[PATCH v6] Introduce support for Systems Management Driver over WMI for Dell Systems

From: Divya Bharathi
Date: Tue Oct 06 2020 - 04:27:49 EST

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>
Cc: mark gross <mgross@xxxxxxxxxxxxxxx>

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>
---

Changes from v5 to v6:
- Fixed Mutex bug in set_bios_defaults
- Adjust wrapping for enum-attributes.c description
- Adjust wrapping for int-attributes.c comparison
- Make current_password mandatory for mechanism == password
- Move strlen of admin check into populate_security_password
- Use correct device for dev_err calls (bios_attr_wdev)
- Remove type from structs and add type-string directly in show functions
- Remove unneeded macro definition (make function static)
- Make calls to get_*_instance_id error handling match kernel style
- Adjust -AE_ERROR to -EIO
- Adjust validate_integer_input to propagate errors
- Make current_password_store return -EIO for an unknown type
- Don't store current_value, read dynamically every time
- Move kobject_uevents to class_dev
- Update all kernel doc comments with standard termination '*/'
- Correct dereferences in alloc_*_data()
- Make value_modifier and value_modifier_count local
- Remove is_enabled from po
- Fix current_password_store const char* handling
- Propagate error value from get_po_instance_id() in is_enabled_show()
- Adjust validate_str_input
- Cleanups to reset_bios_store to use sysfs_match_string
- Adjust set_bios_defaults
- Rename create_reset_bios
- strlcpy_attr handling
- Check number of kset_unregister calls in error path
- Make teardown order match error order
- Pass password into calculate_security_buffer
- Correct handling of const char * values in macros
- Add new function for populating string buffers
- Switch strncasecmp to strcasecmp
+ This wasn't strictly necessary (the firmware rejected invalid strings)
+ However, by doing it in the kernel we can send a more sensbile error -EINVAL

Changes from v4 to v5:
- Correct Kconfig description to not use "WMI" twice.
- s/is_authentication_set/is_enabled/
- Specify that all attributes are optional and take UTF8
- Change authentication type to "role" and "mechanism"
- Explain what semicolons are
- Adjust whitespace of documentation

Changes from v3 to v4:
- Create a firmware-attributes class and tie ksets to a virtual device in it
- Make modifier and value_modifier "dell only" attributes.
- Correct some errors caught by kernel build bot around missing prototypes
- Remove mutexes from populate_* functions and put in init_dell_bios_attrib_wmi instead
- Move all code into a subdirectory drivers/platform/x86/dell-wmi-sysman and remove dell-wmi-*
prefix on files
- Move all data structures into shared struct
- In alloc functions instead of kzalloc use kcalloc and check that there is no overflow
+ Same check for other alloc_foo-data functions
- populate_*: Move sysfs_create_group to end of the function to prevent race conditions
- Save kernel object into each data instance and only remove that rather than sysfs_remove_group
- Document in sysfs file what causes change uevents to come through
- Only notify with change uevent one time on multiple settings modifications
- Adjust lots of string handling
- Make more objects static
- Various whitespace corrections
- Document map_wmi_error properly
- Bump version to 5.11 (February 2021)

Changes from v2 to v3:
- Fix a possible NULL pointer error in init
- Add missing newlines to all dev_err/dev_dbg/pr_err/pr_debug statements
- Correct updating passwords when both Admin and System password are set
- Correct the WMI driver name
- Correct some namespace clashing when compiled into the kernel (Reported by Mark Gross)
- Correct some comment typos
- Adopt suggestions made by Hans:
+ Use single global mutex
+ Clarify reason for uevents with a comment
+ Remove functions for set and get current password
+ Rename lower_bound to min_value and upper_bound to max_value
+ Rename possible_value to possible_values
+ Remove references to float
+ Build a separate passwords directory again since it behaves differently from the other
attributes
+ Move more calls from pr_err -> dev_err
- Documentation cleanups (see v2 patch feedback)
+ Grouping types
+ Syntax of `modifier` output

Changes 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-class-firmware-attributes | 221 +++++++
MAINTAINERS | 8 +
drivers/platform/x86/Kconfig | 12 +
drivers/platform/x86/Makefile | 1 +
drivers/platform/x86/dell-wmi-sysman/Makefile | 8 +
.../x86/dell-wmi-sysman/biosattr-interface.c | 184 ++++++
.../x86/dell-wmi-sysman/dell-wmi-sysman.h | 188 ++++++
.../x86/dell-wmi-sysman/enum-attributes.c | 188 ++++++
.../x86/dell-wmi-sysman/int-attributes.c | 173 +++++
.../x86/dell-wmi-sysman/passobj-attributes.c | 190 ++++++
.../dell-wmi-sysman/passwordattr-interface.c | 151 +++++
.../x86/dell-wmi-sysman/string-attributes.c | 158 +++++
drivers/platform/x86/dell-wmi-sysman/sysman.c | 617 ++++++++++++++++++
13 files changed, 2099 insertions(+)
create mode 100644 Documentation/ABI/testing/sysfs-class-firmware-attributes
create mode 100644 drivers/platform/x86/dell-wmi-sysman/Makefile
create mode 100644 drivers/platform/x86/dell-wmi-sysman/biosattr-interface.c
create mode 100644 drivers/platform/x86/dell-wmi-sysman/dell-wmi-sysman.h
create mode 100644 drivers/platform/x86/dell-wmi-sysman/enum-attributes.c
create mode 100644 drivers/platform/x86/dell-wmi-sysman/int-attributes.c
create mode 100644 drivers/platform/x86/dell-wmi-sysman/passobj-attributes.c
create mode 100644 drivers/platform/x86/dell-wmi-sysman/passwordattr-interface.c
create mode 100644 drivers/platform/x86/dell-wmi-sysman/string-attributes.c
create mode 100644 drivers/platform/x86/dell-wmi-sysman/sysman.c

diff --git a/Documentation/ABI/testing/sysfs-class-firmware-attributes b/Documentation/ABI/testing/sysfs-class-firmware-attributes
new file mode 100644
index 000000000000..045daa797b4e
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-class-firmware-attributes
@@ -0,0 +1,221 @@
+What: /sys/class/firmware-attributes/*/attributes/*/
+Date: February 2021
+KernelVersion: 5.11
+Contact: Divya Bharathi <Divya.Bharathi@xxxxxxxx>,
+ Mario Limonciello <mario.limonciello@xxxxxxxx>,
+ Prasanth KSR <prasanth.ksr@xxxxxxxx>
+Description:
+ A sysfs interface for systems management software to enable
+ configuration capability on supported systems. This directory
+ exposes interfaces for interacting with configuration options.
+
+ Unless otherwise specified in an attribute description all attributes are optional
+ and will accept UTF-8 input.
+
+ type: A file that can be read to obtain the type of attribute. This attribute is
+ mandatory.
+
+ The following are known types:
+ - enumeration: a set of pre-defined valid values
+ - integer: a range of numerical values
+ - string
+
+ All attribute types support the following values:
+
+ 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>
+
+ This attribute is mandatory.
+
+ 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>
+
+ "enumeration"-type specific properties:
+
+ possible_values: A file that can be read to obtain the possible
+ values of the <attr>. Values are separated using
+ semi-colon (``;``).
+
+ "integer"-type specific properties:
+
+ min_value: A file that can be read to obtain the lower
+ bound value of the <attr>
+
+ max_value: 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 scalar value used for
+ increments of current_value this attribute accepts.
+
+ "string"-type specific properties:
+
+ 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>
+
+ Dell specific class extensions
+ --------------------------
+
+ On Dell systems the following additional attributes are available:
+
+ dell_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/if-not attribute Y is configured.
+
+ modifier rules can be in following format:
+ [ReadOnlyIf:<attribute>=<value>]
+ [ReadOnlyIfNot:<attribute>=<value>]
+ [SuppressIf:<attribute>=<value>]
+ [SuppressIfNot:<attribute>=<value>]
+
+ For example:
+ AutoOnFri/dell_modifier has value,
+ [SuppressIfNot:AutoOn=SelectDays]
+
+ This means AutoOnFri will be suppressed in BIOS setup if AutoOn
+ attribute is not "SelectDays" and its value will not be effective
+ through sysfs until this rule is met.
+
+ Enumeration attributes also support the following:
+
+ dell_value_modifier: A file that can be read to obtain value-level dependency.
