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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Export SMBIOS/DMI info via sysfs to userspace4 *5 * Copyright 2007, Lennart Poettering6 */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 /*77 * Note new fields need to be added at the end to keep compatibility78 * with udev's hwdb which does matches on "`cat dmi/id/modalias`*".79 */80 static const struct mafield {81 const char *prefix;82 int field;83 } fields[] = {84 { "bvn", DMI_BIOS_VENDOR },85 { "bvr", DMI_BIOS_VERSION },86 { "bd", DMI_BIOS_DATE },87 { "br", DMI_BIOS_RELEASE },88 { "efr", DMI_EC_FIRMWARE_RELEASE },89 { "svn", DMI_SYS_VENDOR },90 { "pn", DMI_PRODUCT_NAME },91 { "pvr", DMI_PRODUCT_VERSION },92 { "rvn", DMI_BOARD_VENDOR },93 { "rn", DMI_BOARD_NAME },94 { "rvr", DMI_BOARD_VERSION },95 { "cvn", DMI_CHASSIS_VENDOR },96 { "ct", DMI_CHASSIS_TYPE },97 { "cvr", DMI_CHASSIS_VERSION },98 { "sku", DMI_PRODUCT_SKU },99 { NULL, DMI_NONE }100 };101 102 ssize_t l, left;103 char *p;104 const struct mafield *f;105 106 strcpy(buffer, "dmi");107 p = buffer + 3; left = buffer_size - 4;108 109 for (f = fields; f->prefix && left > 0; f++) {110 const char *c;111 char *t;112 113 c = dmi_get_system_info(f->field);114 if (!c)115 continue;116 117 t = kmalloc(strlen(c) + 1, GFP_KERNEL);118 if (!t)119 break;120 ascii_filter(t, c);121 l = scnprintf(p, left, ":%s%s", f->prefix, t);122 kfree(t);123 124 p += l;125 left -= l;126 }127 128 p[0] = ':';129 p[1] = 0;130 131 return p - buffer + 1;132}133 134static ssize_t sys_dmi_modalias_show(struct device *dev,135 struct device_attribute *attr, char *page)136{137 ssize_t r;138 r = get_modalias(page, PAGE_SIZE-1);139 page[r] = '\n';140 page[r+1] = 0;141 return r+1;142}143 144static struct device_attribute sys_dmi_modalias_attr =145 __ATTR(modalias, 0444, sys_dmi_modalias_show, NULL);146 147static struct attribute *sys_dmi_attributes[DMI_STRING_MAX+2];148 149static struct attribute_group sys_dmi_attribute_group = {150 .attrs = sys_dmi_attributes,151};152 153static const struct attribute_group* sys_dmi_attribute_groups[] = {154 &sys_dmi_attribute_group,155 NULL156};157 158static int dmi_dev_uevent(const struct device *dev, struct kobj_uevent_env *env)159{160 ssize_t len;161 162 if (add_uevent_var(env, "MODALIAS="))163 return -ENOMEM;164 len = get_modalias(&env->buf[env->buflen - 1],165 sizeof(env->buf) - env->buflen);166 if (len >= (sizeof(env->buf) - env->buflen))167 return -ENOMEM;168 env->buflen += len;169 return 0;170}171 172static void dmi_dev_release(struct device *dev)173{174 kfree(dev);175}176 177static struct class dmi_class = {178 .name = "dmi",179 .dev_release = dmi_dev_release,180 .dev_uevent = dmi_dev_uevent,181};182 183static struct device *dmi_dev;184 185/* Initialization */186 187#define ADD_DMI_ATTR(_name, _field) \188 if (dmi_get_system_info(_field)) \189 sys_dmi_attributes[i++] = &sys_dmi_##_name##_attr.dev_attr.attr;190 191/* In a separate function to keep gcc 3.2 happy - do NOT merge this in192 dmi_id_init! */193static void __init dmi_id_init_attr_table(void)194{195 int i;196 197 /* Not necessarily all DMI fields are available on all198 * systems, hence let's built an attribute table of just199 * what's available */200 i = 0;201 ADD_DMI_ATTR(bios_vendor, DMI_BIOS_VENDOR);202 ADD_DMI_ATTR(bios_version, DMI_BIOS_VERSION);203 ADD_DMI_ATTR(bios_date, DMI_BIOS_DATE);204 ADD_DMI_ATTR(bios_release, DMI_BIOS_RELEASE);205 ADD_DMI_ATTR(ec_firmware_release, DMI_EC_FIRMWARE_RELEASE);206 ADD_DMI_ATTR(sys_vendor, DMI_SYS_VENDOR);207 ADD_DMI_ATTR(product_name, DMI_PRODUCT_NAME);208 ADD_DMI_ATTR(product_version, DMI_PRODUCT_VERSION);209 ADD_DMI_ATTR(product_serial, DMI_PRODUCT_SERIAL);210 ADD_DMI_ATTR(product_uuid, DMI_PRODUCT_UUID);211 ADD_DMI_ATTR(product_family, DMI_PRODUCT_FAMILY);212 ADD_DMI_ATTR(product_sku, DMI_PRODUCT_SKU);213 ADD_DMI_ATTR(board_vendor, DMI_BOARD_VENDOR);214 ADD_DMI_ATTR(board_name, DMI_BOARD_NAME);215 ADD_DMI_ATTR(board_version, DMI_BOARD_VERSION);216 ADD_DMI_ATTR(board_serial, DMI_BOARD_SERIAL);217 ADD_DMI_ATTR(board_asset_tag, DMI_BOARD_ASSET_TAG);218 ADD_DMI_ATTR(chassis_vendor, DMI_CHASSIS_VENDOR);219 ADD_DMI_ATTR(chassis_type, DMI_CHASSIS_TYPE);220 ADD_DMI_ATTR(chassis_version, DMI_CHASSIS_VERSION);221 ADD_DMI_ATTR(chassis_serial, DMI_CHASSIS_SERIAL);222 ADD_DMI_ATTR(chassis_asset_tag, DMI_CHASSIS_ASSET_TAG);223 sys_dmi_attributes[i++] = &sys_dmi_modalias_attr.attr;224}225 226static int __init dmi_id_init(void)227{228 int ret;229 230 if (!dmi_available)231 return -ENODEV;232 233 dmi_id_init_attr_table();234 235 ret = class_register(&dmi_class);236 if (ret)237 return ret;238 239 dmi_dev = kzalloc(sizeof(*dmi_dev), GFP_KERNEL);240 if (!dmi_dev) {241 ret = -ENOMEM;242 goto fail_class_unregister;243 }244 245 dmi_dev->class = &dmi_class;246 dev_set_name(dmi_dev, "id");247 dmi_dev->groups = sys_dmi_attribute_groups;248 249 ret = device_register(dmi_dev);250 if (ret)251 goto fail_put_dmi_dev;252 253 return 0;254 255fail_put_dmi_dev:256 put_device(dmi_dev);257 258fail_class_unregister:259 class_unregister(&dmi_class);260 261 return ret;262}263 264arch_initcall(dmi_id_init);265