Re: [PATCH v2] Introduce support for Systems Management Driver over WMI for Dell Systems

From: mark gross
Date: Fri Sep 11 2020 - 14:31:49 EST

On Fri, Sep 04, 2020 at 07:58:46PM +0530, Divya Bharathi wrote:
> The Dell WMI Systems Management Driver provides a sysfs
> interface for systems management to enable BIOS configuration
> capability on certain Dell Systems.
>
> This driver allows user to configure Dell systems with a
> uniform common interface. To facilitate this, the patch
> introduces a generic way for driver to be able to create
> configurable BIOS Attributes available in Setup (F2) screen.
>
> Cc: Hans de Goede <hdegoede@xxxxxxxxxx>
> Cc: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>
>
> Co-developed-by: Mario Limonciello <mario.limonciello@xxxxxxxx>
> Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxxx>
> Co-developed-by: Prasanth KSR <prasanth.ksr@xxxxxxxx>
> Signed-off-by: Prasanth KSR <prasanth.ksr@xxxxxxxx>
> Signed-off-by: Divya Bharathi <divya_bharathi@xxxxxxxx>
> ---
>
> ChangeLog from v1 to v2:
> - use pr_fmt instead of pr_err(DRIVER_NAME
> - re-order variables reverse xmas tree order
> - correct returns of -1 to error codes
> - correct usage of {} on some split line statements
> - Refine all documentation deficiencies suggested by Hans
> - Merge all attributes to a single directory
> - Overhaul WMI interface interaction as suggested by Hans
> * Move WMI driver registration to start of module
> * Remove usage of lists that only use first entry for WMI interfaces
> * Create a global structure shared across interface source files
> * Make get_current_password function static
> * Remove get_pending changes function, shared across global structure now.
> - Overhaul use of mutexes
> * Make kset list mutex shared across source files
> * Remove unneeded dell-wmi-sysman call_mutex
> * Keep remaining call_mutexes in WMI functions
> - Move security area calculation into a function
> - Use NLS helper for utf8->utf16 conversion
>
> .../testing/sysfs-platform-dell-wmi-sysman | 126 ++++
> MAINTAINERS | 9 +
> drivers/platform/x86/Kconfig | 12 +
> drivers/platform/x86/Makefile | 8 +
> .../x86/dell-wmi-biosattr-interface.c | 198 ++++++
> .../platform/x86/dell-wmi-enum-attributes.c | 214 +++++++
> .../platform/x86/dell-wmi-int-attributes.c | 195 ++++++
> .../x86/dell-wmi-passobj-attributes.c | 168 +++++
> .../x86/dell-wmi-passwordattr-interface.c | 200 ++++++
> .../platform/x86/dell-wmi-string-attributes.c | 177 ++++++
> .../platform/x86/dell-wmi-sysman-attributes.c | 572 ++++++++++++++++++
> .../platform/x86/dell-wmi-sysman-attributes.h | 132 ++++
> 12 files changed, 2011 insertions(+)
> create mode 100644 Documentation/ABI/testing/sysfs-platform-dell-wmi-sysman
> create mode 100644 drivers/platform/x86/dell-wmi-biosattr-interface.c
> create mode 100644 drivers/platform/x86/dell-wmi-enum-attributes.c
> create mode 100644 drivers/platform/x86/dell-wmi-int-attributes.c
> create mode 100644 drivers/platform/x86/dell-wmi-passobj-attributes.c
> create mode 100644 drivers/platform/x86/dell-wmi-passwordattr-interface.c
> create mode 100644 drivers/platform/x86/dell-wmi-string-attributes.c
> create mode 100644 drivers/platform/x86/dell-wmi-sysman-attributes.c
> create mode 100644 drivers/platform/x86/dell-wmi-sysman-attributes.h
>
> diff --git a/Documentation/ABI/testing/sysfs-platform-dell-wmi-sysman b/Documentation/ABI/testing/sysfs-platform-dell-wmi-sysman
> new file mode 100644
> index 000000000000..e4b608275ea4
> --- /dev/null
> +++ b/Documentation/ABI/testing/sysfs-platform-dell-wmi-sysman
> @@ -0,0 +1,126 @@
> +What: /sys/devices/platform/dell-wmi-sysman/attributes/
> +Date: December 2020
> +KernelVersion: 5.10
> +Contact: Divya Bharathi <Divya.Bharathi@xxxxxxxx>,
> + Mario Limonciello <mario.limonciello@xxxxxxxx>,
> + Prasanth KSR <prasanth.ksr@xxxxxxxx>
> +Description:
> + The Dell WMI Systems Management Driver provides a sysfs interface
> + for systems management software to enable BIOS configuration
> + capability on certain Dell systems. This directory exposes
> + interfaces for interacting with BIOS attributes.
> +
> + Attributes can accept a set of pre-defined valid values or a range of
> + numerical values or a string. An atribute can accept float as well,
> + if so '.' is used as decimal separator.
> +
> + Also, BIOS Admin password and System Password can be set, reset or
> + cleared using these attributes. An "Admin" password is used for
> + preventing modification to the BIOS settings. A "System" password is
> + required to boot a machine.
> +
> + current_value: A file that can be read to obtain the current
> + value of the <attr>
> +
> + This file can also be written to in order to update
> + the value of a <attr>
> +
> + default_value: A file that can be read to obtain the default
> + value of the <attr>
> +
> + display_name: A file that can be read to obtain a user friendly
> + description of the at <attr>
> +
> + display_name_language_code: A file that can be read to obtain
> + the IETF language tag corresponding to the "display_name" of the <attr>
> +
> + modifier: A file that can be read to obtain attribute-level
> + dependency rule. It says an attribute X will become read-only or
> + suppressed, if attribute Y is not configured.
> + For example, AutoOnHr becomes read-only if AutoOn is disabled
> +
> + possible_value: A file that can be read to obtain the possible
> + values of the <attr>. Values are separated using semi-colon.
> +
> + value_modifier: A file that can be read to obtain value-level
> + dependency. This file is similar to modifier but here, an attribute's
> + current value will be forcefully changed based dependent attributes
> + value.
> + For example, current value of LegacyOrom will become Disabled if
> + SecureBoot is Enabled.
> +
> + lower_bound: A file that can be read to obtain the lower
> + bound value of the <attr>
> +
> + upper_bound: A file that can be read to obtain the upper
> + bound value of the <attr>
> +
> + scalar_increment: A file that can be read to obtain the
> + resolution of the incremental value this attribute accepts.
> +
> + max_length: A file that can be read to obtain the maximum
> + length value of the <attr>
> +
> + min_length: A file that can be read to obtain the minimum
> + length value of the <attr>
> +
> + is_password_set: A file that can be read
> + to obtain flag to see if a password is set on <attr>
> +
> + max_password_length: A file that can be read to obtain the
> + maximum length of the Password
> +
> + min_password_length: A file that can be read to obtain the
> + minimum length of the Password
> +
> + current_password: A write only value used for privileged access
> + such as setting attributes when a system or admin password is set
> + or resetting to a new password
> +
> + new_password: A write only value that when used in tandem with
> + current_password will reset a system or admin password.
> +
> +What: /sys/devices/platform/dell-wmi-sysman/attributes/reset_bios
> +Date: December 2020
> +KernelVersion: 5.10
> +Contact: Divya Bharathi <Divya.Bharathi@xxxxxxxx>,
> + Mario Limonciello <mario.limonciello@xxxxxxxx>,
> + Prasanth KSR <prasanth.ksr@xxxxxxxx>
> +Description:
> + This attribute can be used to reset the BIOS Configuration.
> + Specifically, it tells which type of reset BIOS configuration is being
> + requested on the host.
> +
> + Reading from it returns a list of supported options encoded as:
> +
> + 'builtinsafe' (Built in safe configuration profile)
> + 'lastknowngood' (Last known good saved configuration profile)
> + 'factory' (Default factory settings configuration profile)
> + 'custom' (Custom saved configuration profile)
> +
> + The currently selected option is printed in square brackets as
> + shown below:
> +
> + # echo "factory" > sys/devices/platform/dell-wmi-sysman/attributes/reset_bios
> +
> + # cat sys/devices/platform/dell-wmi-sysman/attributes/reset_bios
> + # builtinsafe lastknowngood [factory] custom
> +
> + Note that any changes to this attribute requires a reboot
> + for changes to take effect.