+ This file is similar to dell_modifier but here, an
+ attribute's current value will be forcefully changed based
+ dependent attributes value.
+
+ dell_value_modifier rules can be in following format:
+ <value>[ForceIf:<attribute>=<value>]
+ <value>[ForceIfNot:<attribute>=<value>]
+
+ For example,
+ LegacyOrom/dell_value_modifier has value:
+ Disabled[ForceIf:SecureBoot=Enabled]
+ This means LegacyOrom's current value will be forced to
+ "Disabled" in BIOS setup if SecureBoot is Enabled and its
+ value will not be effective through sysfs until this rule is
+ met.
+
+What: /sys/class/firmware-attributes/*/authentication/
+Date: February 2021
+KernelVersion: 5.11
+Contact: Divya Bharathi <Divya.Bharathi@xxxxxxxx>,
+ Mario Limonciello <mario.limonciello@xxxxxxxx>,
+ Prasanth KSR <prasanth.ksr@xxxxxxxx>
+
+ Devices support various authentication mechanisms which can be exposed
+ as a separate configuration object.
+
+ For example a "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.
+
+ Change in any of these two authentication methods will also generate an
+ uevent KOBJ_CHANGE.
+
+ is_enabled: A file that can be read to obtain a0/1 flag to see if <attr>
+ authentication is enabled.
+
+ role: The type of authentication used.
+ Known types:
+ bios-admin: Representing a BIOS administrator password
+ power-on: Representing a password required to use the system
+
+ mechanism: The means of authentication.
+ Only supported type currently is "password".
+
+ 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
+
+ This attribute is mandatory when mechanism == "password".
+
+ new_password: A write only value that when used in tandem with
+ current_password will reset a system or admin password.
+
+ Note, password management is session specific. If Admin password is set,
+ same password must be written into current_password file (required for
+ password-validation) and must be cleared once the session is over.
+ For example:
+ echo "password" > current_password
+ echo "disabled" > TouchScreen/current_value
+ echo "" > current_password
+
+ 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
+ require password validation.
+
+What: /sys/class/firmware-attributes/*/attributes/pending_reboot
+Date: February 2021
+KernelVersion: 5.11
+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. Also, an uevent_KOBJ_CHANGE is
+ generated when it changes to 1.
+
+ 0: All BIOS attributes setting are current
+ 1: A reboot is necessary to get pending BIOS attribute changes
+ applied
+
+ Note, userspace applications need to follow below steps for efficient
+ BIOS management,
+ 1. Check if admin password is set. If yes, follow session method for
+ password management as briefed under authentication section above.
+ 2. Before setting any attribute, check if it has any modifiers
+ or value_modifiers. If yes, incorporate them and then modify
+ attribute.
+
+ Drivers may emit a CHANGE uevent when this value changes and userspace
+ may check it again.
+
+What: /sys/class/firmware-attributes/*/attributes/reset_bios
+Date: February 2021
+KernelVersion: 5.11
+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/class/firmware-attributes/*/device/attributes/reset_bios
+ # cat /sys/class/firmware-attributes/*/device/attributes/reset_bios
+ # builtinsafe lastknowngood [factory] custom
+
+ Note that any changes to this attribute requires a reboot
+ for changes to take effect.
diff --git a/MAINTAINERS b/MAINTAINERS
index cd2aea603e03..3d33cd0da69e 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -4951,6 +4951,14 @@ 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-syman/*
+
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 0d91d136bc3b..7b6e90546b17 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-based Systems management driver"
+ 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..36ce38e80c8f 100644
--- a/drivers/platform/x86/Makefile
+++ b/drivers/platform/x86/Makefile
@@ -47,6 +47,7 @@ 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/

# Fujitsu
obj-$(CONFIG_AMILO_RFKILL) += amilo-rfkill.o
diff --git a/drivers/platform/x86/dell-wmi-sysman/Makefile b/drivers/platform/x86/dell-wmi-sysman/Makefile
new file mode 100644
index 000000000000..825fb2fbeea8
--- /dev/null
+++ b/drivers/platform/x86/dell-wmi-sysman/Makefile
@@ -0,0 +1,8 @@
+obj-$(CONFIG_DELL_WMI_SYSMAN) += dell-wmi-sysman.o
+dell-wmi-sysman-objs := sysman.o \
+ enum-attributes.o \
+ int-attributes.o \
+ string-attributes.o \
+ passobj-attributes.o \
+ biosattr-interface.o \
+ passwordattr-interface.o
diff --git a/drivers/platform/x86/dell-wmi-sysman/biosattr-interface.c b/drivers/platform/x86/dell-wmi-sysman/biosattr-interface.c
new file mode 100644
index 000000000000..61e77b581d71
--- /dev/null
+++ b/drivers/platform/x86/dell-wmi-sysman/biosattr-interface.c
@@ -0,0 +1,184 @@
+// 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/wmi.h>
+#include "dell-wmi-sysman.h"
+
+#define SETDEFAULTVALUES_METHOD_ID 0x02
+#define SETBIOSDEFAULTS_METHOD_ID 0x03
+#define SETATTRIBUTE_METHOD_ID 0x04
+
+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;
+
+ if (wmi_priv.pending_changes == 0) {
+ wmi_priv.pending_changes = 1;
+ /* let userland know it may need to check reboot pending again */
+ kobject_uevent(&wmi_priv.class_dev->kobj, KOBJ_CHANGE);
+ }
+ kfree(output.pointer);
+ 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 *buffer = NULL, *start;
+ int ret;
+
+ mutex_lock(&wmi_priv.mutex);
+ if (!wmi_priv.bios_attr_wdev) {
+ ret = -ENODEV;
+ goto out;
+ }
+
+ /* build/calculate buffer */
+ security_area_size = calculate_security_buffer(wmi_priv.current_admin_password);
+ string_area_size = (strlen(a_name) + strlen(a_value)) * sizeof(u16);
+ buffer_size = security_area_size + string_area_size + sizeof(u16) * 2;
+ buffer = kzalloc(buffer_size, GFP_KERNEL);
+ if (!buffer) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ /* build security area */
+ populate_security_buffer(buffer, wmi_priv.current_admin_password);
+
+ /* build variables to set */
+ start = buffer + security_area_size;
+ ret = populate_string_buffer(start, a_name);
+ if (ret < 0)
+ goto out;
+ start += sizeof(u16) + ret;
+ ret = populate_string_buffer(start, a_value);
+ if (ret < 0)
+ goto out;
+
+ print_hex_dump_bytes("set attribute data: ", DUMP_PREFIX_NONE, buffer, buffer_size);
+ ret = call_biosattributes_interface(wmi_priv.bios_attr_wdev,
+ buffer, buffer_size,
+ SETATTRIBUTE_METHOD_ID);
+ if (ret == -EOPNOTSUPP)
+ dev_err(&wmi_priv.bios_attr_wdev->dev, "admin password must be configured\n");
+ else if (ret == -EACCES)
+ dev_err(&wmi_priv.bios_attr_wdev->dev, "invalid password\n");
+
+out:
+ kfree(buffer);
+ mutex_unlock(&wmi_priv.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);
+ char *buffer = NULL;
+ u8 *defaultType;
+ int ret;
+
+ mutex_lock(&wmi_priv.mutex);
+ if (!wmi_priv.bios_attr_wdev) {
+ ret = -ENODEV;
+ goto out;
+ }
+
+ security_area_size = calculate_security_buffer(wmi_priv.current_admin_password);
+ buffer_size = security_area_size + integer_area_size;
+ buffer = kzalloc(buffer_size, GFP_KERNEL);
+ if (!buffer) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ /* build security area */
+ populate_security_buffer(buffer, wmi_priv.current_admin_password);
+
+ 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\n", ret);
+
+ kfree(buffer);
+out:
+ mutex_unlock(&wmi_priv.mutex);
+ return ret;
+}
+
+static int bios_attr_set_interface_probe(struct wmi_device *wdev, const void *context)
+{
+ mutex_lock(&wmi_priv.mutex);
+ wmi_priv.bios_attr_wdev = wdev;
+ mutex_unlock(&wmi_priv.mutex);
+ return 0;
+}
+
+static int bios_attr_set_interface_remove(struct wmi_device *wdev)
+{
+ mutex_lock(&wmi_priv.mutex);
+ wmi_priv.bios_attr_wdev = NULL;
+ mutex_unlock(&wmi_priv.mutex);
+ return 0;
+}
+
+static const struct wmi_device_id bios_attr_set_interface_id_table[] = {
+ { .guid_string = DELL_WMI_BIOS_ATTRIBUTES_INTERFACE_GUID },
+ { },
+};
+static struct wmi_driver bios_attr_set_interface_driver = {
+ .driver = {
+ .name = DRIVER_NAME
+ },
+ .probe = bios_attr_set_interface_probe,
+ .remove = bios_attr_set_interface_remove,
+ .id_table = bios_attr_set_interface_id_table,
+};
+
+int init_bios_attr_set_interface(void)
+{
+ return wmi_driver_register(&bios_attr_set_interface_driver);
+}
+
+void exit_bios_attr_set_interface(void)
+{
+ wmi_driver_unregister(&bios_attr_set_interface_driver);
+}
+
+MODULE_DEVICE_TABLE(wmi, bios_attr_set_interface_id_table);
diff --git a/drivers/platform/x86/dell-wmi-sysman/dell-wmi-sysman.h b/drivers/platform/x86/dell-wmi-sysman/dell-wmi-sysman.h
new file mode 100644
index 000000000000..21ee63e37e83
--- /dev/null
+++ b/drivers/platform/x86/dell-wmi-sysman/dell-wmi-sysman.h
@@ -0,0 +1,188 @@
+/* SPDX-License-Identifier: GPL-2.0
+ * Definitions for kernel modules using Dell WMI System Management Driver
+ *
+ * Copyright (c) 2020 Dell Inc.
