On ?, 2016-06-06 at 19:44 +0800, Caesar Wang wrote: > From: Sascha Hauer <s.hauer at pengutronix.de> > > This adds support for hardware-tracked trip points to the device tree > thermal sensor framework. > > The framework supports an arbitrary number of trip points. Whenever > the current temperature is updated, the trip points immediately > below and above the current temperature are found. A .set_trips > callback is then called with the temperatures. If there is no trip > point above or below the current temperature, the passed trip > temperature will be -INT_MAX or INT_MAX respectively. In this > callback, > the driver should program the hardware such that it is notified > when either of these trip points are triggered. When a trip point > is triggered, the driver should call `thermal_zone_device_update' > for the respective thermal zone. This will cause the trip points > to be updated again. > > If .set_trips is not implemented, the framework behaves as before. > > This patch is based on an earlier version from Mikko Perttunen > <mikko.perttunen at kapsi.fi> > > Signed-off-by: Sascha Hauer <s.hauer at pengutronix.de> > Signed-off-by: Caesar Wang <wxt at rock-chips.com> > Cc: Zhang Rui <rui.zhang at intel.com> > Cc: Eduardo Valentin <edubezval at gmail.com> > Cc: linux-pm at vger.kernel.org > > --- > > Changes in v5: > - add the lock for thermal_zone_set_trips function. > - change based on next kernel. > > Changes in v4: > - Missing the lock added in v3. > > Changes in v3: > - as Javi comments on https://patchwork.kernel.org/patch/9001281/. > - add the lock for preventing the called from multi placce > - add the note for pre_low/high_trip. > > Changes in v2: > - update the sysfs-api.txt for set_trips. > > ?Documentation/thermal/sysfs-api.txt |??7 +++++ > ?drivers/thermal/thermal_core.c??????| 54 > +++++++++++++++++++++++++++++++++++++ > ?drivers/thermal/thermal_sysfs.c?????|??3 +++ > ?include/linux/thermal.h?????????????| 10 +++++++ > ?4 files changed, 74 insertions(+) > > diff --git a/Documentation/thermal/sysfs-api.txt > b/Documentation/thermal/sysfs-api.txt > index efc3f3d..75d8838 100644 > --- a/Documentation/thermal/sysfs-api.txt > +++ b/Documentation/thermal/sysfs-api.txt > @@ -49,6 +49,9 @@ temperature) and throttle appropriate devices. > ? .bind: bind the thermal zone device with a thermal cooling > device. > ? .unbind: unbind the thermal zone device with a thermal > cooling device. > ? .get_temp: get the current temperature of the thermal zone. > + .set_trips: set the trip points window. Whenever the current > temperature > + ????is updated, the trip points immediately below > and above the > + ????current temperature are found. > ? .get_mode: get the current mode (enabled/disabled) of the > thermal zone. > ? ????- "enabled" means the kernel thermal management is > enabled. > ? ????- "disabled" will prevent kernel thermal driver action > upon trip points > @@ -95,6 +98,10 @@ temperature) and throttle appropriate devices. > ? get_temp: a pointer to a function > that reads the > ? sensor temperature. This is > mandatory > ? callback provided by sensor > driver. > + set_trips:??????a pointer to a function that > sets a > + temperature window. When > this window is > + left the driver must inform > the thermal > + core via > thermal_zone_device_update. > ? get_trend:? a pointer to a function > that reads the > ? sensor temperature trend. > ? set_emul_temp: a pointer to a > function that sets > diff --git a/drivers/thermal/thermal_core.c > b/drivers/thermal/thermal_core.c > index 792aab7..e69aee2 100644 > --- a/drivers/thermal/thermal_core.c > +++ b/drivers/thermal/thermal_core.c > @@ -368,6 +368,56 @@ static void handle_thermal_trip(struct > thermal_zone_device *tz, int trip) > ? monitor_thermal_zone(tz); > ?} > ? > +void thermal_zone_set_trips(struct thermal_zone_device *tz) > +{ > + int low = -INT_MAX; > + int high = INT_MAX; > + int trip_temp, hysteresis; > + int i, ret; > + > + mutex_lock(&tz->lock); > + > + if (!tz->ops->set_trips) > + goto exit; > + if (!tz->ops->get_trip_hyst) goto exit; otherwise, the patch looks good to me. thanks, rui > + for (i = 0; i < tz->trips; i++) { > + int trip_low; > + > + tz->ops->get_trip_temp(tz, i, &trip_temp); > + tz->ops->get_trip_hyst(tz, i, &hysteresis); > + > + trip_low = trip_temp - hysteresis; > + > + if (trip_low < tz->temperature && trip_low > low) > + low = trip_low; > + > + if (trip_temp > tz->temperature && trip_temp < high) > + high = trip_temp; > + } > + > + /* No need to change trip points */ > + if (tz->prev_low_trip == low && tz->prev_high_trip == high) > + goto exit; > + > + tz->prev_low_trip = low; > + tz->prev_high_trip = high; > + > + dev_dbg(&tz->device, "new temperature boundaries: %d < x < > %d\n", > + low, high); > + > + /* > + ?