xref: /linux/drivers/firmware/dmi-id.c (revision 8b4a40809e5330c9da5d20107d693d92d73b31dc)
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/autoconf.h>
15 
16 #define DEFINE_DMI_ATTR(_name, _mode, _show)		\
17 static struct device_attribute sys_dmi_##_name##_attr =	\
18 	__ATTR(_name, _mode, _show, NULL);
19 
20 #define DEFINE_DMI_ATTR_WITH_SHOW(_name, _mode, _field)			\
21 static ssize_t sys_dmi_##_name##_show(struct device *dev,		\
22 				      struct device_attribute *attr,	\
23 				      char *page)			\
24 {									\
25 	ssize_t len;							\
26 	len = scnprintf(page, PAGE_SIZE, "%s\n", dmi_get_system_info(_field)); \
27 	page[len-1] = '\n';						\
28 	return len;							\
29 }									\
30 DEFINE_DMI_ATTR(_name, _mode, sys_dmi_##_name##_show);
31 
32 DEFINE_DMI_ATTR_WITH_SHOW(bios_vendor,		0444, DMI_BIOS_VENDOR);
33 DEFINE_DMI_ATTR_WITH_SHOW(bios_version,		0444, DMI_BIOS_VERSION);
34 DEFINE_DMI_ATTR_WITH_SHOW(bios_date,		0444, DMI_BIOS_DATE);
35 DEFINE_DMI_ATTR_WITH_SHOW(sys_vendor,		0444, DMI_SYS_VENDOR);
36 DEFINE_DMI_ATTR_WITH_SHOW(product_name,		0444, DMI_PRODUCT_NAME);
37 DEFINE_DMI_ATTR_WITH_SHOW(product_version,	0444, DMI_PRODUCT_VERSION);
38 DEFINE_DMI_ATTR_WITH_SHOW(product_serial,	0400, DMI_PRODUCT_SERIAL);
39 DEFINE_DMI_ATTR_WITH_SHOW(product_uuid,		0400, DMI_PRODUCT_UUID);
40 DEFINE_DMI_ATTR_WITH_SHOW(board_vendor,		0444, DMI_BOARD_VENDOR);
41 DEFINE_DMI_ATTR_WITH_SHOW(board_name,		0444, DMI_BOARD_NAME);
42 DEFINE_DMI_ATTR_WITH_SHOW(board_version,	0444, DMI_BOARD_VERSION);
43 DEFINE_DMI_ATTR_WITH_SHOW(board_serial,		0400, DMI_BOARD_SERIAL);
44 DEFINE_DMI_ATTR_WITH_SHOW(board_asset_tag,	0444, DMI_BOARD_ASSET_TAG);
45 DEFINE_DMI_ATTR_WITH_SHOW(chassis_vendor,	0444, DMI_CHASSIS_VENDOR);
46 DEFINE_DMI_ATTR_WITH_SHOW(chassis_type,		0444, DMI_CHASSIS_TYPE);
47 DEFINE_DMI_ATTR_WITH_SHOW(chassis_version,	0444, DMI_CHASSIS_VERSION);
48 DEFINE_DMI_ATTR_WITH_SHOW(chassis_serial,	0400, DMI_CHASSIS_SERIAL);
49 DEFINE_DMI_ATTR_WITH_SHOW(chassis_asset_tag,	0444, DMI_CHASSIS_ASSET_TAG);
50 
51 static void ascii_filter(char *d, const char *s)
52 {
53 	/* Filter out characters we don't want to see in the modalias string */
54 	for (; *s; s++)
55 		if (*s > ' ' && *s < 127 && *s != ':')
56 			*(d++) = *s;
57 
58 	*d = 0;
59 }
60 
61 static ssize_t get_modalias(char *buffer, size_t buffer_size)
62 {
63 	static const struct mafield {
64 		const char *prefix;
65 		int field;
66 	} fields[] = {
67 		{ "bvn", DMI_BIOS_VENDOR },
68 		{ "bvr", DMI_BIOS_VERSION },
69 		{ "bd",  DMI_BIOS_DATE },
70 		{ "svn", DMI_SYS_VENDOR },
71 		{ "pn",  DMI_PRODUCT_NAME },
72 		{ "pvr", DMI_PRODUCT_VERSION },
73 		{ "rvn", DMI_BOARD_VENDOR },
74 		{ "rn",  DMI_BOARD_NAME },
75 		{ "rvr", DMI_BOARD_VERSION },
76 		{ "cvn", DMI_CHASSIS_VENDOR },
77 		{ "ct",  DMI_CHASSIS_TYPE },
78 		{ "cvr", DMI_CHASSIS_VERSION },
79 		{ NULL,  DMI_NONE }
80 	};
81 
82 	ssize_t l, left;
83 	char *p;
84 	const struct mafield *f;
85 
86 	strcpy(buffer, "dmi");
87 	p = buffer + 3; left = buffer_size - 4;
88 
89 	for (f = fields; f->prefix && left > 0; f++) {
90 		const char *c;
91 		char *t;
92 
93 		c = dmi_get_system_info(f->field);
94 		if (!c)
95 			continue;
96 
97 		t = kmalloc(strlen(c) + 1, GFP_KERNEL);
98 		if (!t)
99 			break;
100 		ascii_filter(t, c);
101 		l = scnprintf(p, left, ":%s%s", f->prefix, t);
102 		kfree(t);
103 
104 		p += l;
