platform/x86: think-lmi: Add WMI interface support on Lenovo platforms

For Lenovo platforms that support a WMI interface to the BIOS add
support, using the firmware-attributes class, to allow users to access
and modify various BIOS related settings.

Signed-off-by: Mark Pearson <markpearson@lenovo.com>
Link: https://lore.kernel.org/r/20210530223111.25929-3-markpearson@lenovo.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

1 files changed, 81 insertions, 0 deletions

diff --git a/drivers/platform/x86/think-lmi.h b/drivers/platform/x86/think-lmi.h
new file mode 100644
index 000000000000..6cd5325cc50e
--- /dev/null
+++ b/drivers/platform/x86/think-lmi.h
@@ -0,0 +1,81 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+
+#ifndef _THINK_LMI_H_
+#define _THINK_LMI_H_
+
+#include <linux/types.h>
+
+#define TLMI_SETTINGS_COUNT  256
+#define TLMI_SETTINGS_MAXLEN 512
+#define TLMI_PWD_BUFSIZE     129
+#define TLMI_PWDTYPE_MAXLEN   64
+#define TLMI_ENC_MAXLEN       64
+#define TLMI_LANG_MAXLEN       4
+#define TLMI_PWDTYPE_LEN       4
+/*
+ * Longest string should be in the set command: allow size of BIOS
+ * option and choice
+ */
+#define TLMI_GETSET_MAXLEN (TLMI_SETTINGS_MAXLEN + TLMI_SETTINGS_MAXLEN)
+
+/* Possible error values */
+struct tlmi_err_codes {
+	const char *err_str;
+	int err_code;
+};
+
+enum encoding_option {
+	TLMI_ENCODING_ASCII,
+	TLMI_ENCODING_SCANCODE,
+};
+
+/* password configuration details */
+struct tlmi_pwdcfg {
+	uint32_t password_mode;
+	uint32_t password_state;
+	uint32_t min_length;
+	uint32_t max_length;
+	uint32_t supported_encodings;
+	uint32_t supported_keyboard;
+};
+
+/* password setting details */
+struct tlmi_pwd_setting {
+	struct kobject kobj;
+	bool valid;
+	char display_name[TLMI_PWDTYPE_MAXLEN];
+	char password[TLMI_PWD_BUFSIZE];
+	const char *pwd_type;
+	const char *role;
+	int minlen;
+	int maxlen;
+	enum encoding_option encoding;
+	char kbdlang[TLMI_LANG_MAXLEN];
+};
+
+/* Attribute setting details */
+struct tlmi_attr_setting {
+	struct kobject kobj;
+	int index;
+	char display_name[TLMI_SETTINGS_MAXLEN];
+	char *possible_values;
+};
+
+struct think_lmi {
+	struct wmi_device *wmi_device;
+
+	int settings_count;
+	bool can_set_bios_settings;
+	bool can_get_bios_selections;
+	bool can_set_bios_password;
+	bool can_get_password_settings;
+
+	struct tlmi_attr_setting *setting[TLMI_SETTINGS_COUNT];
+	struct device *class_dev;
+	struct kset *attribute_kset;
+	struct kset *authentication_kset;
+	struct tlmi_pwd_setting *pwd_admin;
+	struct tlmi_pwd_setting *pwd_power;
+};
+
+#endif /* !_THINK_LMI_H_ */