xref: /openbmc/u-boot/drivers/core/device-remove.c (revision 93322749)
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 	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 	ret = uclass_unbind_device(dev);
92 	if (ret)
93 		return ret;
94 
95 	if (dev->parent)
96 		list_del(&dev->sibling_node);
97 	free(dev);
98 
99 	return 0;
100 }
101 
102 /**
103  * device_free() - Free memory buffers allocated by a device
104  * @dev:	Device that is to be started
105  */
106 void device_free(struct udevice *dev)
107 {
108 	int size;
109 
110 	if (dev->driver->priv_auto_alloc_size) {
111 		free(dev->priv);
112 		dev->priv = NULL;
113 	}
114 	if (dev->flags & DM_FLAG_ALLOC_PDATA) {
115 		free(dev->platdata);
116 		dev->platdata = NULL;
117 	}
118 	size = dev->uclass->uc_drv->per_device_auto_alloc_size;
119 	if (size) {
120 		free(dev->uclass_priv);
121 		dev->uclass_priv = NULL;
122 	}
123 	if (dev->parent) {
124 		size = dev->parent->driver->per_child_auto_alloc_size;
125 		if (size) {
126 			free(dev->parent_priv);
127 			dev->parent_priv = NULL;
128 		}
129 	}
130 }
131 
132 int device_remove(struct udevice *dev)
133 {
134 	struct driver *drv;
135 	int ret;
136 
137 	if (!dev)
138 		return -EINVAL;
139 
140 	if (!(dev->flags & DM_FLAG_ACTIVATED))
141 		return 0;
142 
143 	drv = dev->driver;
144 	assert(drv);
145 
146 	ret = uclass_pre_remove_device(dev);
147 	if (ret)
148 		return ret;
149 
150 	ret = device_chld_remove(dev);
151 	if (ret)
152 		goto err;
153 
154 	if (drv->remove) {
155 		ret = drv->remove(dev);
156 		if (ret)
157 			goto err_remove;
158 	}
159 
160 	if (dev->parent && dev->parent->driver->child_post_remove) {
161 		ret = dev->parent->driver->child_post_remove(dev);
162 		if (ret) {
163 			dm_warn("%s: Device '%s' failed child_post_remove()",
164 				__func__, dev->name);
165 		}
166 	}
167 
168 	device_free(dev);
169 
170 	dev->seq = -1;
171 	dev->flags &= ~DM_FLAG_ACTIVATED;
172 
173 	return ret;
174 
175 err_remove:
176 	/* We can't put the children back */
177 	dm_warn("%s: Device '%s' failed to remove, but children are gone\n",
178 		__func__, dev->name);
179 err:
180 	ret = uclass_post_probe_device(dev);
181 	if (ret) {
182 		dm_warn("%s: Device '%s' failed to post_probe on error path\n",
183 			__func__, dev->name);
184 	}
185 
186 	return ret;
187 }
188