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1// SPDX-License-Identifier: GPL-2.02/*3 * Functions corresponding to enumeration type attributes under4 * BIOS Enumeration GUID for use with hp-bioscfg driver.5 *6 * Copyright (c) 2022 HP Development Company, L.P.7 */8 9#include "bioscfg.h"10 11GET_INSTANCE_ID(enumeration);12 13static ssize_t current_value_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)14{15 int instance_id = get_enumeration_instance_id(kobj);16 17 if (instance_id < 0)18 return -EIO;19 20 return sysfs_emit(buf, "%s\n",21 bioscfg_drv.enumeration_data[instance_id].current_value);22}23 24/**25 * validate_enumeration_input() -26 * Validate input of current_value against possible values27 *28 * @instance_id: The instance on which input is validated29 * @buf: Input value30 */31static int validate_enumeration_input(int instance_id, const char *buf)32{33 int i;34 int found = 0;35 struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id];36 37 /* Is it a read only attribute */38 if (enum_data->common.is_readonly)39 return -EIO;40 41 for (i = 0; i < enum_data->possible_values_size && !found; i++)42 if (!strcmp(enum_data->possible_values[i], buf))43 found = 1;44 45 if (!found)46 return -EINVAL;47 48 return 0;49}50 51static void update_enumeration_value(int instance_id, char *attr_value)52{53 struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id];54 55 strscpy(enum_data->current_value, attr_value);56}57 58ATTRIBUTE_S_COMMON_PROPERTY_SHOW(display_name, enumeration);59static struct kobj_attribute enumeration_display_name =60 __ATTR_RO(display_name);61 62ATTRIBUTE_PROPERTY_STORE(current_value, enumeration);63static struct kobj_attribute enumeration_current_val =64 __ATTR_RW(current_value);65 66ATTRIBUTE_VALUES_PROPERTY_SHOW(possible_values, enumeration, SEMICOLON_SEP);67static struct kobj_attribute enumeration_poss_val =68 __ATTR_RO(possible_values);69 70static ssize_t type_show(struct kobject *kobj, struct kobj_attribute *attr,71 char *buf)72{73 return sysfs_emit(buf, "enumeration\n");74}75 76static struct kobj_attribute enumeration_type =77 __ATTR_RO(type);78 79static struct attribute *enumeration_attrs[] = {80 &common_display_langcode.attr,81 &enumeration_display_name.attr,82 &enumeration_current_val.attr,83 &enumeration_poss_val.attr,84 &enumeration_type.attr,85 NULL86};87 88static const struct attribute_group enumeration_attr_group = {89 .attrs = enumeration_attrs,90};91 92int hp_alloc_enumeration_data(void)93{94 bioscfg_drv.enumeration_instances_count =95 hp_get_instance_count(HP_WMI_BIOS_ENUMERATION_GUID);96 97 bioscfg_drv.enumeration_data = kcalloc(bioscfg_drv.enumeration_instances_count,98 sizeof(*bioscfg_drv.enumeration_data), GFP_KERNEL);99 if (!bioscfg_drv.enumeration_data) {100 bioscfg_drv.enumeration_instances_count = 0;101 return -ENOMEM;102 }103 return 0;104}105 106/* Expected Values types associated with each element */107static const acpi_object_type expected_enum_types[] = {108 [NAME] = ACPI_TYPE_STRING,109 [VALUE] = ACPI_TYPE_STRING,110 [PATH] = ACPI_TYPE_STRING,111 [IS_READONLY] = ACPI_TYPE_INTEGER,112 [DISPLAY_IN_UI] = ACPI_TYPE_INTEGER,113 [REQUIRES_PHYSICAL_PRESENCE] = ACPI_TYPE_INTEGER,114 [SEQUENCE] = ACPI_TYPE_INTEGER,115 [PREREQUISITES_SIZE] = ACPI_TYPE_INTEGER,116 [PREREQUISITES] = ACPI_TYPE_STRING,117 [SECURITY_LEVEL] = ACPI_TYPE_INTEGER,118 [ENUM_CURRENT_VALUE] = ACPI_TYPE_STRING,119 [ENUM_SIZE] = ACPI_TYPE_INTEGER,120 [ENUM_POSSIBLE_VALUES] = ACPI_TYPE_STRING,121};122 123static int hp_populate_enumeration_elements_from_package(union acpi_object *enum_obj,124 int enum_obj_count,125 int instance_id)126{127 char *str_value = NULL;128 int value_len;129 u32 size = 0;130 u32 int_value = 0;131 int elem = 0;132 int reqs;133 int pos_values;134 int ret;135 int eloc;136 struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id];137 138 for (elem = 1, eloc = 1; elem < enum_obj_count; elem++, eloc++) {139 /* ONLY look at the first ENUM_ELEM_CNT elements */140 if (eloc == ENUM_ELEM_CNT)141 goto exit_enumeration_package;142 143 switch (enum_obj[elem].type) {144 case ACPI_TYPE_STRING:145 if (PREREQUISITES != elem && ENUM_POSSIBLE_VALUES != elem) {146 ret = hp_convert_hexstr_to_str(enum_obj[elem].string.pointer,147 enum_obj[elem].string.length,148 &str_value, &value_len);149 if (ret)150 return -EINVAL;151 }152 break;153 case ACPI_TYPE_INTEGER:154 int_value = (u32)enum_obj[elem].integer.value;155 break;156 default:157 