> +
> +What: /sys/devices/platform/dell-wmi-sysman/attributes/pending_reboot
> +Date: December 2020
> +KernelVersion: 5.10
> +Contact: Divya Bharathi <Divya.Bharathi@xxxxxxxx>,
> + Mario Limonciello <mario.limonciello@xxxxxxxx>,
> + Prasanth KSR <prasanth.ksr@xxxxxxxx>
> +Description:
> + A read-only attribute reads 1 if a reboot is necessary to apply
> + pending BIOS attribute changes.
> +
> + 0: All BIOS attributes setting are current
> + 1: A reboot is necessary to get pending BIOS attribute changes
> + applied
> +
> +
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 592467ba3f4d..36ca5671a62d 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -4940,6 +4940,15 @@ M: Mario Limonciello <mario.limonciello@xxxxxxxx>
> S: Maintained
> F: drivers/platform/x86/dell-wmi-descriptor.c
>
> +DELL WMI SYSMAN DRIVER
> +M: Divya Bharathi <divya.bharathi@xxxxxxxx>
> +M: Mario Limonciello <mario.limonciello@xxxxxxxx>
> +M: Prasanth Ksr <prasanth.ksr@xxxxxxxx>
> +L: platform-driver-x86@xxxxxxxxxxxxxxx
> +S: Maintained
> +F: drivers/platform/x86/dell-wmi-*-attributes.*
> +F: drivers/platform/x86/dell-wmi-*-interface.c
> +
> DELL WMI NOTIFICATIONS DRIVER
> M: Matthew Garrett <mjg59@xxxxxxxxxxxxx>
> M: Pali Rohár <pali@xxxxxxxxxx>
> diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig
> index 40219bba6801..80646b328d72 100644
> --- a/drivers/platform/x86/Kconfig
> +++ b/drivers/platform/x86/Kconfig
> @@ -430,6 +430,18 @@ config DELL_WMI
> To compile this driver as a module, choose M here: the module will
> be called dell-wmi.
>
> +config DELL_WMI_SYSMAN
> + tristate "Dell WMI SYSMAN"
> + depends on ACPI_WMI
> + depends on DMI
> + select NLS
> + help
> + This driver allows changing BIOS settings on many Dell machines from
> + 2018 and newer without the use of any additional software.
> +
> + To compile this driver as a module, choose M here: the module will
> + be called dell-wmi-sysman.
> +
> config DELL_WMI_DESCRIPTOR
> tristate
> depends on ACPI_WMI
> diff --git a/drivers/platform/x86/Makefile b/drivers/platform/x86/Makefile
> index 5f823f7eff45..dc2ccb574192 100644
> --- a/drivers/platform/x86/Makefile
> +++ b/drivers/platform/x86/Makefile
> @@ -47,6 +47,14 @@ obj-$(CONFIG_DELL_WMI) += dell-wmi.o
> obj-$(CONFIG_DELL_WMI_DESCRIPTOR) += dell-wmi-descriptor.o
> obj-$(CONFIG_DELL_WMI_AIO) += dell-wmi-aio.o
> obj-$(CONFIG_DELL_WMI_LED) += dell-wmi-led.o
> +obj-$(CONFIG_DELL_WMI_SYSMAN) += dell-wmi-sysman.o
> +dell-wmi-sysman-objs := dell-wmi-sysman-attributes.o \
> + dell-wmi-enum-attributes.o \
> + dell-wmi-int-attributes.o \
> + dell-wmi-string-attributes.o \
> + dell-wmi-passobj-attributes.o \
> + dell-wmi-passwordattr-interface.o \
> + dell-wmi-biosattr-interface.o
>
> # Fujitsu
> obj-$(CONFIG_AMILO_RFKILL) += amilo-rfkill.o
> diff --git a/drivers/platform/x86/dell-wmi-biosattr-interface.c b/drivers/platform/x86/dell-wmi-biosattr-interface.c
> new file mode 100644
> index 000000000000..dda38d448fec
> --- /dev/null
> +++ b/drivers/platform/x86/dell-wmi-biosattr-interface.c
> @@ -0,0 +1,198 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Functions corresponding to SET methods under BIOS attributes interface GUID for use
> + * with dell-wmi-sysman
> + *
> + * Copyright (c) 2020 Dell Inc.
> + */
> +
> +#include <linux/nls.h>
> +#include <linux/wmi.h>
> +#include "dell-wmi-sysman-attributes.h"
> +
> +#define SETDEFAULTVALUES_METHOD_ID 0x02
> +#define SETBIOSDEFAULTS_METHOD_ID 0x03
> +#define SETATTRIBUTE_METHOD_ID 0x04
> +
> +static DEFINE_MUTEX(call_mutex);
> +
> +extern struct dell_wmi_sysman_priv wmi_priv;
> +
> +static int call_biosattributes_interface(struct wmi_device *wdev, char *in_args, size_t size,
> + int method_id)
> +{
> + struct acpi_buffer output = {ACPI_ALLOCATE_BUFFER, NULL};
> + struct acpi_buffer input;
> + union acpi_object *obj;
> + acpi_status status;
> + int ret = -EIO;
> +
> + input.length = (acpi_size) size;
> + input.pointer = in_args;
> + status = wmidev_evaluate_method(wdev, 0, method_id, &input, &output);
> + if (ACPI_FAILURE(status))
> + return -EIO;
> + obj = (union acpi_object *)output.pointer;
> + if (obj->type == ACPI_TYPE_INTEGER)
> + ret = obj->integer.value;
> +
> + kfree(output.pointer);
> + kobject_uevent(&wdev->dev.kobj, KOBJ_CHANGE);
> + return map_wmi_error(ret);
> +}
> +
> +/**
> + * set_attribute() - Update an attribute value
> + * @a_name: The attribute name
> + * @a_value: The attribute value
> + *
> + * Sets an attribute to new value
> + **/
> +int set_attribute(const char *a_name, const char *a_value)
> +{
> + size_t security_area_size, string_area_size, buffer_size;
> + char *attribute_name, *attribute_value;
> + u8 *name_len, *value_len;
> + char *buffer;
> + int ret;
> +
> + /* build/calculate buffer */
> + security_area_size = calculate_security_buffer();
> + string_area_size = (strlen(a_name) + strlen(a_value))*2;
> + buffer_size = security_area_size + string_area_size + sizeof(u16) * 2;
> + buffer = kzalloc(buffer_size, GFP_KERNEL);
> + if (!buffer)
> + return -ENOMEM;
> +
> + /* build security area */
> + if (strlen(wmi_priv.current_admin_password) > 0)
> + populate_security_buffer(buffer, wmi_priv.current_admin_password);
> +
> + /* build variables to set */
> + name_len = buffer + security_area_size;
> + attribute_name = name_len + sizeof(u16);
> + *name_len = utf8s_to_utf16s(a_name, strlen(a_name), UTF16_HOST_ENDIAN,
> + (wchar_t *) attribute_name, MAX_BUFF) * 2;
> + if (*name_len < 0) {
> + ret = -EINVAL;
> + pr_err("UTF16 conversion failed");
> + goto out_set_attribute;
> + }
> +
> + value_len = (u8 *) attribute_name + *name_len;
> + attribute_value = value_len + sizeof(u16);
> + *value_len = utf8s_to_utf16s(a_value, strlen(a_value), UTF16_HOST_ENDIAN,
> + (wchar_t *) attribute_value, MAX_BUFF) * 2;
> + if (*value_len < 0) {
> + ret = -EINVAL;
> + pr_err("UTF16 conversion failed");
> + goto out_set_attribute;
> + }
> +
> + mutex_lock(&call_mutex);
> + if (!wmi_priv.bios_attr_wdev) {
> + ret = -ENODEV;
> + pr_err("no WMI backend bound");
> + goto out_set_attribute;
> + }
> +
> + ret = call_biosattributes_interface(wmi_priv.bios_attr_wdev,
> + buffer, buffer_size,
> + SETATTRIBUTE_METHOD_ID);
> + if (ret == -EOPNOTSUPP)
> + dev_err(&wmi_priv.password_attr_wdev->dev, "admin password must be configured");
> + else if (ret == -EACCES)
> + dev_err(&wmi_priv.password_attr_wdev->dev, "invalid password");
> +
> + wmi_priv.pending_changes = 1;
> +out_set_attribute:
> + kfree(buffer);
> + mutex_unlock(&call_mutex);
> +
> + return ret;
> +}
> +
> +/**
> + * set_bios_defaults() - Resets BIOS defaults
> + * @deftype: the type of BIOS value reset to issue.
