1 #include <linux/string.h>
2 #include <linux/kernel.h>
3 #include <linux/of.h>
4 #include <linux/of_device.h>
5 #include <linux/init.h>
6 #include <linux/module.h>
7 #include <linux/mod_devicetable.h>
8 #include <linux/slab.h>
9
10 #include <asm/errno.h>
11
12 /**
13 * of_match_device - Tell if a struct device matches an of_device_id list
14 * @ids: array of of device match structures to search in
15 * @dev: the of device structure to match against
16 *
17 * Used by a driver to check whether an platform_device present in the
18 * system is in its list of supported devices.
19 */
of_match_device(const struct of_device_id * matches,const struct device * dev)20 const struct of_device_id *of_match_device(const struct of_device_id *matches,
21 const struct device *dev)
22 {
23 if ((!matches) || (!dev->of_node))
24 return NULL;
25 return of_match_node(matches, dev->of_node);
26 }
27 EXPORT_SYMBOL(of_match_device);
28
of_dev_get(struct platform_device * dev)29 struct platform_device *of_dev_get(struct platform_device *dev)
30 {
31 struct device *tmp;
32
33 if (!dev)
34 return NULL;
35 tmp = get_device(&dev->dev);
36 if (tmp)
37 return to_platform_device(tmp);
38 else
39 return NULL;
40 }
41 EXPORT_SYMBOL(of_dev_get);
42
of_dev_put(struct platform_device * dev)43 void of_dev_put(struct platform_device *dev)
44 {
45 if (dev)
46 put_device(&dev->dev);
47 }
48 EXPORT_SYMBOL(of_dev_put);
49
of_device_add(struct platform_device * ofdev)50 int of_device_add(struct platform_device *ofdev)
51 {
52 BUG_ON(ofdev->dev.of_node == NULL);
53
54 /* name and id have to be set so that the platform bus doesn't get
55 * confused on matching */
56 ofdev->name = dev_name(&ofdev->dev);
57 ofdev->id = -1;
58
59 /* device_add will assume that this device is on the same node as
60 * the parent. If there is no parent defined, set the node
61 * explicitly */
62 if (!ofdev->dev.parent)
63 set_dev_node(&ofdev->dev, of_node_to_nid(ofdev->dev.of_node));
64
65 return device_add(&ofdev->dev);
66 }
67
of_device_register(struct platform_device * pdev)68 int of_device_register(struct platform_device *pdev)
69 {
70 device_initialize(&pdev->dev);
71 return of_device_add(pdev);
72 }
73 EXPORT_SYMBOL(of_device_register);
74
of_device_unregister(struct platform_device * ofdev)75 void of_device_unregister(struct platform_device *ofdev)
76 {
77 device_unregister(&ofdev->dev);
78 }
79 EXPORT_SYMBOL(of_device_unregister);
80
of_device_get_modalias(struct device * dev,char * str,ssize_t len)81 ssize_t of_device_get_modalias(struct device *dev, char *str, ssize_t len)
82 {
83 const char *compat;
84 int cplen, i;
85 ssize_t tsize, csize, repend;
86
87 /* Name & Type */
88 csize = snprintf(str, len, "of:N%sT%s", dev->of_node->name,
89 dev->of_node->type);
90
91 /* Get compatible property if any */
92 compat = of_get_property(dev->of_node, "compatible", &cplen);
93 if (!compat)
94 return csize;
95
96 /* Find true end (we tolerate multiple \0 at the end */
97 for (i = (cplen - 1); i >= 0 && !compat[i]; i--)
98 cplen--;
99 if (!cplen)
100 return csize;
101 cplen++;
102
103 /* Check space (need cplen+1 chars including final \0) */
104 tsize = csize + cplen;
105 repend = tsize;
106
107 if (csize >= len) /* @ the limit, all is already filled */
108 return tsize;
109
110 if (tsize >= len) { /* limit compat list */
111 cplen = len - csize - 1;
112 repend = len;
113 }
114
115 /* Copy and do char replacement */
116 memcpy(&str[csize + 1], compat, cplen);
117 for (i = csize; i < repend; i++) {
118 char c = str[i];
119 if (c == '\0')
120 str[i] = 'C';
121 else if (c == ' ')
122 str[i] = '_';
123 }
124
125 return tsize;
126 }
127
128 /**
129 * of_device_uevent - Display OF related uevent information
130 */
of_device_uevent(struct device * dev,struct kobj_uevent_env * env)131 void of_device_uevent(struct device *dev, struct kobj_uevent_env *env)
132 {
133 const char *compat;
134 int seen = 0, cplen, sl;
135
136 if ((!dev) || (!dev->of_node))
137 return;
138
139 add_uevent_var(env, "OF_NAME=%s", dev->of_node->name);
140 add_uevent_var(env, "OF_FULLNAME=%s", dev->of_node->full_name);
141 if (dev->of_node->type && strcmp("<NULL>", dev->of_node->type) != 0)
142 add_uevent_var(env, "OF_TYPE=%s", dev->of_node->type);
143
144 /* Since the compatible field can contain pretty much anything
145 * it's not really legal to split it out with commas. We split it
146 * up using a number of environment variables instead. */
147 compat = of_get_property(dev->of_node, "compatible", &cplen);
148 while (compat && *compat && cplen > 0) {
149 add_uevent_var(env, "OF_COMPATIBLE_%d=%s", seen, compat);
150 sl = strlen(compat) + 1;
151 compat += sl;
152 cplen -= sl;
153 seen++;
154 }
155 add_uevent_var(env, "OF_COMPATIBLE_N=%d", seen);
156 }
157
of_device_uevent_modalias(struct device * dev,struct kobj_uevent_env * env)158 int of_device_uevent_modalias(struct device *dev, struct kobj_uevent_env *env)
159 {
160 int sl;
161
162 if ((!dev) || (!dev->of_node))
163 return -ENODEV;
164
165 /* Devicetree modalias is tricky, we add it in 2 steps */
166 if (add_uevent_var(env, "MODALIAS="))
167 return -ENOMEM;
168
169 sl = of_device_get_modalias(dev, &env->buf[env->buflen-1],
170 sizeof(env->buf) - env->buflen);
171 if (sl >= (sizeof(env->buf) - env->buflen))
172 return -ENOMEM;
173 env->buflen += sl;
174
175 return 0;
176 }
177