pr_warn("Unsupported object type [%d]\n", enum_obj[elem].type);158 continue;159 }160 161 /* Check that both expected and read object type match */162 if (expected_enum_types[eloc] != enum_obj[elem].type) {163 pr_err("Error expected type %d for elem %d, but got type %d instead\n",164 expected_enum_types[eloc], elem, enum_obj[elem].type);165 kfree(str_value);166 return -EIO;167 }168 169 /* Assign appropriate element value to corresponding field */170 switch (eloc) {171 case NAME:172 case VALUE:173 break;174 case PATH:175 strscpy(enum_data->common.path, str_value);176 break;177 case IS_READONLY:178 enum_data->common.is_readonly = int_value;179 break;180 case DISPLAY_IN_UI:181 enum_data->common.display_in_ui = int_value;182 break;183 case REQUIRES_PHYSICAL_PRESENCE:184 enum_data->common.requires_physical_presence = int_value;185 break;186 case SEQUENCE:187 enum_data->common.sequence = int_value;188 break;189 case PREREQUISITES_SIZE:190 if (int_value > MAX_PREREQUISITES_SIZE) {191 pr_warn("Prerequisites size value exceeded the maximum number of elements supported or data may be malformed\n");192 int_value = MAX_PREREQUISITES_SIZE;193 }194 enum_data->common.prerequisites_size = int_value;195 196 /*197 * This step is needed to keep the expected198 * element list pointing to the right obj[elem].type199 * when the size is zero. PREREQUISITES200 * object is omitted by BIOS when the size is201 * zero.202 */203 if (int_value == 0)204 eloc++;205 break;206 207 case PREREQUISITES:208 size = min_t(u32, enum_data->common.prerequisites_size, MAX_PREREQUISITES_SIZE);209 for (reqs = 0; reqs < size; reqs++) {210 if (elem >= enum_obj_count) {211 pr_err("Error enum-objects package is too small\n");212 return -EINVAL;213 }214 215 ret = hp_convert_hexstr_to_str(enum_obj[elem + reqs].string.pointer,216 enum_obj[elem + reqs].string.length,217 &str_value, &value_len);218 219 if (ret)220 return -EINVAL;221 222 strscpy(enum_data->common.prerequisites[reqs], str_value);223 224 kfree(str_value);225 str_value = NULL;226 }227 break;228 229 case SECURITY_LEVEL:230 enum_data->common.security_level = int_value;231 break;232 233 case ENUM_CURRENT_VALUE:234 strscpy(enum_data->current_value, str_value);235 break;236 case ENUM_SIZE:237 if (int_value > MAX_VALUES_SIZE) {238 pr_warn("Possible number values size value exceeded the maximum number of elements supported or data may be malformed\n");239 int_value = MAX_VALUES_SIZE;240 }241 enum_data->possible_values_size = int_value;242 243 /*244 * This step is needed to keep the expected245 * element list pointing to the right obj[elem].type246 * when the size is zero. POSSIBLE_VALUES247 * object is omitted by BIOS when the size is zero.248 */249 if (int_value == 0)250 eloc++;251 break;252 253 case ENUM_POSSIBLE_VALUES:254 size = enum_data->possible_values_size;255 256 for (pos_values = 0; pos_values < size && pos_values < MAX_VALUES_SIZE;257 pos_values++) {258 if (elem >= enum_obj_count) {259 pr_err("Error enum-objects package is too small\n");260 return -EINVAL;261 }262 263 ret = hp_convert_hexstr_to_str(enum_obj[elem + pos_values].string.pointer,264 enum_obj[elem + pos_values].string.length,265 &str_value, &value_len);266 267 if (ret)268 return -EINVAL;269 270 /*271 * ignore strings when possible values size272 * is greater than MAX_VALUES_SIZE273 */274 if (size < MAX_VALUES_SIZE)275 strscpy(enum_data->possible_values[pos_values], str_value);276 277 kfree(str_value);278 str_value = NULL;279 }280 break;281 default:282 pr_warn("Invalid element: %d found in Enumeration attribute or data may be malformed\n", elem);283 break;284 }285 286 kfree(str_value);287 str_value = NULL;288 }289 290exit_enumeration_package:291 kfree(str_value);292 return 0;293}294 295/**296 * hp_populate_enumeration_package_data() -297 * Populate all properties of an instance under enumeration attribute298 *299 * @enum_obj: ACPI object with enumeration data300 * @instance_id: The instance to enumerate301 * @attr_name_kobj: The parent kernel object302 */303int hp_populate_enumeration_package_data(union acpi_object *enum_obj,304 int instance_id,305 struct kobject *attr_name_kobj)306{307 struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id];308 309 enum_data->attr_name_kobj = attr_name_kobj;310 311 hp_populate_enumeration_elements_from_package(enum_obj,312 enum_obj->package.count,313 instance_id);314 hp_update_attribute_permissions(enum_data->common.is_readonly,315 &enumeration_current_val);316 /*317 * Several attributes have names such "MONDAY". Friendly318 * user nane is generated to make the name more descriptive319 */320 hp_friendly_user_name_update(enum_data->common.path,321 attr_name_kobj->name,322 enum_data->common.display_name,323 sizeof(enum_data->common.display_name));324 return sysfs_create_group(attr_name_kobj, &enumeration_attr_group);325}326 327static int hp_populate_enumeration_elements_from_buffer(u8 *buffer_ptr, u32 *buffer_size,328 int instance_id)329{330 int values;331 struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id];332 int ret = 0;333 334 /*335 * Only data relevant to this driver and its functionality is336 * read. BIOS defines the order in which each * element is337 * read. Element 0 data is not relevant to this338 * driver hence it is ignored. For clarity, all element names339 * (DISPLAY_IN_UI) which defines the order in which is read340 * and the name matches the variable where the data is stored.341 *342 * In earlier implementation, reported errors were ignored343 * causing the data to remain uninitialized. It is not344 * possible to determine if data read from BIOS is valid or345 * not. It is for this reason functions may return a error346 * without validating the data itself.347 */348 349 // VALUE:350 ret = hp_get_string_from_buffer(&buffer_ptr, buffer_size, enum_data->current_value,351 sizeof(enum_data->current_value));352 if (ret < 0)353 goto buffer_exit;354 355 // COMMON:356 ret = hp_get_common_data_from_buffer(&buffer_ptr, buffer_size, &enum_data->common);357 if (ret < 0)358 goto buffer_exit;359 360 // ENUM_CURRENT_VALUE:361 ret = hp_get_string_from_buffer(&buffer_ptr, buffer_size,362 enum_data->current_value,363 sizeof(enum_data->current_value));364 if (ret < 0)365 goto buffer_exit;366 367 // ENUM_SIZE:368 ret = hp_get_integer_from_buffer(&buffer_ptr, buffer_size,369 &enum_data->possible_values_size);370 371 if (enum_data->possible_values_size > MAX_VALUES_SIZE) {372 /* Report a message and limit possible values size to maximum value */373 pr_warn("Enum Possible size value exceeded the maximum number of elements supported or data may be malformed\n");374 enum_data->possible_values_size = MAX_VALUES_SIZE;375 }376 377 // ENUM_POSSIBLE_VALUES:378 for (values = 0; values < enum_data->possible_values_size; values++) {379 ret = hp_get_string_from_buffer(&buffer_ptr, buffer_size,380 enum_data->possible_values[values],381 sizeof(enum_data->possible_values[values]));382 if (ret < 0)383 break;384 }385 386buffer_exit:387 return ret;388}389 390/**391 * hp_populate_enumeration_buffer_data() -392 * Populate all properties of an instance under enumeration attribute393 *394 * @buffer_ptr: Buffer pointer395 * @buffer_size: Buffer size396 * @instance_id: The instance to enumerate397 * @attr_name_kobj: The parent kernel object398 */399int hp_populate_enumeration_buffer_data(u8 *buffer_ptr, u32 *buffer_size,400 int instance_id,401 struct kobject *attr_name_kobj)402{403 struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id];404 int ret = 0;405 406 enum_data->attr_name_kobj = attr_name_kobj;407 408 /* Populate enumeration elements */409 ret = hp_populate_enumeration_elements_from_buffer(buffer_ptr, buffer_size,410 instance_id);411 if (ret < 0)412 return ret;413 414 hp_update_attribute_permissions(enum_data->common.is_readonly,415 &enumeration_current_val);416 /*417 * Several attributes have names such "MONDAY". A Friendlier418 * user nane is generated to make the name more descriptive419 */420 hp_friendly_user_name_update(enum_data->common.path,421 attr_name_kobj->name,422 enum_data->common.display_name,423 sizeof(enum_data->common.display_name));424 425 return sysfs_create_group(attr_name_kobj, &enumeration_attr_group);426}427 428/**429 * hp_exit_enumeration_attributes() - Clear all attribute data430 *431 * Clears all data allocated for this group of attributes432 */433void hp_exit_enumeration_attributes(void)434{435 int instance_id;436 437 for (instance_id = 0; instance_id < bioscfg_drv.enumeration_instances_count;438 instance_id++) {439 struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id];440 struct kobject *attr_name_kobj = enum_data->attr_name_kobj;441 442 if (attr_name_kobj)443 sysfs_remove_group(attr_name_kobj, &enumeration_attr_group);444 }445 bioscfg_drv.enumeration_instances_count = 0;446 447 kfree(bioscfg_drv.enumeration_data);448 bioscfg_drv.enumeration_data = NULL;449}450