> + *
> + * Resets BIOS defaults
> + **/
> +int set_bios_defaults(u8 deftype)
> +{
> + size_t security_area_size, buffer_size;
> + size_t integer_area_size = sizeof(u8);
> + u8 *defaultType;
> + char *buffer;
> + int ret;
> +
> + security_area_size = calculate_security_buffer();
> + buffer_size = security_area_size + integer_area_size;
> + buffer = kzalloc(buffer_size, GFP_KERNEL);
> + if (!buffer)
> + return -ENOMEM;
> +
> + /* build security area */
> + if (strlen(wmi_priv.current_admin_password) > 0)
> + populate_security_buffer(buffer, wmi_priv.current_admin_password);
> +
> + mutex_lock(&call_mutex);
> + if (!wmi_priv.bios_attr_wdev) {
> + ret = -ENODEV;
> + pr_err("no WMI backend bound");
> + goto out_bios_defaults;
> + }
> +
> + defaultType = buffer + security_area_size;
> + *defaultType = deftype;
> +
> + ret = call_biosattributes_interface(wmi_priv.bios_attr_wdev, buffer, buffer_size,
> + SETBIOSDEFAULTS_METHOD_ID);
> + if (ret)
> + dev_err(&wmi_priv.bios_attr_wdev->dev, "reset BIOS defaults failed: %d", ret);
> + wmi_priv.pending_changes = 1;
> +out_bios_defaults:
> + kfree(buffer);
> + mutex_unlock(&call_mutex);
> +
> + return ret;
> +}
> +
> +static int dell_wmi_bios_attr_set_interface_probe(struct wmi_device *wdev, const void *context)
> +{
> + wmi_priv.bios_attr_wdev = wdev;
> + return 0;
> +}
> +
> +static int dell_wmi_bios_attr_set_interface_remove(struct wmi_device *wdev)
> +{
> + mutex_lock(&call_mutex);
> + wmi_priv.bios_attr_wdev = NULL;
> + mutex_unlock(&call_mutex);
> + return 0;
> +}
> +
> +static const struct wmi_device_id dell_wmi_bios_attr_set_interface_id_table[] = {
> + { .guid_string = DELL_WMI_BIOS_ATTRIBUTES_INTERFACE_GUID },
> + { },
> +};
> +static struct wmi_driver dell_wmi_bios_attr_set_interface_driver = {
> + .driver = {
> + .name = DRIVER_NAME"-set"
> + },
> + .probe = dell_wmi_bios_attr_set_interface_probe,
> + .remove = dell_wmi_bios_attr_set_interface_remove,
> + .id_table = dell_wmi_bios_attr_set_interface_id_table,
> +};
> +
> +int init_dell_wmi_bios_attr_set_interface(void)
> +{
> + return wmi_driver_register(&dell_wmi_bios_attr_set_interface_driver);
> +}
> +
> +void exit_dell_wmi_bios_attr_set_interface(void)
> +{
> + wmi_driver_unregister(&dell_wmi_bios_attr_set_interface_driver);
> +}
> +
> +MODULE_DEVICE_TABLE(wmi, dell_wmi_bios_attr_set_interface_id_table);
> diff --git a/drivers/platform/x86/dell-wmi-enum-attributes.c b/drivers/platform/x86/dell-wmi-enum-attributes.c
> new file mode 100644
> index 000000000000..f2370f067b6d
> --- /dev/null
> +++ b/drivers/platform/x86/dell-wmi-enum-attributes.c
> @@ -0,0 +1,214 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Functions corresponding to enumeration type attributes under BIOS Enumeration GUID for use
> + * with dell-wmi-sysman
> + *
> + * Copyright (c) 2020 Dell Inc.
> + */
> +
> +#include "dell-wmi-sysman-attributes.h"
> +
> +static DEFINE_MUTEX(enum_mutex);
> +extern struct mutex kset_mutex;
> +
> +/* kept variable names same as in sysfs file name for sysfs_show macro definition */
> +struct enumeration_data {
> + char display_name_language_code[MAX_BUFF];
> + char attribute_name[MAX_BUFF];
> + char display_name[MAX_BUFF];
> + char default_value[MAX_BUFF];
> + char current_value[MAX_BUFF];
> + char modifier[MAX_BUFF];
> + int value_modifier_count;
> + char value_modifier[MAX_BUFF];
> + int possible_value_count;
> + char possible_value[MAX_BUFF];
> + char type[MAX_BUFF];
> +};
> +
> +static struct enumeration_data *enumeration_data;
> +static int enumeration_instances_count;
> +get_instance_id(enumeration);
> +
> +static ssize_t current_value_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
> +{
> + int instance_id;
> +
> + if (!capable(CAP_SYS_ADMIN))
> + return -EPERM;
> + instance_id = get_enumeration_instance_id(kobj);
> + if (instance_id >= 0) {
> + union acpi_object *obj;
> +
> + obj = get_wmiobj_pointer(instance_id, DELL_WMI_BIOS_ENUMERATION_ATTRIBUTE_GUID);
> + if (!obj)
> + return -AE_ERROR;
> + strncpy_attr(enumeration_data[instance_id].current_value,
> + obj->package.elements[CURRENT_VAL].string.pointer);
> + kfree(obj);
> + return sprintf(buf, "%s\n", enumeration_data[instance_id].current_value);
> + }
> + return -EIO;
> +}
> +
> +/**
> + * validate_enumeration_input() - Validate input of current_value against possible values
> + * @instance_id: The instance on which input is validated
> + * @buf: Input value
> + **/
> +int validate_enumeration_input(int instance_id, const char *buf)
> +{
> + char *options, *tmp, *p;
> + int ret = -EINVAL;
> +
> + options = tmp = kstrdup((enumeration_data[instance_id].possible_value), GFP_KERNEL);
> + if (!options)
> + return -ENOMEM;
> +
> + while ((p = strsep(&options, ";")) != NULL) {
> + if (!*p)
> + continue;
> + if (!strncasecmp(p, buf, strlen(p))) {
> + ret = 0;
> + break;
> + }
> + }
> +
> + kfree(tmp);
> + return ret;
> +}
> +
> +attribute_s_property_show(display_name_language_code, enumeration);
> +static struct kobj_attribute displ_langcode =
> + __ATTR_RO(display_name_language_code);
> +
> +attribute_s_property_show(display_name, enumeration);
> +struct kobj_attribute displ_name =
> + __ATTR_RO(display_name);
> +
> +attribute_s_property_show(default_value, enumeration);
> +struct kobj_attribute default_val =
> + __ATTR_RO(default_value);
> +
> +attribute_property_store(current_value, enumeration);
> +struct kobj_attribute current_val =
> + __ATTR_RW(current_value);
> +
> +attribute_s_property_show(modifier, enumeration);
> +struct kobj_attribute modifier =
> + __ATTR_RO(modifier);
> +
> +attribute_s_property_show(value_modifier, enumeration);
> +struct kobj_attribute value_modfr =
> + __ATTR_RO(value_modifier);
> +
> +attribute_s_property_show(possible_value, enumeration);
> +struct kobj_attribute poss_val =
> + __ATTR_RO(possible_value);
> +
> +attribute_s_property_show(type, enumeration);
> +struct kobj_attribute type =
> + __ATTR_RO(type);
> +
> +static struct attribute *enumeration_attrs[] = {
> + &displ_langcode.attr,
> + &displ_name.attr,
> + &default_val.attr,
> + &current_val.attr,
> + &modifier.attr,
> + &value_modfr.attr,
> + &poss_val.attr,
> + &type.attr,
> + NULL,
> +};
> +
> +static const struct attribute_group enumeration_attr_group = {
> + .attrs = enumeration_attrs,
> +};
> +
> +int alloc_enum_data(void)
> +{
> + int ret = 0;
> +
> + enumeration_instances_count = get_instance_count(DELL_WMI_BIOS_ENUMERATION_ATTRIBUTE_GUID);
> + enumeration_data = kzalloc((sizeof(struct enumeration_data) * enumeration_instances_count),
> + GFP_KERNEL);
> + if (!enumeration_data)
> + ret = -ENOMEM;
> + return ret;
> +}
> +
> +/**
> + * populate_enum_data() - Populate all properties of an instance under enumeration attribute
> + * @enumeration_obj: ACPI object with enumeration data
> + * @instance_id: The instance to enumerate
> + * @attr_name_kobj: The parent kernel object
