[v4,3/3] platform/x86: think-lmi: Add WMI interface support on Lenovo platforms

Message ID	20210526201447.3686-3-markpearson@lenovo.com (mailing list archive)
State	Accepted, archived
Headers	show Return-Path: <platform-driver-x86-owner@kernel.org> From: Mark Pearson <markpearson@lenovo.com> To: <markpearson@lenovo.com> CC: <hdegoede@redhat.com>, <andy.shevchenko@gmail.com>, <prasanth.ksr@dell.com>, <divya.bharathi@dell.com>, <Dell.Client.Kernel@dell.com>, <platform-driver-x86@vger.kernel.org> Subject: [PATCH v4 3/3] platform/x86: think-lmi: Add WMI interface support on Lenovo platforms Date: Wed, 26 May 2021 16:14:47 -0400 Message-ID: <20210526201447.3686-3-markpearson@lenovo.com> In-Reply-To: <20210526201447.3686-1-markpearson@lenovo.com> References: <markpearson@lenovo.com> <20210526201447.3686-1-markpearson@lenovo.com> MIME-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8bit Precedence: bulk
Series	[v4,1/3] platform/x86: firmware_attributes_class: Create helper file for handling firmware-attributes class registration events \| expand [v4,1/3] platform/x86: firmware_attributes_class: Create helper file for handling firmware-attribut… [v4,2/3] platform/x86: dell-wmi-sysman: Use firmware_attributes_class helper [v4,3/3] platform/x86: think-lmi: Add WMI interface support on Lenovo platforms

diff --git a/Documentation/ABI/testing/sysfs-class-firmware-attributes b/Documentation/ABI/testing/sysfs-class-firmware-attributes index 8ea59fea4..3348bf80a 100644 --- a/Documentation/ABI/testing/sysfs-class-firmware-attributes +++ b/Documentation/ABI/testing/sysfs-class-firmware-attributes @@ -197,8 +197,24 @@ Description: Drivers may emit a CHANGE uevent when a password is set or unset userspace may check it again. - On Dell systems, if Admin password is set, then all BIOS attributes + On Dell and Lenovo systems, if Admin password is set, then all BIOS attributes require password validation. + On Lenovo systems if you change the Admin password the new password is not active until + the next boot. + + Lenovo specific class extensions + ------------------------------ + + On Lenovo systems the following additional settings are available: + + lenovo_encoding: + The encoding method that is used. This can be either "ascii" + or "scancode". Default is set to "ascii" + + lenovo_kbdlang: + The keyboard language method that is used. This is generally a + two char code (e.g. "us", "fr", "gr") and may vary per platform. + Default is set to "us" What: /sys/class/firmware-attributes/*/attributes/pending_reboot Date: February 2021 diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig index 57da8352d..c61aab19e 100644 --- a/drivers/platform/x86/Kconfig +++ b/drivers/platform/x86/Kconfig @@ -639,6 +639,17 @@ config THINKPAD_ACPI_HOTKEY_POLL If you are not sure, say Y here. The driver enables polling only if it is strictly necessary to do so. +config THINKPAD_LMI + tristate "Lenovo WMI-based systems management driver" + depends on ACPI_WMI + select FW_ATTR_CLASS + help + This driver allows changing BIOS settings on Lenovo machines whose + BIOS support the WMI interface. + + To compile this driver as a module, choose M here: the module will + be called think-lmi. + config INTEL_ATOMISP2_LED tristate "Intel AtomISP2 camera LED driver" depends on GPIOLIB && LEDS_GPIO diff --git a/drivers/platform/x86/Makefile b/drivers/platform/x86/Makefile index 147573f69..cab19672e 100644 --- a/drivers/platform/x86/Makefile +++ b/drivers/platform/x86/Makefile @@ -64,6 +64,7 @@ obj-$(CONFIG_IBM_RTL) += ibm_rtl.o obj-$(CONFIG_IDEAPAD_LAPTOP) += ideapad-laptop.o obj-$(CONFIG_SENSORS_HDAPS) += hdaps.o obj-$(CONFIG_THINKPAD_ACPI) += thinkpad_acpi.o +obj-$(CONFIG_THINKPAD_LMI) += think-lmi.o # Intel obj-$(CONFIG_INTEL_ATOMISP2_LED) += intel_atomisp2_led.o diff --git