| Message ID | 1462268013-14992-2-git-send-email-wxt@rock-chips.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, May 03, 2016 at 05:33:29PM +0800, Caesar Wang wrote: > From: Sascha Hauer <s.hauer@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@kapsi.fi> > > Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de> > Signed-off-by: Caesar Wang <wxt@rock-chips.com> > Cc: Zhang Rui <rui.zhang@intel.com> > Cc: Eduardo Valentin <edubezval@gmail.com> > Cc: linux-pm@vger.kernel.org > > --- > > Changes in v2: > - update the sysfs-api.txt for set_trips > > Documentation/thermal/sysfs-api.txt | 7 +++++ > drivers/thermal/thermal_core.c | 52 +++++++++++++++++++++++++++++++++++++ > include/linux/thermal.h | 3 +++ > 3 files changed, 62 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 5133cd1..e5bfbd3 100644 > --- a/drivers/thermal/thermal_core.c > +++ b/drivers/thermal/thermal_core.c > @@ -520,6 +520,51 @@ exit: > } > EXPORT_SYMBOL_GPL(thermal_zone_get_temp); > > +static void thermal_zone_set_trips(struct thermal_zone_device *tz) > +{ > + int low = -INT_MAX; > + int high = INT_MAX; > + int trip_temp, hysteresis; > + int temp = tz->temperature; > + int i, ret; > + > + if (!tz->ops->set_trips) > + return; > + > + 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 < temp && trip_low > low) > + low = trip_low; > + > + if (trip_temp > temp && trip_temp < high) > + high = trip_temp; > + } > + > + /* No need to change trip points */ > + if (tz->prev_low_trip == low && tz->prev_high_trip == high) > + return; > + > + 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); This function can be called at the same time from multiple places so it should be reentrant. I think you should call mutex_lock(tz->lock) before "if (tz->prev_low_trip == low && ..." and unlock it here. > +} > + > static void update_temperature(struct thermal_zone_device *tz) > { > int temp, ret; > @@ -569,6 +614,8 @@ 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); > } > @@ -754,6 +801,9 @@ trip_point_hyst_store(struct device *dev, struct device_attribute *attr, > */ > ret = tz->ops->set_trip_hyst(tz, trip, temperature); > > + if (!ret) > + thermal_zone_set_trips(tz); > + You should add a similar call to thermal_zone_set_trips() in trip_point_temp_store() > return ret ? ret : count; > } > > @@ -1843,6 +1893,8 @@ struct thermal_zone_device *thermal_zone_device_register(const char *type, > 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; > /* A new thermal zone needs to be updated anyway. */ > atomic_set(&tz->need_update, 1); > > diff --git a/include/linux/thermal.h b/include/linux/thermal.h > index e45abe7..e258359 100644 > --- a/include/linux/thermal.h > +++ b/include/linux/thermal.h > @@ -98,6 +98,7 @@ 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 *, > @@ -199,6 +200,8 @@ struct thermal_zone_device { > int last_temperature; > int emul_temperature; > int passive; > + int prev_low_trip; > + int prev_high_trip; Please document these fields in the kerneldoc comment before struct thermal_zone_device. > unsigned int forced_passive; > atomic_t need_update; > struct thermal_zone_device_ops *ops; Cheers, Javi
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 5133cd1..e5bfbd3 100644 --- a/drivers/thermal/thermal_core.c +++ b/drivers/thermal/thermal_core.c @@ -520,6 +520,51 @@ exit: } EXPORT_SYMBOL_GPL(thermal_zone_get_temp); +static void thermal_zone_set_trips(struct thermal_zone_device *tz) +{ + int low = -INT_MAX; + int high = INT_MAX; + int trip_temp, hysteresis; + int temp = tz->temperature; + int i, ret; + + if (!tz->ops->set_trips) + return; + + 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 < temp && trip_low > low) + low = trip_low; + + if (trip_temp > temp && trip_temp < high) + high = trip_temp; + } + + /* No need to change trip points */ + if (tz->prev_low_trip == low && tz->prev_high_trip == high) + return; + + 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); +} + static void update_temperature(struct thermal_zone_device *tz) { int temp, ret; @@ -569,6 +614,8 @@ 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); } @@ -754,6 +801,9 @@ trip_point_hyst_store(struct device *dev, struct device_attribute *attr, */ ret = tz->ops->set_trip_hyst(tz, trip, temperature); + if (!ret) + thermal_zone_set_trips(tz); + return ret ? ret : count; } @@ -1843,6 +1893,8 @@ struct thermal_zone_device *thermal_zone_device_register(const char *type, 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; /* A new thermal zone needs to be updated anyway. */ atomic_set(&tz->need_update, 1); diff --git a/include/linux/thermal.h b/include/linux/thermal.h index e45abe7..e258359 100644 --- a/include/linux/thermal.h +++ b/include/linux/thermal.h @@ -98,6 +98,7 @@ 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 *, @@ -199,6 +200,8 @@ 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;