> + **/
> +int populate_enum_data(union acpi_object *enumeration_obj, int instance_id,
> + struct kobject *attr_name_kobj)
> +{
> + int retval = sysfs_create_group(attr_name_kobj, &enumeration_attr_group);
> + int i, next_obj;
> +
> + if (retval)
> + goto out;
> +
> + mutex_lock(&enum_mutex);
> + strncpy_attr(enumeration_data[instance_id].attribute_name,
> + enumeration_obj[ATTR_NAME].string.pointer);
> + strncpy_attr(enumeration_data[instance_id].display_name_language_code,
> + enumeration_obj[DISPL_NAME_LANG_CODE].string.pointer);
> + strncpy_attr(enumeration_data[instance_id].display_name,
> + enumeration_obj[DISPLAY_NAME].string.pointer);
> + strncpy_attr(enumeration_data[instance_id].default_value,
> + enumeration_obj[DEFAULT_VAL].string.pointer);
> + strncpy_attr(enumeration_data[instance_id].current_value,
> + enumeration_obj[CURRENT_VAL].string.pointer);
> + strncpy_attr(enumeration_data[instance_id].modifier,
> + enumeration_obj[MODIFIER].string.pointer);
> +
> + next_obj = MODIFIER + 1;
> +
> + enumeration_data[instance_id].value_modifier_count =
> + (uintptr_t)enumeration_obj[next_obj].string.pointer;
> +
> + for (i = 0; i < enumeration_data[instance_id].value_modifier_count; i++) {
> + strcat(enumeration_data[instance_id].value_modifier,
> + enumeration_obj[++next_obj].string.pointer);
> + strcat(enumeration_data[instance_id].value_modifier, ";");
> + }
> +
> + enumeration_data[instance_id].possible_value_count =
> + (uintptr_t) enumeration_obj[++next_obj].string.pointer;
> +
> + for (i = 0; i < enumeration_data[instance_id].possible_value_count; i++) {
> + strcat(enumeration_data[instance_id].possible_value,
> + enumeration_obj[++next_obj].string.pointer);
> + strcat(enumeration_data[instance_id].possible_value, ";");
> + }
> + strncpy_attr(enumeration_data[instance_id].type, "enumeration");
> + mutex_unlock(&enum_mutex);
> +
> +out:
> + return retval;
> +}
> +
> +/**
> + * exit_enum_attributes() - Clear all attribute data
> + * @kset: The kset to free
> + *
> + * Clears all data allocated for this group of attributes
> + **/
> +void exit_enum_attributes(struct kset *kset)
> +{
> + struct kobject *pos, *next;
> +
> + mutex_lock(&kset_mutex);
> + list_for_each_entry_safe(pos, next, &kset->list, entry) {
> + sysfs_remove_group(pos, &enumeration_attr_group);
> + }
> + mutex_unlock(&kset_mutex);
> + mutex_lock(&enum_mutex);
> + kfree(enumeration_data);
> + mutex_unlock(&enum_mutex);
> +}
> diff --git a/drivers/platform/x86/dell-wmi-int-attributes.c b/drivers/platform/x86/dell-wmi-int-attributes.c
> new file mode 100644
> index 000000000000..d922d4f73ce9
> --- /dev/null
> +++ b/drivers/platform/x86/dell-wmi-int-attributes.c
> @@ -0,0 +1,195 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Functions corresponding to integer type attributes under BIOS Integer GUID for use with
> + * dell-wmi-sysman
> + *
> + * Copyright (c) 2020 Dell Inc.
> + */
> +
> +#include "dell-wmi-sysman-attributes.h"
> +
> +static DEFINE_MUTEX(int_mutex);
> +extern struct mutex kset_mutex;
> +
> +enum int_properties {LOWER_BOUND = 6, UPPER_BOUND, SCALAR_INCR};
> +
> +/* kept variable names same as in sysfs file name for sysfs_show macro definition */
> +struct integer_data {
> + char display_name_language_code[MAX_BUFF];
> + char attribute_name[MAX_BUFF];
> + char display_name[MAX_BUFF];
> + int default_value;
> + int current_value;
> + char modifier[MAX_BUFF];
> + int lower_bound;
> + int upper_bound;
> + int scalar_increment;
> + char type[MAX_BUFF];
> +};
> +
> +static struct integer_data *integer_data;
> +static int integer_instances_count;
> +get_instance_id(integer);
> +
> +static ssize_t current_value_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
> +{
> + int instance_id;
> +
> + if (!capable(CAP_SYS_ADMIN))
> + return -EPERM;
> + instance_id = get_integer_instance_id(kobj);
> + if (instance_id >= 0) {
> + union acpi_object *obj;
> +
> + obj = get_wmiobj_pointer(instance_id, DELL_WMI_BIOS_INTEGER_ATTRIBUTE_GUID);
> + if (!obj)
> + return -AE_ERROR;
> + integer_data[instance_id].current_value =
> + (uintptr_t)obj->package.elements[CURRENT_VAL].string.pointer;
> + kfree(obj);
> + return sprintf(buf, "%d\n", integer_data[instance_id].current_value);
> + }
> + return -EIO;
> +}
> +
> +/**
> + * 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
> + **/
> +int validate_integer_input(int instance_id, const char *buf)
> +{
> + int ret = -EINVAL;
> + int in_val;
> +
> + if (kstrtoint(buf, 0, &in_val))
> + return ret;
> + if ((in_val >= integer_data[instance_id].lower_bound) &&
> + (in_val <= integer_data[instance_id].upper_bound))
> + ret = 0;
> +
> + return ret;
> +}
> +
> +attribute_s_property_show(display_name_language_code, integer);
> +static struct kobj_attribute integer_displ_langcode =
> + __ATTR_RO(display_name_language_code);
> +
> +attribute_s_property_show(display_name, integer);
> +struct kobj_attribute integer_displ_name =
> + __ATTR_RO(display_name);
> +
> +attribute_n_property_show(default_value, integer);
> +struct kobj_attribute integer_default_val =
> + __ATTR_RO(default_value);
> +
> +attribute_property_store(current_value, integer);
> +struct kobj_attribute integer_current_val =
> + __ATTR_RW(current_value);
> +
> +attribute_s_property_show(modifier, integer);
> +struct kobj_attribute integer_modifier =
> + __ATTR_RO(modifier);
> +
> +attribute_n_property_show(lower_bound, integer);
> +struct kobj_attribute integer_lower_bound =
> + __ATTR_RO(lower_bound);
> +
> +attribute_n_property_show(upper_bound, integer);
> +struct kobj_attribute integer_upper_bound =
> + __ATTR_RO(upper_bound);
> +
> +attribute_n_property_show(scalar_increment, integer);
> +struct kobj_attribute integer_scalar_increment =
> + __ATTR_RO(scalar_increment);
> +
> +attribute_s_property_show(type, integer);
> +struct kobj_attribute integer_type =
> + __ATTR_RO(type);
> +
> +static struct attribute *integer_attrs[] = {
> + &integer_displ_langcode.attr,
> + &integer_displ_name.attr,
> + &integer_default_val.attr,
> + &integer_current_val.attr,
> + &integer_modifier.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 alloc_int_data(void)
> +{
> + int ret = 0;
> +
> + integer_instances_count = get_instance_count(DELL_WMI_BIOS_INTEGER_ATTRIBUTE_GUID);
> + integer_data = kzalloc((sizeof(struct integer_data) * integer_instances_count), GFP_KERNEL);
> + if (!integer_data)
> + ret = -ENOMEM;
> + return ret;
> +}
> +
> +/**
> + * populate_enum_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 populate_int_data(union acpi_object *integer_obj, int instance_id,
> + struct kobject *attr_name_kobj)
> +{
> + int retval = sysfs_create_group(attr_name_kobj, &integer_attr_group);
> +
> + if (retval)
> + goto out;
> +
> + mutex_lock(&int_mutex);
> + strncpy_attr(integer_data[instance_id].attribute_name,
> + integer_obj[ATTR_NAME].string.pointer);
