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
22static 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
47static DEVICE_ATTR_WO(force_power);
48
49static struct attribute *tbt_attrs[] = {
50	&dev_attr_force_power.attr,
51	NULL
52};
53ATTRIBUTE_GROUPS(tbt);
54
55static const struct wmi_device_id intel_wmi_thunderbolt_id_table[] = {
56	{ .guid_string = INTEL_WMI_THUNDERBOLT_GUID },
57	{ },
58};
59
60static 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
68module_wmi_driver(intel_wmi_thunderbolt_driver);
69
70MODULE_DEVICE_TABLE(wmi, intel_wmi_thunderbolt_id_table);
71MODULE_AUTHOR("Mario Limonciello <mario.limonciello@dell.com>");
72MODULE_DESCRIPTION("Intel WMI Thunderbolt force power driver");
73MODULE_LICENSE("GPL v2");