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 15struct 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 22static 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) \ 38static struct dmi_device_attribute sys_dmi_##_name##_attr = \ 39 DMI_ATTR(_name, _mode, sys_dmi_field_show, _field); 40 41DEFINE_DMI_ATTR_WITH_SHOW(bios_vendor, 0444, DMI_BIOS_VENDOR); 42DEFINE_DMI_ATTR_WITH_SHOW(bios_version, 0444, DMI_BIOS_VERSION); 43DEFINE_DMI_ATTR_WITH_SHOW(bios_date, 0444, DMI_BIOS_DATE); 44DEFINE_DMI_ATTR_WITH_SHOW(sys_vendor, 0444, DMI_SYS_VENDOR); 45DEFINE_DMI_ATTR_WITH_SHOW(bios_release, 0444, DMI_BIOS_RELEASE); 46DEFINE_DMI_ATTR_WITH_SHOW(ec_firmware_release, 0444, DMI_EC_FIRMWARE_RELEASE); 47DEFINE_DMI_ATTR_WITH_SHOW(product_name, 0444, DMI_PRODUCT_NAME); 48DEFINE_DMI_ATTR_WITH_SHOW(product_version, 0444, DMI_PRODUCT_VERSION); 49DEFINE_DMI_ATTR_WITH_SHOW(product_serial, 0400, DMI_PRODUCT_SERIAL); 50DEFINE_DMI_ATTR_WITH_SHOW(product_uuid, 0400, DMI_PRODUCT_UUID); 51DEFINE_DMI_ATTR_WITH_SHOW(product_sku, 0444, DMI_PRODUCT_SKU); 52DEFINE_DMI_ATTR_WITH_SHOW(product_family, 0444, DMI_PRODUCT_FAMILY); 53DEFINE_DMI_ATTR_WITH_SHOW(board_vendor, 0444, DMI_BOARD_VENDOR); 54DEFINE_DMI_ATTR_WITH_SHOW(board_name, 0444, DMI_BOARD_NAME); 55DEFINE_DMI_ATTR_WITH_SHOW(board_version, 0444, DMI_BOARD_VERSION); 56DEFINE_DMI_ATTR_WITH_SHOW(board_serial, 0400, DMI_BOARD_SERIAL); 57DEFINE_DMI_ATTR_WITH_SHOW(board_asset_tag, 0444, DMI_BOARD_ASSET_TAG); 58DEFINE_DMI_ATTR_WITH_SHOW(chassis_vendor, 0444, DMI_CHASSIS_VENDOR); 59DEFINE_DMI_ATTR_WITH_SHOW(chassis_type, 0444, DMI_CHASSIS_TYPE); 60DEFINE_DMI_ATTR_WITH_SHOW(chassis_version, 0444, DMI_CHASSIS_VERSION); 61DEFINE_DMI_ATTR_WITH_SHOW(chassis_serial, 0400, DMI_CHASSIS_SERIAL); 62DEFINE_DMI_ATTR_WITH_SHOW(chassis_asset_tag, 0444, DMI_CHASSIS_ASSET_TAG); 63 64static 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 74static 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 { "rvn", DMI_BOARD_VENDOR }, 89 { "rn", DMI_BOARD_NAME }, 90 { "rvr", DMI_BOARD_VERSION }, 91 { "cvn", DMI_CHASSIS_VENDOR }, 92 { "ct", DMI_CHASSIS_TYPE }, 93 { "cvr", DMI_CHASSIS_VERSION }, 94 { NULL, DMI_NONE } 95 }; 96 97 ssize_t l, left; 98 char *p; 99 const struct mafield *f; 100 101 strcpy(buffer, "dmi"); 102 p = buffer + 3; left = buffer_size - 4; 103 104 for (f = fields; f->prefix && left > 0; f++) { 105 const char *c; 106 char *t; 107 108 c = dmi_get_system_info(f->field); 109 if (!c) 110 continue; 111 112 t = kmalloc(strlen(c) + 1, GFP_KERNEL); 113 if (!t) 114 break; 115 ascii_filter(t, c); 116 l = scnprintf(p, left, ":%s%s", f->prefix, t); 117 kfree(t); 118 119 p += l; 120 left -= l; 121 } 122 123 p[0] = ':'; 124 p[1] = 0; 125 126 return p - buffer + 1; 127} 128 129static ssize_t sys_dmi_modalias_show(struct device *dev, 130 struct device_attribute *attr, char *page) 131{ 132 ssize_t r; 133 r = get_modalias(page, PAGE_SIZE-1); 134 page[r] = '\n'; 135 page[r+1] = 0; 136 return r+1; 137} 138 139static struct device_attribute sys_dmi_modalias_attr = 140 __ATTR(modalias, 0444, sys_dmi_modalias_show, NULL); 141 142static struct attribute *sys_dmi_attributes[DMI_STRING_MAX+2]; 143 144static struct attribute_group