aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/of/device.c
blob: f685e55e0717f611bf479f95d790675d6bb77bf5 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
#include <linux/string.h>
#include <linux/kernel.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/mod_devicetable.h>
#include <linux/slab.h>

#include <asm/errno.h>
#include "of_private.h"

/**
 * of_match_device - Tell if a struct device matches an of_device_id list
 * @ids: array of of device match structures to search in
 * @dev: the of device structure to match against
 *
 * Used by a driver to check whether an platform_device present in the
 * system is in its list of supported devices.
 */
const struct of_device_id *of_match_device(const struct of_device_id *matches,
					   const struct device *dev)
{
	if ((!matches) || (!dev->of_node))
		return NULL;
	return of_match_node(matches, dev->of_node);
}
EXPORT_SYMBOL(of_match_device);

struct platform_device *of_dev_get(struct platform_device *dev)
{
	struct device *tmp;

	if (!dev)
		return NULL;
	tmp = get_device(&dev->dev);
	if (tmp)
		return to_platform_device(tmp);
	else
		return NULL;
}
EXPORT_SYMBOL(of_dev_get);

void of_dev_put(struct platform_device *dev)
{
	if (dev)
		put_device(&dev->dev);
}
EXPORT_SYMBOL(of_dev_put);

int of_device_add(struct platform_device *ofdev)
{
	BUG_ON(ofdev->dev.of_node == NULL);

	/* name and id have to be set so that the platform bus doesn't get
	 * confused on matching */
	ofdev->name = dev_name(&ofdev->dev);
	ofdev->id = -1;

	/* device_add will assume that this device is on the same node as
	 * the parent. If there is no parent defined, set the node
	 * explicitly */
	if (!ofdev->dev.parent)
		set_dev_node(&ofdev->dev, of_node_to_nid(ofdev->dev.of_node));

	return device_add(&ofdev->dev);
}

int of_device_register(struct platform_device *pdev)
{
	device_initialize(&pdev->dev);
	return of_device_add(pdev);
}
EXPORT_SYMBOL(of_device_register);

void of_device_unregister(struct platform_device *ofdev)
{
	device_unregister(&ofdev->dev);
}
EXPORT_SYMBOL(of_device_unregister);

ssize_t of_device_get_modalias(struct device *dev, char *str, ssize_t len)
{
	const char *compat;
	int cplen, i;
	ssize_t tsize, csize, repend;

	/* Name & Type */
	csize = snprintf(str, len, "of:N%sT%s", dev->of_node->name,
			 dev->of_node->type);

	/* Get compatible property if any */
	compat = of_get_property(dev->of_node, "compatible", &cplen);
	if (!compat)
		return csize;

	/* Find true end (we tolerate multiple \0 at the end */
	for (i = (cplen - 1); i >= 0 && !compat[i]; i--)
		cplen--;
	if (!cplen)
		return csize;
	cplen++;

	/* Check space (need cplen+1 chars including final \0) */
	tsize = csize + cplen;
	repend = tsize;

	if (csize >= len)		/* @ the limit, all is already filled */
		return tsize;

	if (tsize >= len) {		/* limit compat list */
		cplen = len - csize - 1;
		repend = len;
	}

	/* Copy and do char replacement */
	memcpy(&str[csize + 1], compat, cplen);
	for (i = csize; i < repend; i++) {
		char c = str[i];
		if (c == '\0')
			str[i] = 'C';
		else if (c == ' ')
			str[i] = '_';
	}

	return tsize;
}

/**
 * of_device_uevent - Display OF related uevent information
 */
void of_device_uevent(struct device *dev, struct kobj_uevent_env *env)
{
	const char *compat;
	struct alias_prop *app;
	int seen = 0, cplen, sl;

	if ((!dev) || (!dev->of_node))
		return;

	add_uevent_var(env, "OF_NAME=%s", dev->of_node->name);
	add_uevent_var(env, "OF_FULLNAME=%s", dev->of_node->full_name);
	if (dev->of_node->type && strcmp("<NULL>", dev->of_node->type) != 0)
		add_uevent_var(env, "OF_TYPE=%s", dev->of_node->type);

	/* Since the compatible field can contain pretty much anything
	 * it's not really legal to split it out with commas. We split it
	 * up using a number of environment variables instead. */
	compat = of_get_property(dev->of_node, "compatible", &cplen);
	while (compat && *compat && cplen > 0) {
		add_uevent_var(env, "OF_COMPATIBLE_%d=%s", seen, compat);
		sl = strlen(compat) + 1;
		compat += sl;
		cplen -= sl;
		seen++;
	}
	add_uevent_var(env, "OF_COMPATIBLE_N=%d", seen);

	seen = 0;
	mutex_lock(&of_aliases_mutex);
	list_for_each_entry(app, &aliases_lookup, link) {
		if (dev->of_node == app->np) {
			add_uevent_var(env, "OF_ALIAS_%d=%s", seen,
				       app->alias);
			seen++;
		}
	}
	mutex_unlock(&of_aliases_mutex);
}

int of_device_uevent_modalias(struct device *dev, struct kobj_uevent_env *env)
{
	int sl;

	if ((!dev) || (!dev->of_node))
		return -ENODEV;

	/* Devicetree modalias is tricky, we add it in 2 steps */
	if (add_uevent_var(env, "MODALIAS="))
		return -ENOMEM;

	sl = of_device_get_modalias(dev, &env->buf[env->buflen-1],
				    sizeof(env->buf) - env->buflen);
	if (sl >= (sizeof(env->buf) - env->buflen))
		return -ENOMEM;
	env->buflen += sl;

	return 0;
}