xref: /openbmc/linux/drivers/firmware/dmi-id.c (revision a09d2831)
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 
15 struct dmi_device_attribute{
16 	struct device_attribute dev_attr;
17 	int field;
18 };
19 #define to_dmi_dev_attr(_dev_attr) \
20 	container_of(_dev_attr, struct dmi_device_attribute, dev_attr)
21 
22 static ssize_t sys_dmi_field_show(struct device *dev,
23 				  struct device_attribute *attr,
24 				  char *page)
25 {
26 	int field = to_dmi_dev_attr(attr)->field;
27 	ssize_t len;
28 	len = scnprintf(page, PAGE_SIZE, "%s\n", dmi_get_system_info(field));
29 	page[len-1] = '\n';
30 	return len;
31 }
32 
33 #define DMI_ATTR(_name, _mode, _show, _field)			\
34 	{ .dev_attr = __ATTR(_name, _mode, _show, NULL),	\
35 	  .field = _field }
36 
37 #define DEFINE_DMI_ATTR_WITH_SHOW(_name, _mode, _field)		\
38 static struct dmi_device_attribute sys_dmi_##_name##_attr =	\
39 	DMI_ATTR(_name, _mode, sys_dmi_field_show, _field);
40 
41 DEFINE_DMI_ATTR_WITH_SHOW(bios_vendor,		0444, DMI_BIOS_VENDOR);
42 DEFINE_DMI_ATTR_WITH_SHOW(bios_version,		0444, DMI_BIOS_VERSION);
43 DEFINE_DMI_ATTR_WITH_SHOW(bios_date,		0444, DMI_BIOS_DATE);
44 DEFINE_DMI_ATTR_WITH_SHOW(sys_vendor,		0444, DMI_SYS_VENDOR);
45 DEFINE_DMI_ATTR_WITH_SHOW(product_name,		0444, DMI_PRODUCT_NAME);
46 DEFINE_DMI_ATTR_WITH_SHOW(product_version,	0444, DMI_PRODUCT_VERSION);
47 DEFINE_DMI_ATTR_WITH_SHOW(product_serial,	0400, DMI_PRODUCT_SERIAL);
48 DEFINE_DMI_ATTR_WITH_SHOW(product_uuid,		0400, DMI_PRODUCT_UUID);
49 DEFINE_DMI_ATTR_WITH_SHOW(board_vendor,		0444, DMI_BOARD_VENDOR);
50 DEFINE_DMI_ATTR_WITH_SHOW(board_name,		0444, DMI_BOARD_NAME);
51 DEFINE_DMI_ATTR_WITH_SHOW(board_version,	0444, DMI_BOARD_VERSION);
52 DEFINE_DMI_ATTR_WITH_SHOW(board_serial,		0400, DMI_BOARD_SERIAL);
53 DEFINE_DMI_ATTR_WITH_SHOW(board_asset_tag,	0444, DMI_BOARD_ASSET_TAG);
54 DEFINE_DMI_ATTR_WITH_SHOW(chassis_vendor,	0444, DMI_CHASSIS_VENDOR);
55 DEFINE_DMI_ATTR_WITH_SHOW(chassis_type,		0444, DMI_CHASSIS_TYPE);
56 DEFINE_DMI_ATTR_WITH_SHOW(chassis_version,	0444, DMI_CHASSIS_VERSION);
57 DEFINE_DMI_ATTR_WITH_SHOW(chassis_serial,	0400, DMI_CHASSIS_SERIAL);
58 DEFINE_DMI_ATTR_WITH_SHOW(chassis_asset_tag,	0444, DMI_CHASSIS_ASSET_TAG);
59 
60 static void ascii_filter(char *d, const char *s)
61 {
62 	/* Filter out characters we don't want to see in the modalias string */
63 	for (; *s; s++)
64 		if (*s > ' ' && *s < 127 && *s != ':')
65 			*(d++) = *s;
66 
67 	*d = 0;
68 }
69 
70 static ssize_t get_modalias(char *buffer, size_t buffer_size)
71 {
72 	static const struct mafield {
73 		const char *prefix;
74 		int field;
75 	} fields[] = {
76 		{ "bvn", DMI_BIOS_VENDOR },
77 		{ "bvr", DMI_BIOS_VERSION },
78 		{ "bd",  DMI_BIOS_DATE },
79 		{ "svn", DMI_SYS_VENDOR },
80 		{ "pn",  DMI_PRODUCT_NAME },
81 		{ "pvr", DMI_PRODUCT_VERSION },
82 		{ "rvn", DMI_BOARD_VENDOR },
83 		{ "rn",  DMI_BOARD_NAME },
84 		{ "rvr", DMI_BOARD_VERSION },
85 		{ "cvn", DMI_CHASSIS_VENDOR },
86 		{ "ct",  DMI_CHASSIS_TYPE },
87 		{ "cvr", DMI_CHASSIS_VERSION },
88 		{ NULL,  DMI_NONE }
89 	};
90 
91 	ssize_t l, left;
92 	char *p;
93 	const struct mafield *f;
94 
95 	strcpy(buffer, "dmi");
96 	p = buffer + 3; left = buffer_size - 4;
97 
98 	for (f = fields; f->prefix && left > 0; f++) {
99 		const char *c;
100 		char *t;
101 
102 		c = dmi_get_system_info(f->field);
103 		if (!c)
104 			continue;
105 
106 		t = kmalloc(strlen(c) + 1, GFP_KERNEL);
107 		if (!t)
108 			break;
109 		ascii_filter(t, c);
110 		l = scnprintf(p, left, ":%s%s", f->prefix, t);
111 		kfree(t);
112 
113 		p += l;
114 		left -= l;
115 	}
116 
117 	p[0] = ':';
118 	p[1] = 0;
119 
