1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * WMI Thunderbolt driver 4 * 5 * Copyright (C) 2017 Dell Inc. All Rights Reserved. 6 */ 7 8 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 9 10 #include <linux/acpi.h> 11 #include <linux/device.h> 12 #include <linux/fs.h> 13 #include <linux/kernel.h> 14 #include <linux/module.h> 15 #include <linux/string.h> 16 #include <linux/sysfs.h> 17 #include <linux/types.h> 18 #include <linux/wmi.h> 19 20 #define INTEL_WMI_THUNDERBOLT_GUID "86CCFD48-205E-4A77-9C48-2021CBEDE341" 21 22 static ssize_t force_power_store(struct device *dev, 23 struct device_attribute *attr, 24 const char *buf, size_t count) 25 { 26 struct acpi_buffer input; 27 acpi_status status; 28 u8 mode; 29 30 input.length = sizeof(u8); 31 input.pointer = &mode; 32 mode = hex_to_bin(buf[0]); 33 dev_dbg(dev, "force_power: storing %#x\n", mode); 34 if (mode == 0 || mode == 1) { 35 status = wmidev_evaluate_method(to_wmi_device(dev), 0, 1, &input, NULL); 36 if (ACPI_FAILURE(status)) { 37 dev_dbg(dev, "force_power: failed to evaluate ACPI method\n"); 38 return -ENODEV; 39 } 40 } else { 41 dev_dbg(dev, "force_power: unsupported mode\n"); 42 return -EINVAL; 43 } 44 return count; 45 } 46 47 static DEVICE_ATTR_WO(force_power); 48 49 static struct attribute *tbt_attrs[] = { 50 &dev_attr_force_power.attr, 51 NULL 52 }; 53 ATTRIBUTE_GROUPS(tbt); 54 55 static const struct wmi_device_id intel_wmi_thunderbolt_id_table[] = { 56 { .guid_string = INTEL_WMI_THUNDERBOLT_GUID }, 57 { }, 58 }; 59 60 static struct wmi_driver intel_wmi_thunderbolt_driver = { 61 .driver = { 62 .name = "intel-wmi-thunderbolt", 63 .dev_groups = tbt_groups, 64 }, 65 .id_table = intel_wmi_thunderbolt_id_table, 66 }; 67 68 module_wmi_driver(intel_wmi_thunderbolt_driver); 69 70 MODULE_DEVICE_TABLE(wmi, intel_wmi_thunderbolt_id_table); 71 MODULE_AUTHOR("Mario Limonciello <mario.limonciello@dell.com>"); 72 MODULE_DESCRIPTION("Intel WMI Thunderbolt force power driver"); 73 MODULE_LICENSE("GPL v2"); 74