1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Export SMBIOS/DMI info via sysfs to userspace 4 * 5 * Copyright 2007, Lennart Poettering 6 */ 7 8 #include <linux/module.h> 9 #include <linux/kernel.h> 10 #include <linux/init.h> 11 #include <linux/dmi.h> 12 #include <linux/device.h> 13 #include <linux/slab.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(bios_release, 0444, DMI_BIOS_RELEASE); 46 DEFINE_DMI_ATTR_WITH_SHOW(ec_firmware_release, 0444, DMI_EC_FIRMWARE_RELEASE); 47 DEFINE_DMI_ATTR_WITH_SHOW(product_name, 0444, DMI_PRODUCT_NAME); 48 DEFINE_DMI_ATTR_WITH_SHOW(product_version, 0444, DMI_PRODUCT_VERSION); 49 DEFINE_DMI_ATTR_WITH_SHOW(product_serial, 0400, DMI_PRODUCT_SERIAL); 50 DEFINE_DMI_ATTR_WITH_SHOW(product_uuid, 0400, DMI_PRODUCT_UUID); 51 DEFINE_DMI_ATTR_WITH_SHOW(product_sku, 0444, DMI_PRODUCT_SKU); 52 DEFINE_DMI_ATTR_WITH_SHOW(product_family, 0444, DMI_PRODUCT_FAMILY); 53 DEFINE_DMI_ATTR_WITH_SHOW(board_vendor, 0444, DMI_BOARD_VENDOR); 54 DEFINE_DMI_ATTR_WITH_SHOW(board_name, 0444, DMI_BOARD_NAME); 55 DEFINE_DMI_ATTR_WITH_SHOW(board_version, 0444, DMI_BOARD_VERSION); 56 DEFINE_DMI_ATTR_WITH_SHOW(board_serial, 0400, DMI_BOARD_SERIAL); 57 DEFINE_DMI_ATTR_WITH_SHOW(board_asset_tag, 0444, DMI_BOARD_ASSET_TAG); 58 DEFINE_DMI_ATTR_WITH_SHOW(chassis_vendor, 0444, DMI_CHASSIS_VENDOR); 59 DEFINE_DMI_ATTR_WITH_SHOW(chassis_type, 0444, DMI_CHASSIS_TYPE); 60 DEFINE_DMI_ATTR_WITH_SHOW(chassis_version, 0444, DMI_CHASSIS_VERSION); 61 DEFINE_DMI_ATTR_WITH_SHOW(chassis_serial, 0400, DMI_CHASSIS_SERIAL); 62 DEFINE_DMI_ATTR_WITH_SHOW(chassis_asset_tag, 0444, DMI_CHASSIS_ASSET_TAG); 63 64 static void ascii_filter(char *d, const char *s) 65 { 66 /* Filter out characters we don't want to see in the modalias string */ 67 for (; *s; s++) 68 if (*s > ' ' && *s < 127 && *s != ':') 69 *(d++) = *s; 70 71 *d = 0; 72 } 73 74 static ssize_t get_modalias(char *buffer, size_t buffer_size) 75 { 76 static const struct mafield { 77 const char *prefix; 78 int field; 79 } fields[] = { 80 { "bvn", DMI_BIOS_VENDOR }, 81 { "bvr", DMI_BIOS_VERSION }, 82 { "bd", DMI_BIOS_DATE }, 83 { "br", DMI_BIOS_RELEASE }, 84 { "efr", DMI_EC_FIRMWARE_RELEASE }, 85 { "svn", DMI_SYS_VENDOR }, 86 { "pn", DMI_PRODUCT_NAME }, 87 { "pvr", DMI_PRODUCT_VERSION }, 88 { "sku", DMI_PRODUCT_SKU }, 89 { "rvn", DMI_BOARD_VENDOR }, 90 { "rn", DMI_BOARD_NAME }, 91 { "rvr", DMI_BOARD_VERSION }, 92 { "cvn", DMI_CHASSIS_VENDOR }, 93 { "ct", DMI_CHASSIS_TYPE }, 94 { "cvr", DMI_CHASSIS_VERSION }, 95 { NULL, DMI_NONE } 96 }; 97 98 ssize_t l, left; 99 char *p; 100 const struct mafield *f; 101 102 strcpy(buffer, "dmi"); 103 p = buffer + 3; left = buffer_size - 4; 104 105 for (f = fields; f->prefix && left > 0; f++) { 106 const char *c; 107 char *t; 108 109 c = dmi_get_system_info(f->field); 110 if (!c) 111 continue; 112 113 t = kmalloc(strlen(c) + 1, GFP_KERNEL); 114 if (!t) 115 break; 116 ascii_filter(t, c); 117 l = scnprintf(p, left, ":%s%s", f->prefix, t); 118 kfree(t); 119 120 p += l; 121 left -= l; 122 } 123 124 p[0] = ':'; 125 p[1] = 0; 126 127 return p - buffer + 1; 128 } 129 130 static ssize_t sys_dmi_modalias_show(struct device *dev, 131 struct device_attribute *attr, char *page) 132 { 133 ssize_t r; 134 r = get_modalias(page, PAGE_SIZE-1); 135 page[r] = '\n'; 136 page[r+1] = 0; 137 return r+1; 138 } 139 140 static struct device_attribute sys_dmi_modalias_attr = 141 __ATTR(modalias, 0444, sys_dmi_modalias_show, NULL); 142 143 static struct attribute *sys_dmi_attributes[DMI_STRING_MAX+2]; 144 145 static struct attribute_group sys_dmi_attribute_group = { 146 .attrs = sys_dmi_attributes, 147 }; 148 149 static const struct attribute_group* sys_dmi_attribute_groups[] = { 150 &sys_dmi_attribute_group, 151 NULL 152 }; 153 154 static int dmi_dev_uevent(struct device *dev, struct kobj_uevent_env *env) 155 { 156 ssize_t len; 157 158 if (add_uevent_var(env, "MODALIAS=")) 159 return -ENOMEM; 160 len = get_modalias(&env->buf[env->buflen - 1], 161 sizeof(env->buf) - env->buflen); 162 if (len >= (sizeof(env->buf) - env->buflen)) 163 return -ENOMEM; 164 env->buflen += len; 165 return 0; 166 } 167 168 static struct class dmi_class = { 169 .name = "dmi", 170 .dev_release = (void(*)(struct device *)) kfree, 171 .dev_uevent = dmi_dev_uevent, 172 }; 173 174 static struct device *dmi_dev; 175 176 /* Initialization */ 177 178 #define ADD_DMI_ATTR(_name, _field) \ 179 if (dmi_get_system_info(_field)) \ 180 sys_dmi_attributes[i++] = &sys_dmi_##_name##_attr.dev_attr.attr; 181 182 /* In a separate function to keep gcc 3.2 happy - do NOT merge this in 183 dmi_id_init! */ 184 static void __init dmi_id_init_attr_table(void) 185 { 186 int i; 187 188 /* Not necessarily all DMI fields are available on all 189 * systems, hence let's built an attribute table of just 190 * what's available */ 191 i = 0; 192 ADD_DMI_ATTR(bios_vendor, DMI_BIOS_VENDOR); 193 ADD_DMI_ATTR(bios_version, DMI_BIOS_VERSION); 194 ADD_DMI_ATTR(bios_date, DMI_BIOS_DATE); 195 ADD_DMI_ATTR(bios_release, DMI_BIOS_RELEASE); 196 ADD_DMI_ATTR(ec_firmware_release, DMI_EC_FIRMWARE_RELEASE); 197 ADD_DMI_ATTR(sys_vendor, DMI_SYS_VENDOR); 198 ADD_DMI_ATTR(product_name, DMI_PRODUCT_NAME); 199 ADD_DMI_ATTR(product_version, DMI_PRODUCT_VERSION); 200 ADD_DMI_ATTR(product_serial, DMI_PRODUCT_SERIAL); 201 ADD_DMI_ATTR(product_uuid, DMI_PRODUCT_UUID); 202 ADD_DMI_ATTR(product_family, DMI_PRODUCT_FAMILY); 203 ADD_DMI_ATTR(product_sku, DMI_PRODUCT_SKU); 204 ADD_DMI_ATTR(board_vendor, DMI_BOARD_VENDOR); 205 ADD_DMI_ATTR(board_name, DMI_BOARD_NAME); 206 ADD_DMI_ATTR(board_version, DMI_BOARD_VERSION); 207 ADD_DMI_ATTR(board_serial, DMI_BOARD_SERIAL); 208 ADD_DMI_ATTR(board_asset_tag, DMI_BOARD_ASSET_TAG); 209 ADD_DMI_ATTR(chassis_vendor, DMI_CHASSIS_VENDOR); 210 ADD_DMI_ATTR(chassis_type, DMI_CHASSIS_TYPE); 211 ADD_DMI_ATTR(chassis_version, DMI_CHASSIS_VERSION); 212 ADD_DMI_ATTR(chassis_serial, DMI_CHASSIS_SERIAL); 213 ADD_DMI_ATTR(chassis_asset_tag, DMI_CHASSIS_ASSET_TAG); 214 sys_dmi_attributes[i++] = &sys_dmi_modalias_attr.attr; 215 } 216 217 static int __init dmi_id_init(void) 218 { 219 int ret; 220 221 if (!dmi_available) 222 return -ENODEV; 223 224 dmi_id_init_attr_table(); 225 226 ret = class_register(&dmi_class); 227 if (ret) 228 return ret; 229 230 dmi_dev = kzalloc(sizeof(*dmi_dev), GFP_KERNEL); 231 if (!dmi_dev) { 232 ret = -ENOMEM; 233 goto fail_class_unregister; 234 } 235 236 dmi_dev->class = &dmi_class; 237 dev_set_name(dmi_dev, "id"); 238 dmi_dev->groups = sys_dmi_attribute_groups; 239 240 ret = device_register(dmi_dev); 241 if (ret) 242 goto fail_put_dmi_dev; 243 244 return 0; 245 246 fail_put_dmi_dev: 247 put_device(dmi_dev); 248 249 fail_class_unregister: 250 class_unregister(&dmi_class); 251 252 return ret; 253 } 254 255 arch_initcall(dmi_id_init); 256