+ */
+
+#ifndef _DELL_WMI_BIOS_ATTR_H_
+#define _DELL_WMI_BIOS_ATTR_H_
+
+#include <linux/wmi.h>
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/capability.h>
+
+#define DRIVER_NAME "dell-wmi-sysman"
+#define MAX_BUFF 512
+
+#define DELL_WMI_BIOS_ENUMERATION_ATTRIBUTE_GUID "F1DDEE52-063C-4784-A11E-8A06684B9BF5"
+#define DELL_WMI_BIOS_INTEGER_ATTRIBUTE_GUID "F1DDEE52-063C-4784-A11E-8A06684B9BFA"
+#define DELL_WMI_BIOS_STRING_ATTRIBUTE_GUID "F1DDEE52-063C-4784-A11E-8A06684B9BF9"
+#define DELL_WMI_BIOS_PASSOBJ_ATTRIBUTE_GUID "0894B8D6-44A6-4719-97D7-6AD24108BFD4"
+#define DELL_WMI_BIOS_ATTRIBUTES_INTERFACE_GUID "F1DDEE52-063C-4784-A11E-8A06684B9BF4"
+#define DELL_WMI_BIOS_PASSWORD_INTERFACE_GUID "70FE8229-D03B-4214-A1C6-1F884B1A892A"
+
+struct enumeration_data {
+ struct kobject *attr_name_kobj;
+ char display_name_language_code[MAX_BUFF];
+ char dell_value_modifier[MAX_BUFF];
+ char possible_values[MAX_BUFF];
+ char attribute_name[MAX_BUFF];
+ char default_value[MAX_BUFF];
+ char dell_modifier[MAX_BUFF];
+ char display_name[MAX_BUFF];
+};
+
+struct integer_data {
+ struct kobject *attr_name_kobj;
+ char display_name_language_code[MAX_BUFF];
+ char attribute_name[MAX_BUFF];
+ char dell_modifier[MAX_BUFF];
+ char display_name[MAX_BUFF];
+ int scalar_increment;
+ int default_value;
+ int min_value;
+ int max_value;
+};
+
+struct str_data {
+ struct kobject *attr_name_kobj;
+ char display_name_language_code[MAX_BUFF];
+ char attribute_name[MAX_BUFF];
+ char display_name[MAX_BUFF];
+ char default_value[MAX_BUFF];
+ char dell_modifier[MAX_BUFF];
+ int min_length;
+ int max_length;
+};
+
+struct po_data {
+ struct kobject *attr_name_kobj;
+ char attribute_name[MAX_BUFF];
+ int min_password_length;
+ int max_password_length;
+};
+
+struct wmi_sysman_priv {
+ char current_admin_password[MAX_BUFF];
+ char current_system_password[MAX_BUFF];
+ struct wmi_device *password_attr_wdev;
+ struct wmi_device *bios_attr_wdev;
+ struct kset *authentication_dir_kset;
+ struct kset *main_dir_kset;
+ struct device *class_dev;
+ struct enumeration_data *enumeration_data;
+ int enumeration_instances_count;
+ struct integer_data *integer_data;
+ int integer_instances_count;
+ struct str_data *str_data;
+ int str_instances_count;
+ struct po_data *po_data;
+ int po_instances_count;
+ bool pending_changes;
+ struct mutex mutex;
+};
+
+/* global structure used by multiple WMI interfaces */
+extern struct wmi_sysman_priv wmi_priv;
+
+enum { ENUM, INT, STR, PO };
+
+enum {
+ ATTR_NAME,
+ DISPL_NAME_LANG_CODE,
+ DISPLAY_NAME,
+ DEFAULT_VAL,
+ CURRENT_VAL,
+ MODIFIER
+};
+
+#define get_instance_id(type) \
+static int get_##type##_instance_id(struct kobject *kobj) \
+{ \
+ int i; \
+ for (i = 0; i <= wmi_priv.type##_instances_count; i++) { \
+ if (!(strcmp(kobj->name, wmi_priv.type##_data[i].attribute_name)))\
+ return i; \
+ } \
+ return -EIO; \
+}
+
+#define attribute_s_property_show(name, type) \
+static ssize_t name##_show(struct kobject *kobj, struct kobj_attribute *attr, \
+ char *buf) \
+{ \
+ int i = get_##type##_instance_id(kobj); \
+ if (i >= 0) \
+ return sprintf(buf, "%s\n", wmi_priv.type##_data[i].name); \
+ return 0; \
+}
+
+#define attribute_n_property_show(name, type) \
+static ssize_t name##_show(struct kobject *kobj, struct kobj_attribute *attr, \
+ char *buf) \
+{ \
+ int i = get_##type##_instance_id(kobj); \
+ if (i >= 0) \
+ return sprintf(buf, "%d\n", wmi_priv.type##_data[i].name); \
+ return 0; \
+}
+
+#define attribute_property_store(curr_val, type) \
+static ssize_t curr_val##_store(struct kobject *kobj, \
+ struct kobj_attribute *attr, \
+ const char *buf, size_t count) \
+{ \
+ char *p, *buf_cp; \
+ int i, ret = -EIO; \
+ buf_cp = kstrdup(buf, GFP_KERNEL); \
+ p = memchr(buf_cp, '\n', count); \
+ \
+ if (p != NULL) \
+ *p = '\0'; \
+ i = get_##type##_instance_id(kobj); \
+ if (i >= 0) \
+ ret = validate_##type##_input(i, buf_cp); \
+ if (!ret) \
+ ret = set_attribute(kobj->name, buf_cp); \
+ kfree(buf_cp); \
+ return ret ? ret : count; \
+}
+
+union acpi_object *get_wmiobj_pointer(int instance_id, const char *guid_string);
+int get_instance_count(const char *guid_string);
+void strlcpy_attr(char *dest, char *src);
+
+int populate_enum_data(union acpi_object *enumeration_obj, int instance_id,
+ struct kobject *attr_name_kobj);
+int alloc_enum_data(void);
+void exit_enum_attributes(void);
+
+int populate_int_data(union acpi_object *integer_obj, int instance_id,
+ struct kobject *attr_name_kobj);
+int alloc_int_data(void);
+void exit_int_attributes(void);
+
+int populate_str_data(union acpi_object *str_obj, int instance_id, struct kobject *attr_name_kobj);
+int alloc_str_data(void);
+void exit_str_attributes(void);
+
+int populate_po_data(union acpi_object *po_obj, int instance_id, struct kobject *attr_name_kobj);
+int alloc_po_data(void);
+void exit_po_attributes(void);
+
+int set_attribute(const char *a_name, const char *a_value);
+int set_bios_defaults(u8 defType);
+
+void exit_bios_attr_set_interface(void);
+int init_bios_attr_set_interface(void);
+int map_wmi_error(int error_code);
+size_t calculate_security_buffer(char *authentication);
+void populate_security_buffer(char *buffer, char *authentication);
+int populate_string_buffer(u8 *start, const char *str);
+int set_new_password(const char *password_type, const char *new);
+int init_bios_attr_pass_interface(void);
+void exit_bios_attr_pass_interface(void);
+
+#endif
diff --git a/drivers/platform/x86/dell-wmi-sysman/enum-attributes.c b/drivers/platform/x86/dell-wmi-sysman/enum-attributes.c
new file mode 100644
index 000000000000..00e2e5138be2
--- /dev/null
+++ b/drivers/platform/x86/dell-wmi-sysman/enum-attributes.c
@@ -0,0 +1,188 @@
+// 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.h"
+
+get_instance_id(enumeration);
+
+static ssize_t current_value_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
+{
+ union acpi_object *obj;
+ int instance_id;
+ ssize_t ret;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+ instance_id = get_enumeration_instance_id(kobj);
+ if (instance_id < 0)
+ return instance_id;
+
+ /* need to use specific instance_id and guid combination to get right data */
+ obj = get_wmiobj_pointer(instance_id, DELL_WMI_BIOS_ENUMERATION_ATTRIBUTE_GUID);
+ if (!obj)
+ return -EIO;
+ ret = snprintf(buf, PAGE_SIZE, "%s\n", obj->package.elements[CURRENT_VAL].string.pointer);
+ kfree(obj);
+ return ret;
+}
+
+/**
