| Message ID | 1427385240-6086-13-git-send-email-s.hauer@pengutronix.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Thu, Mar 26, 2015 at 04:53:59PM +0100, Sascha Hauer wrote: > 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 ULONG_MAX or 0 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> > --- > drivers/thermal/thermal_core.c | 41 +++++++++++++++++++++++++++++++++++++++++ > include/linux/thermal.h | 3 +++ > 2 files changed, 44 insertions(+) > > diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c > index dcdf45e..7138f8f 100644 > --- a/drivers/thermal/thermal_core.c > +++ b/drivers/thermal/thermal_core.c > @@ -434,6 +434,45 @@ int thermal_zone_get_temp(struct thermal_zone_device *tz, unsigned long *temp) > } > EXPORT_SYMBOL_GPL(thermal_zone_get_temp); > > +static void thermal_zone_set_trips(struct thermal_zone_device *tz) > +{ > + unsigned long low = 0; > + unsigned long high = ULONG_MAX; > + unsigned long trip_temp, hysteresis; > + unsigned long temp = tz->temperature; > + int i; > + > + if (!tz->ops->set_trips) > + return; > + > + /* No need to change trip points */ > + if (temp > tz->prev_low_trip && temp < tz->prev_high_trip) > + return; > + > + for (i = 0; i < tz->trips; i++) { > + unsigned long 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; > + } > + > + tz->prev_low_trip = low; > + tz->prev_high_trip = high; > + > + dev_dbg(&tz->device, "new temperature boundaries: %lu < x < %lu\n", > + low, high); > + > + tz->ops->set_trips(tz, low, high); > +} > + > void thermal_zone_device_update(struct thermal_zone_device *tz) > { > int count; > @@ -460,6 +499,8 @@ void thermal_zone_device_update(struct thermal_zone_device *tz) > dev_dbg(&tz->device, "last_temperature=%lu, current_temperature=%lu\n", > tz->last_temperature, tz->temperature); > > + thermal_zone_set_trips(tz); Do we need to lock the tz->lock to perform this operation of setting the hardware trip points? > + > for (count = 0; count < tz->trips; count++) > handle_thermal_trip(tz, count); > } > diff --git a/include/linux/thermal.h b/include/linux/thermal.h > index ac2897c..b870702 100644 > --- a/include/linux/thermal.h > +++ b/include/linux/thermal.h > @@ -87,6 +87,7 @@ struct thermal_zone_device_ops { > int (*unbind) (struct thermal_zone_device *, > struct thermal_cooling_device *); > int (*get_temp) (struct thermal_zone_device *, unsigned long *); > + int (*set_trips) (struct thermal_zone_device *, unsigned long, unsigned long); > int (*get_mode) (struct thermal_zone_device *, > enum thermal_device_mode *); > int (*set_mode) (struct thermal_zone_device *, > @@ -183,6 +184,8 @@ struct thermal_zone_device { > unsigned long temperature; > unsigned long last_temperature; > unsigned long emul_temperature; > + unsigned long prev_low_trip; > + unsigned long prev_high_trip; > int passive; > unsigned int forced_passive; > const struct thermal_zone_device_ops *ops; > -- > 2.1.4 >
Hi Sascha, On Thu, Mar 26, 2015 at 04:53:59PM +0100, Sascha Hauer wrote: > 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 ULONG_MAX or 0 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> > --- > drivers/thermal/thermal_core.c | 41 +++++++++++++++++++++++++++++++++++++++++ > include/linux/thermal.h | 3 +++ > 2 files changed, 44 insertions(+) > > diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c > index dcdf45e..7138f8f 100644 > --- a/drivers/thermal/thermal_core.c > +++ b/drivers/thermal/thermal_core.c > @@ -434,6 +434,45 @@ int thermal_zone_get_temp(struct thermal_zone_device *tz, unsigned long *temp) > } > EXPORT_SYMBOL_GPL(thermal_zone_get_temp); > > +static void thermal_zone_set_trips(struct thermal_zone_device *tz) > +{ > + unsigned long low = 0; > + unsigned long high = ULONG_MAX; > + unsigned long trip_temp, hysteresis; > + unsigned long temp = tz->temperature; > + int i; > + > + if (!tz->ops->set_trips) > + return; > + > + /* No need to change trip points */ > + if (temp > tz->prev_low_trip && temp < tz->prev_high_trip) > + return; I see that you don't actually initialize prev_{low,high}_trip during device initialization, so they both start out as zero. I suppose that works here, mostly by coincidence, because it means we'll still always recalculate trip points the first time, but might it make sense to explicitly