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1// SPDX-License-Identifier: GPL-2.02/*3 * Functions corresponding to integer type attributes under4 * BIOS Enumeration GUID for use with hp-bioscfg driver.5 *6 * Copyright (c) 2022 Hewlett-Packard Inc.7 */8 9#include "bioscfg.h"10 11GET_INSTANCE_ID(integer);12 13static ssize_t current_value_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)14{15 int instance_id = get_integer_instance_id(kobj);16 17 if (instance_id < 0)18 return -EIO;19 20 return sysfs_emit(buf, "%d\n",21 bioscfg_drv.integer_data[instance_id].current_value);22}23 24/**25 * validate_integer_input() -26 * Validate input of current_value against lower and upper bound27 *28 * @instance_id: The instance on which input is validated29 * @buf: Input value30 */31static int validate_integer_input(int instance_id, char *buf)32{33 int in_val;34 int ret;35 struct integer_data *integer_data = &bioscfg_drv.integer_data[instance_id];36 37 /* BIOS treats it as a read only attribute */38 if (integer_data->common.is_readonly)39 return -EIO;40 41 ret = kstrtoint(buf, 10, &in_val);42 if (ret < 0)43 return ret;44 45 if (in_val < integer_data->lower_bound ||46 in_val > integer_data->upper_bound)47 return -ERANGE;48 49 return 0;50}51 52static void update_integer_value(int instance_id, char *attr_value)53{54 int in_val;55 int ret;56 struct integer_data *integer_data = &bioscfg_drv.integer_data[instance_id];57 58 ret = kstrtoint(attr_value, 10, &in_val);59 if (ret == 0)60 integer_data->current_value = in_val;61 else62 pr_warn("Invalid integer value found: %s\n", attr_value);63}64 65ATTRIBUTE_S_COMMON_PROPERTY_SHOW(display_name, integer);66static struct kobj_attribute integer_display_name =67 __ATTR_RO(display_name);68 69ATTRIBUTE_PROPERTY_STORE(current_value, integer);70static struct kobj_attribute integer_current_val =71 __ATTR_RW_MODE(current_value, 0644);72 73ATTRIBUTE_N_PROPERTY_SHOW(lower_bound, integer);74static struct kobj_attribute integer_lower_bound =75 __ATTR_RO(lower_bound);76 77ATTRIBUTE_N_PROPERTY_SHOW(upper_bound, integer);78static struct kobj_attribute integer_upper_bound =79 __ATTR_RO(upper_bound);80 81ATTRIBUTE_N_PROPERTY_SHOW(scalar_increment, integer);82static struct kobj_attribute integer_scalar_increment =83 __ATTR_RO(scalar_increment);84 85static ssize_t type_show(struct kobject *kobj, struct kobj_attribute *attr,86 char *buf)87{88 return sysfs_emit(buf, "integer\n");89}90 91static struct kobj_attribute integer_type =92 __ATTR_RO(type);93 94static struct attribute *integer_attrs[] = {95 &common_display_langcode.attr,96 &integer_display_name.attr,97 &integer_current_val.attr,98 &integer_lower_bound.attr,99 &integer_upper_bound.attr,100 &integer_scalar_increment.attr,101 &integer_type.attr,102 NULL103};104 105static const struct attribute_group integer_attr_group = {106 .attrs = integer_attrs,107};108 109int hp_alloc_integer_data(void)110{111 bioscfg_drv.integer_instances_count = hp_get_instance_count(HP_WMI_BIOS_INTEGER_GUID);112 bioscfg_drv.integer_data = kcalloc(bioscfg_drv.integer_instances_count,113 sizeof(*bioscfg_drv.integer_data), GFP_KERNEL);114 115 if (!bioscfg_drv.integer_data) {116 bioscfg_drv.integer_instances_count = 0;117 return -ENOMEM;118 }119 return 0;120}121 122/* Expected Values types associated with each element */123static const acpi_object_type expected_integer_types[] = {124 [NAME] = ACPI_TYPE_STRING,125 [VALUE] = ACPI_TYPE_STRING,126 [PATH] = ACPI_TYPE_STRING,127 [IS_READONLY] = ACPI_TYPE_INTEGER,128 [DISPLAY_IN_UI] = ACPI_TYPE_INTEGER,129 [REQUIRES_PHYSICAL_PRESENCE] = ACPI_TYPE_INTEGER,130 [SEQUENCE] = ACPI_TYPE_INTEGER,131 [PREREQUISITES_SIZE] = ACPI_TYPE_INTEGER,132 [PREREQUISITES] = ACPI_TYPE_STRING,133 [SECURITY_LEVEL] = ACPI_TYPE_INTEGER,134 [INT_LOWER_BOUND] = ACPI_TYPE_INTEGER,135 [INT_UPPER_BOUND] = ACPI_TYPE_INTEGER,136 [INT_SCALAR_INCREMENT] = ACPI_TYPE_INTEGER,137};138 139static int hp_populate_integer_elements_from_package(union acpi_object *integer_obj,140 int integer_obj_count,141 int instance_id)142{143 char *str_value = NULL;144 int value_len;145 