+ * validate_enumeration_input() - Validate input of current_value against possible values
+ * @instance_id: The instance on which input is validated
+ * @buf: Input value
+ */
+static int validate_enumeration_input(int instance_id, const char *buf)
+{
+ char *options, *tmp, *p;
+ int ret = -EINVAL;
+
+ options = tmp = kstrdup(wmi_priv.enumeration_data[instance_id].possible_values,
+ GFP_KERNEL);
+ if (!options)
+ return -ENOMEM;
+
+ while ((p = strsep(&options, ";")) != NULL) {
+ if (!*p)
+ continue;
+ if (!strcasecmp(p, buf)) {
+ 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);
+static struct kobj_attribute displ_name =
+ __ATTR_RO(display_name);
+
+attribute_s_property_show(default_value, enumeration);
+static struct kobj_attribute default_val =
+ __ATTR_RO(default_value);
+
+attribute_property_store(current_value, enumeration);
+static struct kobj_attribute current_val =
+ __ATTR_RW(current_value);
+
+attribute_s_property_show(dell_modifier, enumeration);
+static struct kobj_attribute modifier =
+ __ATTR_RO(dell_modifier);
+
+attribute_s_property_show(dell_value_modifier, enumeration);
+static struct kobj_attribute value_modfr =
+ __ATTR_RO(dell_value_modifier);
+
+attribute_s_property_show(possible_values, enumeration);
+static struct kobj_attribute poss_val =
+ __ATTR_RO(possible_values);
+
+static ssize_t type_show(struct kobject *kobj, struct kobj_attribute *attr,
+ char *buf)
+{
+ return sprintf(buf, "enumeration\n");
+}
+static 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;
+
+ wmi_priv.enumeration_instances_count =
+ get_instance_count(DELL_WMI_BIOS_ENUMERATION_ATTRIBUTE_GUID);
+ wmi_priv.enumeration_data = kcalloc(wmi_priv.enumeration_instances_count,
+ sizeof(struct enumeration_data), GFP_KERNEL);
+ if (!wmi_priv.enumeration_data) {
+ wmi_priv.enumeration_instances_count = 0;
+ 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 i, next_obj, value_modifier_count, possible_values_count;
+
+ wmi_priv.enumeration_data[instance_id].attr_name_kobj = attr_name_kobj;
+ strlcpy_attr(wmi_priv.enumeration_data[instance_id].attribute_name,
+ enumeration_obj[ATTR_NAME].string.pointer);
+ strlcpy_attr(wmi_priv.enumeration_data[instance_id].display_name_language_code,
+ enumeration_obj[DISPL_NAME_LANG_CODE].string.pointer);
+ strlcpy_attr(wmi_priv.enumeration_data[instance_id].display_name,
+ enumeration_obj[DISPLAY_NAME].string.pointer);
+ strlcpy_attr(wmi_priv.enumeration_data[instance_id].default_value,
+ enumeration_obj[DEFAULT_VAL].string.pointer);
+ strlcpy_attr(wmi_priv.enumeration_data[instance_id].dell_modifier,
+ enumeration_obj[MODIFIER].string.pointer);
+
+ next_obj = MODIFIER + 1;
+
+ value_modifier_count = (uintptr_t)enumeration_obj[next_obj].string.pointer;
+
+ for (i = 0; i < value_modifier_count; i++) {
+ strcat(wmi_priv.enumeration_data[instance_id].dell_value_modifier,
+ enumeration_obj[++next_obj].string.pointer);
+ strcat(wmi_priv.enumeration_data[instance_id].dell_value_modifier, ";");
+ }
+
+ possible_values_count = (uintptr_t) enumeration_obj[++next_obj].string.pointer;
+
+ for (i = 0; i < possible_values_count; i++) {
+ strcat(wmi_priv.enumeration_data[instance_id].possible_values,
+ enumeration_obj[++next_obj].string.pointer);
+ strcat(wmi_priv.enumeration_data[instance_id].possible_values, ";");
+ }
+
+ return sysfs_create_group(attr_name_kobj, &enumeration_attr_group);
+}
+
+/**
+ * exit_enum_attributes() - Clear all attribute data
+ *
+ * Clears all data allocated for this group of attributes
+ */
+void exit_enum_attributes(void)
+{
+ int instance_id;
+
+ for (instance_id = 0; instance_id < wmi_priv.enumeration_instances_count; instance_id++) {
+ if (wmi_priv.enumeration_data[instance_id].attr_name_kobj)
+ sysfs_remove_group(wmi_priv.enumeration_data[instance_id].attr_name_kobj,
+ &enumeration_attr_group);
+ }
+ kfree(wmi_priv.enumeration_data);
+}
diff --git a/drivers/platform/x86/dell-wmi-sysman/int-attributes.c b/drivers/platform/x86/dell-wmi-sysman/int-attributes.c
new file mode 100644
index 000000000000..666232b3a4cb
--- /dev/null
+++ b/drivers/platform/x86/dell-wmi-sysman/int-attributes.c
@@ -0,0 +1,173 @@
+// 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.h"
+
+enum int_properties {MIN_VALUE = 6, MAX_VALUE, SCALAR_INCR};
+
+get_instance_id(integer);
+
+static ssize_t current_value_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
+{
+ union acpi_object *obj;
+ int instance_id;
+ ssize_t ret;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+ instance_id = get_integer_instance_id(kobj);
+ if (instance_id < 0)
+ return instance_id;
+
+ /* need to use specific instance_id and guid combination to get right data */
+ obj = get_wmiobj_pointer(instance_id, DELL_WMI_BIOS_INTEGER_ATTRIBUTE_GUID);
+ if (!obj)
+ return -EIO;
+ ret = snprintf(buf, PAGE_SIZE, "%ld\n",
+ (uintptr_t)obj->package.elements[CURRENT_VAL].string.pointer);
+ kfree(obj);
+ return ret;
+}
+
+/**
+ * validate_integer_input() - Validate input of current_value against lower and upper bound
+ * @instance_id: The instance on which input is validated
+ * @buf: Input value
+ */
+static int validate_integer_input(int instance_id, const char *buf)
+{
+ int in_val;
+ int ret;
+
+ ret = kstrtoint(buf, 0, &in_val);
+ if (ret)
+ return ret;
+ if (in_val < wmi_priv.integer_data[instance_id].min_value ||
+ in_val > wmi_priv.integer_data[instance_id].max_value)
+ return -EINVAL;
+
+ 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);
+static struct kobj_attribute integer_displ_name =
+ __ATTR_RO(display_name);
+
+attribute_n_property_show(default_value, integer);
+static struct kobj_attribute integer_default_val =
+ __ATTR_RO(default_value);
+
+attribute_property_store(current_value, integer);
+static struct kobj_attribute integer_current_val =
+ __ATTR_RW(current_value);
+
+attribute_s_property_show(dell_modifier, integer);
+static struct kobj_attribute integer_modifier =
+ __ATTR_RO(dell_modifier);
+
+attribute_n_property_show(min_value, integer);
+static struct kobj_attribute integer_lower_bound =
+ __ATTR_RO(min_value);
+
+attribute_n_property_show(max_value, integer);
+static struct kobj_attribute integer_upper_bound =
+ __ATTR_RO(max_value);
+
+attribute_n_property_show(scalar_increment, integer);
+static struct kobj_attribute integer_scalar_increment =
+ __ATTR_RO(scalar_increment);
+
+static ssize_t type_show(struct kobject *kobj, struct kobj_attribute *attr,
+ char *buf)