> + strncpy_attr(integer_data[instance_id].display_name_language_code,
> + integer_obj[DISPL_NAME_LANG_CODE].string.pointer);
> + strncpy_attr(integer_data[instance_id].display_name,
> + integer_obj[DISPLAY_NAME].string.pointer);
> + integer_data[instance_id].default_value =
> + (uintptr_t)integer_obj[DEFAULT_VAL].string.pointer;
> + integer_data[instance_id].current_value =
> + (uintptr_t)integer_obj[CURRENT_VAL].string.pointer;
> + strncpy_attr(integer_data[instance_id].modifier, integer_obj[MODIFIER].string.pointer);
> + integer_data[instance_id].lower_bound =
> + (uintptr_t)integer_obj[LOWER_BOUND].string.pointer;
> + integer_data[instance_id].upper_bound =
> + (uintptr_t)integer_obj[UPPER_BOUND].string.pointer;
> + integer_data[instance_id].scalar_increment =
> + (uintptr_t)integer_obj[SCALAR_INCR].string.pointer;
> + strncpy_attr(integer_data[instance_id].type, "integer");
> + mutex_unlock(&int_mutex);
> +
> +out:
> + return retval;
> +}
> +
> +/**
> + * exit_int_attributes() - Clear all attribute data
> + * @kset: The kset to free
> + *
> + * Clears all data allocated for this group of attributes
> + **/
> +void exit_int_attributes(struct kset *kset)
> +{
> + struct kobject *pos, *next;
> +
> + mutex_lock(&kset_mutex);
> + list_for_each_entry_safe(pos, next, &kset->list, entry) {
> + sysfs_remove_group(pos, &integer_attr_group);
> + }
> + mutex_unlock(&kset_mutex);
> + mutex_lock(&int_mutex);
> + kfree(integer_data);
> + mutex_unlock(&int_mutex);
> +}
> diff --git a/drivers/platform/x86/dell-wmi-passobj-attributes.c b/drivers/platform/x86/dell-wmi-passobj-attributes.c
> new file mode 100644
> index 000000000000..87bb7772bb18
> --- /dev/null
> +++ b/drivers/platform/x86/dell-wmi-passobj-attributes.c
> @@ -0,0 +1,168 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Functions corresponding to password object type attributes under BIOS Password Object GUID for
> + * use with dell-wmi-sysman
> + *
> + * Copyright (c) 2020 Dell Inc.
> + */
> +
> +#include "dell-wmi-sysman-attributes.h"
> +
> +static DEFINE_MUTEX(po_mutex);
> +extern struct mutex kset_mutex;
> +
> +enum po_properties {IS_PASS_SET = 1, MIN_PASS_LEN, MAX_PASS_LEN};
> +
> +/* kept variable names same as in sysfs file name for sysfs_show macro definition */
> +struct po_data {
> + char attribute_name[MAX_BUFF];
> + int is_password_set;
> + int min_password_length;
> + int max_password_length;
> + char type[MAX_BUFF];
> +};
> +
> +static struct po_data *po_data;
> +static int po_instances_count;
> +get_instance_id(po);
> +
> +static ssize_t is_password_set_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
> +{
> + int instance_id = get_po_instance_id(kobj);
> +
> + if (instance_id >= 0) {
> + union acpi_object *obj;
> +
> + obj = get_wmiobj_pointer(instance_id, DELL_WMI_BIOS_PASSOBJ_ATTRIBUTE_GUID);
> + if (!obj)
> + return -AE_ERROR;
> + po_data[instance_id].is_password_set =
> + (uintptr_t)obj->package.elements[IS_PASS_SET].string.pointer;
> + kfree(obj);
> + return sprintf(buf, "%d\n", po_data[instance_id].is_password_set);
> + }
> + return -EIO;
> +}
> +
> +struct kobj_attribute po_is_pass_set =
> + __ATTR_RO(is_password_set);
> +
> +static ssize_t current_password_store(struct kobject *kobj,
> + struct kobj_attribute *attr,
> + const char *buf, size_t count)
> +{
> + char *p = memchr(buf, '\n', count);
> + int ret;
> +
> + if (p != NULL)
> + *p = '\0';
> + if (strlen(buf) > MAX_BUFF)
> + return -EINVAL;
> +
> + ret = set_current_password(kobj->name, buf);
> + return ret ? ret : count;
> +}
> +
> +struct kobj_attribute po_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)
> +{
> + char *p = memchr(buf, '\n', count);
> + int ret;
> +
> + if (p != NULL)
> + *p = '\0';
> + if (strlen(buf) > MAX_BUFF)
> + return -EINVAL;
> +
> + ret = set_new_password(kobj->name, buf);
> + return ret ? ret : count;
> +}
> +
> +struct kobj_attribute po_new_password =
> + __ATTR_WO(new_password);
> +
> +attribute_n_property_show(min_password_length, po);
> +struct kobj_attribute po_min_pass_length =
> + __ATTR_RO(min_password_length);
> +
> +attribute_n_property_show(max_password_length, po);
> +struct kobj_attribute po_max_pass_length =
> + __ATTR_RO(max_password_length);
> +
> +attribute_s_property_show(type, po);
> +struct kobj_attribute po_type =
> + __ATTR_RO(type);
> +
> +static struct attribute *po_attrs[] = {
> + &po_is_pass_set.attr,
> + &po_min_pass_length.attr,
> + &po_max_pass_length.attr,
> + &po_current_password.attr,
> + &po_new_password.attr,
> + &po_type.attr,
> + NULL,
> +};
> +
> +static const struct attribute_group po_attr_group = {
> + .attrs = po_attrs,
> +};
> +
> +int alloc_po_data(void)
> +{
> + int ret = 0;
> +
> + po_instances_count = get_instance_count(DELL_WMI_BIOS_PASSOBJ_ATTRIBUTE_GUID);
> + po_data = kzalloc((sizeof(struct po_data) * po_instances_count), GFP_KERNEL);
> + if (!po_data)
> + ret = -ENOMEM;
> + return ret;
> +}
> +
> +/**
> + * populate_po_data() - Populate all properties of an instance under password object attribute
> + * @po_obj: ACPI object with password object data
> + * @instance_id: The instance to enumerate
> + * @attr_name_kobj: The parent kernel object
> + **/
> +int populate_po_data(union acpi_object *po_obj, int instance_id, struct kobject *attr_name_kobj)
> +{
> + int retval = sysfs_create_group(attr_name_kobj, &po_attr_group);
> +
> + if (retval)
> + goto out;
> +
> + mutex_lock(&po_mutex);
> + strncpy_attr(po_data[instance_id].attribute_name, po_obj[ATTR_NAME].string.pointer);
> + po_data[instance_id].is_password_set = (uintptr_t)po_obj[IS_PASS_SET].string.pointer;
> + po_data[instance_id].min_password_length = (uintptr_t)po_obj[MIN_PASS_LEN].string.pointer;
> + po_data[instance_id].max_password_length = (uintptr_t) po_obj[MAX_PASS_LEN].string.pointer;
> + strncpy_attr(po_data[instance_id].type, "password_object");
> + mutex_unlock(&po_mutex);
> +
> +out:
> + return retval;
> +}
> +
> +/**
> + * exit_po_attributes() - Clear all attribute data
> + * @kset: The kset to free
> + *
> + * Clears all data allocated for this group of attributes
> + **/
> +void exit_po_attributes(struct kset *kset)
> +{
> + struct kobject *pos, *next;
> +
> + mutex_lock(&kset_mutex);
> + list_for_each_entry_safe(pos, next, &kset->list, entry) {
> + sysfs_remove_group(pos, &po_attr_group);
> + }
> + mutex_unlock(&kset_mutex);
> + mutex_lock(&po_mutex);
> + kfree(po_data);
> + mutex_unlock(&po_mutex);
> +}
> diff --git a/drivers/platform/x86/dell-wmi-passwordattr-interface.c b/drivers/platform/x86/dell-wmi-passwordattr-interface.c
> new file mode 100644
> index 000000000000..d105608cbb86
> --- /dev/null
> +++ b/drivers/platform/x86/dell-wmi-passwordattr-interface.c
> @@ -0,0 +1,200 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Functions corresponding to SET password methods under BIOS attributes interface GUID
> + *
> + * Copyright (c) 2020 Dell Inc.
