Re: [Patch 1/2] ACPI: thermal: Add Thermal fast Sampling Period (_TFP) support

From: Rafael J. Wysocki
Date: Fri Aug 18 2023 - 14:35:06 EST


On Thu, Aug 17, 2023 at 11:30 AM Sumit Gupta <sumitg@xxxxxxxxxx> wrote:
>
> From: Jeff Brasen <jbrasen@xxxxxxxxxx>
>
> Add support for Thermal fast Sampling Period (_TFP) for Passive cooling.
> As per UEFI spec,

You mean the ACPI spec I suppose? It would be good to give the
relevant section number and title.

> _TFP overrides the "Thermal Sampling Period (_TSP)"
> if both are present in a Thermal zone.
>
> Signed-off-by: Jeff Brasen <jbrasen@xxxxxxxxxx>
> Signed-off-by: Sumit Gupta <sumitg@xxxxxxxxxx>
> ---
> drivers/acpi/thermal.c | 21 ++++++++++++++-------
> 1 file changed, 14 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/acpi/thermal.c b/drivers/acpi/thermal.c
> index f9f6ebb08fdb..5dee3722509c 100644
> --- a/drivers/acpi/thermal.c
> +++ b/drivers/acpi/thermal.c
> @@ -111,7 +111,7 @@ struct acpi_thermal_passive {
> unsigned long temperature;
> unsigned long tc1;
> unsigned long tc2;
> - unsigned long tsp;
> + unsigned long sampling_period;
> bool valid;
> };
>
> @@ -289,11 +289,18 @@ static int acpi_thermal_trips_update(struct acpi_thermal *tz, int flag)
> tz->trips.passive.tc2 = tmp;
>
> status = acpi_evaluate_integer(tz->device->handle,
> - "_TSP", NULL, &tmp);
> - if (ACPI_FAILURE(status))
> - tz->trips.passive.valid = false;
> - else
> - tz->trips.passive.tsp = tmp;
> + "_TFP", NULL, &tmp);
> + if (ACPI_FAILURE(status)) {
> + status = acpi_evaluate_integer(tz->device->handle,
> + "_TSP", NULL, &tmp);
> + if (ACPI_FAILURE(status))
> + tz->trips.passive.valid = false;
> + else
> + tz->trips.passive.sampling_period = tmp * 100;
> +
> + } else {
> + tz->trips.passive.sampling_period = tmp;
> + }
> }
> }
> }
> @@ -765,7 +772,7 @@ static int acpi_thermal_register_thermal_zone(struct acpi_thermal *tz)
> if (tz->trips.passive.valid)
> tz->thermal_zone = thermal_zone_device_register("acpitz", trips, 0, tz,
> &acpi_thermal_zone_ops, NULL,
> - tz->trips.passive.tsp * 100,
> + tz->trips.passive.sampling_period,
> tz->polling_frequency * 100);
> else
> tz->thermal_zone =
> --

So this needs to be rebased on top of the current linux-next branch in
linux-pm.git or on top of the acpi-thermal branch in there.