120 	return p - buffer + 1;
121 }
122 
123 static ssize_t sys_dmi_modalias_show(struct device *dev,
124 				     struct device_attribute *attr, char *page)
125 {
126 	ssize_t r;
127 	r = get_modalias(page, PAGE_SIZE-1);
128 	page[r] = '\n';
129 	page[r+1] = 0;
130 	return r+1;
131 }
132 
133 static struct device_attribute sys_dmi_modalias_attr =
134 	__ATTR(modalias, 0444, sys_dmi_modalias_show, NULL);
135 
136 static struct attribute *sys_dmi_attributes[DMI_STRING_MAX+2];
137 
138 static struct attribute_group sys_dmi_attribute_group = {
139 	.attrs = sys_dmi_attributes,
140 };
141 
142 static const struct attribute_group* sys_dmi_attribute_groups[] = {
143 	&sys_dmi_attribute_group,
144 	NULL
145 };
146 
147 static int dmi_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
148 {
149 	ssize_t len;
150 
151 	if (add_uevent_var(env, "MODALIAS="))
152 		return -ENOMEM;
153 	len = get_modalias(&env->buf[env->buflen - 1],
154 			   sizeof(env->buf) - env->buflen);
155 	if (len >= (sizeof(env->buf) - env->buflen))
156 		return -ENOMEM;
157 	env->buflen += len;
158 	return 0;
159 }
160 
161 static struct class dmi_class = {
162 	.name = "dmi",
163 	.dev_release = (void(*)(struct device *)) kfree,
164 	.dev_uevent = dmi_dev_uevent,
165 };
166 
167 static struct device *dmi_dev;
168 
169 /* Initialization */
170 
171 #define ADD_DMI_ATTR(_name, _field) \
172 	if (dmi_get_system_info(_field)) \
173 		sys_dmi_attributes[i++] = &sys_dmi_##_name##_attr.dev_attr.attr;
174 
175 /* In a separate function to keep gcc 3.2 happy - do NOT merge this in
176    dmi_id_init! */
177 static void __init dmi_id_init_attr_table(void)
178 {
179 	int i;
180 
181 	/* Not necessarily all DMI fields are available on all
182 	 * systems, hence let's built an attribute table of just
183 	 * what's available */
184 	i = 0;
185 	ADD_DMI_ATTR(bios_vendor,       DMI_BIOS_VENDOR);
186 	ADD_DMI_ATTR(bios_version,      DMI_BIOS_VERSION);
187 	ADD_DMI_ATTR(bios_date,         DMI_BIOS_DATE);
188 	ADD_DMI_ATTR(sys_vendor,        DMI_SYS_VENDOR);
189 	ADD_DMI_ATTR(product_name,      DMI_PRODUCT_NAME);
190 	ADD_DMI_ATTR(product_version,   DMI_PRODUCT_VERSION);
191 	ADD_DMI_ATTR(product_serial,    DMI_PRODUCT_SERIAL);
192 	ADD_DMI_ATTR(product_uuid,      DMI_PRODUCT_UUID);
193 	ADD_DMI_ATTR(board_vendor,      DMI_BOARD_VENDOR);
194 	ADD_DMI_ATTR(board_name,        DMI_BOARD_NAME);
195 	ADD_DMI_ATTR(board_version,     DMI_BOARD_VERSION);
196 	ADD_DMI_ATTR(board_serial,      DMI_BOARD_SERIAL);
197 	ADD_DMI_ATTR(board_asset_tag,   DMI_BOARD_ASSET_TAG);
198 	ADD_DMI_ATTR(chassis_vendor,    DMI_CHASSIS_VENDOR);
199 	ADD_DMI_ATTR(chassis_type,      DMI_CHASSIS_TYPE);
200 	ADD_DMI_ATTR(chassis_version,   DMI_CHASSIS_VERSION);
201 	ADD_DMI_ATTR(chassis_serial,    DMI_CHASSIS_SERIAL);
202 	ADD_DMI_ATTR(chassis_asset_tag, DMI_CHASSIS_ASSET_TAG);
203 	sys_dmi_attributes[i++] = &sys_dmi_modalias_attr.attr;
204 }
205 
206 static int __init dmi_id_init(void)
207 {
208 	int ret;
209 
210 	if (!dmi_available)
211 		return -ENODEV;
212 
213 	dmi_id_init_attr_table();
214 
215 	ret = class_register(&dmi_class);
216 	if (ret)
217 		return ret;
218 
219 	dmi_dev = kzalloc(sizeof(*dmi_dev), GFP_KERNEL);
220 	if (!dmi_dev) {
221 		ret = -ENOMEM;
222 		goto fail_class_unregister;
223 	}
224 
225 	dmi_dev->class = &dmi_class;
226 	dev_set_name(dmi_dev, "id");
227 	dmi_dev->groups = sys_dmi_attribute_groups;
228 
229 	ret = device_register(dmi_dev);
230 	if (ret)
231 		goto fail_class_unregister;
232 
233 	return 0;
234 
235 fail_class_unregister:
236 
237 	class_unregister(&dmi_class);
238 
239 	return ret;
240 }
241 
242 arch_initcall(dmi_id_init);
243