platform/x86: toshiba_acpi: Add fan RPM reading (internals)
This add the internal feature detection and reading function for fan RPM.
The approach is based on tracing ACPI calls using AMLI (a tracer/debugger
built into ACPI.sys) while using the Windows cooling self-test software.
The call used is {HCI_GET, 0x45, 0, 1, 0, 0} which returns:
{0x0, 0x45, fan_rpm, probably_max_rpm, 0x0, 0x0}
What is probably the max RPM is not currently used.
Signed-off-by: Arvid Norlander <lkml@vorpal.se>
Link: https://lore.kernel.org/r/20220902174018.1720029-2-lkml@vorpal.se
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>