+{
+ return sprintf(buf, "integer\n");
+}
+static 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;
+
+ wmi_priv.integer_instances_count = get_instance_count(DELL_WMI_BIOS_INTEGER_ATTRIBUTE_GUID);
+ wmi_priv.integer_data = kcalloc(wmi_priv.integer_instances_count,
+ sizeof(struct integer_data), GFP_KERNEL);
+ if (!wmi_priv.integer_data) {
+ wmi_priv.integer_instances_count = 0;
+ ret = -ENOMEM;
+ }
+ return ret;
+}
+
+/**
+ * populate_int_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)
+{
+ wmi_priv.integer_data[instance_id].attr_name_kobj = attr_name_kobj;
+ strlcpy_attr(wmi_priv.integer_data[instance_id].attribute_name,
+ integer_obj[ATTR_NAME].string.pointer);
+ strlcpy_attr(wmi_priv.integer_data[instance_id].display_name_language_code,
+ integer_obj[DISPL_NAME_LANG_CODE].string.pointer);
+ strlcpy_attr(wmi_priv.integer_data[instance_id].display_name,
+ integer_obj[DISPLAY_NAME].string.pointer);
+ wmi_priv.integer_data[instance_id].default_value =
+ (uintptr_t)integer_obj[DEFAULT_VAL].string.pointer;
+ strlcpy_attr(wmi_priv.integer_data[instance_id].dell_modifier,
+ integer_obj[MODIFIER].string.pointer);
+ wmi_priv.integer_data[instance_id].min_value =
+ (uintptr_t)integer_obj[MIN_VALUE].string.pointer;
+ wmi_priv.integer_data[instance_id].max_value =
+ (uintptr_t)integer_obj[MAX_VALUE].string.pointer;
+ wmi_priv.integer_data[instance_id].scalar_increment =
+ (uintptr_t)integer_obj[SCALAR_INCR].string.pointer;
+
+ return sysfs_create_group(attr_name_kobj, &integer_attr_group);
+}
+
+/**
+ * exit_int_attributes() - Clear all attribute data
+ *
+ * Clears all data allocated for this group of attributes
+ */
+void exit_int_attributes(void)
+{
+ int instance_id;
+
+ for (instance_id = 0; instance_id < wmi_priv.integer_instances_count; instance_id++) {
+ if (wmi_priv.integer_data[instance_id].attr_name_kobj)
+ sysfs_remove_group(wmi_priv.integer_data[instance_id].attr_name_kobj,
+ &integer_attr_group);
+ }
+ kfree(wmi_priv.integer_data);
+}
diff --git a/drivers/platform/x86/dell-wmi-sysman/passobj-attributes.c b/drivers/platform/x86/dell-wmi-sysman/passobj-attributes.c
new file mode 100644
index 000000000000..af77470cef50
--- /dev/null
+++ b/drivers/platform/x86/dell-wmi-sysman/passobj-attributes.c
@@ -0,0 +1,190 @@
+// 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.h"
+
+enum po_properties {IS_PASS_SET = 1, MIN_PASS_LEN, MAX_PASS_LEN};
+
+get_instance_id(po);
+
+static ssize_t is_enabled_show(struct kobject *kobj, struct kobj_attribute *attr,
+ char *buf)
+{
+ union acpi_object *obj;
+ ssize_t ret;
+ int instance_id = get_po_instance_id(kobj);
+
+ if (instance_id < 0)
+ return instance_id;
+
+ /* need to use specific instance_id and guid combination to get right data */
+ obj = get_wmiobj_pointer(instance_id, DELL_WMI_BIOS_PASSOBJ_ATTRIBUTE_GUID);
+ if (!obj)
+ return -EIO;
+
+ ret = sprintf(buf, "%ld\n",
+ (uintptr_t)obj->package.elements[IS_PASS_SET].string.pointer);
+ kfree(obj);
+ return ret;
+}
+
+struct kobj_attribute po_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)
+{
+ char *target = NULL;
+ int length;
+
+ length = strlen(buf);
+ if (buf[length-1] == '\n')
+ length--;
+
+ /* firmware does verifiation of min/max password length,
+ * hence only check for not exceeding MAX_BUFF here.
+ */
+ if (length > MAX_BUFF)
+ return -EINVAL;
+
+ if (strcmp(kobj->name, "Admin") == 0)
+ target = wmi_priv.current_admin_password;
+ else if (strcmp(kobj->name, "System") == 0)
+ target = wmi_priv.current_system_password;
+ if (!target)
+ return -EIO;
+ memcpy(target, buf, length);
+ target[length] = '\0';
+
+ return 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, *buf_cp;
+ int ret;
+
+ buf_cp = kstrdup(buf, GFP_KERNEL);
+ p = memchr(buf_cp, '\n', count);
+
+ if (p != NULL)
+ *p = '\0';
+ if (strlen(buf_cp) > MAX_BUFF) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ ret = set_new_password(kobj->name, buf_cp);
+
+out:
+ kfree(buf_cp);
+ 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);
+
+static ssize_t mechanism_show(struct kobject *kobj, struct kobj_attribute *attr,
+ char *buf)
+{
+ return sprintf(buf, "password\n");
+}
+
+struct kobj_attribute po_mechanism =
+ __ATTR_RO(mechanism);
+
+static ssize_t role_show(struct kobject *kobj, struct kobj_attribute *attr,
+ char *buf)
+{
+ if (strcmp(kobj->name, "Admin") == 0)
+ return sprintf(buf, "bios-admin\n");
+ else if (strcmp(kobj->name, "System") == 0)
+ return sprintf(buf, "power-on\n");
+ return -EIO;
+}
+
+struct kobj_attribute po_role =
+ __ATTR_RO(role);
+
+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_role.attr,
+ &po_mechanism.attr,
+ NULL,
+};
+
+static const struct attribute_group po_attr_group = {
+ .attrs = po_attrs,
+};
+
+int alloc_po_data(void)
+{
+ int ret = 0;
+
+ wmi_priv.po_instances_count = get_instance_count(DELL_WMI_BIOS_PASSOBJ_ATTRIBUTE_GUID);
+ wmi_priv.po_data = kcalloc(wmi_priv.po_instances_count, sizeof(struct po_data), GFP_KERNEL);
+ if (!wmi_priv.po_data) {
+ wmi_priv.po_instances_count = 0;
+ 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)
+{
+ wmi_priv.po_data[instance_id].attr_name_kobj = attr_name_kobj;
+ strlcpy_attr(wmi_priv.po_data[instance_id].attribute_name,
+ po_obj[ATTR_NAME].string.pointer);
+ wmi_priv.po_data[instance_id].min_password_length =
+ (uintptr_t)po_obj[MIN_PASS_LEN].string.pointer;
+ wmi_priv.po_data[instance_id].max_password_length =
+ (uintptr_t) po_obj[MAX_PASS_LEN].string.pointer;
+
+ return sysfs_create_group(attr_name_kobj, &po_attr_group);
+}
+
+/**
+ * exit_po_attributes() - Clear all attribute data
+ *
+ * Clears all data allocated for this group of attributes
+ */
+void exit_po_attributes(void)
+{
+ int instance_id;
+
+ for (instance_id = 0; instance_id < wmi_priv.po_instances_count; instance_id++) {
+ if (wmi_priv.po_data[instance_id].attr_name_kobj)
+ sysfs_remove_group(wmi_priv.po_data[instance_id].attr_name_kobj,
+ &po_attr_group);
+ }
+ kfree(wmi_priv.po_data);
+}
diff --git a/drivers/platform/x86/dell-wmi-sysman/passwordattr-interface.c b/drivers/platform/x86/dell-wmi-sysman/passwordattr-interface.c
new file mode 100644
index 000000000000..7bcadc1a43b8
--- /dev/null
+++ b/drivers/platform/x86/dell-wmi-sysman/passwordattr-interface.c
@@ -0,0 +1,151 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Functions corresponding to SET password methods under BIOS attributes interface GUID
+ *
+ * Copyright (c) 2020 Dell Inc.
