dev:	The device whose children are to be removed
49  * @pre_os_remove: Flag, if this functions is called in the pre-OS stage
50  * @return 0 on success, -ve on error
51  */
52 static int device_chld_remove(struct udevice *dev, uint flags)
53 {
54 	struct udevice *pos, *n;
55 	int ret;
56 
57 	assert(dev);
58 
59 	list_for_each_entry_safe(pos, n, &dev->child_head, sibling_node) {
60 		ret = device_remove(pos, flags);
61 		if (ret)
62 			return ret;
63 	}
64 
65 	return 0;
66 }
67 
68 int device_unbind(struct udevice *dev)
69 {
70 	const struct driver *drv;
71 	int ret;
72 
73 	if (!dev)
74 		return -EINVAL;
75 
76 	if (dev->flags & DM_FLAG_ACTIVATED)
77 		return -EINVAL;
78 
79 	if (!(dev->flags & DM_FLAG_BOUND))
80 		return -EINVAL;
81 
82 	drv = dev->driver;
83 	assert(drv);
84 
85 	if (drv->unbind) {
86 		ret = drv->unbind(dev);
87 		if (ret)
88 			return ret;
89 	}
90 
91 	ret = device_chld_unbind(dev);
92 	if (ret)
93 		return ret;
94 
95 	if (dev->flags & DM_FLAG_ALLOC_PDATA) {
96 		free(dev->platdata);
97 		dev->platdata = NULL;
98 	}
99 	if (dev->flags & DM_FLAG_ALLOC_UCLASS_PDATA) {
100 		free(dev->uclass_platdata);
101 		dev->uclass_platdata = NULL;
102 	}
103 	if (dev->flags & DM_FLAG_ALLOC_PARENT_PDATA) {
104 		free(dev->parent_platdata);
105 		dev->parent_platdata = NULL;
106 	}
107 	ret = uclass_unbind_device(dev);
108 	if (ret)
109 		return ret;
110 
111 	if (dev->parent)
112 		list_del(&dev->sibling_node);
113 
114 	devres_release_all(dev);
115 
116 	if (dev->flags & DM_FLAG_NAME_ALLOCED)
117 		free((char *)dev->name);
118 	free(dev);
119 
120 	return 0;
121 }
122 
123 /**
124  * device_free() - Free memory buffers allocated by a device
125  * @dev:	Device that is to be started
126  */
127 void device_free(struct udevice *dev)
128 {
129 	int size;
130 
131 	if (dev->driver->priv_auto_alloc_size) {
132 		free(dev->priv);
133 		dev->priv = NULL;
134 	}
135 	size = dev->uclass->uc_drv->per_device_auto_alloc_size;
136 	if (size) {
137 		free(dev->uclass_priv);
138 		dev->uclass_priv = NULL;
139 	}
140 	if (dev->parent) {
141 		size = dev->parent->driver->per_child_auto_alloc_size;
142 		if (!size) {
143 			size = dev->parent->uclass->uc_drv->
144 					per_child_auto_alloc_size;
145 		}
146 		if (size) {
147 			free(dev->parent_priv);
148 			dev->parent_priv = NULL;
149 		}
150 	}
151 
152 	devres_release_probe(dev);
153 }
154 
155 int device_remove(struct udevice *dev, uint flags)
156 {
157 	const struct driver *drv;
158 	int ret;
159 
160 	if (!dev)
161 		return -EINVAL;
162 
163 	if (!(dev->flags & DM_FLAG_ACTIVATED))
164 		return 0;
165 
166 	drv = dev->driver;
167 	assert(drv);
168 
169 	ret = uclass_pre_remove_device(dev);
170 	if (ret)
171 		return ret;
172 
173 	ret = device_chld_remove(dev, flags);
174 	if (ret)
175 		goto err;
176 
177 	/*
178 	 * Remove the device if called with the "normal" remove flag set,
179 	 * or if the remove flag matches any of the drivers remove flags
180 	 */
181 	if (drv->remove &&
182 	    ((flags & DM_REMOVE_NORMAL) ||
183 	     (flags & (drv->flags & DM_FLAG_ACTIVE_DMA)))) {
184 		ret = drv->remove(dev);
185 		if (ret)
186 			goto err_remove;
187 	}
188 
189 	if (dev->parent && dev->parent->driver->child_post_remove) {
190 		ret = dev->parent->driver->child_post_remove(dev);
191 		if (ret) {
192 			dm_warn("%s: Device '%s' failed child_post_remove()",
193 				__func__, dev->name);
194 		}
195 	}
196 
197 	if ((flags & DM_REMOVE_NORMAL) ||
198 	    (flags & (drv->flags & DM_FLAG_ACTIVE_DMA))) {
199 		device_free(dev);
200 
201 		dev->seq = -1;
202 		dev->flags &= ~DM_FLAG_ACTIVATED;
203 	}
204 
205 	return ret;
206 
207 err_remove:
208 	/* We can't put the children back */
209 	dm_warn("%s: Device '%s' failed to remove, but children are gone\n",
210 		__func__, dev->name);
211 err:
212 	ret = uclass_post_probe_device(dev);
213 	if (ret) {
214 		dm_warn("%s: Device '%s' failed to post_probe on error path\n",
215 			__func__, dev->name);
216 	}
217 
218 	return ret;
219 }
220