> + */
> +
> +#include <linux/nls.h>
> +#include <linux/wmi.h>
> +#include "dell-wmi-sysman-attributes.h"
> +
> +static DEFINE_MUTEX(call_mutex);
> +extern struct dell_wmi_sysman_priv wmi_priv;
> +
> +static int call_password_interface(struct wmi_device *wdev, char *in_args, size_t size)
> +{
> + struct acpi_buffer output = {ACPI_ALLOCATE_BUFFER, NULL};
> + struct acpi_buffer input;
> + union acpi_object *obj;
> + acpi_status status;
> + int ret = -EIO;
> +
> + input.length = (acpi_size) size;
> + input.pointer = in_args;
> + status = wmidev_evaluate_method(wdev, 0, 1, &input, &output);
> + if (ACPI_FAILURE(status))
> + return -EIO;
> + obj = (union acpi_object *)output.pointer;
> + if (obj->type == ACPI_TYPE_INTEGER)
> + ret = obj->integer.value;
> +
> + kfree(output.pointer);
> + kobject_uevent(&wdev->dev.kobj, KOBJ_CHANGE);
> + return map_wmi_error(ret);
> +}
> +
> +/**
> + * get_current_password() - Get the current stored password value
> + * @password_type: The type of password to store
> + **/
> +static char *get_current_password(const char *password_type)
> +{
> + if (strcmp(password_type, "Admin") == 0)
> + return wmi_priv.current_admin_password;
> + if (strcmp(password_type, "System") == 0)
> + return wmi_priv.current_system_password;
> + dev_err(&wmi_priv.password_attr_wdev->dev, "unknown password type %s", password_type);
> + return NULL;
> +}
> +
> +/**
> + * set_current_password() - Store current password
> + * @password_type: The type of password to store
> + * @current: The current value
> + *
> + * Sets the current value of the password.
> + * This is used for:
> + * - Resetting password
> + * - Basis for any functions requiring password to execute
> + **/
> +int set_current_password(const char *password_type, const char *cur)
> +{
> + char *current_password = get_current_password(password_type);
> +
> + if (!current_password)
> + return -ENODEV;
> + strncpy(current_password, cur, (strlen(cur) + 1));
> + return 0;
> +}
> +
> +/**
> + * set_new_password() - Sets a system admin password
> + * @password_type: The type of password to set
> + * @new: The new password
> + *
> + * Sets the password using plaintext interface
> + **/
> +int set_new_password(const char *password_type, const char *new)
> +{
> + char *current_password, *type_value, *old_value, *new_value;
> + size_t security_area_size, string_area_size, buffer_size;
> + u8 *type_len, *old_len, *new_len;
> + char *buffer;
> + int ret;
> +
> + /* only allow one password set at a time */
> + mutex_lock(&call_mutex);
> + if (!wmi_priv.password_attr_wdev) {
> + ret = -ENODEV;
> + pr_err("no WMI backend bound");
> + goto out_close_mutex;
> + }
> + current_password = get_current_password(password_type);
> + if (!current_password) {
> + ret = -ENODEV;
> + goto out_close_mutex;
> + }
> +
> + /* build/calculate buffer */
> + security_area_size = calculate_security_buffer();
> + string_area_size = (strlen(password_type) + strlen(current_password) + strlen(new))*2;
> + buffer_size = security_area_size + string_area_size + sizeof(u16) * 3;
> + buffer = kzalloc(buffer_size, GFP_KERNEL);
> + if (!buffer) {
> + ret = -ENOMEM;
> + goto out_close_mutex;
> + }
> +
> + /* build security area */
> + if (strlen(current_password) > 0)
> + populate_security_buffer(buffer, current_password);
> +
> + /* build variables to set */
> + type_len = buffer + security_area_size;
> + type_value = type_len + sizeof(u16);
> + *type_len = utf8s_to_utf16s(password_type, strlen(password_type), UTF16_HOST_ENDIAN,
> + (wchar_t *) type_value, MAX_BUFF) * 2;
> + if (*type_len < 0) {
> + ret = -EINVAL;
> + pr_err("UTF16 conversion failed");
> + goto out_cleanup;
> + }
> +
> + old_len = type_value + *type_len;
> + old_value = old_len + sizeof(u16);
> + *old_len = utf8s_to_utf16s(current_password, strlen(current_password), UTF16_HOST_ENDIAN,
> + (wchar_t *) old_value, MAX_BUFF) * 2;
> + if (*old_len < 0) {
> + ret = -EINVAL;
> + pr_err("UTF16 conversion failed");
> + goto out_cleanup;
> + }
> +
> + new_len = old_value + *old_len;
> + new_value = new_len + sizeof(u16);
> + *new_len = utf8s_to_utf16s(new, strlen(new), UTF16_HOST_ENDIAN,
> + (wchar_t *) new_value, MAX_BUFF) * 2;
> + if (*new_len < 0) {
> + ret = -EINVAL;
> + pr_err("UTF16 conversion failed");
> + goto out_cleanup;
> + }
> +
> + ret = call_password_interface(wmi_priv.password_attr_wdev, buffer, buffer_size);
> + /* update current password so commands work after reset */
> + if (!ret)
> + ret = set_current_password(password_type, new);
> + /* explain to user the detailed failure reason */
> + else if (ret == -EOPNOTSUPP)
> + dev_err(&wmi_priv.password_attr_wdev->dev, "admin password must be configured");
> + else if (ret == -EACCES)
> + dev_err(&wmi_priv.password_attr_wdev->dev, "invalid password");
> +
> +out_cleanup:
> + kfree(buffer);
> +
> +out_close_mutex:
> + mutex_unlock(&call_mutex);
> +
> + return ret;
> +}
> +
> +static int dell_wmi_bios_attr_pass_interface_probe(struct wmi_device *wdev, const void *context)
> +{
> + wmi_priv.password_attr_wdev = wdev;
> + return 0;
> +}
> +
> +static int dell_wmi_bios_attr_pass_interface_remove(struct wmi_device *wdev)
> +{
> + mutex_lock(&call_mutex);
> + wmi_priv.password_attr_wdev = NULL;
> + mutex_unlock(&call_mutex);
> + return 0;
> +}
> +
> +static const struct wmi_device_id dell_wmi_bios_attr_pass_interface_id_table[] = {
> + { .guid_string = DELL_WMI_BIOS_PASSWORD_INTERFACE_GUID },
> + { },
> +};
> +static struct wmi_driver dell_wmi_bios_attr_pass_interface_driver = {
> + .driver = {
> + .name = DRIVER_NAME"-password"
> + },
> + .probe = dell_wmi_bios_attr_pass_interface_probe,
> + .remove = dell_wmi_bios_attr_pass_interface_remove,
> + .id_table = dell_wmi_bios_attr_pass_interface_id_table,
> +};
> +
> +int init_dell_wmi_bios_attr_pass_interface(void)
> +{
> + return wmi_driver_register(&dell_wmi_bios_attr_pass_interface_driver);
> +}
> +
> +void exit_dell_wmi_bios_attr_pass_interface(void)
> +{
> + wmi_driver_unregister(&dell_wmi_bios_attr_pass_interface_driver);
> +}
> +
> +MODULE_DEVICE_TABLE(wmi, dell_wmi_bios_attr_pass_interface_id_table);
> diff --git a/drivers/platform/x86/dell-wmi-string-attributes.c b/drivers/platform/x86/dell-wmi-string-attributes.c
> new file mode 100644
> index 000000000000..397de6fb13a3
> --- /dev/null
> +++ b/drivers/platform/x86/dell-wmi-string-attributes.c
> @@ -0,0 +1,177 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Functions corresponding to string type attributes under BIOS String GUID for use with
> + * dell-wmi-sysman
> + *
> + * Copyright (c) 2020 Dell Inc.