initialize them to: low = ULONG_MAX high = 0 at init time? (Or, if these change to integer: INT_MAX and -INT_MAX?) Thanks, Brian > + > + for (i = 0; i < tz->trips; i++) { > + unsigned long 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; > + } > + > + tz->prev_low_trip = low; > + tz->prev_high_trip = high; > + > + dev_dbg(&tz->device, "new temperature boundaries: %lu < x < %lu\n", > + low, high); > + > + tz->ops->set_trips(tz, low, high); > +} > + > void thermal_zone_device_update(struct thermal_zone_device *tz) > { > int count; > @@ -460,6 +499,8 @@ void thermal_zone_device_update(struct thermal_zone_device *tz) > dev_dbg(&tz->device, "last_temperature=%lu, current_temperature=%lu\n", > tz->last_temperature, tz->temperature); > > + thermal_zone_set_trips(tz); > + > for (count = 0; count < tz->trips; count++) > handle_thermal_trip(tz, count); > } > diff --git a/include/linux/thermal.h b/include/linux/thermal.h > index ac2897c..b870702 100644 > --- a/include/linux/thermal.h > +++ b/include/linux/thermal.h > @@ -87,6 +87,7 @@ struct thermal_zone_device_ops { > int (*unbind) (struct thermal_zone_device *, > struct thermal_cooling_device *); > int (*get_temp) (struct thermal_zone_device *, unsigned long *); > + int (*set_trips) (struct thermal_zone_device *, unsigned long, unsigned long); > int (*get_mode) (struct thermal_zone_device *, > enum thermal_device_mode *); > int (*set_mode) (struct thermal_zone_device *, > @@ -183,6 +184,8 @@ struct thermal_zone_device { > unsigned long temperature; > unsigned long last_temperature; > unsigned long emul_temperature; > + unsigned long prev_low_trip; > + unsigned long prev_high_trip; > int passive; > unsigned int forced_passive; > const struct thermal_zone_device_ops *ops; > -- > 2.1.4 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-pm" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c index dcdf45e..7138f8f 100644 --- a/drivers/thermal/thermal_core.c +++ b/drivers/thermal/thermal_core.c @@ -434,6 +434,45 @@ int thermal_zone_get_temp(struct thermal_zone_device *tz, unsigned long *temp) } EXPORT_SYMBOL_GPL(thermal_zone_get_temp); +static void thermal_zone_set_trips(struct thermal_zone_device *tz) +{ + unsigned long low = 0; + unsigned long high = ULONG_MAX; + unsigned long trip_temp, hysteresis; + unsigned long temp = tz->temperature; + int i; + + if (!tz->ops->set_trips) + return; + + /* No need to change trip points */ + if (temp > tz->prev_low_trip && temp < tz->prev_high_trip) + return; + + for (i = 0; i < tz->trips; i++) { + unsigned long 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; + } + + tz->prev_low_trip = low; + tz->prev_high_trip = high; + + dev_dbg(&tz->device, "new temperature boundaries: %lu < x < %lu\n", + low, high); + + tz->ops->set_trips(tz, low, high); +} + void thermal_zone_device_update(struct thermal_zone_device *tz) { int count; @@ -460,6 +499,8 @@ void thermal_zone_device_update(struct thermal_zone_device *tz) dev_dbg(&tz->device, "last_temperature=%lu, current_temperature=%lu\n", tz->last_temperature, tz->temperature); + thermal_zone_set_trips(tz); + for (count = 0; count < tz->trips; count++) handle_thermal_trip(tz, count); } diff --git a/include/linux/thermal.h b/include/linux/thermal.h index ac2897c..b870702 100644 --- a/include/linux/thermal.h +++ b/include/linux/thermal.h @@ -87,6 +87,7 @@ struct thermal_zone_device_ops { int (*unbind) (struct thermal_zone_device *, struct thermal_cooling_device *); int (*get_temp) (struct thermal_zone_device *, unsigned long *); + int (*set_trips) (struct thermal_zone_device *, unsigned long, unsigned long); int (*get_mode) (struct thermal_zone_device *, enum thermal_device_mode *); int (*set_mode) (struct thermal_zone_device *, @@ -183,6 +184,8 @@ struct thermal_zone_device { unsigned long temperature; unsigned long last_temperature; unsigned long emul_temperature; + unsigned long prev_low_trip; + unsigned long prev_high_trip; int passive; unsigned int forced_passive; const struct thermal_zone_device_ops *ops;
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 ULONG_MAX or 0 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> --- drivers/thermal/thermal_core.c | 41 +++++++++++++++++++++++++++++++++++++++++ include/linux/thermal.h | 3 +++ 2 files changed, 44 insertions(+)