platform/x86: Introduce support for Systems Management Driver over WMI for Dell Systems
authorDivya Bharathi <divya.bharathi@dell.com>
Tue, 27 Oct 2020 13:49:44 +0000 (19:19 +0530)
committerHans de Goede <hdegoede@redhat.com>
Wed, 28 Oct 2020 09:52:16 +0000 (10:52 +0100)
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@redhat.com>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: mark gross <mgross@linux.intel.com>
Co-developed-by: Mario Limonciello <mario.limonciello@dell.com>
Signed-off-by: Mario Limonciello <mario.limonciello@dell.com>
Co-developed-by: Prasanth KSR <prasanth.ksr@dell.com>
Signed-off-by: Prasanth KSR <prasanth.ksr@dell.com>
Signed-off-by: Divya Bharathi <divya.bharathi@dell.com>
Link: https://lore.kernel.org/r/20201027134944.316730-1-divya.bharathi@dell.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
13 files changed:
Documentation/ABI/testing/sysfs-class-firmware-attributes [new file with mode: 0644]
MAINTAINERS
drivers/platform/x86/Kconfig
drivers/platform/x86/Makefile
drivers/platform/x86/dell-wmi-sysman/Makefile [new file with mode: 0644]
drivers/platform/x86/dell-wmi-sysman/biosattr-interface.c [new file with mode: 0644]
drivers/platform/x86/dell-wmi-sysman/dell-wmi-sysman.h [new file with mode: 0644]
drivers/platform/x86/dell-wmi-sysman/enum-attributes.c [new file with mode: 0644]
drivers/platform/x86/dell-wmi-sysman/int-attributes.c [new file with mode: 0644]
drivers/platform/x86/dell-wmi-sysman/passobj-attributes.c [new file with mode: 0644]
drivers/platform/x86/dell-wmi-sysman/passwordattr-interface.c [new file with mode: 0644]
drivers/platform/x86/dell-wmi-sysman/string-attributes.c [new file with mode: 0644]
drivers/platform/x86/dell-wmi-sysman/sysman.c [new file with mode: 0644]

diff --git a/Documentation/ABI/testing/sysfs-class-firmware-attributes b/Documentation/ABI/testing/sysfs-class-firmware-attributes
new file mode 100644 (file)
index 0000000..04a15c7
--- /dev/null
@@ -0,0 +1,224 @@
+What:          /sys/class/firmware-attributes/*/attributes/*/
+Date:          February 2021
+KernelVersion: 5.11
+Contact:       Divya Bharathi <Divya.Bharathi@Dell.com>,
+               Mario Limonciello <mario.limonciello@dell.com>,
+               Prasanth KSR <prasanth.ksr@dell.com>
+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@Dell.com>,
+               Mario Limonciello <mario.limonciello@dell.com>,
+               Prasanth KSR <prasanth.ksr@dell.com>
+
+               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 a 0/1 flag to see if
+                                       <attr> authentication is enabled.
+                                       This attribute is mandatory.
+
+               role:                   The type of authentication used.
+                                       This attribute is mandatory.
+                                       Known types:
+                                               bios-admin: Representing BIOS administrator password
+                                               power-on: Representing a password required to use
+                                                         the system
+
+               mechanism:              The means of authentication.  This attribute is mandatory.
+                                       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@Dell.com>,
+               Mario Limonciello <mario.limonciello@dell.com>,
+               Prasanth KSR <prasanth.ksr@dell.com>
+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@Dell.com>,
+               Mario Limonciello <mario.limonciello@dell.com>,
+               Prasanth KSR <prasanth.ksr@dell.com>
+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.
index 57b0707..38b70bd 100644 (file)
@@ -4991,6 +4991,14 @@ M:       Mario Limonciello <mario.limonciello@dell.com>
 S:     Maintained
 F:     drivers/platform/x86/dell-wmi-descriptor.c
 
+DELL WMI SYSMAN DRIVER
+M:     Divya Bharathi <divya.bharathi@dell.com>
+M:     Mario Limonciello <mario.limonciello@dell.com>
+M:     Prasanth Ksr <prasanth.ksr@dell.com>
+L:     platform-driver-x86@vger.kernel.org
+S:     Maintained
+F:     drivers/platform/x86/dell-wmi-syman/*
+
 DELL WMI NOTIFICATIONS DRIVER
 M:     Matthew Garrett <mjg59@srcf.ucam.org>
 M:     Pali Rohár <pali@kernel.org>
index 6083f82..65fee84 100644 (file)
@@ -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
index aeff497..2643c1c 100644 (file)
@@ -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-$(CONFIG_AMILO_RFKILL)     += amilo-rfkill.o
diff --git a/drivers/platform/x86/dell-wmi-sysman/Makefile b/drivers/platform/x86/dell-wmi-sysman/Makefile
new file mode 100644 (file)
index 0000000..825fb2f
--- /dev/null
@@ -0,0 +1,8 @@
+obj-$(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 (file)
index 0000000..f95d8dd
--- /dev/null
@@ -0,0 +1,186 @@
+// 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, buffer_size;
+       size_t a_name_size, a_value_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);
+       a_name_size = calculate_string_buffer(a_name);
+       a_value_size = calculate_string_buffer(a_value);
+       buffer_size = security_area_size + a_name_size + a_value_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);
+
+       /* build variables to set */
+       start = buffer + security_area_size;
+       ret = populate_string_buffer(start, a_name_size, a_name);
+       if (ret < 0)
+               goto out;
+       start += ret;
+       ret = populate_string_buffer(start, a_value_size, 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 (file)
index 0000000..b80f2a6
--- /dev/null
@@ -0,0 +1,191 @@
+/* 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);                                      \
+       if (!buf_cp)                                                            \
+               return -ENOMEM;                                                 \
+       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_string_buffer(const char *str);
