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authorLinus Torvalds <torvalds@linux-foundation.org>2020-12-16 03:10:17 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2020-12-16 03:10:17 +0300
commit61f914256c56a39a96dc14eae9f394d35b934812 (patch)
treed98d26eed780ccd2285f7508047a53db349e9afc /drivers/platform/x86/dell-wmi-sysman/sysman.c
parent0f97458173a23c8f218f6041767d0a145a13abe6 (diff)
parent0cd3f561efa9adce840140720e0581355db3e554 (diff)
downloadlinux-61f914256c56a39a96dc14eae9f394d35b934812.tar.xz
Merge tag 'platform-drivers-x86-v5.11-1' of git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86
Pull x86 platform driver updates from Hans de Goede: "Highlights: - New driver for changing BIOS settings from within Linux on Dell devices. This introduces a new generic sysfs API for this. Lenovo is working on also supporting this API on their devices - New Intel PMT telemetry and crashlog drivers - Support for SW_TABLET_MODE reporting for the acer-wmi and intel-hid drivers - Preparation work for improving support for Microsoft Surface hardware - Various fixes / improvements / quirks for the panasonic-laptop and others" * tag 'platform-drivers-x86-v5.11-1' of git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86: (81 commits) platform/x86: ISST: Mark mmio_range_devid_0 and mmio_range_devid_1 with static keyword platform/x86: intel-hid: add Rocket Lake ACPI device ID x86/platform: classmate-laptop: add WiFi media button platform/x86: mlx-platform: Fix item counter assignment for MSN2700/ComEx system platform/x86: mlx-platform: Fix item counter assignment for MSN2700, MSN24xx systems tools/power/x86/intel-speed-select: Update version for v5.11 tools/power/x86/intel-speed-select: Account for missing sysfs for die_id tools/power/x86/intel-speed-select: Read TRL from mailbox platform/x86: intel-hid: Do not create SW_TABLET_MODE input-dev when a KIOX010A ACPI dev is present platform/x86: intel-hid: Add alternative method to enable switches platform/x86: intel-hid: Add support for SW_TABLET_MODE platform/x86: intel-vbtn: Fix SW_TABLET_MODE always reporting 1 on some HP x360 models platform/x86: ISST: Change PCI device macros platform/x86: ISST: Allow configurable offset range platform/x86: ISST: Check for unaligned mmio address acer-wireless: send an EV_SYN/SYN_REPORT between state changes platform/x86: dell-wmi-sysman: work around for BIOS bug platform/x86: mlx-platform: remove an unused variable platform/x86: thinkpad_acpi: remove trailing semicolon in macro definition platform/x86: dell-smbios-base: Fix error return code in dell_smbios_init ...
Diffstat (limited to 'drivers/platform/x86/dell-wmi-sysman/sysman.c')
-rw-r--r--drivers/platform/x86/dell-wmi-sysman/sysman.c627
1 files changed, 627 insertions, 0 deletions
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..dc6dd531c996
--- /dev/null
+++ b/drivers/platform/x86/dell-wmi-sysman/sysman.c
@@ -0,0 +1,627 @@
+// 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;
+}
+
+static 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) {
+ retval = -ENOMEM;
+ 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;
+ }
+
+ mutex_unlock(&wmi_priv.mutex);
+ return 0;
+
+err_attr_init:
+ mutex_unlock(&wmi_priv.mutex);
+ release_attributes_data();
+ kfree(obj);
+ 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");