platform/x86: think-lmi: Enable opcode support on BIOS settings

Whilst reviewing some documentation from the FW team on using WMI on
Lenovo system I noticed that we weren't using Opcode support when
changing BIOS settings in the thinkLMI driver.

We should be doing this to ensure we're future proof as the old
non-opcode mechanism has been deprecated.

Tested on X1 Carbon G10 and G11.
Signed-off-by: Mark Pearson <mpearson-lenovo@squebb.ca>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20230601200552.4396-2-mpearson-lenovo@squebb.caSigned-off-by: Hans de Goede <hdegoede@redhat.com>

drivers/platform/x86/think-lmi.c

@@ -1010,7 +1010,33 @@ static ssize_t current_value_store(struct kobject *kobj,
 				tlmi_priv.pwd_admin->save_signature);
 		if (ret)
 			goto out;
-	} else { /* Non certiifcate based authentication */
+	} else if (tlmi_priv.opcode_support) {
+		/*
+		 * If opcode support is present use that interface.
+		 * Note - this sets the variable and then the password as separate
+		 * WMI calls. Function tlmi_save_bios_settings will error if the
+		 * password is incorrect.
+		 */
+		set_str = kasprintf(GFP_KERNEL, "%s,%s;", setting->display_name,
+				    new_setting);
+		if (!set_str) {
+			ret = -ENOMEM;
+			goto out;
+		}
+
+		ret = tlmi_simple_call(LENOVO_SET_BIOS_SETTINGS_GUID, set_str);
+		if (ret)
+			goto out;
+
+		if (tlmi_priv.pwd_admin->valid && tlmi_priv.pwd_admin->password[0]) {
+			ret = tlmi_opcode_setting("WmiOpcodePasswordAdmin",
+						  tlmi_priv.pwd_admin->password);
+			if (ret)
+				goto out;
+		}
+
+		ret = tlmi_save_bios_settings("");
+	} else { /* old non-opcode based authentication method (deprecated) */
 		if (tlmi_priv.pwd_admin->valid && tlmi_priv.pwd_admin->password[0]) {
 			auth_str = kasprintf(GFP_KERNEL, "%s,%s,%s;",
 					tlmi_priv.pwd_admin->password,