From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755716AbcEYQnG (ORCPT ); Wed, 25 May 2016 12:43:06 -0400 Received: from foss.arm.com ([217.140.101.70]:36130 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751627AbcEYQnE (ORCPT ); Wed, 25 May 2016 12:43:04 -0400 Date: Wed, 25 May 2016 17:42:58 +0100 From: Javi Merino To: Caesar Wang Cc: edubezval@gmail.com, linux-pm@vger.kernel.org, Heiko Stuebner , dianders@chromium.org, briannorris@google.com, smbarber@google.com, linux-rockchip@lists.infradead.org, cf@rock-chips.com, huangtao@rock-chips.com, dmitry.torokhov@gmail.com, peter@piie.net, Sascha Hauer , Zhang Rui , Jonathan Corbet , Laxman Dewangan , Leo Yan , Ni Wade , Andy Champ , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v3 1/5] thermal: Add support for hardware-tracked trip points Message-ID: <20160525164258.GA11807@e104805> References: <1464148069-26254-1-git-send-email-wxt@rock-chips.com> <1464148069-26254-2-git-send-email-wxt@rock-chips.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <1464148069-26254-2-git-send-email-wxt@rock-chips.com> 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 Hi Caesar, On Wed, May 25, 2016 at 11:47:45AM +0800, Caesar Wang wrote: > From: Sascha Hauer > > 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 > > > Signed-off-by: Sascha Hauer > Signed-off-by: Caesar Wang > Cc: Zhang Rui > Cc: Eduardo Valentin > Cc: linux-pm@vger.kernel.org > > --- > > 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