xref: /openbmc/u-boot/drivers/core/device-remove.c (revision 4a34e4b8)
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 	drv = dev->driver;
79 	assert(drv);
80 
81 	if (drv->unbind) {
82 		ret = drv->unbind(dev);
83 		if (ret)
84 			return ret;
85 	}
86 
87 	ret = device_chld_unbind(dev);
88 	if (ret)
89 		return ret;
90 
91 	if (dev->flags & DM_FLAG_ALLOC_PDATA) {
92 		free(dev->platdata);
93 		dev->platdata = NULL;
94 	}
95 	if (dev->flags & DM_FLAG_ALLOC_UCLASS_PDATA) {
96 		free(dev->uclass_platdata);
97 		dev->uclass_platdata = NULL;
98 	}
99 	if (dev->flags & DM_FLAG_ALLOC_PARENT_PDATA) {
100 		free(dev->parent_platdata);
101 		dev->parent_platdata = NULL;
102 	}
103 	ret = uclass_unbind_device(dev);
104 	if (ret)
105 		return ret;
106 
107 	if (dev->parent)
108 		list_del(&dev->sibling_node);
109 	free(dev);
110 
111 	return 0;
112 }
113 
114 /**
115  * device_free() - Free memory buffers allocated by a device
116  * @dev:	Device that is to be started
117  */
118 void device_free(struct udevice *dev)
119 {
120 	int size;
121 
122 	if (dev->driver->priv_auto_alloc_size) {
123 		free(dev->priv);
124 		dev->priv = NULL;
125 	}
126 	size = dev->uclass->uc_drv->per_device_auto_alloc_size;
127 	if (size) {
128 		free(dev->uclass_priv);
129 		dev->uclass_priv = NULL;
130 	}
131 	if (dev->parent) {
132 		size = dev->parent->driver->per_child_auto_alloc_size;
133 		if (!size) {
134 			size = dev->parent->uclass->uc_drv->
135 					per_child_auto_alloc_size;
136 		}
137 		if (size) {
138 			free(dev->parent_priv);
139 			dev->parent_priv = NULL;
140 		}
141 	}
142 }
143 
144 int device_remove(struct udevice *dev)
145 {
146 	const struct driver *drv;
147 	int ret;
148 
149 	if (!dev)
150 		return -EINVAL;
151 
152 	if (!(dev->flags & DM_FLAG_ACTIVATED))
153 		return 0;
154 
155 	drv = dev->driver;
156 	assert(drv);
157 
158 	ret = uclass_pre_remove_device(dev);
159 	if (ret)
160 		return ret;
161 
162 	ret = device_chld_remove(dev);
163 	if (ret)
164 		goto err;
165 
166 	if (drv->remove) {
167 		ret = drv->remove(dev);
168 		if (ret)
169 			goto err_remove;
170 	}
171 
172 	if (dev->parent && dev->parent->driver->child_post_remove) {
173 		ret = dev->parent->driver->child_post_remove(dev);
174 		if (ret) {
175 			dm_warn("%s: Device '%s' failed child_post_remove()",
176 				__func__, dev->name);
177 		}
178 	}
179 
180 	device_free(dev);
181 
182 	dev->seq = -1;
183 	dev->flags &= ~DM_FLAG_ACTIVATED;
184 
185 	return ret;
186 
187 err_remove:
188 	/* We can't put the children back */
189 	dm_warn("%s: Device '%s' failed to remove, but children are gone\n",
190 		__func__, dev->name);
191 err:
192 	ret = uclass_post_probe_device(dev);
193 	if (ret) {
194 		dm_warn("%s: Device '%s' failed to post_probe on error path\n",
195 			__func__, dev->name);
196 	}
197 
198 	return ret;
199 }
200