* Set a temperature window. When this window is left the > driver > + ?* must inform the thermal core via > thermal_zone_device_update. > + ?*/ > + ret = tz->ops->set_trips(tz, low, high); > + if (ret) > + dev_err(&tz->device, "Failed to set trips: %d\n", > ret); > + > +exit: > + mutex_unlock(&tz->lock); > +} > +EXPORT_SYMBOL_GPL(thermal_zone_set_trips); > + > ?static void update_temperature(struct thermal_zone_device *tz) > ?{ > ? int temp, ret; > @@ -417,6 +467,8 @@ void thermal_zone_device_update(struct > thermal_zone_device *tz) > ? > ? update_temperature(tz); > ? > + thermal_zone_set_trips(tz); > + > ? for (count = 0; count < tz->trips; count++) > ? handle_thermal_trip(tz, count); > ?} > @@ -1175,6 +1227,8 @@ thermal_zone_device_register(const char *type, > int trips, int mask, > ? tz->trips = trips; > ? tz->passive_delay = passive_delay; > ? tz->polling_delay = polling_delay; > + tz->prev_low_trip = INT_MAX; > + tz->prev_high_trip = -INT_MAX; > ? > ? /* sys I/F */ > ? /* Add nodes that are always present via .groups */ > diff --git a/drivers/thermal/thermal_sysfs.c > b/drivers/thermal/thermal_sysfs.c > index 743df50..33bbe30 100644 > --- a/drivers/thermal/thermal_sysfs.c > +++ b/drivers/thermal/thermal_sysfs.c > @@ -219,6 +219,9 @@ trip_point_hyst_store(struct device *dev, struct > device_attribute *attr, > ? ret = tz->ops->set_trip_hyst(tz, trip, temperature); > ? mutex_unlock(&tz->lock); > ? > + if (!ret) > + thermal_zone_set_trips(tz); > + > ? return ret ? ret : count; > ?} > ? > diff --git a/include/linux/thermal.h b/include/linux/thermal.h > index ea667b6..780e69d 100644 > --- a/include/linux/thermal.h > +++ b/include/linux/thermal.h > @@ -99,6 +99,7 @@ struct thermal_zone_device_ops { > ? int (*unbind) (struct thermal_zone_device *, > ? ???????struct thermal_cooling_device *); > ? int (*get_temp) (struct thermal_zone_device *, int *); > + int (*set_trips) (struct thermal_zone_device *, int, int); > ? int (*get_mode) (struct thermal_zone_device *, > ? ?enum thermal_device_mode *); > ? int (*set_mode) (struct thermal_zone_device *, > @@ -169,6 +170,10 @@ struct thermal_attr { > ? * @last_temperature: previous temperature read > ? * @emul_temperature: emulated temperature when using > CONFIG_THERMAL_EMULATION > ? * @passive: 1 if you've crossed a passive trip > point, 0 otherwise. > + * @prev_low_trip: the low current temperature if you've > crossed a passive > + trip point. > + * @prev_high_trip: the above current temperature if you've > crossed a > + passive trip point. > ? * @forced_passive: If > 0, temperature at which to switch on > all ACPI > ? * processor cooling devices.??Currently only > used by the > ? * step-wise governor. > @@ -201,6 +206,8 @@ struct thermal_zone_device { > ? int last_temperature; > ? int emul_temperature; > ? int passive; > + int prev_low_trip; > + int prev_high_trip; > ? unsigned int forced_passive; > ? atomic_t need_update; > ? struct thermal_zone_device_ops *ops; > @@ -428,6 +435,7 @@ int thermal_zone_bind_cooling_device(struct > thermal_zone_device *, int, > ?int thermal_zone_unbind_cooling_device(struct thermal_zone_device *, > int, > ? ???????struct thermal_cooling_device > *); > ?void thermal_zone_device_update(struct thermal_zone_device *); > +void thermal_zone_set_trips(struct thermal_zone_device *); > ? > ?struct thermal_cooling_device *thermal_cooling_device_register(char > *, void *, > ? const struct thermal_cooling_device_ops *); > @@ -477,6 +485,8 @@ static inline int > thermal_zone_unbind_cooling_device( > ?{ return -ENODEV; } > ?static inline void thermal_zone_device_update(struct > thermal_zone_device *tz) > ?{ } > +static inline void thermal_zone_set_trips(struct thermal_zone_device > *tz) > +{ } > ?static inline struct thermal_cooling_device * > ?thermal_cooling_device_register(char *type, void *devdata, > ? const struct thermal_cooling_device_ops *ops)