From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753692Ab2KHGBz (ORCPT ); Thu, 8 Nov 2012 01:01:55 -0500 Received: from mga09.intel.com ([134.134.136.24]:2403 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750881Ab2KHGBx (ORCPT ); Thu, 8 Nov 2012 01:01:53 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.80,736,1344236400"; d="scan'208";a="216658718" Message-ID: <1352354503.2190.7.camel@rzhang1-mobl4> Subject: Re: [PATCH 1/4] thermal: Add new thermal trend type to support quick cooling From: Zhang Rui To: Amit Daniel Kachhap Cc: linux-pm@lists.linux-foundation.org, linux-samsung-soc@vger.kernel.org, linux-kernel@vger.kernel.org, durgadoss.r@intel.com, lenb@kernel.org, linux-acpi@vger.kernel.org, jonghwa3.lee@samsung.com Date: Thu, 08 Nov 2012 14:01:43 +0800 In-Reply-To: <1352348786-24255-2-git-send-email-amit.kachhap@linaro.org> References: <1352348786-24255-1-git-send-email-amit.kachhap@linaro.org> <1352348786-24255-2-git-send-email-amit.kachhap@linaro.org> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.2.3-0ubuntu6 Content-Transfer-Encoding: 7bit Mime-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 2012-11-08 at 09:56 +0530, Amit Daniel Kachhap wrote: > This modification adds 2 new thermal trend type THERMAL_TREND_RAISE_FULL > and THERMAL_TREND_DROP_FULL. This thermal trend can be used to quickly > jump to the upper or lower cooling level instead of incremental increase > or decrease. IMO, what we need is a new more aggressive cooling governor which always uses upper limit when the temperature is raising and lower limit when the temperature is dropping. I can write such a governor if you do not have time to. thanks, rui > This is needed for temperature sensors which support rising/falling > threshold interrupts and polling can be totally avoided. > > Signed-off-by: Amit Daniel Kachhap > Signed-off-by: Amit Daniel Kachhap > --- > drivers/thermal/step_wise.c | 19 +++++++++++++++---- > include/linux/thermal.h | 2 ++ > 2 files changed, 17 insertions(+), 4 deletions(-) > > diff --git a/drivers/thermal/step_wise.c b/drivers/thermal/step_wise.c > index 1242cff..0d2d8d6 100644 > --- a/drivers/thermal/step_wise.c > +++ b/drivers/thermal/step_wise.c > @@ -35,6 +35,10 @@ > * state for this trip point > * b. if the trend is THERMAL_TREND_DROPPING, use lower cooling > * state for this trip point > + * c. if the trend is THERMAL_TREND_RAISE_FULL, use highest cooling > + * state for this trip point > + * d. if the trend is THERMAL_TREND_DROP_FULL, use lowest cooling > + * state for this trip point > */ > static unsigned long get_target_state(struct thermal_instance *instance, > enum thermal_trend trend) > @@ -50,7 +54,10 @@ static unsigned long get_target_state(struct thermal_instance *instance, > } else if (trend == THERMAL_TREND_DROPPING) { > cur_state = cur_state > instance->lower ? > (cur_state - 1) : instance->lower; > - } > + } else if (trend == THERMAL_TREND_RAISE_FULL) > + cur_state = instance->upper; > + else if (trend == THERMAL_TREND_DROP_FULL) > + cur_state = instance->lower; > > return cur_state; > } > @@ -87,7 +94,8 @@ static void update_instance_for_throttle(struct thermal_zone_device *tz, > } > > static void update_instance_for_dethrottle(struct thermal_zone_device *tz, > - int trip, enum thermal_trip_type trip_type) > + int trip, enum thermal_trip_type trip_type, > + enum thermal_trend trend) > { > struct thermal_instance *instance; > struct thermal_cooling_device *cdev; > @@ -101,7 +109,10 @@ static void update_instance_for_dethrottle(struct thermal_zone_device *tz, > cdev = instance->cdev; > cdev->ops->get_cur_state(cdev, &cur_state); > > - instance->target = cur_state > instance->lower ? > + if (trend == THERMAL_TREND_DROP_FULL) > + instance->target = instance->lower; > + else > + instance->target = cur_state > instance->lower ? > (cur_state - 1) : THERMAL_NO_TARGET; > > /* Deactivate a passive thermal instance */ > @@ -133,7 +144,7 @@ static void thermal_zone_trip_update(struct thermal_zone_device *tz, int trip) > if (tz->temperature >= trip_temp) > update_instance_for_throttle(tz, trip, trip_type, trend); > else > - update_instance_for_dethrottle(tz, trip, trip_type); > + update_instance_for_dethrottle(tz, trip, trip_type, trend); > > mutex_unlock(&tz->lock); > } > diff --git a/include/linux/thermal.h b/include/linux/thermal.h > index 807f214..8bce3ec 100644 > --- a/include/linux/thermal.h > +++ b/include/linux/thermal.h > @@ -68,6 +68,8 @@ enum thermal_trend { > THERMAL_TREND_STABLE, /* temperature is stable */ > THERMAL_TREND_RAISING, /* temperature is raising */ > THERMAL_TREND_DROPPING, /* temperature is dropping */ > + THERMAL_TREND_RAISE_FULL, /* Apply highest cooling action*/ > + THERMAL_TREND_DROP_FULL, /* Apply lowest cooling action*/ > }; > > /* Events supported by Thermal Netlink */