From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753137AbbCZP4K (ORCPT ); Thu, 26 Mar 2015 11:56:10 -0400 Received: from metis.ext.pengutronix.de ([92.198.50.35]:56427 "EHLO metis.ext.pengutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753012AbbCZPyR (ORCPT ); Thu, 26 Mar 2015 11:54:17 -0400 From: Sascha Hauer To: linux-pm@vger.kernel.org Cc: Zhang Rui , Eduardo Valentin , linux-kernel@vger.kernel.org, Stephen Warren , Mikko Perttunen , kernel@pengutronix.de, linux-mediatek@lists.infradead.org, linux-arm-kernel@lists.infradead.org, Sascha Hauer Subject: [PATCH 12/13] thermal: Add support for hardware-tracked trip points Date: Thu, 26 Mar 2015 16:53:59 +0100 Message-Id: <1427385240-6086-13-git-send-email-s.hauer@pengutronix.de> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1427385240-6086-1-git-send-email-s.hauer@pengutronix.de> References: <1427385240-6086-1-git-send-email-s.hauer@pengutronix.de> X-SA-Exim-Connect-IP: 2001:67c:670:100:1d::7 X-SA-Exim-Mail-From: sha@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-kernel@vger.kernel.org Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 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. 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 --- drivers/thermal/thermal_core.c | 41 +++++++++++++++++++++++++++++++++++++++++ include/linux/thermal.h | 3 +++ 2 files changed, 44 insertions(+) diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.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); +static void thermal_zone_set_trips(struct thermal_zone_device *tz) +{ + unsigned long low = 0; + unsigned long high = ULONG_MAX; + unsigned long trip_temp, hysteresis; + unsigned long temp = 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 = 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 = trip_temp - hysteresis; + + if (trip_low < temp && trip_low > low) + low = trip_low; + + if (trip_temp > temp && trip_temp < high) + high = trip_temp; + } + + tz->prev_low_trip = low; + tz->prev_high_trip = 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_device *tz) dev_dbg(&tz->device, "last_temperature=%lu, current_temperature=%lu\n", tz->last_temperature, tz->temperature); + thermal_zone_set_trips(tz); + for (count = 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; -- 2.1.4 From mboxrd@z Thu Jan 1 00:00:00 1970 From: s.hauer@pengutronix.de (Sascha Hauer) Date: Thu, 26 Mar 2015 16:53:59 +0100 Subject: [PATCH 12/13] thermal: Add support for hardware-tracked trip points In-Reply-To: <1427385240-6086-1-git-send-email-s.hauer@pengutronix.de> References: <1427385240-6086-1-git-send-email-s.hauer@pengutronix.de> Message-ID: <1427385240-6086-13-git-send-email-s.hauer@pengutronix.de> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org 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 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. 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 --- drivers/thermal/thermal_core.c | 41 +++++++++++++++++++++++++++++++++++++++++ include/linux/thermal.h | 3 +++ 2 files changed, 44 insertions(+) diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.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); +static void thermal_zone_set_trips(struct thermal_zone_device *tz) +{ + unsigned long low = 0; + unsigned long high = ULONG_MAX; + unsigned long trip_temp, hysteresis; + unsigned long temp = 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 = 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 = trip_temp - hysteresis; + + if (trip_low < temp && trip_low > low) + low = trip_low; + + if (trip_temp > temp && trip_temp < high) + high = trip_temp; + } + + tz->prev_low_trip = low; + tz->prev_high_trip = 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_device *tz) dev_dbg(&tz->device, "last_temperature=%lu, current_temperature=%lu\n", tz->last_temperature, tz->temperature); + thermal_zone_set_trips(tz); + for (count = 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; -- 2.1.4