Hi,
On 4/10/21 5:15 PM, Guenter Roeck wrote:
> On 4/10/21 7:40 AM, Thomas Weißschuh wrote:
>> Changes since v1:
>> * Incorporate feedback from Barnabás Pőcze
>> * Use a WMI driver instead of a platform driver
>> * Let the kernel manage the driver lifecycle
>> * Fix errno/ACPI error confusion
>> * Fix resource cleanup
>> * Document reason for integer casting
>>
>> Changes since v2:
>> * Style cleanups
>> * Test for usability during probing
>> * DMI-based whitelist
>> * CC hwmon maintainers
>>
>> -- >8 --
>>
>> Tested with a X570 I Aorus Pro Wifi.
>> The mainboard contains an ITE IT8688E chip for management.
>> This chips is also handled by drivers/hwmon/i87.c but as it is also used
>> by the firmware itself it needs an ACPI driver.
>>
>> Unfortunately not all sensor registers are handled by the firmware and even
>> less are exposed via WMI.
>>
>> Signed-off-by: Thomas Weißschuh <li...@weissschuh.net>
>> ---
>> MAINTAINERS | 6 +
>> drivers/platform/x86/Kconfig | 11 ++
>> drivers/platform/x86/Makefile | 1 +
>> drivers/platform/x86/gigabyte-wmi.c | 194 ++++++++++++++++++++++++++++
>> 4 files changed, 212 insertions(+)
>> create mode 100644 drivers/platform/x86/gigabyte-wmi.c
>>
>> diff --git a/MAINTAINERS b/MAINTAINERS
>> index d92f85ca831d..9c10cfc00fe8 100644
>> --- a/MAINTAINERS
>> +++ b/MAINTAINERS
>> @@ -7543,6 +7543,12 @@ F: Documentation/filesystems/gfs2*
>> F: fs/gfs2/
>> F: include/uapi/linux/gfs2_ondisk.h
>>
>> +GIGABYTE WMI DRIVER
>> +M: Thomas Weißschuh <li...@weissschuh.net>
>> +L: platform-driver-...@vger.kernel.org
>> +S: Maintained
>> +F: drivers/platform/x86/gigabyte-wmi.c
>> +
>> GNSS SUBSYSTEM
>> M: Johan Hovold <jo...@kernel.org>
>> S: Maintained
>> diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig
>> index ad4e630e73e2..96622a2106f7 100644
>> --- a/drivers/platform/x86/Kconfig
>> +++ b/drivers/platform/x86/Kconfig
>> @@ -123,6 +123,17 @@ config XIAOMI_WMI
>> To compile this driver as a module, choose M here: the module will
>> be called xiaomi-wmi.
>>
>> +config GIGABYTE_WMI
>> + tristate "Gigabyte WMI temperature driver"
>> + depends on ACPI_WMI
>> + depends on HWMON
>> + help
>> + Say Y here if you want to support WMI-based temperature reporting on
>> + Gigabyte mainboards.
>> +
>> + To compile this driver as a module, choose M here: the module will
>> + be called gigabyte-wmi.
>> +
>> config ACERHDF
>> tristate "Acer Aspire One temperature and fan driver"
>> depends on ACPI && THERMAL
>> diff --git a/drivers/platform/x86/Makefile b/drivers/platform/x86/Makefile
>> index 60d554073749..1621ebfd04fd 100644
>> --- a/drivers/platform/x86/Makefile
>> +++ b/drivers/platform/x86/Makefile
>> @@ -15,6 +15,7 @@ obj-$(CONFIG_INTEL_WMI_THUNDERBOLT) +=
>> intel-wmi-thunderbolt.o
>> obj-$(CONFIG_MXM_WMI) += mxm-wmi.o
>> obj-$(CONFIG_PEAQ_WMI) += peaq-wmi.o
>> obj-$(CONFIG_XIAOMI_WMI) += xiaomi-wmi.o
>> +obj-$(CONFIG_GIGABYTE_WMI) += gigabyte-wmi.o
>>
>> # Acer
>> obj-$(CONFIG_ACERHDF) += acerhdf.o
>> diff --git a/drivers/platform/x86/gigabyte-wmi.c
>> b/drivers/platform/x86/gigabyte-wmi.c
>> new file mode 100644
>> index 000000000000..fb4e6d4c1823
>> --- /dev/null
>> +++ b/drivers/platform/x86/gigabyte-wmi.c
>> @@ -0,0 +1,194 @@
>> +// SPDX-License-Identifier: GPL-2.0-or-later
>> +/*
>> + * Copyright (C) 2021 Thomas Weißschuh <tho...@weissschuh.net>
>> + */
>> +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
>> +
>> +#include <linux/acpi.h>
>> +#include <linux/dmi.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
>
> Style: #define<space>name<tab>value
>
> but of course that is Hans' call.