+ */
+
+#include <linux/wmi.h>
+#include "dell-wmi-sysman.h"
+
+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);
+ /* let userland know it may need to check is_password_set again */
+ kobject_uevent(&wmi_priv.class_dev->kobj, KOBJ_CHANGE);
+ return map_wmi_error(ret);
+}
+
+/**
+ * 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)
+{
+ size_t security_area_size, string_area_size, buffer_size;
+ char *buffer = NULL, *start;
+ char *current_password;
+ int ret;
+
+ mutex_lock(&wmi_priv.mutex);
+ if (!wmi_priv.password_attr_wdev) {
+ ret = -ENODEV;
+ goto out;
+ }
+ if (strcmp(password_type, "Admin") == 0) {
+ current_password = wmi_priv.current_admin_password;
+ } else if (strcmp(password_type, "System") == 0) {
+ current_password = wmi_priv.current_system_password;
+ } else {
+ ret = -EINVAL;
+ dev_err(&wmi_priv.password_attr_wdev->dev, "unknown password type %s\n",
+ password_type);
+ goto out;
+ }
+
+ /* build/calculate buffer */
+ security_area_size = calculate_security_buffer(wmi_priv.current_admin_password);
+ string_area_size = (strlen(password_type) + strlen(current_password)
+ + strlen(new))*sizeof(u16);
+ buffer_size = security_area_size + string_area_size + sizeof(u16)*3;
+ buffer = kzalloc(buffer_size, GFP_KERNEL);
+ if (!buffer) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ /* build security area */
+ populate_security_buffer(buffer, wmi_priv.current_admin_password);
+
+ /* build variables to set */
+ start = buffer + security_area_size;
+ ret = populate_string_buffer(start, password_type);
+ if (ret < 0)
+ goto out;
+
+ start += sizeof(u16) + ret;
+ ret = populate_string_buffer(start, current_password);
+ if (ret < 0)
+ goto out;
+
+ start += sizeof(u16) + ret;
+ ret = populate_string_buffer(start, new);
+ if (ret < 0)
+ goto out;
+
+ print_hex_dump_bytes("set new password data: ", DUMP_PREFIX_NONE, buffer, buffer_size);
+ ret = call_password_interface(wmi_priv.password_attr_wdev, buffer, buffer_size);
+ /* clear current_password here and use user input from wmi_priv.current_password */
+ if (!ret)
+ current_password = "";
+ /* explain to user the detailed failure reason */
+ else if (ret == -EOPNOTSUPP)
+ dev_err(&wmi_priv.password_attr_wdev->dev, "admin password must be configured\n");
+ else if (ret == -EACCES)
+ dev_err(&wmi_priv.password_attr_wdev->dev, "invalid password\n");
+
+out:
+ kfree(buffer);
+ mutex_unlock(&wmi_priv.mutex);
+
+ return ret;
+}
+
+static int bios_attr_pass_interface_probe(struct wmi_device *wdev, const void *context)
+{
+ mutex_lock(&wmi_priv.mutex);
+ wmi_priv.password_attr_wdev = wdev;
+ mutex_unlock(&wmi_priv.mutex);
+ return 0;
+}
+
+static int bios_attr_pass_interface_remove(struct wmi_device *wdev)
+{
+ mutex_lock(&wmi_priv.mutex);
+ wmi_priv.password_attr_wdev = NULL;
+ mutex_unlock(&wmi_priv.mutex);
+ return 0;
+}
+
+static const struct wmi_device_id bios_attr_pass_interface_id_table[] = {
+ { .guid_string = DELL_WMI_BIOS_PASSWORD_INTERFACE_GUID },
+ { },
+};
+static struct wmi_driver bios_attr_pass_interface_driver = {
+ .driver = {
+ .name = DRIVER_NAME"-password"
+ },
+ .probe = bios_attr_pass_interface_probe,
+ .remove = bios_attr_pass_interface_remove,
+ .id_table = bios_attr_pass_interface_id_table,
+};
+
+int init_bios_attr_pass_interface(void)
+{
+ return wmi_driver_register(&bios_attr_pass_interface_driver);
+}
+
+void exit_bios_attr_pass_interface(void)
+{
+ wmi_driver_unregister(&bios_attr_pass_interface_driver);
+}
+
+MODULE_DEVICE_TABLE(wmi, bios_attr_pass_interface_id_table);
diff --git a/drivers/platform/x86/dell-wmi-sysman/string-attributes.c b/drivers/platform/x86/dell-wmi-sysman/string-attributes.c
new file mode 100644
index 000000000000..463b94f505ad
--- /dev/null
+++ b/drivers/platform/x86/dell-wmi-sysman/string-attributes.c
@@ -0,0 +1,158 @@
+// 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.h"
+
+enum string_properties {MIN_LEN = 6, MAX_LEN};
+
+get_instance_id(str);
+
+static ssize_t current_value_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
+{
+ union acpi_object *obj;
+ int instance_id;
+ ssize_t ret;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+ instance_id = get_str_instance_id(kobj);
+ if (instance_id < 0)
+ return -EIO;
+
+ /* need to use specific instance_id and guid combination to get right data */
+ obj = get_wmiobj_pointer(instance_id, DELL_WMI_BIOS_STRING_ATTRIBUTE_GUID);
+ if (!obj)
+ return -EIO;
+ ret = snprintf(buf, PAGE_SIZE, "%s\n", obj->package.elements[CURRENT_VAL].string.pointer);
+ kfree(obj);
+ return ret;
+}
+
+/**
+ * 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
+ */
+static int validate_str_input(int instance_id, const char *buf)
+{
+ int in_len = strlen(buf);
+
+ if ((in_len < wmi_priv.str_data[instance_id].min_length) ||
+ (in_len > wmi_priv.str_data[instance_id].max_length))
+ return -EINVAL;
+
+ return 0;
+}
+
+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);
+static struct kobj_attribute str_displ_name =
+ __ATTR_RO(display_name);
+
+attribute_s_property_show(default_value, str);
+static struct kobj_attribute str_default_val =
+ __ATTR_RO(default_value);
+
+attribute_property_store(current_value, str);
+static struct kobj_attribute str_current_val =
+ __ATTR_RW(current_value);
+
+attribute_s_property_show(dell_modifier, str);
+static struct kobj_attribute str_modifier =
+ __ATTR_RO(dell_modifier);
+
+attribute_n_property_show(min_length, str);
+static struct kobj_attribute str_min_length =
+ __ATTR_RO(min_length);
+
+attribute_n_property_show(max_length, str);
+static struct kobj_attribute str_max_length =
+ __ATTR_RO(max_length);
+
+static ssize_t type_show(struct kobject *kobj, struct kobj_attribute *attr,
+ char *buf)
+{
+ return sprintf(buf, "string\n");
+}
+static 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;
+
+ wmi_priv.str_instances_count = get_instance_count(DELL_WMI_BIOS_STRING_ATTRIBUTE_GUID);
+ wmi_priv.str_data = kcalloc(wmi_priv.str_instances_count,
+ sizeof(struct str_data), GFP_KERNEL);
+ if (!wmi_priv.str_data) {
+ wmi_priv.str_instances_count = 0;
+ ret = -ENOMEM;
+ }
+ return ret;
+}
+
+/**
+ * populate_str_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)
+{
+ wmi_priv.str_data[instance_id].attr_name_kobj = attr_name_kobj;
+ strlcpy_attr(wmi_priv.str_data[instance_id].attribute_name,
+ str_obj[ATTR_NAME].string.pointer);
+ strlcpy_attr(wmi_priv.str_data[instance_id].display_name_language_code,
+ str_obj[DISPL_NAME_LANG_CODE].string.pointer);
+ strlcpy_attr(wmi_priv.str_data[instance_id].display_name,
+ str_obj[DISPLAY_NAME].string.pointer);
+ strlcpy_attr(wmi_priv.str_data[instance_id].default_value,
+ str_obj[DEFAULT_VAL].string.pointer);
+ strlcpy_attr(wmi_priv.str_data[instance_id].dell_modifier,
+ str_obj[MODIFIER].string.pointer);
+ wmi_priv.str_data[instance_id].min_length = (uintptr_t)str_obj[MIN_LEN].string.pointer;
+ wmi_priv.str_data[instance_id].max_length = (uintptr_t) str_obj[MAX_LEN].string.pointer;
+
+ return sysfs_create_group(attr_name_kobj, &str_attr_group);
+}
+
+/**
+ * exit_str_attributes() - Clear all attribute data
+ *
+ * Clears all data allocated for this group of attributes
+ */
+void exit_str_attributes(void)
+{
+ int instance_id;
+
+ for (instance_id = 0; instance_id < wmi_priv.str_instances_count; instance_id++) {
