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
force_power_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)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 .no_singleton = true,
67 };
68
69 module_wmi_driver(intel_wmi_thunderbolt_driver);
70
71 MODULE_DEVICE_TABLE(wmi, intel_wmi_thunderbolt_id_table);
72 MODULE_AUTHOR("Mario Limonciello <mario.limonciello@dell.com>");
73 MODULE_DESCRIPTION("Intel WMI Thunderbolt force power driver");
74 MODULE_LICENSE("GPL v2");
75