int ret;146 u32 int_value = 0;147 int elem;148 int reqs;149 int eloc;150 int size;151 struct integer_data *integer_data = &bioscfg_drv.integer_data[instance_id];152 153 if (!integer_obj)154 return -EINVAL;155 156 for (elem = 1, eloc = 1; elem < integer_obj_count; elem++, eloc++) {157 /* ONLY look at the first INTEGER_ELEM_CNT elements */158 if (eloc == INT_ELEM_CNT)159 goto exit_integer_package;160 161 switch (integer_obj[elem].type) {162 case ACPI_TYPE_STRING:163 if (elem != PREREQUISITES) {164 ret = hp_convert_hexstr_to_str(integer_obj[elem].string.pointer,165 integer_obj[elem].string.length,166 &str_value, &value_len);167 if (ret)168 continue;169 }170 break;171 case ACPI_TYPE_INTEGER:172 int_value = (u32)integer_obj[elem].integer.value;173 break;174 default:175 pr_warn("Unsupported object type [%d]\n", integer_obj[elem].type);176 continue;177 }178 /* Check that both expected and read object type match */179 if (expected_integer_types[eloc] != integer_obj[elem].type) {180 pr_err("Error expected type %d for elem %d, but got type %d instead\n",181 expected_integer_types[eloc], elem, integer_obj[elem].type);182 kfree(str_value);183 return -EIO;184 }185 /* Assign appropriate element value to corresponding field*/186 switch (eloc) {187 case VALUE:188 ret = kstrtoint(str_value, 10, &int_value);189 if (ret)190 continue;191 192 integer_data->current_value = int_value;193 break;194 case PATH:195 strscpy(integer_data->common.path, str_value);196 break;197 case IS_READONLY:198 integer_data->common.is_readonly = int_value;199 break;200 case DISPLAY_IN_UI:201 integer_data->common.display_in_ui = int_value;202 break;203 case REQUIRES_PHYSICAL_PRESENCE:204 integer_data->common.requires_physical_presence = int_value;205 break;206 case SEQUENCE:207 integer_data->common.sequence = int_value;208 break;209 case PREREQUISITES_SIZE:210 if (int_value > MAX_PREREQUISITES_SIZE) {211 pr_warn("Prerequisites size value exceeded the maximum number of elements supported or data may be malformed\n");212 int_value = MAX_PREREQUISITES_SIZE;213 }214 integer_data->common.prerequisites_size = int_value;215 216 /*217 * This step is needed to keep the expected218 * element list pointing to the right obj[elem].type219 * when the size is zero. PREREQUISITES220 * object is omitted by BIOS when the size is221 * zero.222 */223 if (integer_data->common.prerequisites_size == 0)224 eloc++;225 break;226 case PREREQUISITES:227 size = min_t(u32, integer_data->common.prerequisites_size, MAX_PREREQUISITES_SIZE);228 229 for (reqs = 0; reqs < size; reqs++) {230 if (elem >= integer_obj_count) {231 pr_err("Error elem-objects package is too small\n");232 return -EINVAL;233 }234 235 ret = hp_convert_hexstr_to_str(integer_obj[elem + reqs].string.pointer,236 integer_obj[elem + reqs].string.length,237 &str_value, &value_len);238 239 if (ret)240 continue;241 242 strscpy(integer_data->common.prerequisites[reqs], str_value);243 kfree(str_value);244 str_value = NULL;245 }246 break;247 248 case SECURITY_LEVEL:249 integer_data->common.security_level = int_value;250 break;251 case INT_LOWER_BOUND:252 integer_data->lower_bound = int_value;253 break;254 case INT_UPPER_BOUND:255 integer_data->upper_bound = int_value;256 break;257 case INT_SCALAR_INCREMENT:258 integer_data->scalar_increment = int_value;259 break;260 default:261 pr_warn("Invalid element: %d found in Integer attribute or data may be malformed\n", elem);262 break;263 }264 265 kfree(str_value);266 str_value = NULL;267 }268exit_integer_package:269 kfree(str_value);270 return 0;271}272 273/**274 * hp_populate_integer_package_data() -275 * Populate all properties of an instance under integer attribute276 *277 * @integer_obj: ACPI object with integer data278 * @instance_id: The instance to enumerate279 * @attr_name_kobj: The parent kernel object280 */281int hp_populate_integer_package_data(union acpi_object *integer_obj,282 int instance_id,283 struct kobject *attr_name_kobj)284{285 struct integer_data *integer_data = &bioscfg_drv.integer_data[instance_id];286 287 integer_data->attr_name_kobj = attr_name_kobj;288 