> + */
> +
> +#include "dell-wmi-sysman-attributes.h"
> +
> +static DEFINE_MUTEX(str_mutex);
> +extern struct mutex kset_mutex;
> +
> +enum string_properties {MIN_LEN = 6, MAX_LEN};
> +
> +/* kept variable names same as in sysfs file name for sysfs_show macro definition */
> +struct str_data {
> + char display_name_language_code[MAX_BUFF];
> + char attribute_name[MAX_BUFF];
> + char display_name[MAX_BUFF];
> + char default_value[MAX_BUFF];
> + char current_value[MAX_BUFF];
> + char modifier[MAX_BUFF];
> + int min_length;
> + int max_length;
> + char type[MAX_BUFF];
> +};
> +
> +static struct str_data *str_data;
> +static int str_instances_count;
> +get_instance_id(str);
> +
> +static ssize_t current_value_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
> +{
> + int instance_id;
> +
> + if (!capable(CAP_SYS_ADMIN))
> + return -EPERM;
> + instance_id = get_str_instance_id(kobj);
> + if (instance_id >= 0) {
> + union acpi_object *obj;
> +
> + obj = get_wmiobj_pointer(instance_id, DELL_WMI_BIOS_STRING_ATTRIBUTE_GUID);
> + if (!obj)
> + return -AE_ERROR;
> + strncpy_attr(str_data[instance_id].current_value,
> + obj->package.elements[CURRENT_VAL].string.pointer);
> + kfree(obj);
> + return sprintf(buf, "%s\n", str_data[instance_id].current_value);
> + }
> + return -EIO;
> +}
> +
> +/**
> + * validate_str_input() - Validate input of current_value against min and max lengths
> + * @instance_id: The instance on which input is validated
> + * @buf: Input value
> + **/
> +int validate_str_input(int instance_id, const char *buf)
> +{
> + int in_len = strlen(buf);
> +
> + if ((in_len >= str_data[instance_id].min_length) &&
> + (in_len <= str_data[instance_id].max_length))
> + return 0;
> +
> + return -EINVAL;
> +}
> +
> +attribute_s_property_show(display_name_language_code, str);
> +static struct kobj_attribute str_displ_langcode =
> + __ATTR_RO(display_name_language_code);
> +
> +attribute_s_property_show(display_name, str);
> +struct kobj_attribute str_displ_name =
> + __ATTR_RO(display_name);
> +
> +attribute_s_property_show(default_value, str);
> +struct kobj_attribute str_default_val =
> + __ATTR_RO(default_value);
> +
> +attribute_property_store(current_value, str);
> +struct kobj_attribute str_current_val =
> + __ATTR_RW(current_value);
> +
> +attribute_s_property_show(modifier, str);
> +struct kobj_attribute str_modifier =
> + __ATTR_RO(modifier);
> +
> +attribute_n_property_show(min_length, str);
> +struct kobj_attribute str_min_length =
> + __ATTR_RO(min_length);
> +
> +attribute_n_property_show(max_length, str);
> +struct kobj_attribute str_max_length =
> + __ATTR_RO(max_length);
> +
> +attribute_s_property_show(type, str);
> +struct kobj_attribute str_type =
> + __ATTR_RO(type);
> +
> +static struct attribute *str_attrs[] = {
> + &str_displ_langcode.attr,
> + &str_displ_name.attr,
> + &str_default_val.attr,
> + &str_current_val.attr,
> + &str_modifier.attr,
> + &str_min_length.attr,
> + &str_max_length.attr,
> + &str_type.attr,
> + NULL,
> +};
> +
> +static const struct attribute_group str_attr_group = {
> + .attrs = str_attrs,
> +};
> +
> +int alloc_str_data(void)
> +{
> + int ret = 0;
> +
> + str_instances_count = get_instance_count(DELL_WMI_BIOS_STRING_ATTRIBUTE_GUID);
> + str_data = kzalloc((sizeof(struct str_data) * str_instances_count), GFP_KERNEL);
> + if (!str_data)
> + ret = -ENOMEM;
> + return ret;
> +}
> +
> +/**
> + * populate_enum_data() - Populate all properties of an instance under string attribute
> + * @str_obj: ACPI object with integer data
> + * @instance_id: The instance to enumerate
> + * @attr_name_kobj: The parent kernel object
> + **/
> +int populate_str_data(union acpi_object *str_obj, int instance_id, struct kobject *attr_name_kobj)
> +{
> + int retval = sysfs_create_group(attr_name_kobj, &str_attr_group);
> +
> + if (retval)
> + goto out;
> +
> + mutex_lock(&str_mutex);
> + strncpy_attr(str_data[instance_id].attribute_name, str_obj[ATTR_NAME].string.pointer);
> + strncpy_attr(str_data[instance_id].display_name_language_code,
> + str_obj[DISPL_NAME_LANG_CODE].string.pointer);
> + strncpy_attr(str_data[instance_id].display_name, str_obj[DISPLAY_NAME].string.pointer);
> + strncpy_attr(str_data[instance_id].default_value, str_obj[DEFAULT_VAL].string.pointer);
> + strncpy_attr(str_data[instance_id].current_value, str_obj[CURRENT_VAL].string.pointer);
> + strncpy_attr(str_data[instance_id].modifier, str_obj[MODIFIER].string.pointer);
> + str_data[instance_id].min_length = (uintptr_t)str_obj[MIN_LEN].string.pointer;
> + str_data[instance_id].max_length = (uintptr_t) str_obj[MAX_LEN].string.pointer;
> + strncpy_attr(str_data[instance_id].type, "string");
> + mutex_unlock(&str_mutex);
> +
> +out:
> + return retval;
> +}
> +
> +/**
> + * exit_str_attributes() - Clear all attribute data
> + * @kset: The kset to free
> + *
> + * Clears all data allocated for this group of attributes
> + **/
> +void exit_str_attributes(struct kset *kset)
> +{
> + struct kobject *pos, *next;
> +
> + mutex_lock(&kset_mutex);
> + list_for_each_entry_safe(pos, next, &kset->list, entry) {
> + sysfs_remove_group(pos, &str_attr_group);
> + }
> + mutex_unlock(&kset_mutex);
> + mutex_lock(&str_mutex);
> + kfree(str_data);
> + mutex_unlock(&str_mutex);
> +}
> diff --git a/drivers/platform/x86/dell-wmi-sysman-attributes.c b/drivers/platform/x86/dell-wmi-sysman-attributes.c
> new file mode 100644
> index 000000000000..139d8f5d3d8e
> --- /dev/null
> +++ b/drivers/platform/x86/dell-wmi-sysman-attributes.c
> @@ -0,0 +1,572 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Common methods for use with dell-wmi-sysman
> + *
> + * Copyright (c) 2020 Dell Inc.