a/drivers/platform/x86/think-lmi.c b/drivers/platform/x86/think-lmi.c new file mode 100644 index 000000000..3ccae8224 --- /dev/null +++ b/drivers/platform/x86/think-lmi.c @@ -0,0 +1,884 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * think-lmi.c - Think LMI BIOS configuration driver + * + * Copyright(C) 2019-2021 Lenovo + * + * Original code from Thinkpad-wmi project https://github.com/iksaif/thinkpad-wmi + * Copyright(C) 2017 Corentin Chary <corentin.chary@gmail.com> + * Distributed under the GPL-2.0 license + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/acpi.h> +#include <linux/fs.h> +#include <linux/wmi.h> +#include "firmware_attributes_class.h" +#include "think-lmi.h" + +/* + * Name: + * Lenovo_BiosSetting + * Description: + * Get item name and settings for current LMI instance. + * Type: + * Query + * Returns: + * "Item,Value" + * Example: + * "WakeOnLAN,Enable" + */ +#define LENOVO_BIOS_SETTING_GUID "51F5230E-9677-46CD-A1CF-C0B23EE34DB7" + +/* + * Name: + * Lenovo_SetBiosSetting + * Description: + * Change the BIOS setting to the desired value using the Lenovo_SetBiosSetting + * class. To save the settings, use the Lenovo_SaveBiosSetting class. + * BIOS settings and values are case sensitive. + * After making changes to the BIOS settings, you must reboot the computer + * before the changes will take effect. + * Type: + * Method + * Arguments: + * "Item,Value,Password,Encoding,KbdLang;" + * Example: + * "WakeOnLAN,Disable,pswd,ascii,us;" + */ +#define LENOVO_SET_BIOS_SETTINGS_GUID "98479A64-33F5-4E33-A707-8E251EBBC3A1" + +/* + * Name: + * Lenovo_SaveBiosSettings + * Description: + * Save any pending changes in settings. + * Type: + * Method + * Arguments: + * "Password,Encoding,KbdLang;" + * Example: + * "pswd,ascii,us;" + */ +#define LENOVO_SAVE_BIOS_SETTINGS_GUID "6A4B54EF-A5ED-4D33-9455-B0D9B48DF4B3" + +/* + * Name: + * Lenovo_BiosPasswordSettings + * Description: + * Return BIOS Password settings + * Type: + * Query + * Returns: + * PasswordMode, PasswordState, MinLength, MaxLength, + * SupportedEncoding, SupportedKeyboard + */ +#define LENOVO_BIOS_PASSWORD_SETTINGS_GUID "8ADB159E-1E32-455C-BC93-308A7ED98246" + +/* + * Name: + * Lenovo_SetBiosPassword + * Description: + * Change a specific password. + * - BIOS settings cannot be changed at the same boot as power-on + * passwords (POP) and hard disk passwords (HDP). If you want to change + * BIOS settings and POP or HDP, you must reboot the system after changing + * one of them. + * - A password cannot be set using this method when one does not already + * exist. Passwords can only be updated or cleared. + * Type: + * Method + * Arguments: + * "PasswordType,CurrentPassword,NewPassword,Encoding,KbdLang;" + * Example: + * "pop,oldpop,newpop,ascii,us;” + */ +#define LENOVO_SET_BIOS_PASSWORD_GUID "2651D9FD-911C-4B69-B94E-D0DED5963BD7" + +/* + * Name: + * Lenovo_GetBiosSelections + * Description: + * Return a list of valid settings for a given item. + * Type: + * Method + * Arguments: + * "Item" + * Returns: + * "Value1,Value2,Value3,..." + * Example: + * -> "FlashOverLAN" + * <- "Enabled,Disabled" + */ +#define LENOVO_GET_BIOS_SELECTIONS_GUID "7364651A-132F-4FE7-ADAA-40C6C7EE2E3B" + +#define TLMI_POP_PWD (1 << 0) +#define TLMI_PAP_PWD (1 << 1) + +static const struct tlmi_err_codes tlmi_errs[] = { + {"Success", 0}, + {"Not Supported", -EOPNOTSUPP}, + {"Invalid Parameter", -EINVAL}, + {"Access Denied", -EACCES}, + {"System Busy", -EBUSY}, +}; + +static const char * const encoding_options[] = { + [TLMI_ENCODING_ASCII] = "ascii", + [TLMI_ENCODING_SCANCODE] = "scancode", +}; +static struct think_lmi tlmi_priv; +struct class *fw_attr_class; + +/* ------ Utility functions ------------*/ +/* Convert BIOS WMI error string to suitable error code */ +static int