xref: /linux/drivers/firmware/dmi-id.c (revision 93d90ad708b8da6efc0e487b66111aa9db7f70c7)
1 /*
2  * Export SMBIOS/DMI info via sysfs to userspace
3  *
4  * Copyright 2007, Lennart Poettering
5  *
6  * Licensed under GPLv2
7  */
8 
9 #include <linux/module.h>
10 #include <linux/kernel.h>
11 #include <linux/init.h>
12 #include <linux/dmi.h>
13 #include <linux/device.h>
14 #include <linux/slab.h>
15 
16 struct dmi_device_attribute{
17 	struct device_attribute dev_attr;
18 	int field;
19 };
20 #define to_dmi_dev_attr(_dev_attr) \
21 	container_of(_dev_attr, struct dmi_device_attribute, dev_attr)
22 
23 static ssize_t sys_dmi_field_show(struct device *dev,
24 				  struct device_attribute *attr,
25 				  char *page)
26 {
27 	int field = to_dmi_dev_attr(attr)->field;
28 	ssize_t len;
29 	len = scnprintf(page, PAGE_SIZE, "%s\n", dmi_get_system_info(field));
30 	page[len-1] = '\n';
31 	return len;
32 }
33 
34 #define DMI_ATTR(_name, _mode, _show, _field)			\
35 	{ .dev_attr = __ATTR(_name, _mode, _show, NULL),	\
36 	  .field = _field }
37 
38 #define DEFINE_DMI_ATTR_WITH_SHOW(_name, _mode, _field)		\
39 static struct dmi_device_attribute sys_dmi_##_name##_attr =	\
40 	DMI_ATTR(_name, _mode, sys_dmi_field_show, _field);
41 
42 DEFINE_DMI_ATTR_WITH_SHOW(bios_vendor,		0444, DMI_BIOS_VENDOR);
43 DEFINE_DMI_ATTR_WITH_SHOW(bios_version,		0444, DMI_BIOS_VERSION);
44 DEFINE_DMI_ATTR_WITH_SHOW(bios_date,		0444, DMI_BIOS_DATE);
45 DEFINE_DMI_ATTR_WITH_SHOW(sys_vendor,		0444, DMI_SYS_VENDOR);
46 DEFINE_DMI_ATTR_WITH_SHOW(product_name,		0444, DMI_PRODUCT_NAME);
47 DEFINE_DMI_ATTR_WITH_SHOW(product_version,	0444, DMI_PRODUCT_VERSION);
48 DEFINE_DMI_ATTR_WITH_SHOW(product_serial,	0400, DMI_PRODUCT_SERIAL);
49 DEFINE_DMI_ATTR_WITH_SHOW(product_uuid,		0400, DMI_PRODUCT_UUID);
50 DEFINE_DMI_ATTR_WITH_SHOW(board_vendor,		0444, DMI_BOARD_VENDOR);
51 DEFINE_DMI_ATTR_WITH_SHOW(board_name,		0444, DMI_BOARD_NAME);
52 DEFINE_DMI_ATTR_WITH_SHOW(board_version,	0444, DMI_BOARD_VERSION);
53 DEFINE_DMI_ATTR_WITH_SHOW(board_serial,		0400, DMI_BOARD_SERIAL);
54 DEFINE_DMI_ATTR_WITH_SHOW(board_asset_tag,	0444, DMI_BOARD_ASSET_TAG);
55 DEFINE_DMI_ATTR_WITH_SHOW(chassis_vendor,	0444, DMI_CHASSIS_VENDOR);
56 DEFINE_DMI_ATTR_WITH_SHOW(chassis_type,		0444, DMI_CHASSIS_TYPE);
57 DEFINE_DMI_ATTR_WITH_SHOW(chassis_version,	0444, DMI_CHASSIS_VERSION);
58 DEFINE_DMI_ATTR_WITH_SHOW(chassis_serial,	0400, DMI_CHASSIS_SERIAL);
59 DEFINE_DMI_ATTR_WITH_SHOW(chassis_asset_tag,	0444, DMI_CHASSIS_ASSET_TAG);
60 
61 static void ascii_filter(char *d, const char *s)
62 {
63 	/* Filter out characters we don't want to see in the modalias string */
64 	for (; *s; s++)
65 		if (*s > ' ' && *s < 127 && *s != ':')
66 			*(d++) = *s;
67 
68 	*d = 0;
69 }
70 
71 static ssize_t get_modalias(char *buffer, size_t buffer_size)
72 {
73 	static const struct mafield {
74 		const char *prefix;
75 		int field;
76 	} fields[] = {
77 		{ "bvn", DMI_BIOS_VENDOR },
78 		{ "bvr", DMI_BIOS_VERSION },
79 		{ "bd",  DMI_BIOS_DATE },
80 		{ "svn", DMI_SYS_VENDOR },
81 		{ "pn",  DMI_PRODUCT_NAME },
82 		{ "pvr", DMI_PRODUCT_VERSION },
83 		{ "rvn", DMI_BOARD_VENDOR },
84 		{ "rn",  DMI_BOARD_NAME },
85 		{ "rvr", DMI_BOARD_VERSION },
86 		{ "cvn", DMI_CHASSIS_VENDOR },
87 		{ "ct",  DMI_CHASSIS_TYPE },
88 		{ "cvr", DMI_CHASSIS_VERSION },
89 		{ NULL,  DMI_NONE }
90 	};
91 
92 	ssize_t l, left;
93 	char *p;
94 	const struct mafield *f;
95 
96 	strcpy(buffer, "dmi");
97 	p = buffer + 3; left = buffer_size - 4;
98 
99 	for (f = fields; f->prefix && left > 0; f++) {
100 		const char *c;
101 		char *t;
102 
103 		c = dmi_get_system_info(f->field);
104 		if (!c)
105 			continue;
106 
107 		t = kmalloc(strlen(c) + 1, GFP_KERNEL);
108 		if (!t)
109 			break;
110 		ascii_filter(t, c);
111 		l = scnprintf(p, left, ":%s%s", f->prefix, t);