+ if (wmi_priv.str_data[instance_id].attr_name_kobj)
+ sysfs_remove_group(wmi_priv.str_data[instance_id].attr_name_kobj,
+ &str_attr_group);
+ }
+ kfree(wmi_priv.str_data);
+}
diff --git a/drivers/platform/x86/dell-wmi-sysman/sysman.c b/drivers/platform/x86/dell-wmi-sysman/sysman.c
new file mode 100644
index 000000000000..b415021e7bd5
--- /dev/null
+++ b/drivers/platform/x86/dell-wmi-sysman/sysman.c
@@ -0,0 +1,617 @@
+// 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/fs.h>
+#include <linux/dmi.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/wmi.h>
+#include "dell-wmi-sysman.h"
+
+#define MAX_TYPES 4
+#include <linux/nls.h>
+
+static struct class firmware_attributes_class = {
+ .name = "firmware-attributes",
+};
+
+struct wmi_sysman_priv wmi_priv = {
+ .mutex = __MUTEX_INITIALIZER(wmi_priv.mutex),
+};
+
+/* reset bios to defaults */
+static const char * const reset_types[] = {"builtinsafe", "lastknowngood", "factory", "custom"};
+static int reset_option = -1;
+
+
+/**
+ * populate_string_buffer() - populates a string buffer
+ * @start: the start of the buffer
+ * @str: the string to insert into buffer
+ */
+int populate_string_buffer(u8 *start, const char *str)
+{
+ u16 *target = (u16 *)start + 1;
+ int ret;
+
+ ret = utf8s_to_utf16s(str, strlen(str), UTF16_HOST_ENDIAN,
+ target, MAX_BUFF);
+ if (ret < 0) {
+ dev_err(wmi_priv.class_dev, "UTF16 conversion failed\n");
+ return ret;
+ }
+ *start = ret * 2;
+ return *start;
+}
+
+/**
+ * calculate_security_buffer() - determines size of security buffer for authentication scheme
+ * @authentication: the authentication content
+ *
+ * Currently only supported type is Admin password
+ */
+size_t calculate_security_buffer(char *authentication)
+{
+ if (strlen(authentication) > 0) {
+ return (sizeof(u32) * 2) + strlen(authentication) +
+ strlen(authentication) % 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;
+
+ *sectype = strlen(authentication) > 0 ? 1 : 0;
+ *seclen = strlen(authentication);
+
+ /* plain text */
+ if (strlen(authentication) > 0)
+ memcpy(auth, authentication, *seclen);
+}
+
+/**
+ * map_wmi_error() - map errors from WMI methods to kernel error codes
+ * @error_code: integer error code returned from Dell's firmware
+ */
+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 ret;
+ int type = -1;
+ char *p, *buf_cp;
+
+ buf_cp = kstrdup(buf, GFP_KERNEL);
+ p = memchr(buf_cp, '\n', count);
+ if (p != NULL)
+ *p = '\0';
+
+ type = sysfs_match_string(reset_types, buf_cp);
+ if (type < 0) {
+ ret = type;
+ goto out;
+ }
+
+ ret = set_bios_defaults(type);
+ pr_debug("reset all attributes request type %d: %d\n", type, ret);
+ if (!ret) {
+ reset_option = type;
+ ret = count;
+ }
+
+out:
+ kfree(buf_cp);
+ 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_attributes_level_sysfs_files() - Creates reset_bios and
+ * pending_reboot attributes
+ */
+static int create_attributes_level_sysfs_files(void)
+{
+ int ret = sysfs_create_file(&wmi_priv.main_dir_kset->kobj, &reset_bios.attr);
+
+ if (ret) {
+ pr_debug("could not create reset_bios file\n");
+ return ret;
+ }
+
+ ret = sysfs_create_file(&wmi_priv.main_dir_kset->kobj, &pending_reboot.attr);
+ if (ret) {
+ pr_debug("could not create changing_pending_reboot file\n");
+ sysfs_remove_file(&wmi_priv.main_dir_kset->kobj, &reset_bios.attr);
+ }
+ return ret;
+}
+
+static void release_reset_bios_data(void)
+{
+ sysfs_remove_file(&wmi_priv.main_dir_kset->kobj, &reset_bios.attr);
+ sysfs_remove_file(&wmi_priv.main_dir_kset->kobj, &pending_reboot.attr);
+}
+
+static ssize_t wmi_sysman_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 wmi_sysman_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 wmi_sysman_kobj_sysfs_ops = {
+ .show = wmi_sysman_attr_show,
+ .store = wmi_sysman_attr_store,
+};
+
+static void attr_name_release(struct kobject *kobj)
+{
+ kfree(kobj);
+}
+
+static struct kobj_type attr_name_ktype = {
+ .release = attr_name_release,
+ .sysfs_ops = &wmi_sysman_kobj_sysfs_ops,
+};
+
+/**
+ * strlcpy_attr - Copy a length-limited, NULL-terminated string with bound checks
+ * @dest: Where to copy the string to
+ * @src: Where to copy the string from
+ */
+void strlcpy_attr(char *dest, char *src)
+{
+ size_t len = strlen(src) + 1;
+
+ if (len > 1 && len <= MAX_BUFF)
+ strlcpy(dest, src, len);
+
+ /*len can be zero because any property not-applicable to attribute can
+ * be empty so check only for too long buffers and log error
+ */
+ if (len > MAX_BUFF)
+ pr_err("Source string returned from BIOS is out of bound!\n");
+}
+
+/**
+ * get_wmiobj_pointer() - Get Content of WMI block for particular instance
+ * @instance_id: WMI instance ID
+ * @guid_string: WMI GUID (in str form)
+ *
+ * Fetches the content for WMI block (instance_id) under GUID (guid_string)
+ * Caller must kfree the return
+ */
+union acpi_object *get_wmiobj_pointer(int instance_id, const char *guid_string)
+{
+ struct acpi_buffer out = { ACPI_ALLOCATE_BUFFER, NULL };
+ acpi_status status;
+
+ status = wmi_query_block(guid_string, instance_id, &out);
+
+ return ACPI_SUCCESS(status) ? (union acpi_object *)out.pointer : NULL;
+}
+
+/**
+ * get_instance_count() - Compute total number of instances under guid_string
+ * @guid_string: WMI GUID (in string form)
+ */
+int get_instance_count(const char *guid_string)
+{
+ union acpi_object *wmi_obj = NULL;
+ int i = 0;
+
+ do {
+ kfree(wmi_obj);
+ wmi_obj = get_wmiobj_pointer(i, guid_string);
+ i++;
+ } while (wmi_obj);
+
+ return (i-1);
+}
+
+/**
+ * alloc_attributes_data() - Allocate attributes data for a particular type
+ * @attr_type: Attribute type to allocate
+ */
+static int alloc_attributes_data(int attr_type)
+{
+ int retval = 0;
+
+ switch (attr_type) {
+ case ENUM:
+ retval = alloc_enum_data();
+ break;
+ case INT:
+ retval = alloc_int_data();
+ break;
+ case STR:
+ retval = alloc_str_data();
+ break;
+ case PO:
+ retval = alloc_po_data();
+ break;
+ default:
+ break;
+ }
+
+ return retval;
+}
+
+/**
+ * destroy_attribute_objs() - Free a kset of kobjects
+ * @kset: The kset to destroy
+ *
+ * Fress kobjects created for each attribute_name under attribute type kset
+ */
+static void destroy_attribute_objs(struct kset *kset)
+{
+ struct kobject *pos, *next;
+
+ list_for_each_entry_safe(pos, next, &kset->list, entry) {
+ kobject_put(pos);
+ }
+}
+
+/**
+ * release_attributes_data() - Clean-up all sysfs directories and files created
+ */
+static void release_attributes_data(void)
+{
+ release_reset_bios_data();
+
+ mutex_lock(&wmi_priv.mutex);
+ exit_enum_attributes();
+ exit_int_attributes();
+ exit_str_attributes();
+ exit_po_attributes();
+ if (wmi_priv.authentication_dir_kset) {
+ destroy_attribute_objs(wmi_priv.authentication_dir_kset);
+ kset_unregister(wmi_priv.authentication_dir_kset);
+ wmi_priv.authentication_dir_kset = NULL;
+ }
+ if (wmi_priv.main_dir_kset) {
+ destroy_attribute_objs(wmi_priv.main_dir_kset);
+ kset_unregister(wmi_priv.main_dir_kset);
+ }
+ mutex_unlock(&wmi_priv.mutex);
+
+}
+
+/**
+ * init_bios_attributes() - Initialize all attributes for a type
+ * @attr_type: The attribute type to initialize
+ * @guid: The WMI GUID associated with this type to initialize
+ *
+ * Initialiaze all 4 types of attributes enumeration, integer, string and password object.
