From 6f2c06d5a467a372a92696685541aee3c9053685 Mon Sep 17 00:00:00 2001 From: Jorge Lopez Date: Thu, 8 Jun 2023 11:33:12 -0500 Subject: [PATCH] platform/x86: hp-bioscfg: int-attributes MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Add integer attributes support to hp-bioscfg. HP BIOS Configuration driver purpose is to provide a driver supporting the latest sysfs class firmware attributes framework allowing the user to change BIOS settings and security solutions on HP Inc.’s commercial notebooks. Signed-off-by: Jorge Lopez Reviewed-by: Thomas Weißschuh Link: https://lore.kernel.org/r/20230608163319.18934-7-jorge.lopez2@hp.com Signed-off-by: Hans de Goede --- .../platform/x86/hp/hp-bioscfg/int-attributes.c | 409 +++++++++++++++++++++ 1 file changed, 409 insertions(+) create mode 100644 drivers/platform/x86/hp/hp-bioscfg/int-attributes.c diff --git a/drivers/platform/x86/hp/hp-bioscfg/int-attributes.c b/drivers/platform/x86/hp/hp-bioscfg/int-attributes.c new file mode 100644 index 0000000..7364c5e --- /dev/null +++ b/drivers/platform/x86/hp/hp-bioscfg/int-attributes.c @@ -0,0 +1,409 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Functions corresponding to integer type attributes under + * BIOS Enumeration GUID for use with hp-bioscfg driver. + * + * Copyright (c) 2022 Hewlett-Packard Inc. + */ + +#include "bioscfg.h" + +GET_INSTANCE_ID(integer); + +static ssize_t current_value_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) +{ + int instance_id = get_integer_instance_id(kobj); + + if (instance_id < 0) + return -EIO; + + return sysfs_emit(buf, "%d\n", + bioscfg_drv.integer_data[instance_id].current_value); +} + +/** + * validate_integer_input() - + * Validate input of current_value against lower and upper bound + * + * @instance_id: The instance on which input is validated + * @buf: Input value + */ +static int validate_integer_input(int instance_id, char *buf) +{ + int in_val; + int ret; + struct integer_data *integer_data = &bioscfg_drv.integer_data[instance_id]; + + /* BIOS treats it as a read only attribute */ + if (integer_data->common.is_readonly) + return -EIO; + + ret = kstrtoint(buf, 10, &in_val); + if (ret < 0) + return ret; + + if (in_val < integer_data->lower_bound || + in_val > integer_data->upper_bound) + return -ERANGE; + + return 0; +} + +static void update_integer_value(int instance_id, char *attr_value) +{ + int in_val; + int ret; + struct integer_data *integer_data = &bioscfg_drv.integer_data[instance_id]; + + ret = kstrtoint(attr_value, 10, &in_val); + if (ret == 0) + integer_data->current_value = in_val; + else + pr_warn("Invalid integer value found: %s\n", attr_value); +} + +ATTRIBUTE_S_COMMON_PROPERTY_SHOW(display_name, integer); +static struct kobj_attribute integer_display_name = + __ATTR_RO(display_name); + +ATTRIBUTE_PROPERTY_STORE(current_value, integer); +static struct kobj_attribute integer_current_val = + __ATTR_RW_MODE(current_value, 0644); + +ATTRIBUTE_N_PROPERTY_SHOW(lower_bound, integer); +static struct kobj_attribute integer_lower_bound = + __ATTR_RO(lower_bound); + +ATTRIBUTE_N_PROPERTY_SHOW(upper_bound, integer); +static struct kobj_attribute integer_upper_bound = + __ATTR_RO(upper_bound); + +ATTRIBUTE_N_PROPERTY_SHOW(scalar_increment, integer); +static struct kobj_attribute integer_scalar_increment = + __ATTR_RO(scalar_increment); + +static ssize_t type_show(struct kobject *kobj, struct kobj_attribute *attr, + char *buf) +{ + return sysfs_emit(buf, "integer\n"); +} + +static struct kobj_attribute integer_type = + __ATTR_RO(type); + +static struct attribute *integer_attrs[] = { + &common_display_langcode.attr, + &integer_display_name.attr, + &integer_current_val.attr, + &integer_lower_bound.attr, + &integer_upper_bound.attr, + &integer_scalar_increment.attr, + &integer_type.attr, + NULL +}; + +static const struct attribute_group integer_attr_group = { + .attrs = integer_attrs, +}; + +int hp_alloc_integer_data(void) +{ + bioscfg_drv.integer_instances_count = hp_get_instance_count(HP_WMI_BIOS_INTEGER_GUID); + bioscfg_drv.integer_data = kcalloc(bioscfg_drv.integer_instances_count, + sizeof(*bioscfg_drv.integer_data), GFP_KERNEL); + + if (!bioscfg_drv.integer_data) { + bioscfg_drv.integer_instances_count = 0; + return -ENOMEM; + } + return 0; +} + +/* Expected Values types associated with each element */ +static const acpi_object_type expected_integer_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, + [INT_LOWER_BOUND] = ACPI_TYPE_INTEGER, + [INT_UPPER_BOUND] = ACPI_TYPE_INTEGER, + [INT_SCALAR_INCREMENT] = ACPI_TYPE_INTEGER, +}; + +static int hp_populate_integer_elements_from_package(union acpi_object *integer_obj, + int integer_obj_count, + int instance_id) +{ + char *str_value = NULL; + int value_len; + int ret; + u32 int_value; + int elem; + int reqs; + int eloc; + int size; + struct integer_data *integer_data = &bioscfg_drv.integer_data[instance_id]; + + if (!integer_obj) + return -EINVAL; + + for (elem = 1, eloc = 1; elem < integer_obj_count; elem++, eloc++) { + /* ONLY look at the first INTEGER_ELEM_CNT elements */ + if (eloc == INT_ELEM_CNT) + goto exit_integer_package; + + switch (integer_obj[elem].type) { + case ACPI_TYPE_STRING: + if (elem != PREREQUISITES) { + ret = hp_convert_hexstr_to_str(integer_obj[elem].string.pointer, + integer_obj[elem].string.length, + &str_value, &value_len); + if (ret) + continue; + } + break; + case ACPI_TYPE_INTEGER: + int_value = (u32)integer_obj[elem].integer.value; + break; + default: + pr_warn("Unsupported object type [%d]\n", integer_obj[elem].type); + continue; + } + /* Check that both expected and read object type match */ + if (expected_integer_types[eloc] != integer_obj[elem].type) { + pr_err("Error expected type %d for elem %d, but got type %d instead\n", + expected_integer_types[eloc], elem, integer_obj[elem].type); + return -EIO; + } + /* Assign appropriate element value to corresponding field*/ + switch (eloc) { + case VALUE: + ret = kstrtoint(str_value, 10, &int_value); + if (ret) + continue; + + integer_data->current_value = int_value; + break; + case PATH: + strscpy(integer_data->common.path, str_value, + sizeof(integer_data->common.path)); + break; + case IS_READONLY: + integer_data->common.is_readonly = int_value; + break; + case DISPLAY_IN_UI: + integer_data->common.display_in_ui = int_value; + break; + case REQUIRES_PHYSICAL_PRESENCE: + integer_data->common.requires_physical_presence = int_value; + break; + case SEQUENCE: + integer_data->common.sequence = int_value; + break; + case PREREQUISITES_SIZE: + if (integer_data->common.prerequisites_size > MAX_PREREQUISITES_SIZE) + pr_warn("Prerequisites size value exceeded the maximum number of elements supported or data may be malformed\n"); + /* + * This HACK 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 (integer_data->common.prerequisites_size == 0) + eloc++; + break; + case PREREQUISITES: + size = min_t(u32, integer_data->common.prerequisites_size, MAX_PREREQUISITES_SIZE); + + for (reqs = 0; reqs < size; reqs++) { + if (elem >= integer_obj_count) { + pr_err("Error elem-objects package is too small\n"); + return -EINVAL; + } + + ret = hp_convert_hexstr_to_str(integer_obj[elem + reqs].string.pointer, + integer_obj[elem + reqs].string.length, + &str_value, &value_len); + + if (ret) + continue; + + strscpy(integer_data->common.prerequisites[reqs], + str_value, + sizeof(integer_data->common.prerequisites[reqs])); + kfree(str_value); + } + break; + + case SECURITY_LEVEL: + integer_data->common.security_level = int_value; + break; + case INT_LOWER_BOUND: + integer_data->lower_bound = int_value; + break; + case INT_UPPER_BOUND: + integer_data->upper_bound = int_value; + break; + case INT_SCALAR_INCREMENT: + integer_data->scalar_increment = int_value; + break; + default: + pr_warn("Invalid element: %d found in Integer attribute or data may be malformed\n", elem); + break; + } + } +exit_integer_package: + kfree(str_value); + return 0; +} + +/** + * hp_populate_integer_package_data() - + * Populate all properties of an instance under integer attribute + * + * @integer_obj: ACPI object with integer data + * @instance_id: The instance to enumerate + * @attr_name_kobj: The parent kernel object + */ +int hp_populate_integer_package_data(union acpi_object *integer_obj, + int instance_id, + struct kobject *attr_name_kobj) +{ + struct integer_data *integer_data = &bioscfg_drv.integer_data[instance_id]; + + integer_data->attr_name_kobj = attr_name_kobj; + hp_populate_integer_elements_from_package(integer_obj, + integer_obj->package.count, + instance_id); + hp_update_attribute_permissions(integer_data->common.is_readonly, + &integer_current_val); + hp_friendly_user_name_update(integer_data->common.path, + attr_name_kobj->name, + integer_data->common.display_name, + sizeof(integer_data->common.display_name)); + return sysfs_create_group(attr_name_kobj, &integer_attr_group); +} + +static int hp_populate_integer_elements_from_buffer(u8 *buffer_ptr, u32 *buffer_size, + int instance_id) +{ + char *dst = NULL; + int dst_size = *buffer_size / sizeof(u16); + struct integer_data *integer_data = &bioscfg_drv.integer_data[instance_id]; + int ret = 0; + + dst = kcalloc(dst_size, sizeof(char), GFP_KERNEL); + if (!dst) + return -ENOMEM; + + /* + * 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: + integer_data->current_value = 0; + + hp_get_string_from_buffer(&buffer_ptr, buffer_size, dst, dst_size); + ret = kstrtoint(dst, 10, &integer_data->current_value); + if (ret) + pr_warn("Unable to convert string to integer: %s\n", dst); + kfree(dst); + + // COMMON: + ret = hp_get_common_data_from_buffer(&buffer_ptr, buffer_size, &integer_data->common); + if (ret < 0) + goto buffer_exit; + + // INT_LOWER_BOUND: + ret = hp_get_integer_from_buffer(&buffer_ptr, buffer_size, + &integer_data->lower_bound); + if (ret < 0) + goto buffer_exit; + + // INT_UPPER_BOUND: + ret = hp_get_integer_from_buffer(&buffer_ptr, buffer_size, + &integer_data->upper_bound); + if (ret < 0) + goto buffer_exit; + + // INT_SCALAR_INCREMENT: + ret = hp_get_integer_from_buffer(&buffer_ptr, buffer_size, + &integer_data->scalar_increment); + +buffer_exit: + return ret; +} + +/** + * hp_populate_integer_buffer_data() - + * Populate all properties of an instance under integer 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_integer_buffer_data(u8 *buffer_ptr, u32 *buffer_size, int instance_id, + struct kobject *attr_name_kobj) +{ + struct integer_data *integer_data = &bioscfg_drv.integer_data[instance_id]; + int ret = 0; + + integer_data->attr_name_kobj = attr_name_kobj; + + /* Populate integer elements */ + ret = hp_populate_integer_elements_from_buffer(buffer_ptr, buffer_size, + instance_id); + if (ret < 0) + return ret; + + hp_update_attribute_permissions(integer_data->common.is_readonly, + &integer_current_val); + hp_friendly_user_name_update(integer_data->common.path, + attr_name_kobj->name, + integer_data->common.display_name, + sizeof(integer_data->common.display_name)); + + return sysfs_create_group(attr_name_kobj, &integer_attr_group); +} + +/** + * hp_exit_integer_attributes() - Clear all attribute data + * + * Clears all data allocated for this group of attributes + */ +void hp_exit_integer_attributes(void) +{ + int instance_id; + + for (instance_id = 0; instance_id < bioscfg_drv.integer_instances_count; + instance_id++) { + struct kobject *attr_name_kobj = + bioscfg_drv.integer_data[instance_id].attr_name_kobj; + + if (attr_name_kobj) + sysfs_remove_group(attr_name_kobj, &integer_attr_group); + } + bioscfg_drv.integer_instances_count = 0; + + kfree(bioscfg_drv.integer_data); + bioscfg_drv.integer_data = NULL; +} -- 2.7.4