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authorMark Pearson <markpearson@lenovo.com>2021-05-31 01:31:11 +0300
committerHans de Goede <hdegoede@redhat.com>2021-06-16 18:47:52 +0300
commita40cd7ef22fbb11229cf982920f4ec96c1f49282 (patch)
tree6bd3129edf31dae7981922d8ebc1dc29224e3246 /drivers/platform
parent8a1c379c5a03281295c436faf21b0e4716e5b8a8 (diff)
downloadlinux-a40cd7ef22fbb11229cf982920f4ec96c1f49282.tar.xz
platform/x86: think-lmi: Add WMI interface support on Lenovo platforms
For Lenovo platforms that support a WMI interface to the BIOS add support, using the firmware-attributes class, to allow users to access and modify various BIOS related settings. Signed-off-by: Mark Pearson <markpearson@lenovo.com> Link: https://lore.kernel.org/r/20210530223111.25929-3-markpearson@lenovo.com Reviewed-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Diffstat (limited to 'drivers/platform')
-rw-r--r--drivers/platform/x86/Kconfig11
-rw-r--r--drivers/platform/x86/Makefile1
-rw-r--r--drivers/platform/x86/think-lmi.c891
-rw-r--r--drivers/platform/x86/think-lmi.h81
4 files changed, 984 insertions, 0 deletions
diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig
index d6fa071d78de..1e538ce8feaf 100644
--- a/drivers/platform/x86/Kconfig
+++ b/drivers/platform/x86/Kconfig
@@ -640,6 +640,17 @@ 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 98c776967fa0..ff620d653d39 100644
--- a/drivers/platform/x86/Makefile
+++ b/drivers/platform/x86/Makefile
@@ -63,6 +63,7 @@ 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 000000000000..854427fed1a9
--- /dev/null
+++ b/drivers/platform/x86/think-lmi.c
@@ -0,0 +1,891 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * 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/errno.h>
+#include <linux/fs.h>
+#include <linux/string.h>
+#include <linux/types.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,pa55w0rd,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:
+ * "pa55w0rd,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,pa55w0rd,newpa55w0rd,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)
+#define to_tlmi_pwd_setting(kobj) container_of(kobj, struct tlmi_pwd_setting, kobj)
+#define to_tlmi_attr_setting(kobj) container_of(kobj, struct tlmi_attr_setting, kobj)
+
+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)
+ 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)
+ 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 = to_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 = to_tlmi_pwd_setting(kobj);
+ size_t pwdlen;
+ char *p;
+
+ pwdlen = strlen(buf);
+ /* pwdlen == 0 is allowed to clear the password */
+ if (pwdlen && ((pwdlen < setting->minlen) || (pwdlen > setting->maxlen)))
+ return -EINVAL;
+
+ strscpy(setting->password, buf, setting->maxlen);
+ /* Strip out CR if one is present, setting password won't work if it is present */
+ p = strchrnul(setting->password, '\n');
+ *p = '\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 = to_tlmi_pwd_setting(kobj);
+ char *auth_str, *new_pwd, *p;
+ size_t pwdlen;
+ int ret;
+
+ 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 */
+ p = strchrnul(new_pwd, '\n');
+ *p = '\0';
+
+ pwdlen = strlen(new_pwd);
+ /* pwdlen == 0 is allowed to clear the password */
+ if (pwdlen && ((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 = to_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 = to_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 = to_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 = to_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 = to_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 = to_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 = to_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 = to_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 = to_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 = to_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 = to_tlmi_attr_setting(kobj);
+ char *set_str = NULL, *new_setting = NULL;
+ char *auth_str = NULL;
+ char *p;
+ 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 */
+ p = strchrnul(new_setting, '\n');
+ *p = '\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 = to_tlmi_attr_setting(kobj);
+
+ kfree(setting);
+}
+
+static void tlmi_pwd_setting_release(struct kobject *kobj)
+{
+ struct tlmi_pwd_setting *setting = to_tlmi_pwd_setting(kobj);
+
+ kfree(setting);
+}
+
+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;
+ char *p;
+
+ 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 */
+ p = strchrnul(item, ',');
+ *p = '\0';
+
+ /* Create a setting entry */
+ setting = kzalloc(sizeof(*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;
+ }
+ strscpy(tlmi_priv.pwd_admin->display_name, "admin", TLMI_PWDTYPE_MAXLEN);
+ strscpy(tlmi_priv.pwd_admin->kbdlang, "us", TLMI_LANG_MAXLEN);
+ 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;
+ }
+ strscpy(tlmi_priv.pwd_power->display_name, "power-on", TLMI_PWDTYPE_MAXLEN);
+ strscpy(tlmi_priv.pwd_power->kbdlang, "us", TLMI_LANG_MAXLEN);
+ 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 000000000000..6cd5325cc50e
--- /dev/null
+++ b/drivers/platform/x86/think-lmi.h
@@ -0,0 +1,81 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+
+#ifndef _THINK_LMI_H_
+#define _THINK_LMI_H_
+
+#include <linux/types.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_ */