4.4-stable review patch. If anyone has any objections, please let me know.
------------------ From: Zhang Rui <[email protected]> commit bb431ba26c5cd0a17c941ca6c3a195a3a6d5d461 upstream. After thermal zone device registered, as we have not read any temperature before, thus tz->temperature should not be 0, which actually means 0C, and thermal trend is not available. In this case, we need specially handling for the first thermal_zone_device_update(). Both thermal core framework and step_wise governor is enhanced to handle this. And since the step_wise governor is the only one that uses trends, so it's the only thermal governor that needs to be updated. Tested-by: Manuel Krause <[email protected]> Tested-by: szegad <[email protected]> Tested-by: prash <[email protected]> Tested-by: amish <[email protected]> Tested-by: Matthias <[email protected]> Reviewed-by: Javi Merino <[email protected]> Signed-off-by: Zhang Rui <[email protected]> Signed-off-by: Chen Yu <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/thermal/step_wise.c | 17 +++++++++++++++-- drivers/thermal/thermal_core.c | 19 +++++++++++++++++-- drivers/thermal/thermal_core.h | 1 + include/linux/thermal.h | 3 +++ 4 files changed, 36 insertions(+), 4 deletions(-) --- a/drivers/thermal/step_wise.c +++ b/drivers/thermal/step_wise.c @@ -63,6 +63,19 @@ static unsigned long get_target_state(st next_target = instance->target; dev_dbg(&cdev->device, "cur_state=%ld\n", cur_state); + if (!instance->initialized) { + if (throttle) { + next_target = (cur_state + 1) >= instance->upper ? + instance->upper : + ((cur_state + 1) < instance->lower ? + instance->lower : (cur_state + 1)); + } else { + next_target = THERMAL_NO_TARGET; + } + + return next_target; + } + switch (trend) { case THERMAL_TREND_RAISING: if (throttle) { @@ -149,7 +162,7 @@ static void thermal_zone_trip_update(str dev_dbg(&instance->cdev->device, "old_target=%d, target=%d\n", old_target, (int)instance->target); - if (old_target == instance->target) + if (instance->initialized && old_target == instance->target) continue; /* Activate a passive thermal instance */ @@ -161,7 +174,7 @@ static void thermal_zone_trip_update(str instance->target == THERMAL_NO_TARGET) update_passive_instance(tz, trip_type, -1); - + instance->initialized = true; instance->cdev->updated = false; /* cdev needs update */ } --- a/drivers/thermal/thermal_core.c +++ b/drivers/thermal/thermal_core.c @@ -532,8 +532,22 @@ static void update_temperature(struct th mutex_unlock(&tz->lock); trace_thermal_temperature(tz); - dev_dbg(&tz->device, "last_temperature=%d, current_temperature=%d\n", - tz->last_temperature, tz->temperature); + if (tz->last_temperature == THERMAL_TEMP_INVALID) + dev_dbg(&tz->device, "last_temperature N/A, current_temperature=%d\n", + tz->temperature); + else + dev_dbg(&tz->device, "last_temperature=%d, current_temperature=%d\n", + tz->last_temperature, tz->temperature); +} + +static void thermal_zone_device_reset(struct thermal_zone_device *tz) +{ + struct thermal_instance *pos; + + tz->temperature = THERMAL_TEMP_INVALID; + tz->passive = 0; + list_for_each_entry(pos, &tz->thermal_instances, tz_node) + pos->initialized = false; } void thermal_zone_device_update(struct thermal_zone_device *tz) @@ -1900,6 +1914,7 @@ struct thermal_zone_device *thermal_zone INIT_DELAYED_WORK(&(tz->poll_queue), thermal_zone_device_check); + thermal_zone_device_reset(tz); thermal_zone_device_update(tz); return tz; --- a/drivers/thermal/thermal_core.h +++ b/drivers/thermal/thermal_core.h @@ -41,6 +41,7 @@ struct thermal_instance { struct thermal_zone_device *tz; struct thermal_cooling_device *cdev; int trip; + bool initialized; unsigned long upper; /* Highest cooling state for this trip point */ unsigned long lower; /* Lowest cooling state for this trip point */ unsigned long target; /* expected cooling state */ --- a/include/linux/thermal.h +++ b/include/linux/thermal.h @@ -43,6 +43,9 @@ /* Default weight of a bound cooling device */ #define THERMAL_WEIGHT_DEFAULT 0 +/* use value, which < 0K, to indicate an invalid/uninitialized temperature */ +#define THERMAL_TEMP_INVALID -274000 + /* Unit conversion macros */ #define DECI_KELVIN_TO_CELSIUS(t) ({ \ long _t = (t); \
