diff options
| author | Daniel Salmun <salmundani@gmail.com> | 2026-09-14 23:11:54 -0300 |
|---|---|---|
| committer | Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> | 2026-10-13 11:44:59 +0300 |
| commit | ee9d80d1cc4a7d76b5bdfab2494a512fca31447e (patch) | |
| tree | 125b3d3766e40e5e8c3325a1ce2ea56ab0b69a24 /include/linux | |
| parent | 0c2c928ea7d33c8131b0785bda4e26a32dce5caa (diff) | |
platform/x86: thinkpad_acpi: Fix fan speed reporting on ThinkPad L440
The L440 (BIOS J4ET93WW) reports its fan as stopped: /proc/acpi/ibm/fan
shows "status: disabled" and "speed: 0", and hwmon fan1_input is 0 under
any load. EC registers 0x2F and 0x84/0x85 always read 0 on this model.
The EC uses the 0x93/0x95 layout handled by TPACPI_FAN_NS. 0x93 reads 4
(FAN_NS_CTRL_STATUS) and 0x95 goes from 255 at idle to about 111 at full
speed. The DSDT has no fan methods.
Add the J4 BIOS family to fan_quirk_table. The fan then reads about
1900 RPM at idle and 2900 RPM under load. The L540 shares the J4 BIOS
and the same EC firmware, so it is covered by the same entry.
Tested on a ThinkPad L440 20ASS20200 with BIOS J4ET93WW and EC J4HT30WW.
Link: https://github.com/lm-sensors/lm-sensors/issues/510
Signed-off-by: Daniel Salmun <salmundani@gmail.com>
Link: https://patch.msgid.link/20260915021154.23252-1-salmundani@gmail.com
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Diffstat (limited to 'include/linux')
0 files changed, 0 insertions, 0 deletions