> On Dec 1, 2020, at 02:39, Srinivas Pandruvada > <[email protected]> wrote: > > On Tue, 2020-12-01 at 02:22 +0800, Kai-Heng Feng wrote: >>> On Dec 1, 2020, at 02:13, Srinivas Pandruvada < >>> [email protected]> wrote: >> >> [snipped] >> >>>>> What about creating an new callback >>>>> >>>>> enum thermal_trip_status { >>>>> THERMAL_TRIP_DISABLED = 0, >>>>> THERMAL_TRIP_ENABLED, >>>>> }; >>>>> >>>>> int get_trip_status(struct thermal_zone_device *, int trip, >>>>> enum >>>>> thermal_trip_status *state); >>>>> >>>>> Then in >>>>> static void handle_thermal_trip(struct thermal_zone_device *tz, >>>>> int >>>>> trip) >>>>> { >>>>> >>>>> /* before tz->ops->get_trip_temp(tz, trip, &trip_temp); */ >>>>> if (tz->ops->get_trip_status) { >>>>> enum thermal_trip_status *status; >>>>> >>>>> if (!tz->ops->get_trip_status(tz, trip, &status)) { >>>>> if (status == THERMAL_TRIP_DISABLED) >>>>> return; >>>>> } >>>>> } >>>>> ... >>>>> ... >>>>> >>>>> } >>>>> >>>>> >>>>> This callback will help the cases: >>>>> - Allows drivers to selectively disable certain trips during >>>>> init >>>>> state >>>>> or system resume where there can be spikes or always. int340x >>>>> drivers >>>>> can disable always. >>>> >>>> This sounds really great. This is indeed can happen on system >>>> resume, >>>> before userspace process thaw. >>>> >>>>> - Still give options for drivers to handle critical trip even >>>>> if >>>>> they >>>>> are bound to user space governors. User space process may be >>>>> dead, >>>>> so >>>>> still allow kernel to process graceful shutdown >>>> >>>> To make the scenario happen, do we need a new sysfs to let >>>> usespace >>>> enable it with THERMAL_TRIP_ENABLED? >>> This should be drivers call not user space. >> >> Understood. So after thermal_zone_device_register(), the driver can >> decide to what to return on get_trip_temp(). > get_trip_status() > >> Let me work on a new patch if there's no other concern. > Better to wait for confirmation from Daniel and others. Daniel, Do you like Srinivas' proposed solution? I hope we can find a solution in upstream kernel soon. Kai-Heng > > Thanks, > Srinivas > >> >> Kai-Heng >> >>> Thanks, >>> Srinivas
