From mboxrd@z Thu Jan 1 00:00:00 1970 From: Zhang Rui Subject: Re: [PATCH V4 04/13] Thermal: Introduce .get_trend() callback. Date: Wed, 01 Aug 2012 10:42:33 +0800 Message-ID: <1343788953.1682.491.camel@rui.sh.intel.com> References: <1343292083-2047-1-git-send-email-rui.zhang@intel.com> <1343292083-2047-5-git-send-email-rui.zhang@intel.com> <201207262211.06597.rjw@sisk.pl> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from mga14.intel.com ([143.182.124.37]:8650 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752676Ab2HAClU (ORCPT ); Tue, 31 Jul 2012 22:41:20 -0400 In-Reply-To: <201207262211.06597.rjw@sisk.pl> Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: "Rafael J. Wysocki" Cc: Matthew Garrett , Len Brown , R Durgadoss , Eduardo Valentin , Amit Kachhap , Wei Ni , linux-acpi@vger.kernel.org, linux-pm@vger.kernel.org On =E5=9B=9B, 2012-07-26 at 22:11 +0200, Rafael J. Wysocki wrote: > On Thursday, July 26, 2012, Zhang Rui wrote: > > According to ACPI spec, tc1 and tc2 are used by OSPM > > to anticipate the temperature trends. > > We introduced the same concept to the generic thermal layer > > for passive cooling, but now it seems that these values > > are hard to be used on other platforms. > >=20 > > So We introduce .get_trend() as a more general solution. > >=20 > > For the platform thermal drivers that have their own way to > > anticipate the temperature trends, they should provide > > their own .get_trend() callback. > > Or else, we will calculate the temperature trends by simply > > comparing the current temperature and the cached previous > > temperature reading. >=20 > As far as the code is concerned: >=20 > Reviewed-by: Rafael J. Wysocki >=20 > I wonder, though, if there are any users of the thermal core currentl= y in the > tree who should introduce their own .get_trend() callbacks? >=20 No, for now. But there will be soon. :) thanks, rui > Rafael >=20 >=20 > > Signed-off-by: Zhang Rui > > --- > > drivers/acpi/thermal.c | 33 +++++++++++++++++++++++++++++= ++++ > > drivers/thermal/thermal_sys.c | 19 +++++++++++++++++-- > > include/linux/thermal.h | 9 +++++++++ > > 3 files changed, 59 insertions(+), 2 deletions(-) > >=20 > > diff --git a/drivers/acpi/thermal.c b/drivers/acpi/thermal.c > > index b48ec3e..0c49e42 100644 > > --- a/drivers/acpi/thermal.c > > +++ b/drivers/acpi/thermal.c > > @@ -704,6 +704,38 @@ static int thermal_get_crit_temp(struct therma= l_zone_device *thermal, > > return -EINVAL; > > } > > =20 > > +static int thermal_get_trend(struct thermal_zone_device *thermal, > > + int trip, enum thermal_trend *trend) > > +{ > > + struct acpi_thermal *tz =3D thermal->devdata; > > + enum thermal_trip_type type; > > + int i; > > + > > + if (thermal_get_trip_type(thermal, trip, &type)) > > + return -EINVAL; > > + > > + /* Only PASSIVE trip points need TREND */ > > + if (type !=3D THERMAL_TRIP_PASSIVE) > > + return -EINVAL; > > + > > + /* > > + * tz->temperature has already been updated by generic thermal la= yer, > > + * before this callback being invoked > > + */ > > + i =3D (tz->trips.passive.tc1 * (tz->temperature - tz->last_temper= ature)) > > + + (tz->trips.passive.tc2 > > + * (tz->temperature - tz->trips.passive.temperature)); > > + > > + if (i > 0) > > + *trend =3D THERMAL_TREND_RAISING; > > + else if (i < 0) > > + *trend =3D THERMAL_TREND_DROPPING; > > + else > > + *trend =3D THERMAL_TREND_STABLE; > > + return 0; > > +} > > + > > + > > static int thermal_notify(struct thermal_zone_device *thermal, int= trip, > > enum thermal_trip_type trip_type) > > { > > @@ -836,6 +868,7 @@ static const struct thermal_zone_device_ops acp= i_thermal_zone_ops =3D { > > .get_trip_type =3D thermal_get_trip_type, > > .get_trip_temp =3D thermal_get_trip_temp, > > .get_crit_temp =3D thermal_get_crit_temp, > > + .get_trend =3D thermal_get_trend, > > .notify =3D thermal_notify, > > }; > > =20 > > diff --git a/drivers/thermal/thermal_sys.c b/drivers/thermal/therma= l_sys.c > > index 62b4279..68c93d4 100644 > > --- a/drivers/thermal/thermal_sys.c > > +++ b/drivers/thermal/thermal_sys.c > > @@ -723,6 +723,20 @@ static void thermal_zone_device_passive(struct= thermal_zone_device *tz, > > struct thermal_cooling_device *cdev; > > long state, max_state; > > =20 > > + if (!tz->ops->get_trend || > > + tz->ops->get_trend(tz, trip, (enum thermal_trend *)&trend)) { > > + /* > > + * compare the current temperature and previous temperature > > + * to get the thermal trend, if no special requirement > > + */ > > + if (tz->temperature > tz->last_temperature) > > + trend =3D THERMAL_TREND_RAISING; > > + else if (tz->temperature < tz->last_temperature) > > + trend =3D THERMAL_TREND_DROPPING; > > + else > > + trend =3D THERMAL_TREND_STABLE; > > + } > > + > > /* > > * Above Trip? > > * ----------- > > @@ -1091,6 +1105,9 @@ void thermal_zone_device_update(struct therma= l_zone_device *tz) > > goto leave; > > } > > =20 > > + tz->last_temperature =3D tz->temperature; > > + tz->temperature =3D temp; > > + > > for (count =3D 0; count < tz->trips; count++) { > > tz->ops->get_trip_type(tz, count, &trip_type); > > tz->ops->get_trip_temp(tz, count, &trip_temp); > > @@ -1150,8 +1167,6 @@ void thermal_zone_device_update(struct therma= l_zone_device *tz) > > thermal_zone_device_passive(tz, temp, tz->forced_passive, > > THERMAL_TRIPS_NONE); > > =20 > > - tz->last_temperature =3D temp; > > - > > leave: > > if (tz->passive) > > thermal_zone_device_set_polling(tz, tz->passive_delay); > > diff --git a/include/linux/thermal.h b/include/linux/thermal.h > > index a43b12c..a01e3e6 100644 > > --- a/include/linux/thermal.h > > +++ b/include/linux/thermal.h > > @@ -44,6 +44,12 @@ enum thermal_trip_type { > > THERMAL_TRIP_CRITICAL, > > }; > > =20 > > +enum thermal_trend { > > + THERMAL_TREND_STABLE, /* temperature is stable */ > > + THERMAL_TREND_RAISING, /* temperature is raising */ > > + THERMAL_TREND_DROPPING, /* temperature is dropping */ > > +}; > > + > > struct thermal_zone_device_ops { > > int (*bind) (struct thermal_zone_device *, > > struct thermal_cooling_device *); > > @@ -65,6 +71,8 @@ struct thermal_zone_device_ops { > > int (*set_trip_hyst) (struct thermal_zone_device *, int, > > unsigned long); > > int (*get_crit_temp) (struct thermal_zone_device *, unsigned long= *); > > + int (*get_trend) (struct thermal_zone_device *, int, > > + enum thermal_trend *); > > int (*notify) (struct thermal_zone_device *, int, > > enum thermal_trip_type); > > }; > > @@ -111,6 +119,7 @@ struct thermal_zone_device { > > int tc2; > > int passive_delay; > > int polling_delay; > > + int temperature; > > int last_temperature; > > bool passive; > > unsigned int forced_passive; > >=20 >=20 -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html