diff options
| author | Joshua Grisham <josh@joshuagrisham.com> | 2025-02-22 10:44:07 +0100 |
|---|---|---|
| committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2025-02-25 21:48:51 +0100 |
| commit | 6c00f29f74cb2c063b6f31a0b6d73f9db132b9ac (patch) | |
| tree | dd6d84a6162ca86dda6e2d1db5ca4b2d99fecaad /drivers/acpi/fan_hwmon.c | |
| parent | d082ecbc71e9e0bf49883ee4afd435a77a5101b6 (diff) | |
ACPI: fan: Add fan speed reporting for fans with only _FST
Add support for ACPI fans with _FST to report their speed even if they do
not support fan control.
As suggested by Armin Wolf [1] and per the Windows Thermal Management
Design Guide [2], Samsung Galaxy Book series devices (and possibly many
more devices where the Windows guide was strictly followed) only implement
the _FST method and do not support ACPI-based fan control.
Currently, these fans are not supported by the kernel driver but this patch
will make some very small adjustments to allow them to be supported.
This patch is tested and working for me on a Samsung Galaxy Book2 Pro whose
DSDT (and several other Samsung Galaxy Book series notebooks which
currently have the same issue) can be found at [3].
Link: https://lore.kernel.org/platform-driver-x86/53c5075b-1967-45d0-937f-463912dd966d@gmx.de [1]
Link: https://learn.microsoft.com/en-us/windows-hardware/design/device-experiences/design-guide [2]
Link: https://github.com/joshuagrisham/samsung-galaxybook-extras/tree/8e3087a06b8bdcdfdd081367af4b744a56cc4ee9/dsdt [3]
Signed-off-by: Joshua Grisham <josh@joshuagrisham.com>
Reviewed-by: Armin Wolf <W_Armin@gmx.de>
Link: https://patch.msgid.link/20250222094407.9753-1-josh@joshuagrisham.com
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'drivers/acpi/fan_hwmon.c')
| -rw-r--r-- | drivers/acpi/fan_hwmon.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/drivers/acpi/fan_hwmon.c b/drivers/acpi/fan_hwmon.c index bd0d31a398fa..e8d90605106e 100644 --- a/drivers/acpi/fan_hwmon.c +++ b/drivers/acpi/fan_hwmon.c @@ -43,6 +43,10 @@ static umode_t acpi_fan_hwmon_is_visible(const void *drvdata, enum hwmon_sensor_ case hwmon_fan_input: return 0444; case hwmon_fan_target: + /* Only acpi4 fans support fan control. */ + if (!fan->acpi4) + return 0; + /* * When in fine grain control mode, not every fan control value * has an associated fan performance state. @@ -57,6 +61,10 @@ static umode_t acpi_fan_hwmon_is_visible(const void *drvdata, enum hwmon_sensor_ case hwmon_power: switch (attr) { case hwmon_power_input: + /* Only acpi4 fans support fan control. */ + if (!fan->acpi4) + return 0; + /* * When in fine grain control mode, not every fan control value * has an associated fan performance state. |