Re: [PATCH v2] thermal: core: Call monitor_thermal_zone() if zone temperature is invalid

[Daniel Lezcano <daniel.lezcano@linaro.org>]

On 28/06/2024 14:10, Rafael J. Wysocki wrote:
> From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
> 
> Commit 202aa0d4bb53 ("thermal: core: Do not call handle_thermal_trip()
> if zone temperature is invalid") caused __thermal_zone_device_update()
> to return early if the current thermal zone temperature was invalid.
> 
> This was done to avoid running handle_thermal_trip() and governor
> callbacks in that case which led to confusion.  However, it went too
> far because monitor_thermal_zone() still needs to be called even when
> the zone temperature is invalid to ensure that it will be updated
> eventually in case thermal polling is enabled and the driver has no
> other means to notify the core of zone temperature changes (for example,
> it does not register an interrupt handler or ACPI notifier).
> 
> Also if the .set_trips() zone callback is expected to set up monitoring
> interrupts for a thermal zone, it has to be provided with valid
> boundaries and that can only happen if the zone temperature is known.
> 
> Accordingly, to ensure that __thermal_zone_device_update() will
> run again after a failing zone temperature check, make it call
> monitor_thermal_zone() regardless of whether or not the zone
> temperature is valid and make the latter schedule a thermal zone
> temperature update if the zone temperature is invalid even if
> polling is not enabled for the thermal zone.
> 
> Fixes: 202aa0d4bb53 ("thermal: core: Do not call handle_thermal_trip() if zone temperature is invalid")
> Reported-by: Daniel Lezcano <daniel.lezcano@linaro.org>
> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Tested-by: Daniel Lezcano <daniel.lezcano@linaro.org>

-- 
<http://www.linaro.org/> Linaro.org │ Open source software for ARM SoCs

Follow Linaro:  <http://www.facebook.com/pages/Linaro> Facebook |
<http://twitter.com/#!/linaroorg> Twitter |
<http://www.linaro.org/linaro-blog/> Blog