Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753045AbbDGCkW (ORCPT ); Mon, 6 Apr 2015 22:40:22 -0400 Received: from mail-pd0-f172.google.com ([209.85.192.172]:36018 "EHLO mail-pd0-f172.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752884AbbDGCkU (ORCPT ); Mon, 6 Apr 2015 22:40:20 -0400 Date: Mon, 6 Apr 2015 19:40:28 -0700 From: Eduardo Valentin To: Sascha Hauer Cc: linux-pm@vger.kernel.org, Zhang Rui , linux-kernel@vger.kernel.org, Stephen Warren , Mikko Perttunen , kernel@pengutronix.de, linux-mediatek@lists.infradead.org, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH 12/13] thermal: Add support for hardware-tracked trip points Message-ID: <20150407024027.GG4648@localhost.localdomain> References: <1427385240-6086-1-git-send-email-s.hauer@pengutronix.de> <1427385240-6086-13-git-send-email-s.hauer@pengutronix.de> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="9/eUdp+dLtKXvemk" Content-Disposition: inline In-Reply-To: <1427385240-6086-13-git-send-email-s.hauer@pengutronix.de> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5104 Lines: 149 --9/eUdp+dLtKXvemk Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable 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. >=20 > 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. >=20 > If .set_trips is not implemented, the framework behaves as before. >=20 > This patch is based on an earlier version from Mikko Perttunen > >=20 > Signed-off-by: Sascha Hauer > --- > drivers/thermal/thermal_core.c | 41 ++++++++++++++++++++++++++++++++++++= +++++ > include/linux/thermal.h | 3 +++ > 2 files changed, 44 insertions(+) >=20 > diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_cor= e.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); > =20 > +static void thermal_zone_set_trips(struct thermal_zone_device *tz) > +{ > + unsigned long low =3D 0; > + unsigned long high =3D ULONG_MAX; > + unsigned long trip_temp, hysteresis; > + unsigned long temp =3D 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 =3D 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 =3D trip_temp - hysteresis; > + > + if (trip_low < temp && trip_low > low) > + low =3D trip_low; > + > + if (trip_temp > temp && trip_temp < high) > + high =3D trip_temp; > + } > + > + tz->prev_low_trip =3D low; > + tz->prev_high_trip =3D 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_d= evice *tz) > dev_dbg(&tz->device, "last_temperature=3D%lu, current_temperature=3D%lu= \n", > tz->last_temperature, tz->temperature); > =20 > + 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 =3D 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; > --=20 > 2.1.4 >=20 --9/eUdp+dLtKXvemk Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) iQEcBAEBAgAGBQJVI0OXAAoJEMLUO4d9pOJWl4UH/0sK7HEA1M6SkZYyb1nTiyJM hu3WltO7xC8/nwej2OsLfh5G/zmwvqWNGUYPxbQrmgpJPSvE+DOAyuHXRLY/lCt2 FH9aNFTtIfNn6WhmsMBSy3rFVxCkZ8BNVZSZPHelKOXiQLDDpBWtnZ08F0rPT5wH U/AZmKb2lNJj3iqQ+7DsPY7O96mkmq0QsCb6p7NFzXGakfWfODJswjBuGmJa9RTt YTr/B07+/ou9uoQMi/ehfy5SS/UEJmZNsTatvpvTwU2nI7fTxxiBWmJClS2Zxfas OoV7UbRGEBCI9gNpo3eXTcnmmo0z4erhbi4C82kjm+ViYBxFujrTXA5QetFgppo= =vY1O -----END PGP SIGNATURE----- --9/eUdp+dLtKXvemk-- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/