Hi Caesar, On Wed, May 25, 2016 at 11:47:45AM +0800, Caesar Wang wrote: > From: Sascha Hauer <s.hauer@xxxxxxxxxxxxxx> > > 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@xxxxxxxx> > > Signed-off-by: Sascha Hauer <s.hauer@xxxxxxxxxxxxxx> > Signed-off-by: Caesar Wang <wxt@xxxxxxxxxxxxxx> > Cc: Zhang Rui <rui.zhang@xxxxxxxxx> > Cc: Eduardo Valentin <edubezval@xxxxxxxxx> > Cc: linux-pm@xxxxxxxxxxxxxxx > > --- > > 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 | 52 +++++++++++++++++++++++++++++++++++++ > include/linux/thermal.h | 7 +++++ > 3 files changed, 66 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); In the v2 review (http://article.gmane.org/gmane.linux.documentation/38442) you agreed to add locking but you haven't done it. Maybe you sent the wrong version? Cheers, Javi -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