sys_dmi_attribute_group = { 145 .attrs = sys_dmi_attributes, 146}; 147 148static const struct attribute_group* sys_dmi_attribute_groups[] = { 149 &sys_dmi_attribute_group, 150 NULL 151}; 152 153static int dmi_dev_uevent(struct device *dev, struct kobj_uevent_env *env) 154{ 155 ssize_t len; 156 157 if (add_uevent_var(env, "MODALIAS=")) 158 return -ENOMEM; 159 len = get_modalias(&env->buf[env->buflen - 1], 160 sizeof(env->buf) - env->buflen); 161 if (len >= (sizeof(env->buf) - env->buflen)) 162 return -ENOMEM; 163 env->buflen += len; 164 return 0; 165} 166 167static struct class dmi_class = { 168 .name = "dmi", 169 .dev_release = (void(*)(struct device *)) kfree, 170 .dev_uevent = dmi_dev_uevent, 171}; 172 173static struct device *dmi_dev; 174 175/* Initialization */ 176 177#define ADD_DMI_ATTR(_name, _field) \ 178 if (dmi_get_system_info(_field)) \ 179 sys_dmi_attributes[i++] = &sys_dmi_##_name##_attr.dev_attr.attr; 180 181/* In a separate function to keep gcc 3.2 happy - do NOT merge this in 182 dmi_id_init! */ 183static void __init dmi_id_init_attr_table(void) 184{ 185 int i; 186 187 /* Not necessarily all DMI fields are available on all 188 * systems, hence let's built an attribute table of just 189 * what's available */ 190 i = 0; 191 ADD_DMI_ATTR(bios_vendor, DMI_BIOS_VENDOR); 192 ADD_DMI_ATTR(bios_version, DMI_BIOS_VERSION); 193 ADD_DMI_ATTR(bios_date, DMI_BIOS_DATE); 194 ADD_DMI_ATTR(bios_release, DMI_BIOS_RELEASE); 195 ADD_DMI_ATTR(ec_firmware_release, DMI_EC_FIRMWARE_RELEASE); 196 ADD_DMI_ATTR(sys_vendor, DMI_SYS_VENDOR); 197 ADD_DMI_ATTR(product_name, DMI_PRODUCT_NAME); 198 ADD_DMI_ATTR(product_version, DMI_PRODUCT_VERSION); 199 ADD_DMI_ATTR(product_serial, DMI_PRODUCT_SERIAL); 200 ADD_DMI_ATTR(product_uuid, DMI_PRODUCT_UUID); 201 ADD_DMI_ATTR(product_family, DMI_PRODUCT_FAMILY); 202 ADD_DMI_ATTR(product_sku, DMI_PRODUCT_SKU); 203 ADD_DMI_ATTR(board_vendor, DMI_BOARD_VENDOR); 204 ADD_DMI_ATTR(board_name, DMI_BOARD_NAME); 205 ADD_DMI_ATTR(board_version, DMI_BOARD_VERSION); 206 ADD_DMI_ATTR(board_serial, DMI_BOARD_SERIAL); 207 ADD_DMI_ATTR(board_asset_tag, DMI_BOARD_ASSET_TAG); 208 ADD_DMI_ATTR(chassis_vendor, DMI_CHASSIS_VENDOR); 209 ADD_DMI_ATTR(chassis_type, DMI_CHASSIS_TYPE); 210 ADD_DMI_ATTR(chassis_version, DMI_CHASSIS_VERSION); 211 ADD_DMI_ATTR(chassis_serial, DMI_CHASSIS_SERIAL); 212 ADD_DMI_ATTR(chassis_asset_tag, DMI_CHASSIS_ASSET_TAG); 213 sys_dmi_attributes[i++] = &sys_dmi_modalias_attr.attr; 214} 215 216static int __init dmi_id_init(void) 217{ 218 int ret; 219 220 if (!dmi_available) 221 return -ENODEV; 222 223 dmi_id_init_attr_table(); 224 225 ret = class_register(&dmi_class); 226 if (ret) 227 return ret; 228 229 dmi_dev = kzalloc(sizeof(*dmi_dev), GFP_KERNEL); 230 if (!dmi_dev) { 231 ret = -ENOMEM; 232 goto fail_class_unregister; 233 } 234 235 dmi_dev->class = &dmi_class; 236 dev_set_name(dmi_dev, "id"); 237 dmi_dev->groups = sys_dmi_attribute_groups; 238 239 ret = device_register(dmi_dev); 240 if (ret) 241 goto fail_put_dmi_dev; 242 243 return 0; 244 245fail_put_dmi_dev: 246 put_device(dmi_dev); 247 248fail_class_unregister: 249 class_unregister(&dmi_class); 250 251 return ret; 252} 253 254arch_initcall(dmi_id_init); 255