> + */
> +
> +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
> +
> +#include <linux/module.h>
> +#include <linux/kernel.h>
> +#include <linux/platform_device.h>
> +#include <linux/dmi.h>
> +#include <linux/wmi.h>
> +#include "dell-wmi-sysman-attributes.h"
> +
> +DEFINE_MUTEX(kset_mutex);
> +
> +#define MAX_TYPES 4
> +
> +static struct platform_device *platform_device;
> +
> +static struct platform_driver platform_driver = {
> + .driver = {
> + .name = DRIVER_NAME,
> + },
> +};
> +
> +/* global structure used by multiple WMI interfaces */
> +struct dell_wmi_sysman_priv wmi_priv;
> +
> +/* attribute directory under platform dev */
> +struct kset *main_dir_kset;
> +
> +/* reset bios to defaults */
> +static const char * const reset_types[] = {"builtinsafe", "lastknowngood", "factory", "custom"};
> +static int reset_option = -1;
> +
> +/**
> + * calculate_security_buffer() - determines size of security buffer for authentication scheme
> + *
> + * Currently only supported type is Admin password
> + **/
> +size_t calculate_security_buffer(void)
> +{
> + if (strlen(wmi_priv.current_admin_password) > 0) {
> + return (sizeof(u32) * 2) +
> + strlen(wmi_priv.current_admin_password) +
> + strlen(wmi_priv.current_admin_password) % 2;
> + }
> + return sizeof(u32) * 2;
> +}
> +
> +/**
> + * populate_security_buffer() - builds a security buffer for authentication scheme
> + * @buffer: the buffer to populate
> + * @authentication: the authentication content
> + *
> + * Currently only supported type is PLAIN TEXT
> + **/
> +void populate_security_buffer(char *buffer, char *authentication)
> +{
> + char *auth = buffer + sizeof(u32)*2;
> + u32 *sectype = (u32 *) buffer;
> + u32 *seclen = sectype + 1;
> + /* plain text */
> + *sectype = 1;
> + *seclen = strlen(authentication);
> + strncpy(auth, authentication, *seclen);
> +}
> +
> +/**
> + * map_wmi_error() - map errors from WMI methods to kernel error codes
> + **/
> +int map_wmi_error(int error_code)
> +{
> + switch (error_code) {
> + case 0:
> + /* success */
> + return 0;
> + case 1:
> + /* failed */
> + return -EIO;
> + case 2:
> + /* invalid parameter */
> + return -EINVAL;
> + case 3:
> + /* access denied */
> + return -EACCES;
> + case 4:
> + /* not supported */
> + return -EOPNOTSUPP;
> + case 5:
> + /* memory error */
> + return -ENOMEM;
> + case 6:
> + /* protocol error */
> + return -EPROTO;
> + }
> + /* unspecified error */
> + return -EIO;
> +}
> +
> +/**
> + * reset_bios_show() - sysfs implementaton for read reset_bios
> + * @kobj: Kernel object for this attribute
> + * @attr: Kernel object attribute
> + * @buf: The buffer to display to userspace
> + **/
> +static ssize_t reset_bios_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
> +{
> + char *start = buf;
> + int i;
> +
> + for (i = 0; i < MAX_TYPES; i++) {
> + if (i == reset_option)
> + buf += sprintf(buf, "[%s] ", reset_types[i]);
> + else
> + buf += sprintf(buf, "%s ", reset_types[i]);
> + }
> + buf += sprintf(buf, "\n");
> + return buf-start;
> +}
> +
> +/**
> + * reset_bios_store() - sysfs implementaton for write reset_bios
> + * @kobj: Kernel object for this attribute
> + * @attr: Kernel object attribute
> + * @buf: The buffer from userspace
> + * @count: the size of the buffer from userspace
> + **/
> +static ssize_t reset_bios_store(struct kobject *kobj,
> + struct kobj_attribute *attr, const char *buf, size_t count)
> +{
> + int len, ret, i;
> + int type = -1;
> + char *p;
> +
> + p = memchr(buf, '\n', count);
> + if (p != NULL)
> + *p = '\0';
> + len = p ? p - buf : count;
> +
> + for (i = 0; i < MAX_TYPES; i++) {
> + if (len == strlen(reset_types[i])
> + && !strncmp(buf, reset_types[i], len)) {
> + type = i;
> + break;
> + }
> + }
> +
> + if (type < 0 || type >= MAX_TYPES) {
> + ret = -EINVAL;
> + goto out;
> + }
> +
> + ret = set_bios_defaults(type);
> + dev_dbg(&platform_device->dev, "reset all attributes request type %d: %d", type, ret);
> + if (ret) {
> + ret = -EINVAL;
> + } else {
> + reset_option = type;
> + ret = count;
> + }
> +
> +out:
> + return ret;
> +}
> +
> +/**
> + * pending_reboot_show() - sysfs implementaton for read pending_reboot
> + * @kobj: Kernel object for this attribute
> + * @attr: Kernel object attribute
> + * @buf: The buffer to display to userspace
> + *
> + * Stores default value as 0
> + * When current_value is changed this attribute is set to 1 to notify reboot may be required
> + **/
> +static ssize_t pending_reboot_show(struct kobject *kobj, struct kobj_attribute *attr,
> + char *buf)
> +{
> + return sprintf(buf, "%d\n", wmi_priv.pending_changes);
> +}
> +
> +static struct kobj_attribute reset_bios = __ATTR_RW(reset_bios);
> +static struct kobj_attribute pending_reboot = __ATTR_RO(pending_reboot);
> +
> +
> +/**
> + * create_reset_bios() - Creates reset_bios and pending_reboot attributes
> + **/
> +static int create_reset_bios(void)
> +{
> + int ret = sysfs_create_file(&main_dir_kset->kobj, &reset_bios.attr);
> +
> + if (ret) {
> + dev_dbg(&platform_device->dev, "could not create reset_bios file");
> + return ret;
> + }
> +
> + ret = sysfs_create_file(&main_dir_kset->kobj, &pending_reboot.attr);
> + if (ret) {
> + dev_dbg(&platform_device->dev, "could not create changing_pending_reboot file");
> + sysfs_remove_file(&main_dir_kset->kobj, &reset_bios.attr);
> + }
> + return ret;
> +}
> +
> +static void release_reset_bios_data(void)
> +{
> + sysfs_remove_file(&main_dir_kset->kobj, &reset_bios.attr);
> + sysfs_remove_file(&main_dir_kset->kobj, &pending_reboot.attr);
> +}
> +
> +static ssize_t kobj_attr_show(struct kobject *kobj, struct attribute *attr,
> + char *buf)
> +{
> + struct kobj_attribute *kattr;
> + ssize_t ret = -EIO;
> +
> + kattr = container_of(attr, struct kobj_attribute, attr);
> + if (kattr->show)
> + ret = kattr->show(kobj, kattr, buf);
> + return ret;
> +}
> +
> +static ssize_t kobj_attr_store(struct kobject *kobj, struct attribute *attr,
> + const char *buf, size_t count)
> +{
> + struct kobj_attribute *kattr;
> + ssize_t ret = -EIO;
> +
> + kattr = container_of(attr, struct kobj_attribute, attr);
> + if (kattr->store)
> + ret = kattr->store(kobj, kattr, buf, count);
> + return ret;
> +}
> +
> +const struct sysfs_ops kobj_sysfs_ops = {
> + .show = kobj_attr_show,
> + .store = kobj_attr_store,
> +};
compile issue (x86_64, make defconfig, make menuconifg selected all pdx86
options built before using git am) after git am building and selecting y for
the new config's defined by this patch:

Intel SCU IPC utility driver (INTEL_SCU_IPC_UTIL) [Y/n/m/?] y
UPD include/config/kernel.release
UPD include/generated/utsrelease.h
CALL scripts/checksyscalls.sh
CALL scripts/atomic/check-atomics.sh
DESCEND objtool
CHK include/generated/compile.h
CC init/version.o
AR init/built-in.a
CC kernel/sys.o
CC kernel/module.o
CC kernel/trace/trace.o
AR kernel/trace/built-in.a
AR kernel/built-in.a
CC drivers/base/firmware_loader/fallback_table.o
CC drivers/base/firmware_loader/main.o
CC drivers/base/firmware_loader/fallback.o
AR drivers/base/firmware_loader/built-in.a
AR drivers/base/built-in.a
CC drivers/platform/x86/dell-wmi-sysman-attributes.o
CC drivers/platform/x86/dell-wmi-enum-attributes.o
CC drivers/platform/x86/dell-wmi-int-attributes.o
CC drivers/platform/x86/dell-wmi-string-attributes.o
CC drivers/platform/x86/dell-wmi-passobj-attributes.o
CC drivers/platform/x86/dell-wmi-passwordattr-interface.o
CC drivers/platform/x86/dell-wmi-biosattr-interface.o
AR drivers/platform/x86/built-in.a
AR drivers/platform/built-in.a
AR drivers/built-in.a
CC net/ethtool/ioctl.o
AR net/ethtool/built-in.a
AR net/built-in.a
GEN .version
CHK include/generated/compile.h
UPD include/generated/compile.h
CC init/version.o
AR init/built-in.a
LD vmlinux.o
drivers/platform/x86/dell-wmi-sysman-attributes.o:(.rodata+0x20): multiple
definition of `kobj_sysfs_ops'
lib/kobject.o:(.rodata+0x40): first defined here
Makefile:1166: recipe for target 'vmlinux' failed
make: *** [vmlinux] Error 1

--mark