112 		kfree(t);
113 
114 		p += l;
115 		left -= l;
116 	}
117 
118 	p[0] = ':';
119 	p[1] = 0;
120 
121 	return p - buffer + 1;
122 }
123 
124 static ssize_t sys_dmi_modalias_show(struct device *dev,
125 				     struct device_attribute *attr, char *page)
126 {
127 	ssize_t r;
128 	r = get_modalias(page, PAGE_SIZE-1);
129 	page[r] = '\n';
130 	page[r+1] = 0;
131 	return r+1;
132 }
133 
134 static struct device_attribute sys_dmi_modalias_attr =
135 	__ATTR(modalias, 0444, sys_dmi_modalias_show, NULL);
136 
137 static struct attribute *sys_dmi_attributes[DMI_STRING_MAX+2];
138 
139 static struct attribute_group sys_dmi_attribute_group = {
140 	.attrs = sys_dmi_attributes,
141 };
142 
143 static const struct attribute_group* sys_dmi_attribute_groups[] = {
144 	&sys_dmi_attribute_group,
145 	NULL
146 };
147 
148 static int dmi_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
149 {
150 	ssize_t len;
151 
152 	if (add_uevent_var(env, "MODALIAS="))
153 		return -ENOMEM;
154 	len = get_modalias(&env->buf[env->buflen - 1],
155 			   sizeof(env->buf) - env->buflen);
156 	if (len >= (sizeof(env->buf) - env->buflen))
157 		return -ENOMEM;
158 	env->buflen += len;
159 	return 0;
160 }
161 
162 static struct class dmi_class = {
163 	.name = "dmi",
164 	.dev_release = (void(*)(struct device *)) kfree,
165 	.dev_uevent = dmi_dev_uevent,
166 };
167 
168 static struct device *dmi_dev;
169 
170 /* Initialization */
171 
172 #define ADD_DMI_ATTR(_name, _field) \
173 	if (dmi_get_system_info(_field)) \
174 		sys_dmi_attributes[i++] = &sys_dmi_##_name##_attr.dev_attr.attr;
175 
176 /* In a separate function to keep gcc 3.2 happy - do NOT merge this in
177    dmi_id_init! */
178 static void __init dmi_id_init_attr_table(void)
179 {
180 	int i;
181 
182 	/* Not necessarily all DMI fields are available on all
183 	 * systems, hence let's built an attribute table of just
184 	 * what's available */
185 	i = 0;
186 	ADD_DMI_ATTR(bios_vendor,       DMI_BIOS_VENDOR);
187 	ADD_DMI_ATTR(bios_version,      DMI_BIOS_VERSION);
188 	ADD_DMI_ATTR(bios_date,         DMI_BIOS_DATE);
189 	ADD_DMI_ATTR(sys_vendor,        DMI_SYS_VENDOR);
190 	ADD_DMI_ATTR(product_name,      DMI_PRODUCT_NAME);
191 	ADD_DMI_ATTR(product_version,   DMI_PRODUCT_VERSION);
192 	ADD_DMI_ATTR(product_serial,    DMI_PRODUCT_SERIAL);
193 	ADD_DMI_ATTR(product_uuid,      DMI_PRODUCT_UUID);
194 	ADD_DMI_ATTR(board_vendor,      DMI_BOARD_VENDOR);
195 	ADD_DMI_ATTR(board_name,        DMI_BOARD_NAME);
196 	ADD_DMI_ATTR(board_version,     DMI_BOARD_VERSION);
197 	ADD_DMI_ATTR(board_serial,      DMI_BOARD_SERIAL);
198 	ADD_DMI_ATTR(board_asset_tag,   DMI_BOARD_ASSET_TAG);
199 	ADD_DMI_ATTR(chassis_vendor,    DMI_CHASSIS_VENDOR);
200 	ADD_DMI_ATTR(chassis_type,      DMI_CHASSIS_TYPE);
201 	ADD_DMI_ATTR(chassis_version,   DMI_CHASSIS_VERSION);
202 	ADD_DMI_ATTR(chassis_serial,    DMI_CHASSIS_SERIAL);
203 	ADD_DMI_ATTR(chassis_asset_tag, DMI_CHASSIS_ASSET_TAG);
204 	sys_dmi_attributes[i++] = &sys_dmi_modalias_attr.attr;
205 }
206 
207 static int __init dmi_id_init(void)
208 {
209 	int ret;
210 
211 	if (!dmi_available)
212 		return -ENODEV;
213 
214 	dmi_id_init_attr_table();
215 
216 	ret = class_register(&dmi_class);
217 	if (ret)
218 		return ret;
219 
220 	dmi_dev = kzalloc(sizeof(*dmi_dev), GFP_KERNEL);
221 	if (!dmi_dev) {
222 		ret = -ENOMEM;
223 		goto fail_class_unregister;
224 	}
225 
226 	dmi_dev->class = &dmi_class;
227 	dev_set_name(dmi_dev, "id");
228 	dmi_dev->groups = sys_dmi_attribute_groups;
229 
230 	ret = device_register(dmi_dev);
231 	if (ret)
232 		goto fail_free_dmi_dev;
233 
234 	return 0;
235 
236 fail_free_dmi_dev:
237 	kfree(dmi_dev);
238 fail_class_unregister:
239 
240 	class_unregister(&dmi_class);
241 
242 	return ret;
243 }
244 
245 arch_initcall(dmi_id_init);
246