+size_t calculate_security_buffer(char *authentication);
+void populate_security_buffer(char *buffer, char *authentication);
+ssize_t populate_string_buffer(char *buffer, size_t buffer_len, 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 (file)
index 0000000..80f4b77
--- /dev/null
@@ -0,0 +1,189 @@
+// 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)
+{
+       int instance_id = get_enumeration_instance_id(kobj);
+       union acpi_object *obj;
+       ssize_t ret;
+
+       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;
+       if (obj->package.elements[CURRENT_VAL].type != ACPI_TYPE_STRING) {
+               kfree(obj);
+               return -EINVAL;
+       }
+       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_MODE(current_value, 0600);
+
+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 (file)
index 0000000..ea773d8
--- /dev/null
@@ -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)
+{
+       int instance_id = get_integer_instance_id(kobj);
+       union acpi_object *obj;
+       ssize_t ret;
+
+       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;
+       if (obj->package.elements[CURRENT_VAL].type != ACPI_TYPE_INTEGER) {
+               kfree(obj);
+               return -EINVAL;
+       }
+       ret = snprintf(buf, PAGE_SIZE, "%lld\n", obj->package.elements[CURRENT_VAL].integer.value);
+       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_MODE(current_value, 0600);
+
+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 (file)
index 0000000..e6199fb
--- /dev/null
@@ -0,0 +1,194 @@
+// 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)
+{
+       int instance_id = get_po_instance_id(kobj);
+       union acpi_object *obj;
+       ssize_t ret;
+
+       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;
+       if (obj->package.elements[IS_PASS_SET].type != ACPI_TYPE_INTEGER) {
+               kfree(obj);
+               return -EINVAL;
+       }
+       ret = snprintf(buf, PAGE_SIZE, "%lld\n", obj->package.elements[IS_PASS_SET].integer.value);
+       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);
+       if (!buf_cp)
+               return -ENOMEM;
+       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 (file)
index 0000000..5780b4d
--- /dev/null
@@ -0,0 +1,153 @@
+// 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 password_type_size, current_password_size, new_size;
+       size_t security_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);
+       password_type_size = calculate_string_buffer(password_type);
+       current_password_size = calculate_string_buffer(current_password);
+       new_size = calculate_string_buffer(new);
+       buffer_size = security_area_size + password_type_size + current_password_size + new_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);
+
+       /* build variables to set */
+       start = buffer + security_area_size;
+       ret = populate_string_buffer(start, password_type_size, password_type);
+       if (ret < 0)
+               goto out;
+
+       start += ret;
+       ret = populate_string_buffer(start, current_password_size, current_password);
+       if (ret < 0)
+               goto out;
+
+       start += ret;
+       ret = populate_string_buffer(start, new_size, 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)
+               memset(current_password, 0, MAX_BUFF);
+       /* 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 (file)
index 0000000..ac75dce
--- /dev/null
@@ -0,0 +1,159 @@
+// 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)
+{
+       int instance_id = get_str_instance_id(kobj);
+       union acpi_object *obj;
+       ssize_t ret;
+
+       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;
+       if (obj->package.elements[CURRENT_VAL].type != ACPI_TYPE_STRING) {
+               kfree(obj);
+               return -EINVAL;
+       }
+       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_MODE(current_value, 0600);
+
+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 (file)
index 0000000..3842575
--- /dev/null
@@ -0,0 +1,625 @@
+// 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
+ * @buffer: the start of the destination buffer
+ * @buffer_len: length of the destination buffer
+ * @str: the string to insert into buffer
+ */
+ssize_t populate_string_buffer(char *buffer, size_t buffer_len, const char *str)
+{
+       u16 *length = (u16 *)buffer;
+       u16 *target = length + 1;
+       int ret;
+
+       ret = utf8s_to_utf16s(str, strlen(str), UTF16_HOST_ENDIAN,
+                             target, buffer_len - sizeof(u16));
+       if (ret < 0) {
+               dev_err(wmi_priv.class_dev, "UTF16 conversion failed\n");
+               return ret;
+       }
+
+       if ((ret * sizeof(u16)) > U16_MAX) {
+               dev_err(wmi_priv.class_dev, "Error string too long\n");
+               return -ERANGE;
+       }
+
+       *length = ret * sizeof(u16);
+       return sizeof(u16) + *length;
+}
+
+/**
+ * calculate_string_buffer() - determines size of string buffer for use with BIOS communication
+ * @str: the string to calculate based upon
+ *
+ */
+size_t calculate_string_buffer(const char *str)
+{
+       /* u16 length field + one UTF16 char for each input char */
+       return sizeof(u16) + strlen(str) * sizeof(u16);
+}
+
+/**
+ * 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 type = sysfs_match_string(reset_types, buf);
+       int ret;
+
+       if (type < 0)
+               return type;
+
+       ret = set_bios_defaults(type);
+       pr_debug("reset all attributes request type %d: %d\n", type, ret);
+       if (!ret) {
+               reset_option = type;
+               ret = count;
+       }
+
+       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@dell.com>");
+MODULE_AUTHOR("Prasanth Ksr <prasanth.ksr@dell.com>");
+MODULE_AUTHOR("Divya Bharathi <divya.bharathi@dell.com>");
+MODULE_DESCRIPTION("Dell platform setting control interface");
+MODULE_LICENSE("GPL");