1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * Copyright (C) 2021 Thomas Weißschuh <thomas@weissschuh.net> |
4 | */ |
5 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
6 | |
7 | #include <linux/acpi.h> |
8 | #include <linux/hwmon.h> |
9 | #include <linux/module.h> |
10 | #include <linux/wmi.h> |
11 | |
12 | #define GIGABYTE_WMI_GUID "DEADBEEF-2001-0000-00A0-C90629100000" |
13 | #define NUM_TEMPERATURE_SENSORS 6 |
14 | |
15 | static u8 usable_sensors_mask; |
16 | |
17 | enum gigabyte_wmi_commandtype { |
18 | GIGABYTE_WMI_BUILD_DATE_QUERY = 0x1, |
19 | GIGABYTE_WMI_MAINBOARD_TYPE_QUERY = 0x2, |
20 | GIGABYTE_WMI_FIRMWARE_VERSION_QUERY = 0x4, |
21 | GIGABYTE_WMI_MAINBOARD_NAME_QUERY = 0x5, |
22 | GIGABYTE_WMI_TEMPERATURE_QUERY = 0x125, |
23 | }; |
24 | |
25 | struct gigabyte_wmi_args { |
26 | u32 arg1; |
27 | }; |
28 | |
29 | static int gigabyte_wmi_perform_query(struct wmi_device *wdev, |
30 | enum gigabyte_wmi_commandtype command, |
31 | struct gigabyte_wmi_args *args, struct acpi_buffer *out) |
32 | { |
33 | const struct acpi_buffer in = { |
34 | .length = sizeof(*args), |
35 | .pointer = args, |
36 | }; |
37 | |
38 | acpi_status ret = wmidev_evaluate_method(wdev, instance: 0x0, method_id: command, in: &in, out); |
39 | |
40 | if (ACPI_FAILURE(ret)) |
41 | return -EIO; |
42 | |
43 | return 0; |
44 | } |
45 | |
46 | static int gigabyte_wmi_query_integer(struct wmi_device *wdev, |
47 | enum gigabyte_wmi_commandtype command, |
48 | struct gigabyte_wmi_args *args, u64 *res) |
49 | { |
50 | union acpi_object *obj; |
51 | struct acpi_buffer result = { ACPI_ALLOCATE_BUFFER, NULL }; |
52 | int ret; |
53 | |
54 | ret = gigabyte_wmi_perform_query(wdev, command, args, out: &result); |
55 | if (ret) |
56 | return ret; |
57 | obj = result.pointer; |
58 | if (obj && obj->type == ACPI_TYPE_INTEGER) |
59 | *res = obj->integer.value; |
60 | else |
61 | ret = -EIO; |
62 | kfree(objp: result.pointer); |
63 | return ret; |
64 | } |
65 | |
66 | static int gigabyte_wmi_temperature(struct wmi_device *wdev, u8 sensor, long *res) |
67 | { |
68 | struct gigabyte_wmi_args args = { |
69 | .arg1 = sensor, |
70 | }; |
71 | u64 temp; |
72 | acpi_status ret; |
73 | |
74 | ret = gigabyte_wmi_query_integer(wdev, command: GIGABYTE_WMI_TEMPERATURE_QUERY, args: &args, res: &temp); |
75 | if (ret == 0) { |
76 | if (temp == 0) |
77 | return -ENODEV; |
78 | *res = (s8)temp * 1000; // value is a signed 8-bit integer |
79 | } |
80 | return ret; |
81 | } |
82 | |
83 | static int gigabyte_wmi_hwmon_read(struct device *dev, enum hwmon_sensor_types type, |
84 | u32 attr, int channel, long *val) |
85 | { |
86 | struct wmi_device *wdev = dev_get_drvdata(dev); |
87 | |
88 | return gigabyte_wmi_temperature(wdev, sensor: channel, res: val); |
89 | } |
90 | |
91 | static umode_t gigabyte_wmi_hwmon_is_visible(const void *data, enum hwmon_sensor_types type, |
92 | u32 attr, int channel) |
93 | { |
94 | return usable_sensors_mask & BIT(channel) ? 0444 : 0; |
95 | } |
96 | |
97 | static const struct hwmon_channel_info * const gigabyte_wmi_hwmon_info[] = { |
98 | HWMON_CHANNEL_INFO(temp, |
99 | HWMON_T_INPUT, |
100 | HWMON_T_INPUT, |
101 | HWMON_T_INPUT, |
102 | HWMON_T_INPUT, |
103 | HWMON_T_INPUT, |
104 | HWMON_T_INPUT), |
105 | NULL |
106 | }; |
107 | |
108 | static const struct hwmon_ops gigabyte_wmi_hwmon_ops = { |
109 | .read = gigabyte_wmi_hwmon_read, |
110 | .is_visible = gigabyte_wmi_hwmon_is_visible, |
111 | }; |
112 | |
113 | static const struct hwmon_chip_info gigabyte_wmi_hwmon_chip_info = { |
114 | .ops = &gigabyte_wmi_hwmon_ops, |
115 | .info = gigabyte_wmi_hwmon_info, |
116 | }; |
117 | |
118 | static u8 gigabyte_wmi_detect_sensor_usability(struct wmi_device *wdev) |
119 | { |
120 | int i; |
121 | long temp; |
122 | u8 r = 0; |
123 | |
124 | for (i = 0; i < NUM_TEMPERATURE_SENSORS; i++) { |
125 | if (!gigabyte_wmi_temperature(wdev, sensor: i, res: &temp)) |
126 | r |= BIT(i); |
127 | } |
128 | return r; |
129 | } |
130 | |
131 | static int gigabyte_wmi_probe(struct wmi_device *wdev, const void *context) |
132 | { |
133 | struct device *hwmon_dev; |
134 | |
135 | usable_sensors_mask = gigabyte_wmi_detect_sensor_usability(wdev); |
136 | if (!usable_sensors_mask) { |
137 | dev_info(&wdev->dev, "No temperature sensors usable" ); |
138 | return -ENODEV; |
139 | } |
140 | |
141 | hwmon_dev = devm_hwmon_device_register_with_info(dev: &wdev->dev, name: "gigabyte_wmi" , drvdata: wdev, |
142 | info: &gigabyte_wmi_hwmon_chip_info, NULL); |
143 | |
144 | return PTR_ERR_OR_ZERO(ptr: hwmon_dev); |
145 | } |
146 | |
147 | static const struct wmi_device_id gigabyte_wmi_id_table[] = { |
148 | { GIGABYTE_WMI_GUID, NULL }, |
149 | { } |
150 | }; |
151 | |
152 | static struct wmi_driver gigabyte_wmi_driver = { |
153 | .driver = { |
154 | .name = "gigabyte-wmi" , |
155 | }, |
156 | .id_table = gigabyte_wmi_id_table, |
157 | .probe = gigabyte_wmi_probe, |
158 | }; |
159 | module_wmi_driver(gigabyte_wmi_driver); |
160 | |
161 | MODULE_DEVICE_TABLE(wmi, gigabyte_wmi_id_table); |
162 | MODULE_AUTHOR("Thomas Weißschuh <thomas@weissschuh.net>" ); |
163 | MODULE_DESCRIPTION("Gigabyte WMI temperature driver" ); |
164 | MODULE_LICENSE("GPL" ); |
165 | |