diff options
Diffstat (limited to 'drivers/platform/x86/hp/hp-bioscfg/enum-attributes.c')
| -rw-r--r-- | drivers/platform/x86/hp/hp-bioscfg/enum-attributes.c | 457 |
1 files changed, 457 insertions, 0 deletions
diff --git a/drivers/platform/x86/hp/hp-bioscfg/enum-attributes.c b/drivers/platform/x86/hp/hp-bioscfg/enum-attributes.c new file mode 100644 index 000000000000..a2402d31c146 --- /dev/null +++ b/drivers/platform/x86/hp/hp-bioscfg/enum-attributes.c @@ -0,0 +1,457 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Functions corresponding to enumeration type attributes under + * BIOS Enumeration GUID for use with hp-bioscfg driver. + * + * Copyright (c) 2022 HP Development Company, L.P. + */ + +#include "bioscfg.h" + +GET_INSTANCE_ID(enumeration); + +static ssize_t current_value_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) +{ + int instance_id = get_enumeration_instance_id(kobj); + + if (instance_id < 0) + return -EIO; + + return sysfs_emit(buf, "%s\n", + bioscfg_drv.enumeration_data[instance_id].current_value); +} + +/** + * validate_enumeration_input() - + * Validate input of current_value against possible values + * + * @instance_id: The instance on which input is validated + * @buf: Input value + */ +static int validate_enumeration_input(int instance_id, const char *buf) +{ + int i; + int found = 0; + struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id]; + + /* Is it a read only attribute */ + if (enum_data->common.is_readonly) + return -EIO; + + for (i = 0; i < enum_data->possible_values_size && !found; i++) + if (!strcmp(enum_data->possible_values[i], buf)) + found = 1; + + if (!found) + return -EINVAL; + + return 0; +} + +static void update_enumeration_value(int instance_id, char *attr_value) +{ + struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id]; + + strscpy(enum_data->current_value, + attr_value, + sizeof(enum_data->current_value)); +} + +ATTRIBUTE_S_COMMON_PROPERTY_SHOW(display_name, enumeration); +static struct kobj_attribute enumeration_display_name = + __ATTR_RO(display_name); + +ATTRIBUTE_PROPERTY_STORE(current_value, enumeration); +static struct kobj_attribute enumeration_current_val = + __ATTR_RW(current_value); + +ATTRIBUTE_VALUES_PROPERTY_SHOW(possible_values, enumeration, SEMICOLON_SEP); +static struct kobj_attribute enumeration_poss_val = + __ATTR_RO(possible_values); + +static ssize_t type_show(struct kobject *kobj, struct kobj_attribute *attr, + char *buf) +{ + return sysfs_emit(buf, "enumeration\n"); +} + +static struct kobj_attribute enumeration_type = + __ATTR_RO(type); + +static struct attribute *enumeration_attrs[] = { + &common_display_langcode.attr, + &enumeration_display_name.attr, + &enumeration_current_val.attr, + &enumeration_poss_val.attr, + &enumeration_type.attr, + NULL +}; + +static const struct attribute_group enumeration_attr_group = { + .attrs = enumeration_attrs, +}; + +int hp_alloc_enumeration_data(void) +{ + bioscfg_drv.enumeration_instances_count = + hp_get_instance_count(HP_WMI_BIOS_ENUMERATION_GUID); + + bioscfg_drv.enumeration_data = kcalloc(bioscfg_drv.enumeration_instances_count, + sizeof(*bioscfg_drv.enumeration_data), GFP_KERNEL); + if (!bioscfg_drv.enumeration_data) { + bioscfg_drv.enumeration_instances_count = 0; + return -ENOMEM; + } + return 0; +} + +/* Expected Values types associated with each element */ +static const acpi_object_type expected_enum_types[] = { + [NAME] = ACPI_TYPE_STRING, + [VALUE] = ACPI_TYPE_STRING, + [PATH] = ACPI_TYPE_STRING, + [IS_READONLY] = ACPI_TYPE_INTEGER, + [DISPLAY_IN_UI] = ACPI_TYPE_INTEGER, + [REQUIRES_PHYSICAL_PRESENCE] = ACPI_TYPE_INTEGER, + [SEQUENCE] = ACPI_TYPE_INTEGER, + [PREREQUISITES_SIZE] = ACPI_TYPE_INTEGER, + [PREREQUISITES] = ACPI_TYPE_STRING, + [SECURITY_LEVEL] = ACPI_TYPE_INTEGER, + [ENUM_CURRENT_VALUE] = ACPI_TYPE_STRING, + [ENUM_SIZE] = ACPI_TYPE_INTEGER, + [ENUM_POSSIBLE_VALUES] = ACPI_TYPE_STRING, +}; + +static int hp_populate_enumeration_elements_from_package(union acpi_object *enum_obj, + int enum_obj_count, + int instance_id) +{ + char *str_value = NULL; + int value_len; + u32 size = 0; + u32 int_value = 0; + int elem = 0; + int reqs; + int pos_values; + int ret; + int eloc; + struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id]; + + for (elem = 1, eloc = 1; elem < enum_obj_count; elem++, eloc++) { + /* ONLY look at the first ENUM_ELEM_CNT elements */ + if (eloc == ENUM_ELEM_CNT) + goto exit_enumeration_package; + + switch (enum_obj[elem].type) { + case ACPI_TYPE_STRING: + if (PREREQUISITES != elem && ENUM_POSSIBLE_VALUES != elem) { + ret = hp_convert_hexstr_to_str(enum_obj[elem].string.pointer, + enum_obj[elem].string.length, + &str_value, &value_len); + if (ret) + return -EINVAL; + } + break; + case ACPI_TYPE_INTEGER: + int_value = (u32)enum_obj[elem].integer.value; + break; + default: + pr_warn("Unsupported object type [%d]\n", enum_obj[elem].type); + continue; + } + + /* Check that both expected and read object type match */ + if (expected_enum_types[eloc] != enum_obj[elem].type) { + pr_err("Error expected type %d for elem %d, but got type %d instead\n", + expected_enum_types[eloc], elem, enum_obj[elem].type); + kfree(str_value); + return -EIO; + } + + /* Assign appropriate element value to corresponding field */ + switch (eloc) { + case NAME: + case VALUE: + break; + case PATH: + strscpy(enum_data->common.path, str_value, + sizeof(enum_data->common.path)); + break; + case IS_READONLY: + enum_data->common.is_readonly = int_value; + break; + case DISPLAY_IN_UI: + enum_data->common.display_in_ui = int_value; + break; + case REQUIRES_PHYSICAL_PRESENCE: + enum_data->common.requires_physical_presence = int_value; + break; + case SEQUENCE: + enum_data->common.sequence = int_value; + break; + case PREREQUISITES_SIZE: + if (int_value > MAX_PREREQUISITES_SIZE) { + pr_warn("Prerequisites size value exceeded the maximum number of elements supported or data may be malformed\n"); + int_value = MAX_PREREQUISITES_SIZE; + } + enum_data->common.prerequisites_size = int_value; + + /* + * This step is needed to keep the expected + * element list pointing to the right obj[elem].type + * when the size is zero. PREREQUISITES + * object is omitted by BIOS when the size is + * zero. + */ + if (int_value == 0) + eloc++; + break; + + case PREREQUISITES: + size = min_t(u32, enum_data->common.prerequisites_size, MAX_PREREQUISITES_SIZE); + for (reqs = 0; reqs < size; reqs++) { + if (elem >= enum_obj_count) { + pr_err("Error enum-objects package is too small\n"); + return -EINVAL; + } + + ret = hp_convert_hexstr_to_str(enum_obj[elem + reqs].string.pointer, + enum_obj[elem + reqs].string.length, + &str_value, &value_len); + + if (ret) + return -EINVAL; + + strscpy(enum_data->common.prerequisites[reqs], + str_value, + sizeof(enum_data->common.prerequisites[reqs])); + + kfree(str_value); + str_value = NULL; + } + break; + + case SECURITY_LEVEL: + enum_data->common.security_level = int_value; + break; + + case ENUM_CURRENT_VALUE: + strscpy(enum_data->current_value, + str_value, sizeof(enum_data->current_value)); + break; + case ENUM_SIZE: + if (int_value > MAX_VALUES_SIZE) { + pr_warn("Possible number values size value exceeded the maximum number of elements supported or data may be malformed\n"); + int_value = MAX_VALUES_SIZE; + } + enum_data->possible_values_size = int_value; + + /* + * This step is needed to keep the expected + * element list pointing to the right obj[elem].type + * when the size is zero. POSSIBLE_VALUES + * object is omitted by BIOS when the size is zero. + */ + if (int_value == 0) + eloc++; + break; + + case ENUM_POSSIBLE_VALUES: + size = enum_data->possible_values_size; + + for (pos_values = 0; pos_values < size && pos_values < MAX_VALUES_SIZE; + pos_values++) { + if (elem >= enum_obj_count) { + pr_err("Error enum-objects package is too small\n"); + return -EINVAL; + } + + ret = hp_convert_hexstr_to_str(enum_obj[elem + pos_values].string.pointer, + enum_obj[elem + pos_values].string.length, + &str_value, &value_len); + + if (ret) + return -EINVAL; + + /* + * ignore strings when possible values size + * is greater than MAX_VALUES_SIZE + */ + if (size < MAX_VALUES_SIZE) + strscpy(enum_data->possible_values[pos_values], + str_value, + sizeof(enum_data->possible_values[pos_values])); + + kfree(str_value); + str_value = NULL; + } + break; + default: + pr_warn("Invalid element: %d found in Enumeration attribute or data may be malformed\n", elem); + break; + } + + kfree(str_value); + str_value = NULL; + } + +exit_enumeration_package: + kfree(str_value); + return 0; +} + +/** + * hp_populate_enumeration_package_data() - + * Populate all properties of an instance under enumeration attribute + * + * @enum_obj: ACPI object with enumeration data + * @instance_id: The instance to enumerate + * @attr_name_kobj: The parent kernel object + */ +int hp_populate_enumeration_package_data(union acpi_object *enum_obj, + int instance_id, + struct kobject *attr_name_kobj) +{ + struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id]; + + enum_data->attr_name_kobj = attr_name_kobj; + + hp_populate_enumeration_elements_from_package(enum_obj, + enum_obj->package.count, + instance_id); + hp_update_attribute_permissions(enum_data->common.is_readonly, + &enumeration_current_val); + /* + * Several attributes have names such "MONDAY". Friendly + * user nane is generated to make the name more descriptive + */ + hp_friendly_user_name_update(enum_data->common.path, + attr_name_kobj->name, + enum_data->common.display_name, + sizeof(enum_data->common.display_name)); + return sysfs_create_group(attr_name_kobj, &enumeration_attr_group); +} + +static int hp_populate_enumeration_elements_from_buffer(u8 *buffer_ptr, u32 *buffer_size, + int instance_id) +{ + int values; + struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id]; + int ret = 0; + + /* + * Only data relevant to this driver and its functionality is + * read. BIOS defines the order in which each * element is + * read. Element 0 data is not relevant to this + * driver hence it is ignored. For clarity, all element names + * (DISPLAY_IN_UI) which defines the order in which is read + * and the name matches the variable where the data is stored. + * + * In earlier implementation, reported errors were ignored + * causing the data to remain uninitialized. It is not + * possible to determine if data read from BIOS is valid or + * not. It is for this reason functions may return a error + * without validating the data itself. + */ + + // VALUE: + ret = hp_get_string_from_buffer(&buffer_ptr, buffer_size, enum_data->current_value, + sizeof(enum_data->current_value)); + if (ret < 0) + goto buffer_exit; + + // COMMON: + ret = hp_get_common_data_from_buffer(&buffer_ptr, buffer_size, &enum_data->common); + if (ret < 0) + goto buffer_exit; + + // ENUM_CURRENT_VALUE: + ret = hp_get_string_from_buffer(&buffer_ptr, buffer_size, + enum_data->current_value, + sizeof(enum_data->current_value)); + if (ret < 0) + goto buffer_exit; + + // ENUM_SIZE: + ret = hp_get_integer_from_buffer(&buffer_ptr, buffer_size, + &enum_data->possible_values_size); + + if (enum_data->possible_values_size > MAX_VALUES_SIZE) { + /* Report a message and limit possible values size to maximum value */ + pr_warn("Enum Possible size value exceeded the maximum number of elements supported or data may be malformed\n"); + enum_data->possible_values_size = MAX_VALUES_SIZE; + } + + // ENUM_POSSIBLE_VALUES: + for (values = 0; values < enum_data->possible_values_size; values++) { + ret = hp_get_string_from_buffer(&buffer_ptr, buffer_size, + enum_data->possible_values[values], + sizeof(enum_data->possible_values[values])); + if (ret < 0) + break; + } + +buffer_exit: + return ret; +} + +/** + * hp_populate_enumeration_buffer_data() - + * Populate all properties of an instance under enumeration attribute + * + * @buffer_ptr: Buffer pointer + * @buffer_size: Buffer size + * @instance_id: The instance to enumerate + * @attr_name_kobj: The parent kernel object + */ +int hp_populate_enumeration_buffer_data(u8 *buffer_ptr, u32 *buffer_size, + int instance_id, + struct kobject *attr_name_kobj) +{ + struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id]; + int ret = 0; + + enum_data->attr_name_kobj = attr_name_kobj; + + /* Populate enumeration elements */ + ret = hp_populate_enumeration_elements_from_buffer(buffer_ptr, buffer_size, + instance_id); + if (ret < 0) + return ret; + + hp_update_attribute_permissions(enum_data->common.is_readonly, + &enumeration_current_val); + /* + * Several attributes have names such "MONDAY". A Friendlier + * user nane is generated to make the name more descriptive + */ + hp_friendly_user_name_update(enum_data->common.path, + attr_name_kobj->name, + enum_data->common.display_name, + sizeof(enum_data->common.display_name)); + + return sysfs_create_group(attr_name_kobj, &enumeration_attr_group); +} + +/** + * hp_exit_enumeration_attributes() - Clear all attribute data + * + * Clears all data allocated for this group of attributes + */ +void hp_exit_enumeration_attributes(void) +{ + int instance_id; + + for (instance_id = 0; instance_id < bioscfg_drv.enumeration_instances_count; + instance_id++) { + struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id]; + struct kobject *attr_name_kobj = enum_data->attr_name_kobj; + + if (attr_name_kobj) + sysfs_remove_group(attr_name_kobj, &enumeration_attr_group); + } + bioscfg_drv.enumeration_instances_count = 0; + + kfree(bioscfg_drv.enumeration_data); + bioscfg_drv.enumeration_data = NULL; +} |