tlmi_errstr_to_err(const char *errstr) +{ + int i; + + for (i = 0; i < sizeof(tlmi_errs)/sizeof(struct tlmi_err_codes); i++) { + if (!strcmp(tlmi_errs[i].err_str, errstr)) + return tlmi_errs[i].err_code; + } + return -EPERM; +} + +/* Extract error string from WMI return buffer */ +static int tlmi_extract_error(const struct acpi_buffer *output) +{ + const union acpi_object *obj; + + obj = output->pointer; + if (!obj) + return -ENOMEM; + if (obj->type != ACPI_TYPE_STRING || !obj->string.pointer) { + kfree(obj); + return -EIO; + } + return tlmi_errstr_to_err(obj->string.pointer); +} + +/* Utility function to execute WMI call to BIOS */ +static int tlmi_simple_call(const char *guid, const char *arg) +{ + const struct acpi_buffer input = { strlen(arg), (char *)arg }; + struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL }; + acpi_status status; + int i, err; + + /* + * Duplicated call required to match bios workaround for behavior + * seen when WMI accessed via scripting on other OS. + */ + for (i = 0; i < 2; i++) { + /* (re)initialize output buffer to default state */ + output.length = ACPI_ALLOCATE_BUFFER; + output.pointer = NULL; + + status = wmi_evaluate_method(guid, 0, 0, &input, &output); + if (ACPI_FAILURE(status)) { + kfree(output.pointer); + return -EIO; + } + err = tlmi_extract_error(&output); + kfree(output.pointer); + if (err) + return err; + } + return 0; +} + +/* Extract output string from WMI return buffer */ +static int tlmi_extract_output_string(const struct acpi_buffer *output, + char **string) +{ + const union acpi_object *obj; + char *s; + + obj = output->pointer; + if (!obj) + return -ENOMEM; + if (obj->type != ACPI_TYPE_STRING || !obj->string.pointer) { + kfree(obj); + return -EIO; + } + + s = kstrdup(obj->string.pointer, GFP_KERNEL); + if (!s) + return -ENOMEM; + *string = s; + return 0; +} + +/* ------ Core interface functions ------------*/ + +/* Get password settings from BIOS */ +static int tlmi_get_pwd_settings(struct tlmi_pwdcfg *pwdcfg) +{ + struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL }; + const union acpi_object *obj; + acpi_status status; + + if (!tlmi_priv.can_get_password_settings) + return -EOPNOTSUPP; + + status = wmi_query_block(LENOVO_BIOS_PASSWORD_SETTINGS_GUID, 0, + &output); + if (ACPI_FAILURE(status)) + return -EIO; + + obj = output.pointer; + if (!obj) + return -ENOMEM; + if (obj->type != ACPI_TYPE_BUFFER || !obj->buffer.pointer) { + kfree(obj); + return -EIO; + } + /* + * The size of thinkpad_wmi_pcfg on ThinkStation is larger than ThinkPad. + * To make the driver compatible on different brands, we permit it to get + * the data in below case. + */ + if (obj->buffer.length < sizeof(struct tlmi_pwdcfg)) { + pr_warn("Unknown pwdcfg buffer length %d\n", obj->buffer.length); + kfree(obj); + return -EIO; + } + memcpy(pwdcfg, obj->buffer.pointer, sizeof(struct tlmi_pwdcfg)); + kfree(obj); + return 0; +} + +static int tlmi_save_bios_settings(const char *password) +{ + return tlmi_simple_call(LENOVO_SAVE_BIOS_SETTINGS_GUID, + password); +} + +static int tlmi_setting(int item, char **value, const char *guid_string) +{ + struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL }; + acpi_status status; + int ret; + + status = wmi_query_block(guid_string, item, &output); + if (ACPI_FAILURE(status)) { + kfree(output.pointer); + return -EIO; + } + + ret = tlmi_extract_output_string(&output, value); + kfree(output.pointer); + return ret; +} + +static int tlmi_get_bios_selections(const char *item, char **value) +{ + const struct acpi_buffer input = { strlen(item), (char *)item }; + struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL }; + acpi_status status; + int ret; + + status = wmi_evaluate_method(LENOVO_GET_BIOS_SELECTIONS_GUID, + 0, 0, &input, &output); + + if (ACPI_FAILURE(status)) { + kfree(output.pointer); + return -EIO; + } + + ret = tlmi_extract_output_string(&output, value); + kfree(output.pointer); + return ret; +} + +/* ---- Authentication sysfs --------------------------------------------------------- */ +static ssize_t is_enabled_show(struct kobject *kobj, struct kobj_attribute *attr, + char *buf) +{ + struct tlmi_pwd_setting *setting = container_of(kobj, struct tlmi_pwd_setting, kobj); + + return sysfs_emit(buf, "%d\n", setting->valid); +} + +static struct kobj_attribute auth_is_pass_set = __ATTR_RO(is_enabled); + +static ssize_t current_password_store(struct kobject *kobj, + struct kobj_attribute *attr, + const char *buf, size_t count) +{ + struct tlmi_pwd_setting *setting = container_of(kobj, struct tlmi_pwd_setting, kobj); + int pwdlen; + + pwdlen = strlen(buf); + if (buf[pwdlen-1] == '\n') + pwdlen--; + + /* pwdlen == 0 is allowed to clear the password */ + if (pwdlen != 0 && ((pwdlen < setting->minlen) || (pwdlen > setting->maxlen))) + return -EINVAL; + + memcpy(setting->password, buf, pwdlen); + setting->password[pwdlen] = '\0'; + return count; +} + +static struct kobj_attribute auth_current_password = __ATTR_WO(current_password); + +static ssize_t new_password_store(struct kobject *kobj, + struct kobj_attribute *attr, + const char *buf, size_t count) +{ + struct tlmi_pwd_setting *setting = container_of(kobj, struct tlmi_pwd_setting, kobj); + int ret, pwdlen; + char *new_pwd; + char *auth_str; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + if (!tlmi_priv.can_set_bios_password) + return -EOPNOTSUPP; + + new_pwd = kstrdup(buf, GFP_KERNEL); + if (!new_pwd) + return -ENOMEM; + + /* Strip out CR if one is present, setting password won't work if it is present */ + strreplace(new_pwd, '\n', '\0'); + + pwdlen = strlen(new_pwd); + /* pwdlen == 0 is allowed to clear the password */ + if (pwdlen != 0 && ((pwdlen < setting->minlen) || (pwdlen > setting->maxlen))) { + ret = -EINVAL; + goto out; + } + + /* Format: 'PasswordType,CurrentPw,NewPw,Encoding,KbdLang;' */ + auth_str = kasprintf(GFP_KERNEL, "%s,%s,%s,%s,%s;", + setting->pwd_type, setting->password, new_pwd, + encoding_options[setting->encoding], setting->kbdlang); + if (!auth_str) { + ret = -ENOMEM; + goto out; + } + ret = tlmi_simple_call(LENOVO_SET_BIOS_PASSWORD_GUID, auth_str); + kfree(auth_str); +out: + kfree(new_pwd); + return ret ?: count; +} + +static struct kobj_attribute auth_new_password = __ATTR_WO(new_password); + +static ssize_t min_password_length_show(struct kobject *kobj, struct kobj_attribute *attr, + char *buf) +{ + struct tlmi_pwd_setting *setting = container_of(kobj, struct tlmi_pwd_setting, kobj); + + return sysfs_emit(buf, "%d\n", setting->minlen); +} + +static struct kobj_attribute auth_min_pass_length = __ATTR_RO(min_password_length); + +static ssize_t max_password_length_show(struct kobject *kobj, struct kobj_attribute *attr, + char *buf) +{ + struct tlmi_pwd_setting *setting = container_of(kobj, struct tlmi_pwd_setting, kobj); + + return sysfs_emit(buf, "%d\n", setting->maxlen); +} +static struct kobj_attribute auth_max_pass_length = __ATTR_RO(max_password_length); + +static ssize_t mechanism_show(struct kobject *kobj, struct kobj_attribute *attr, + char *buf) +{ + return sysfs_emit(buf, "password\n"); +} +static struct kobj_attribute auth_mechanism = __ATTR_RO(mechanism); + +static ssize_t encoding_show(struct kobject *kobj, struct kobj_attribute *attr, + char *buf) +{ + struct tlmi_pwd_setting *setting = container_of(kobj, struct tlmi_pwd_setting, kobj); + + return sysfs_emit(buf, "%s\n", encoding_options[setting->encoding]); +} + +static ssize_t encoding_store(struct kobject *kobj, + struct kobj_attribute *attr, + const char *buf, size_t count) +{ + struct tlmi_pwd_setting *setting = container_of(kobj, struct tlmi_pwd_setting, kobj); + int i; + + /* Scan for a matching profile */ + i = sysfs_match_string(encoding_options, buf); + if (i < 0) + return -EINVAL; + + setting->encoding = i; + return count; +} + +static struct kobj_attribute auth_encoding = __ATTR_RW(encoding); + +static ssize_t kbdlang_show(struct kobject *kobj, struct kobj_attribute *attr, + char *buf) +{ + struct tlmi_pwd_setting *setting = container_of(kobj, struct tlmi_pwd_setting, kobj); + + return sysfs_emit(buf, "%s\n", setting->kbdlang); +} + +static ssize_t kbdlang_store(struct kobject *kobj, + struct kobj_attribute *attr, + const char *buf, size_t count) +{ + struct tlmi_pwd_setting *setting = container_of(kobj, struct tlmi_pwd_setting, kobj); + int length; + + length = strlen(buf); + if (buf[length-1] == '\n') + length--; + + if (!length || (length >= TLMI_LANG_MAXLEN)) + return -EINVAL; + + memcpy(setting->kbdlang, buf, length); + setting->kbdlang[length] = '\0'; + return count; +} + +static struct kobj_attribute auth_kbdlang = __ATTR_RW(kbdlang); + +static ssize_t role_show(struct kobject *kobj, struct kobj_attribute *attr, + char *buf) +{ + struct tlmi_pwd_setting *setting = container_of(kobj, struct tlmi_pwd_setting, kobj); + + return sysfs_emit(buf, "%s\n", setting->role); +} +static struct kobj_attribute auth_role = __ATTR_RO(role); + +static struct attribute *auth_attrs[] = { + &auth_is_pass_set.attr, + &auth_min_pass_length.attr, + &auth_max_pass_length.attr, + &auth_current_password.attr, + &auth_new_password.attr, + &auth_role.attr, + &auth_mechanism.attr, + &auth_encoding.attr, + &auth_kbdlang.attr, + NULL +}; + +static const struct attribute_group auth_attr_group = { + .attrs = auth_attrs, +}; + +/* ---- Attributes sysfs --------------------------------------------------------- */ +static ssize_t display_name_show(struct kobject *kobj, struct kobj_attribute *attr, + char *buf) +{ + struct tlmi_attr_setting *setting = container_of(kobj, struct tlmi_attr_setting, kobj); + + return sysfs_emit(buf, "%s\n", setting->display_name); +} + +static ssize_t current_value_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) +{ + struct tlmi_attr_setting *setting = container_of(kobj, struct tlmi_attr_setting, kobj); + char *item; + int ret; + + ret = tlmi_setting(setting->index, &item, LENOVO_BIOS_SETTING_GUID); + if (ret) + return ret; + + ret = sysfs_emit(buf, "%s\n", item); + kfree(item); + return ret; +} + +static ssize_t possible_values_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) +{ + struct tlmi_attr_setting *setting = container_of(kobj, struct tlmi_attr_setting, kobj); + + if (!tlmi_priv.can_get_bios_selections) + return -EOPNOTSUPP; + + return sysfs_emit(buf, "%s\n", setting->possible_values); +} + +static ssize_t current_value_store(struct kobject *kobj, + struct kobj_attribute *attr, + const char *buf, size_t count) +{ + struct tlmi_attr_setting *setting = container_of(kobj, struct tlmi_attr_setting, kobj); + char *set_str = NULL, *new_setting = NULL; + char *auth_str = NULL; + int ret; + + if (!tlmi_priv.can_set_bios_settings) + return -EOPNOTSUPP; + + new_setting = kstrdup(buf, GFP_KERNEL); + if (!new_setting) + return -ENOMEM; + + /* Strip out CR if one is present */ + strreplace(new_setting, '\n', '\0'); + + if (tlmi_priv.pwd_admin->valid && tlmi_priv.pwd_admin->password) { + auth_str = kasprintf(GFP_KERNEL, "%s,%s,%s;", + tlmi_priv.pwd_admin->password, + encoding_options[tlmi_priv.pwd_admin->encoding], + tlmi_priv.pwd_admin->kbdlang); + if (!auth_str) { + ret = -ENOMEM; + goto out; + } + } + + if (auth_str) + set_str = kasprintf(GFP_KERNEL, "%s,%s,%s", setting->display_name, + new_setting, auth_str); + else + set_str = kasprintf(GFP_KERNEL, "%s,%s;", setting->display_name, + new_setting); + if (!set_str) { + ret = -ENOMEM; + goto out; + } + + ret = tlmi_simple_call(LENOVO_SET_BIOS_SETTINGS_GUID, set_str); + if (ret) + goto out; + + if (tlmi_priv.pwd_admin->valid && tlmi_priv.pwd_admin->password) + ret = tlmi_save_bios_settings(auth_str); + else + ret = tlmi_save_bios_settings(""); + +out: + kfree(auth_str); + kfree(set_str); + kfree(new_setting); + return ret ?: count; +} + +static struct kobj_attribute attr_displ_name = __ATTR_RO(display_name); + +static struct kobj_attribute attr_possible_values = __ATTR_RO(possible_values); + +static struct kobj_attribute attr_current_val = __ATTR_RW_MODE(current_value, 0600); + +static struct attribute *tlmi_attrs[] = { + &attr_displ_name.attr, + &attr_current_val.attr, + &attr_possible_values.attr, + NULL +}; + +static const struct attribute_group tlmi_attr_group = { + .attrs = tlmi_attrs, +}; + +static ssize_t tlmi_attr_show(struct kobject *kobj, struct attribute *attr, + char *buf) +{ + struct kobj_attribute *kattr; + + kattr = container_of(attr, struct kobj_attribute, attr); + if (kattr->show) + return kattr->show(kobj, kattr, buf); + return -EIO; +} + +static ssize_t tlmi_attr_store(struct kobject *kobj, struct attribute *attr, + const char *buf, size_t count) +{ + struct kobj_attribute *kattr; + + kattr = container_of(attr, struct kobj_attribute, attr); + if (kattr->store) + return kattr->store(kobj, kattr, buf, count); + return -EIO; +} + +static const struct sysfs_ops tlmi_kobj_sysfs_ops = { + .show = tlmi_attr_show, + .store = tlmi_attr_store, +}; + +static void tlmi_attr_setting_release(struct kobject *kobj) +{ + struct tlmi_attr_setting *setting = container_of(kobj, struct tlmi_attr_setting, kobj); + + kfree(setting); +} + +static void tlmi_pwd_setting_release(struct kobject *kobj) +{ + struct tlmi_pwd_setting *pwd = container_of(kobj, struct tlmi_pwd_setting, kobj); + + kfree(pwd); +} + +static struct kobj_type tlmi_attr_setting_ktype = { + .release = &tlmi_attr_setting_release, + .sysfs_ops = &tlmi_kobj_sysfs_ops, +}; + +static struct kobj_type tlmi_pwd_setting_ktype = { + .release = &tlmi_pwd_setting_release, + .sysfs_ops = &tlmi_kobj_sysfs_ops, +}; + +/* ---- Initialisation --------------------------------------------------------- */ +static void tlmi_release_attr(void) +{ + int i; + + /* Attribute structures */ + for (i = 0; i < TLMI_SETTINGS_COUNT; i++) { + if (tlmi_priv.setting[i]) { + kfree(tlmi_priv.setting[i]->possible_values); + sysfs_remove_group(&tlmi_priv.setting[i]->kobj, &tlmi_attr_group); + kobject_put(&tlmi_priv.setting[i]->kobj); + } + } + kset_unregister(tlmi_priv.attribute_kset); + + /* Authentication structures */ + sysfs_remove_group(&tlmi_priv.pwd_admin->kobj, &auth_attr_group); + kobject_put(&tlmi_priv.pwd_admin->kobj); + sysfs_remove_group(&tlmi_priv.pwd_power->kobj, &auth_attr_group); + kobject_put(&tlmi_priv.pwd_power->kobj); + kset_unregister(tlmi_priv.authentication_kset); +} + +static int tlmi_sysfs_init(void) +{ + int i, ret; + + ret = fw_attributes_class_get(&fw_attr_class); + if (ret) + return ret; + + tlmi_priv.class_dev = device_create(fw_attr_class, NULL, MKDEV(0, 0), + NULL, "%s", "thinklmi"); + if (IS_ERR(tlmi_priv.class_dev)) { + ret = PTR_ERR(tlmi_priv.class_dev); + goto fail_class_created; + } + + tlmi_priv.attribute_kset = kset_create_and_add("attributes", NULL, + &tlmi_priv.class_dev->kobj); + if (!tlmi_priv.attribute_kset) { + ret = -ENOMEM; + goto fail_device_created; + } + + for (i = 0; i < TLMI_SETTINGS_COUNT; i++) { + /* Check if index is a valid setting - skip if it isn't */ + if (!tlmi_priv.setting[i]) + continue; + + /* Build attribute */ + tlmi_priv.setting[i]->kobj.kset = tlmi_priv.attribute_kset; + ret = kobject_init_and_add(&tlmi_priv.setting[i]->kobj, &tlmi_attr_setting_ktype, + NULL, "%s", tlmi_priv.setting[i]->display_name); + if (ret) + goto fail_create_attr; + + ret = sysfs_create_group(&tlmi_priv.setting[i]->kobj, &tlmi_attr_group); + if (ret) + goto fail_create_attr; + } + + /* Create authentication entries */ + tlmi_priv.authentication_kset = kset_create_and_add("authentication", NULL, + &tlmi_priv.class_dev->kobj); + if (!tlmi_priv.authentication_kset) { + ret = -ENOMEM; + goto fail_create_attr; + } + tlmi_priv.pwd_admin->kobj.kset = tlmi_priv.authentication_kset; + ret = kobject_init_and_add(&tlmi_priv.pwd_admin->kobj, &tlmi_pwd_setting_ktype, + NULL, "%s", "Admin"); + if (ret) + goto fail_create_attr; + + ret = sysfs_create_group(&tlmi_priv.pwd_admin->kobj, &auth_attr_group); + if (ret) + goto fail_create_attr; + + tlmi_priv.pwd_power->kobj.kset = tlmi_priv.authentication_kset; + ret = kobject_init_and_add(&tlmi_priv.pwd_power->kobj, &tlmi_pwd_setting_ktype, + NULL, "%s", "System"); + if (ret) + goto fail_create_attr; + + ret = sysfs_create_group(&tlmi_priv.pwd_power->kobj, &auth_attr_group); + if (ret) + goto fail_create_attr; + + return ret; + +fail_create_attr: + tlmi_release_attr(); +fail_device_created: + device_destroy(fw_attr_class, MKDEV(0, 0)); +fail_class_created: + fw_attributes_class_put(); + return ret; +} + +/* ---- Base Driver -------------------------------------------------------- */ +static int tlmi_analyze(void) +{ + struct tlmi_pwdcfg pwdcfg; + acpi_status status; + int i, ret; + + if (wmi_has_guid(LENOVO_SET_BIOS_SETTINGS_GUID) && + wmi_has_guid(LENOVO_SAVE_BIOS_SETTINGS_GUID)) + tlmi_priv.can_set_bios_settings = true; + + if (wmi_has_guid(LENOVO_GET_BIOS_SELECTIONS_GUID)) + tlmi_priv.can_get_bios_selections = true; + + if (wmi_has_guid(LENOVO_SET_BIOS_PASSWORD_GUID)) + tlmi_priv.can_set_bios_password = true; + + if (wmi_has_guid(LENOVO_BIOS_PASSWORD_SETTINGS_GUID)) + tlmi_priv.can_get_password_settings = true; + + /* + * Try to find the number of valid settings of this machine + * and use it to create sysfs attributes. + */ + for (i = 0; i < TLMI_SETTINGS_COUNT; ++i) { + struct tlmi_attr_setting *setting; + char *item = NULL; + + tlmi_priv.setting[i] = NULL; + status = tlmi_setting(i, &item, LENOVO_BIOS_SETTING_GUID); + if (ACPI_FAILURE(status)) + break; + if (!item) + break; + if (!*item) + continue; + + /* It is not allowed to have '/' for file name. Convert it into '\'. */ + strreplace(item, '/', '\\'); + + /* Remove the value part */ + strreplace(item, ',', '\0'); + + /* Create a setting entry */ + setting = kzalloc(sizeof(struct tlmi_attr_setting), GFP_KERNEL); + if (!setting) { + ret = -ENOMEM; + goto fail_clear_attr; + } + setting->index = i; + strscpy(setting->display_name, item, TLMI_SETTINGS_MAXLEN); + /* If BIOS selections supported, load those */ + if (tlmi_priv.can_get_bios_selections) { + ret = tlmi_get_bios_selections(setting->display_name, + &setting->possible_values); + if (ret || !setting->possible_values) + pr_info("Error retrieving possible values for %d : %s\n", + i, setting->display_name); + } + tlmi_priv.setting[i] = setting; + tlmi_priv.settings_count++; + kfree(item); + } + + /* Create password setting structure */ + ret = tlmi_get_pwd_settings(&pwdcfg); + if (ret) + goto fail_clear_attr; + + tlmi_priv.pwd_admin = kzalloc(sizeof(struct tlmi_pwd_setting), GFP_KERNEL); + if (!tlmi_priv.pwd_admin) { + ret = -ENOMEM; + goto fail_clear_attr; + } + sprintf(tlmi_priv.pwd_admin->display_name, "admin"); + sprintf(tlmi_priv.pwd_admin->kbdlang, "us"); + tlmi_priv.pwd_admin->encoding = TLMI_ENCODING_ASCII; + tlmi_priv.pwd_admin->pwd_type = "pap"; + tlmi_priv.pwd_admin->role = "bios-admin"; + tlmi_priv.pwd_admin->minlen = pwdcfg.min_length; + if (WARN_ON(pwdcfg.max_length >= TLMI_PWD_BUFSIZE)) + pwdcfg.max_length = TLMI_PWD_BUFSIZE - 1; + tlmi_priv.pwd_admin->maxlen = pwdcfg.max_length; + if (pwdcfg.password_state & TLMI_PAP_PWD) + tlmi_priv.pwd_admin->valid = true; + + tlmi_priv.pwd_power = kzalloc(sizeof(struct tlmi_pwd_setting), GFP_KERNEL); + if (!tlmi_priv.pwd_power) { + ret = -ENOMEM; + goto fail_clear_attr; + } + sprintf(tlmi_priv.pwd_power->display_name, "power-on"); + sprintf(tlmi_priv.pwd_power->kbdlang, "us"); + tlmi_priv.pwd_power->encoding = TLMI_ENCODING_ASCII; + tlmi_priv.pwd_power->pwd_type = "pop"; + tlmi_priv.pwd_power->role = "power-on"; + tlmi_priv.pwd_power->minlen = pwdcfg.min_length; + tlmi_priv.pwd_power->maxlen = pwdcfg.max_length; + + if (pwdcfg.password_state & TLMI_POP_PWD) + tlmi_priv.pwd_power->valid = true; + + return 0; + +fail_clear_attr: + for (i = 0; i < TLMI_SETTINGS_COUNT; ++i) + kfree(tlmi_priv.setting[i]); + return ret; +} + +static void tlmi_remove(struct wmi_device *wdev) +{ + tlmi_release_attr(); + device_destroy(fw_attr_class, MKDEV(0, 0)); + fw_attributes_class_put(); +} + +static int tlmi_probe(struct wmi_device *wdev, const void *context) +{ + tlmi_analyze(); + return tlmi_sysfs_init(); +} + +static const struct wmi_device_id tlmi_id_table[] = { + { .guid_string = LENOVO_BIOS_SETTING_GUID }, + { } +}; + +static struct wmi_driver tlmi_driver = { + .driver = { + .name = "think-lmi", + }, + .id_table = tlmi_id_table, + .probe = tlmi_probe, + .remove = tlmi_remove, +}; + +MODULE_AUTHOR("Sugumaran L <slacshiminar@lenovo.com>"); +MODULE_AUTHOR("Mark Pearson <markpearson@lenovo.com>"); +MODULE_AUTHOR("Corentin Chary <corentin.chary@gmail.com>"); +MODULE_DESCRIPTION("ThinkLMI Driver"); +MODULE_LICENSE("GPL"); + +module_wmi_driver(tlmi_driver); diff --git a/drivers/platform/x86/think-lmi.h b/drivers/platform/x86/think-lmi.h new file mode 100644 index 000000000..05005576b --- /dev/null +++ b/drivers/platform/x86/think-lmi.h @@ -0,0 +1,80 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ + +#ifndef _THINK_LMI_H_ +#define _THINK_LMI_H_ + +#define TLMI_SETTINGS_COUNT 256 +#define TLMI_SETTINGS_MAXLEN 512 +#define TLMI_PWD_BUFSIZE 129 +#define TLMI_PWDTYPE_MAXLEN 64 +#define TLMI_ENC_MAXLEN 64 +#define TLMI_LANG_MAXLEN 4 +#define TLMI_PWDTYPE_LEN 4 +/* + * Longest string should be in the set command: allow size of BIOS + * option and choice + */ +#define TLMI_GETSET_MAXLEN (TLMI_SETTINGS_MAXLEN + TLMI_SETTINGS_MAXLEN) + +/* Possible error values */ +struct tlmi_err_codes { + const char *err_str; + int err_code; +}; + +enum encoding_option { + TLMI_ENCODING_ASCII, + TLMI_ENCODING_SCANCODE, +}; + +/* password configuration details */ +struct tlmi_pwdcfg { + uint32_t password_mode; + uint32_t password_state; + uint32_t min_length; + uint32_t max_length; + uint32_t supported_encodings; + uint32_t supported_keyboard; +}; + +/* password setting details */ +struct tlmi_pwd_setting { + struct kobject kobj; + bool valid; + char display_name[TLMI_PWDTYPE_MAXLEN]; + char password[TLMI_PWD_BUFSIZE]; + const char *pwd_type; + const char *role; + int minlen; + int maxlen; + enum encoding_option encoding; + char kbdlang[TLMI_LANG_MAXLEN]; +}; + +/* Attribute setting details */ +struct tlmi_attr_setting { + struct kobject kobj; + int index; + char display_name[TLMI_SETTINGS_MAXLEN]; + char *possible_values; +}; + +struct think_lmi { + struct wmi_device *wmi_device; + + int settings_count; + bool can_set_bios_settings; + bool can_get_bios_selections; + bool can_set_bios_password; + bool can_get_password_settings; + + struct tlmi_attr_setting *setting[TLMI_SETTINGS_COUNT]; + struct device *class_dev; + struct kset *attribute_kset; + struct kset *authentication_kset; + struct tlmi_pwd_setting *pwd_admin; + struct tlmi_pwd_setting *pwd_power; +}; + +#endif /* !_THINK_LMI_H_ */ +

[v4,3/3] platform/x86: think-lmi: Add WMI interface support on Lenovo platforms

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