+ * Populates each attrbute typ's respective properties under sysfs files
+ */
+static int init_bios_attributes(int attr_type, const char *guid)
+{
+ struct kobject *attr_name_kobj; //individual attribute names
+ union acpi_object *obj = NULL;
+ union acpi_object *elements;
+ struct kset *tmp_set;
+
+ /* instance_id needs to be reset for each type GUID
+ * also, instance IDs are unique within GUID but not across
+ */
+ int instance_id = 0;
+ int retval = 0;
+
+ retval = alloc_attributes_data(attr_type);
+ if (retval)
+ return retval;
+ /* need to use specific instance_id and guid combination to get right data */
+ obj = get_wmiobj_pointer(instance_id, guid);
+ if (!obj)
+ return -ENODEV;
+ elements = obj->package.elements;
+
+ mutex_lock(&wmi_priv.mutex);
+ while (elements) {
+ /* sanity checking */
+ if (strlen(elements[ATTR_NAME].string.pointer) == 0) {
+ pr_debug("empty attribute found\n");
+ goto nextobj;
+ }
+ if (attr_type == PO)
+ tmp_set = wmi_priv.authentication_dir_kset;
+ else
+ tmp_set = wmi_priv.main_dir_kset;
+
+ if (kset_find_obj(tmp_set, elements[ATTR_NAME].string.pointer)) {
+ pr_debug("duplicate attribute name found - %s\n",
+ elements[ATTR_NAME].string.pointer);
+ goto nextobj;
+ }
+
+ /* build attribute */
+ attr_name_kobj = kzalloc(sizeof(*attr_name_kobj), GFP_KERNEL);
+ if (!attr_name_kobj)
+ goto err_attr_init;
+
+ attr_name_kobj->kset = tmp_set;
+
+ retval = kobject_init_and_add(attr_name_kobj, &attr_name_ktype, NULL, "%s",
+ elements[ATTR_NAME].string.pointer);
+ if (retval) {
+ kobject_put(attr_name_kobj);
+ goto err_attr_init;
+ }
+
+ /* enumerate all of this attribute */
+ switch (attr_type) {
+ case ENUM:
+ retval = populate_enum_data(elements, instance_id, attr_name_kobj);
+ break;
+ case INT:
+ retval = populate_int_data(elements, instance_id, attr_name_kobj);
+ break;
+ case STR:
+ retval = populate_str_data(elements, instance_id, attr_name_kobj);
+ break;
+ case PO:
+ retval = populate_po_data(elements, instance_id, attr_name_kobj);
+ break;
+ default:
+ break;
+ }
+
+ if (retval) {
+ pr_debug("failed to populate %s\n",
+ elements[ATTR_NAME].string.pointer);
+ goto err_attr_init;
+ }
+
+nextobj:
+ kfree(obj);
+ instance_id++;
+ obj = get_wmiobj_pointer(instance_id, guid);
+ elements = obj ? obj->package.elements : NULL;
+ }
+
+ goto out;
+
+err_attr_init:
+ release_attributes_data();
+ kfree(obj);
+out:
+ mutex_unlock(&wmi_priv.mutex);
+ return retval;
+}
+
+static int __init sysman_init(void)
+{
+ int ret = 0;
+
+ if (!dmi_find_device(DMI_DEV_TYPE_OEM_STRING, "Dell System", NULL) &&
+ !dmi_find_device(DMI_DEV_TYPE_OEM_STRING, "www.dell.com", NULL)) {
+ pr_err("Unable to run on non-Dell system\n");
+ return -ENODEV;
+ }
+
+ ret = init_bios_attr_set_interface();
+ if (ret || !wmi_priv.bios_attr_wdev) {
+ pr_debug("failed to initialize set interface\n");
+ goto fail_set_interface;
+ }
+
+ ret = init_bios_attr_pass_interface();
+ if (ret || !wmi_priv.password_attr_wdev) {
+ pr_debug("failed to initialize pass interface\n");
+ goto fail_pass_interface;
+ }
+
+ ret = class_register(&firmware_attributes_class);
+ if (ret)
+ goto fail_class;
+
+ wmi_priv.class_dev = device_create(&firmware_attributes_class, NULL, MKDEV(0, 0),
+ NULL, "%s", DRIVER_NAME);
+ if (IS_ERR(wmi_priv.class_dev)) {
+ ret = PTR_ERR(wmi_priv.class_dev);
+ goto fail_classdev;
+ }
+
+ wmi_priv.main_dir_kset = kset_create_and_add("attributes", NULL,
+ &wmi_priv.class_dev->kobj);
+ if (!wmi_priv.main_dir_kset) {
+ ret = -ENOMEM;
+ goto fail_main_kset;
+ }
+
+ wmi_priv.authentication_dir_kset = kset_create_and_add("authentication", NULL,
+ &wmi_priv.class_dev->kobj);
+ if (!wmi_priv.authentication_dir_kset) {
+ ret = -ENOMEM;
+ goto fail_authentication_kset;
+ }
+
+ ret = create_attributes_level_sysfs_files();
+ if (ret) {
+ pr_debug("could not create reset BIOS attribute\n");
+ goto fail_reset_bios;
+ }
+
+ ret = init_bios_attributes(ENUM, DELL_WMI_BIOS_ENUMERATION_ATTRIBUTE_GUID);
+ if (ret) {
+ pr_debug("failed to populate enumeration type attributes\n");
+ goto fail_create_group;
+ }
+
+ ret = init_bios_attributes(INT, DELL_WMI_BIOS_INTEGER_ATTRIBUTE_GUID);
+ if (ret) {
+ pr_debug("failed to populate integer type attributes\n");
+ goto fail_create_group;
+ }
+
+ ret = init_bios_attributes(STR, DELL_WMI_BIOS_STRING_ATTRIBUTE_GUID);
+ if (ret) {
+ pr_debug("failed to populate string type attributes\n");
+ goto fail_create_group;
+ }
+
+ ret = init_bios_attributes(PO, DELL_WMI_BIOS_PASSOBJ_ATTRIBUTE_GUID);
+ if (ret) {
+ pr_debug("failed to populate pass object type attributes\n");
+ goto fail_create_group;
+ }
+
+ return 0;
+
+fail_create_group:
+ release_attributes_data();
+
+fail_reset_bios:
+ if (wmi_priv.authentication_dir_kset) {
+ kset_unregister(wmi_priv.authentication_dir_kset);
+ wmi_priv.authentication_dir_kset = NULL;
+ }
+
+fail_authentication_kset:
+ if (wmi_priv.main_dir_kset) {
+ kset_unregister(wmi_priv.main_dir_kset);
+ wmi_priv.main_dir_kset = NULL;
+ }
+
+fail_main_kset:
+ device_destroy(&firmware_attributes_class, MKDEV(0, 0));
+
+fail_classdev:
+ class_unregister(&firmware_attributes_class);
+
+fail_class:
+ exit_bios_attr_pass_interface();
+
+fail_pass_interface:
+ exit_bios_attr_set_interface();
+
+fail_set_interface:
+ return ret;
+}
+
+static void __exit sysman_exit(void)
+{
+ release_attributes_data();
+ device_destroy(&firmware_attributes_class, MKDEV(0, 0));
+ class_unregister(&firmware_attributes_class);
+ exit_bios_attr_set_interface();
+ exit_bios_attr_pass_interface();
+}
+
+module_init(sysman_init);
+module_exit(sysman_exit);
+
+MODULE_AUTHOR("Mario Limonciello <mario.limonciello@xxxxxxxx>");
+MODULE_AUTHOR("Prasanth Ksr <prasanth.ksr@xxxxxxxx>");
+MODULE_AUTHOR("Divya Bharathi <divya.bharathi@xxxxxxxx>");
+MODULE_DESCRIPTION("Dell platform setting control interface");
+MODULE_LICENSE("GPL");
--
2.25.1