diff options
Diffstat (limited to 'drivers/platform/x86/gigabyte-wmi.c')
| -rw-r--r-- | drivers/platform/x86/gigabyte-wmi.c | 164 |
1 files changed, 164 insertions, 0 deletions
diff --git a/drivers/platform/x86/gigabyte-wmi.c b/drivers/platform/x86/gigabyte-wmi.c new file mode 100644 index 0000000000..f6ba88baee --- /dev/null +++ b/drivers/platform/x86/gigabyte-wmi.c @@ -0,0 +1,164 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (C) 2021 Thomas Weißschuh <thomas@weissschuh.net> + */ +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/acpi.h> +#include <linux/hwmon.h> +#include <linux/module.h> +#include <linux/wmi.h> + +#define GIGABYTE_WMI_GUID "DEADBEEF-2001-0000-00A0-C90629100000" +#define NUM_TEMPERATURE_SENSORS 6 + +static u8 usable_sensors_mask; + +enum gigabyte_wmi_commandtype { + GIGABYTE_WMI_BUILD_DATE_QUERY = 0x1, + GIGABYTE_WMI_MAINBOARD_TYPE_QUERY = 0x2, + GIGABYTE_WMI_FIRMWARE_VERSION_QUERY = 0x4, + GIGABYTE_WMI_MAINBOARD_NAME_QUERY = 0x5, + GIGABYTE_WMI_TEMPERATURE_QUERY = 0x125, +}; + +struct gigabyte_wmi_args { + u32 arg1; +}; + +static int gigabyte_wmi_perform_query(struct wmi_device *wdev, + enum gigabyte_wmi_commandtype command, + struct gigabyte_wmi_args *args, struct acpi_buffer *out) +{ + const struct acpi_buffer in = { + .length = sizeof(*args), + .pointer = args, + }; + + acpi_status ret = wmidev_evaluate_method(wdev, 0x0, command, &in, out); + + if (ACPI_FAILURE(ret)) + return -EIO; + + return 0; +} + +static int gigabyte_wmi_query_integer(struct wmi_device *wdev, + enum gigabyte_wmi_commandtype command, + struct gigabyte_wmi_args *args, u64 *res) +{ + union acpi_object *obj; + struct acpi_buffer result = { ACPI_ALLOCATE_BUFFER, NULL }; + int ret; + + ret = gigabyte_wmi_perform_query(wdev, command, args, &result); + if (ret) + return ret; + obj = result.pointer; + if (obj && obj->type == ACPI_TYPE_INTEGER) + *res = obj->integer.value; + else + ret = -EIO; + kfree(result.pointer); + return ret; +} + +static int gigabyte_wmi_temperature(struct wmi_device *wdev, u8 sensor, long *res) +{ + struct gigabyte_wmi_args args = { + .arg1 = sensor, + }; + u64 temp; + acpi_status ret; + + ret = gigabyte_wmi_query_integer(wdev, GIGABYTE_WMI_TEMPERATURE_QUERY, &args, &temp); + if (ret == 0) { + if (temp == 0) + return -ENODEV; + *res = (s8)temp * 1000; // value is a signed 8-bit integer + } + return ret; +} + +static int gigabyte_wmi_hwmon_read(struct device *dev, enum hwmon_sensor_types type, + u32 attr, int channel, long *val) +{ + struct wmi_device *wdev = dev_get_drvdata(dev); + + return gigabyte_wmi_temperature(wdev, channel, val); +} + +static umode_t gigabyte_wmi_hwmon_is_visible(const void *data, enum hwmon_sensor_types type, + u32 attr, int channel) +{ + return usable_sensors_mask & BIT(channel) ? 0444 : 0; +} + +static const struct hwmon_channel_info * const gigabyte_wmi_hwmon_info[] = { + HWMON_CHANNEL_INFO(temp, + HWMON_T_INPUT, + HWMON_T_INPUT, + HWMON_T_INPUT, + HWMON_T_INPUT, + HWMON_T_INPUT, + HWMON_T_INPUT), + NULL +}; + +static const struct hwmon_ops gigabyte_wmi_hwmon_ops = { + .read = gigabyte_wmi_hwmon_read, + .is_visible = gigabyte_wmi_hwmon_is_visible, +}; + +static const struct hwmon_chip_info gigabyte_wmi_hwmon_chip_info = { + .ops = &gigabyte_wmi_hwmon_ops, + .info = gigabyte_wmi_hwmon_info, +}; + +static u8 gigabyte_wmi_detect_sensor_usability(struct wmi_device *wdev) +{ + int i; + long temp; + u8 r = 0; + + for (i = 0; i < NUM_TEMPERATURE_SENSORS; i++) { + if (!gigabyte_wmi_temperature(wdev, i, &temp)) + r |= BIT(i); + } + return r; +} + +static int gigabyte_wmi_probe(struct wmi_device *wdev, const void *context) +{ + struct device *hwmon_dev; + + usable_sensors_mask = gigabyte_wmi_detect_sensor_usability(wdev); + if (!usable_sensors_mask) { + dev_info(&wdev->dev, "No temperature sensors usable"); + return -ENODEV; + } + + hwmon_dev = devm_hwmon_device_register_with_info(&wdev->dev, "gigabyte_wmi", wdev, + &gigabyte_wmi_hwmon_chip_info, NULL); + + return PTR_ERR_OR_ZERO(hwmon_dev); +} + +static const struct wmi_device_id gigabyte_wmi_id_table[] = { + { GIGABYTE_WMI_GUID, NULL }, + { } +}; + +static struct wmi_driver gigabyte_wmi_driver = { + .driver = { + .name = "gigabyte-wmi", + }, + .id_table = gigabyte_wmi_id_table, + .probe = gigabyte_wmi_probe, +}; +module_wmi_driver(gigabyte_wmi_driver); + +MODULE_DEVICE_TABLE(wmi, gigabyte_wmi_id_table); +MODULE_AUTHOR("Thomas Weißschuh <thomas@weissschuh.net>"); +MODULE_DESCRIPTION("Gigabyte WMI temperature driver"); +MODULE_LICENSE("GPL"); |