105 		left -= l;
106 	}
107 
108 	p[0] = ':';
109 	p[1] = 0;
110 
111 	return p - buffer + 1;
112 }
113 
114 static ssize_t sys_dmi_modalias_show(struct device *dev,
115 				     struct device_attribute *attr, char *page)
116 {
117 	ssize_t r;
118 	r = get_modalias(page, PAGE_SIZE-1);
119 	page[r] = '\n';
120 	page[r+1] = 0;
121 	return r+1;
122 }
123 
124 DEFINE_DMI_ATTR(modalias, 0444, sys_dmi_modalias_show);
125 
126 static struct attribute *sys_dmi_attributes[DMI_STRING_MAX+2];
127 
128 static struct attribute_group sys_dmi_attribute_group = {
129 	.attrs = sys_dmi_attributes,
130 };
131 
132 static struct attribute_group* sys_dmi_attribute_groups[] = {
133 	&sys_dmi_attribute_group,
134 	NULL
135 };
136 
137 static int dmi_dev_uevent(struct device *dev, char **envp,
138 			    int num_envp, char *buffer, int buffer_size)
139 {
140 	strcpy(buffer, "MODALIAS=");
141 	get_modalias(buffer+9, buffer_size-9);
142 	envp[0] = buffer;
143 	envp[1] = NULL;
144 
145 	return 0;
146 }
147 
148 static struct class dmi_class = {
149 	.name = "dmi",
150 	.dev_release = (void(*)(struct device *)) kfree,
151 	.dev_uevent = dmi_dev_uevent,
152 };
153 
154 static struct device *dmi_dev;
155 
156 /* Initialization */
157 
158 #define ADD_DMI_ATTR(_name, _field) \
159 	if (dmi_get_system_info(_field)) \
160 		sys_dmi_attributes[i++] = & sys_dmi_##_name##_attr.attr;
161 
162 extern int dmi_available;
163 
164 static int __init dmi_id_init(void)
165 {
166 	int ret, i;
167 
168 	if (!dmi_available)
169 		return -ENODEV;
170 
171 	/* Not necessarily all DMI fields are available on all
172 	 * systems, hence let's built an attribute table of just
173 	 * what's available */
174 	i = 0;
175 	ADD_DMI_ATTR(bios_vendor,       DMI_BIOS_VENDOR);
176 	ADD_DMI_ATTR(bios_version,      DMI_BIOS_VERSION);
177 	ADD_DMI_ATTR(bios_date,         DMI_BIOS_DATE);
178 	ADD_DMI_ATTR(sys_vendor,        DMI_SYS_VENDOR);
179 	ADD_DMI_ATTR(product_name,      DMI_PRODUCT_NAME);
180 	ADD_DMI_ATTR(product_version,   DMI_PRODUCT_VERSION);
181 	ADD_DMI_ATTR(product_serial,    DMI_PRODUCT_SERIAL);
182 	ADD_DMI_ATTR(product_uuid,      DMI_PRODUCT_UUID);
183 	ADD_DMI_ATTR(board_vendor,      DMI_BOARD_VENDOR);
184 	ADD_DMI_ATTR(board_name,        DMI_BOARD_NAME);
185 	ADD_DMI_ATTR(board_version,     DMI_BOARD_VERSION);
186 	ADD_DMI_ATTR(board_serial,      DMI_BOARD_SERIAL);
187 	ADD_DMI_ATTR(board_asset_tag,   DMI_BOARD_ASSET_TAG);
188 	ADD_DMI_ATTR(chassis_vendor,    DMI_CHASSIS_VENDOR);
189 	ADD_DMI_ATTR(chassis_type,      DMI_CHASSIS_TYPE);
190 	ADD_DMI_ATTR(chassis_version,   DMI_CHASSIS_VERSION);
191 	ADD_DMI_ATTR(chassis_serial,    DMI_CHASSIS_SERIAL);
192 	ADD_DMI_ATTR(chassis_asset_tag, DMI_CHASSIS_ASSET_TAG);
193 	sys_dmi_attributes[i++] = &sys_dmi_modalias_attr.attr;
194 
195 	ret = class_register(&dmi_class);
196 	if (ret)
197 		return ret;
198 
199 	dmi_dev = kzalloc(sizeof(*dmi_dev), GFP_KERNEL);
200 	if (!dmi_dev) {
201 		ret = -ENOMEM;
202 		goto fail_class_unregister;
203 	}
204 
205 	dmi_dev->class = &dmi_class;
206 	strcpy(dmi_dev->bus_id, "id");
207 	dmi_dev->groups = sys_dmi_attribute_groups;
208 
209 	ret = device_register(dmi_dev);
210 	if (ret)
211 		goto fail_class_unregister;
212 
213 	return 0;
214 
215 fail_class_unregister:
216 
217 	class_unregister(&dmi_class);
218 
219 	return ret;
220 }
221 
222 arch_initcall(dmi_id_init);
223