I agree that aligning the 2 define values with tabs would be better.
>
>> +
>> +static bool force_load;
>> +module_param(force_load, bool, 0);
>> +MODULE_PARM_DESC(force_load, "Force loading on non-whitelisted platform");
>> +
>> +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;
>
> That should be checked in gigabyte_wmi_hwmon_is_visible(); that is what that
> function is for.
Good point, actually the way I think this should be done is cache the result of
the initial probe done in gigabyte_wmi_validate_sensor_presence() and use that
in
is_visible to return either 0 (not visible) or 0444, this way you can also
hide sensors when there is a whole in the range of sensors somehow.
So I guess we do need a v4 of this patch after all.
>
>> + *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 0444;
>> +}
>> +
>> +static const struct hwmon_channel_info *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 int gigabyte_wmi_validate_sensor_presence(struct wmi_device *wdev)
>> +{
>> + int working_sensors = 0, i;
>> + long temp;
>> +
>> + for (i = 0; i < NUM_TEMPERATURE_SENSORS; i++) {
>> + if (!gigabyte_wmi_temperature(wdev, i, &temp))
>> + working_sensors++;
>> + }
>> + return working_sensors ? 0 : -ENODEV;
>> +}
>> +
>> +static const struct dmi_system_id gigabyte_wmi_known_working_platforms[] = {
>> + { .matches = {
>> + DMI_EXACT_MATCH(DMI_BOARD_VENDOR, "Gigabyte Technology Co.,
>> Ltd."),
>> + DMI_EXACT_MATCH(DMI_BOARD_NAME, "B550 GAMING X V2"),
>> + }},
>> + { .matches = {
>> + DMI_EXACT_MATCH(DMI_BOARD_VENDOR, "Gigabyte Technology Co.,
>> Ltd."),
>> + DMI_EXACT_MATCH(DMI_BOARD_NAME, "B550M DS3H"),
>> + }},
>> + { .matches = {
>> + DMI_EXACT_MATCH(DMI_BOARD_VENDOR, "Gigabyte Technology Co.,
>> Ltd."),
>> + DMI_EXACT_MATCH(DMI_BOARD_NAME, "Z390 I AORUS PRO WIFI-CF"),
>> + }},
>> + { .matches = {
>> + DMI_EXACT_MATCH(DMI_BOARD_VENDOR, "Gigabyte Technology Co.,
>> Ltd."),
>> + DMI_EXACT_MATCH(DMI_BOARD_NAME, "X570 I AORUS PRO WIFI"),
>> + }},
>> + { }
>> +};
>> +
>> +static int gigabyte_wmi_probe(struct wmi_device *wdev, const void *context)
>> +{
>> + struct device *hwmon_dev;
>> + int ret;
>> +
>> + if (!dmi_check_system(gigabyte_wmi_known_working_platforms)) {
>> + if (force_load)
>> + dev_warn(&wdev->dev, "Forcing loading on
>> non-whitelisted platform");
>> + else
>> + return -ENODEV;
>
> Style:
> if (!force_load)
> return -ENODEV;
> dev_warn(&wdev->dev, "Forcing loading on non-whitelisted
> platform");
Ack, that would be better.
>
>> + }
>> +
>> + ret = gigabyte_wmi_validate_sensor_presence(wdev);
>> + if (ret) {
>> + dev_info(&wdev->dev, "No temperature sensors usable");
>
> Normally one does not display a message if a probe function returns -ENODEV,
> unless it is an error, to avoid polluting the kernel log.
This will normally only be shown when the force_load module parameter is used,
at which point I think it makes sense to explain why the driver is still not
loading.
Regards,
Hans
>
>> + return ret;
>> + }
>> +
>> + 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 <tho...@weissschuh.net>");
>> +MODULE_DESCRIPTION("Gigabyte WMI temperature Driver");
>> +MODULE_LICENSE("GPL");
>>
>> base-commit: 144c79ef33536b4ecb4951e07dbc1f2b7fa99d32
>>
>