hp_populate_integer_elements_from_package(integer_obj,289 integer_obj->package.count,290 instance_id);291 hp_update_attribute_permissions(integer_data->common.is_readonly,292 &integer_current_val);293 hp_friendly_user_name_update(integer_data->common.path,294 attr_name_kobj->name,295 integer_data->common.display_name,296 sizeof(integer_data->common.display_name));297 return sysfs_create_group(attr_name_kobj, &integer_attr_group);298}299 300static int hp_populate_integer_elements_from_buffer(u8 *buffer_ptr, u32 *buffer_size,301 int instance_id)302{303 char *dst = NULL;304 int dst_size = *buffer_size / sizeof(u16);305 struct integer_data *integer_data = &bioscfg_drv.integer_data[instance_id];306 int ret = 0;307 308 dst = kcalloc(dst_size, sizeof(char), GFP_KERNEL);309 if (!dst)310 return -ENOMEM;311 312 /*313 * Only data relevant to this driver and its functionality is314 * read. BIOS defines the order in which each * element is315 * read. Element 0 data is not relevant to this316 * driver hence it is ignored. For clarity, all element names317 * (DISPLAY_IN_UI) which defines the order in which is read318 * and the name matches the variable where the data is stored.319 *320 * In earlier implementation, reported errors were ignored321 * causing the data to remain uninitialized. It is not322 * possible to determine if data read from BIOS is valid or323 * not. It is for this reason functions may return a error324 * without validating the data itself.325 */326 327 // VALUE:328 integer_data->current_value = 0;329 330 hp_get_string_from_buffer(&buffer_ptr, buffer_size, dst, dst_size);331 ret = kstrtoint(dst, 10, &integer_data->current_value);332 if (ret)333 pr_warn("Unable to convert string to integer: %s\n", dst);334 kfree(dst);335 336 // COMMON:337 ret = hp_get_common_data_from_buffer(&buffer_ptr, buffer_size, &integer_data->common);338 if (ret < 0)339 goto buffer_exit;340 341 // INT_LOWER_BOUND:342 ret = hp_get_integer_from_buffer(&buffer_ptr, buffer_size,343 &integer_data->lower_bound);344 if (ret < 0)345 goto buffer_exit;346 347 // INT_UPPER_BOUND:348 ret = hp_get_integer_from_buffer(&buffer_ptr, buffer_size,349 &integer_data->upper_bound);350 if (ret < 0)351 goto buffer_exit;352 353 // INT_SCALAR_INCREMENT:354 ret = hp_get_integer_from_buffer(&buffer_ptr, buffer_size,355 &integer_data->scalar_increment);356 357buffer_exit:358 return ret;359}360 361/**362 * hp_populate_integer_buffer_data() -363 * Populate all properties of an instance under integer attribute364 *365 * @buffer_ptr: Buffer pointer366 * @buffer_size: Buffer size367 * @instance_id: The instance to enumerate368 * @attr_name_kobj: The parent kernel object369 */370int hp_populate_integer_buffer_data(u8 *buffer_ptr, u32 *buffer_size, int instance_id,371 struct kobject *attr_name_kobj)372{373 struct integer_data *integer_data = &bioscfg_drv.integer_data[instance_id];374 int ret = 0;375 376 integer_data->attr_name_kobj = attr_name_kobj;377 378 /* Populate integer elements */379 ret = hp_populate_integer_elements_from_buffer(buffer_ptr, buffer_size,380 instance_id);381 if (ret < 0)382 return ret;383 384 hp_update_attribute_permissions(integer_data->common.is_readonly,385 &integer_current_val);386 hp_friendly_user_name_update(integer_data->common.path,387 attr_name_kobj->name,388 integer_data->common.display_name,389 sizeof(integer_data->common.display_name));390 391 return sysfs_create_group(attr_name_kobj, &integer_attr_group);392}393 394/**395 * hp_exit_integer_attributes() - Clear all attribute data396 *397 * Clears all data allocated for this group of attributes398 */399void hp_exit_integer_attributes(void)400{401 int instance_id;402 403 for (instance_id = 0; instance_id < bioscfg_drv.integer_instances_count;404 instance_id++) {405 struct kobject *attr_name_kobj =406 bioscfg_drv.integer_data[instance_id].attr_name_kobj;407 408 if (attr_name_kobj)409 sysfs_remove_group(attr_name_kobj, &integer_attr_group);410 }411 bioscfg_drv.integer_instances_count = 0;412 413 kfree(bioscfg_drv.integer_data);414 bioscfg_drv.integer_data = NULL;415}416