xref: /openbmc/u-boot/drivers/core/device-remove.c (revision c7b9686d)
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  * @return 0 on success, -ve on error
50  */
51 static int device_chld_remove(struct udevice *dev)
52 {
53 	struct udevice *pos, *n;
54 	int ret;
55 
56 	assert(dev);
57 
58 	list_for_each_entry_safe(pos, n, &dev->child_head, sibling_node) {
59 		ret = device_remove(pos);
60 		if (ret)
61 			return ret;
62 	}
63 
64 	return 0;
65 }
66 
67 int device_unbind(struct udevice *dev)
68 {
69 	const struct driver *drv;
70 	int ret;
71 
72 	if (!dev)
73 		return -EINVAL;
74 
75 	if (dev->flags & DM_FLAG_ACTIVATED)
76 		return -EINVAL;
77 
78 	if (!(dev->flags & DM_FLAG_BOUND))
79 		return -EINVAL;
80 
81 	drv = dev->driver;
82 	assert(drv);
83 
84 	if (drv->unbind) {
85 		ret = drv->unbind(dev);
86 		if (ret)
87 			return ret;
88 	}
89 
90 	ret = device_chld_unbind(dev);
91 	if (ret)
92 		return ret;
93 
94 	if (dev->flags & DM_FLAG_ALLOC_PDATA) {
95 		free(dev->platdata);
96 		dev->platdata = NULL;
97 	}
98 	if (dev->flags & DM_FLAG_ALLOC_UCLASS_PDATA) {
99 		free(dev->uclass_platdata);
100 		dev->uclass_platdata = NULL;
101 	}
102 	if (dev->flags & DM_FLAG_ALLOC_PARENT_PDATA) {
103 		free(dev->parent_platdata);
104 		dev->parent_platdata = NULL;
105 	}
106 	ret = uclass_unbind_device(dev);
107 	if (ret)
108 		return ret;
109 
110 	if (dev->parent)
111 		list_del(&dev->sibling_node);
112 
113 	devres_release_all(dev);
114 
115 	free(dev);
116 
117 	return 0;
118 }
119 
120 /**
121  * device_free() - Free memory buffers allocated by a device
122  * @dev:	Device that is to be started
123  */
124 void device_free(struct udevice *dev)
125 {
126 	int size;
127 
128 	if (dev->driver->priv_auto_alloc_size) {
129 		free(dev->priv);
130 		dev->priv = NULL;
131 	}
132 	size = dev->uclass->uc_drv->per_device_auto_alloc_size;
133 	if (size) {
134 		free(dev->uclass_priv);
135 		dev->uclass_priv = NULL;
136 	}
137 	if (dev->parent) {
138 		size = dev->parent->driver->per_child_auto_alloc_size;
139 		if (!size) {
140 			size = dev->parent->uclass->uc_drv->
141 					per_child_auto_alloc_size;
142 		}
143 		if (size) {
144 			free(dev->parent_priv);
145 			dev->parent_priv = NULL;
146 		}
147 	}
148 
149 	devres_release_probe(dev);
150 }
151 
152 int device_remove(struct udevice *dev)
153 {
154 	const struct driver *drv;
155 	int ret;
156 
157 	if (!dev)
158 		return -EINVAL;
159 
160 	if (!(dev->flags & DM_FLAG_ACTIVATED))
161 		return 0;
162 
163 	drv = dev->driver;
164 	assert(drv);
165 
166 	ret = uclass_pre_remove_device(dev);
167 	if (ret)
168 		return ret;
169 
170 	ret = device_chld_remove(dev);
171 	if (ret)
172 		goto err;
173 
174 	if (drv->remove) {
175 		ret = drv->remove(dev);
176 		if (ret)
177 			goto err_remove;
178 	}
179 
180 	if (dev->parent && dev->parent->driver->child_post_remove) {
181 		ret = dev->parent->driver->child_post_remove(dev);
182 		if (ret) {
183 			dm_warn("%s: Device '%s' failed child_post_remove()",
184 				__func__, dev->name);
185 		}
186 	}
187 
188 	device_free(dev);
189 
190 	dev->seq = -1;
191 	dev->flags &= ~DM_FLAG_ACTIVATED;
192 
193 	return ret;
194 
195 err_remove:
196 	/* We can't put the children back */
197 	dm_warn("%s: Device '%s' failed to remove, but children are gone\n",
198 		__func__, dev->name);
199 err:
200 	ret = uclass_post_probe_device(dev);
201 	if (ret) {
202 		dm_warn("%s: Device '%s' failed to post_probe on error path\n",
203 			__func__, dev->name);
204 	}
205 
206 	return ret;
207 }
208