From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751687AbcFVDQQ (ORCPT ); Tue, 21 Jun 2016 23:16:16 -0400 Received: from mga11.intel.com ([192.55.52.93]:56687 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751287AbcFVDQN (ORCPT ); Tue, 21 Jun 2016 23:16:13 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.26,508,1459839600"; d="scan'208";a="992589860" Message-ID: <1466565319.2379.0.camel@intel.com> Subject: Re: [PATCH v5 1/5] thermal: Add support for hardware-tracked trip points From: Zhang Rui To: Caesar Wang , edubezval@gmail.com, linux-pm@vger.kernel.org Cc: 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, javi.merino@arm.com, peter@piie.net, Sascha Hauer , Jonathan Corbet , Andy Champ , Laxman Dewangan , Durgadoss R , Ni Wade , Leo Yan , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org Date: Wed, 22 Jun 2016 11:15:19 +0800 In-Reply-To: <1465213489-14898-2-git-send-email-wxt@rock-chips.com> References: <1465213489-14898-1-git-send-email-wxt@rock-chips.com> <1465213489-14898-2-git-send-email-wxt@rock-chips.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.18.5.2-0ubuntu3 Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 一, 2016-06-06 at 19:44 +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 v5: > - add the lock for thermal_zone_set_trips function. > - change based on next kernel. > > Changes in v4: > - Missing the lock added in v3. > > 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      | 54 > +++++++++++++++++++++++++++++++++++++ >  drivers/thermal/thermal_sysfs.c     |  3 +++ >  include/linux/thermal.h             | 10 +++++++ >  4 files changed, 74 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 792aab7..e69aee2 100644 > --- a/drivers/thermal/thermal_core.c > +++ b/drivers/thermal/thermal_core.c > @@ -368,6 +368,56 @@ static void handle_thermal_trip(struct > thermal_zone_device *tz, int trip) >   monitor_thermal_zone(tz); >  } >   > +void thermal_zone_set_trips(struct thermal_zone_device *tz) > +{ > + int low = -INT_MAX; > + int high = INT_MAX; > + int trip_temp, hysteresis; > + int i, ret; > + > + mutex_lock(&tz->lock); > + > + if (!tz->ops->set_trips) > + goto exit; > + if (!tz->ops->get_trip_hyst) goto exit; otherwise, the patch looks good to me. thanks, rui > + 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 < tz->temperature && trip_low > low) > + low = trip_low; > + > + if (trip_temp > tz->temperature && trip_temp < high) > + high = trip_temp; > + } > + > + /* No need to change trip points */ > + if (tz->prev_low_trip == low && tz->prev_high_trip == high) > + goto exit; > + > + 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); > + > +exit: > + mutex_unlock(&tz->lock); > +} > +EXPORT_SYMBOL_GPL(thermal_zone_set_trips); > + >  static void update_temperature(struct thermal_zone_device *tz) >  { >   int temp, ret; > @@ -417,6 +467,8 @@ void thermal_zone_device_update(struct > thermal_zone_device *tz) >   >   update_temperature(tz); >   > + thermal_zone_set_trips(tz); > + >   for (count = 0; count < tz->trips; count++) >   handle_thermal_trip(tz, count); >  } > @@ -1175,6 +1227,8 @@ thermal_zone_device_register(const char *type, > int trips, int mask, >   tz->trips = trips; >   tz->passive_delay = passive_delay; >   tz->polling_delay = polling_delay; > + tz->prev_low_trip = INT_MAX; > + tz->prev_high_trip = -INT_MAX; >   >   /* sys I/F */ >   /* Add nodes that are always present via .groups */ > diff --git a/drivers/thermal/thermal_sysfs.c > b/drivers/thermal/thermal_sysfs.c > index 743df50..33bbe30 100644 > --- a/drivers/thermal/thermal_sysfs.c > +++ b/drivers/thermal/thermal_sysfs.c > @@ -219,6 +219,9 @@ trip_point_hyst_store(struct device *dev, struct > device_attribute *attr, >   ret = tz->ops->set_trip_hyst(tz, trip, temperature); >   mutex_unlock(&tz->lock); >   > + if (!ret) > + thermal_zone_set_trips(tz); > + >   return ret ? ret : count; >  } >   > diff --git a/include/linux/thermal.h b/include/linux/thermal.h > index ea667b6..780e69d 100644 > --- a/include/linux/thermal.h > +++ b/include/linux/thermal.h > @@ -99,6 +99,7 @@ struct thermal_zone_device_ops { >   int (*unbind) (struct thermal_zone_device *, >          struct thermal_cooling_device *); >   int (*get_temp) (struct thermal_zone_device *, int *); > + int (*set_trips) (struct thermal_zone_device *, int, int); >   int (*get_mode) (struct thermal_zone_device *, >    enum thermal_device_mode *); >   int (*set_mode) (struct thermal_zone_device *, > @@ -169,6 +170,10 @@ struct thermal_attr { >   * @last_temperature: previous temperature read >   * @emul_temperature: emulated temperature when using > CONFIG_THERMAL_EMULATION >   * @passive: 1 if you've crossed a passive trip > point, 0 otherwise. > + * @prev_low_trip: the low current temperature if you've > crossed a passive > + trip point. > + * @prev_high_trip: the above current temperature if you've > crossed a > + passive trip point. >   * @forced_passive: If > 0, temperature at which to switch on > all ACPI >   * processor cooling devices.  Currently only > used by the >   * step-wise governor. > @@ -201,6 +206,8 @@ struct thermal_zone_device { >   int last_temperature; >   int emul_temperature; >   int passive; > + int prev_low_trip; > + int prev_high_trip; >   unsigned int forced_passive; >   atomic_t need_update; >   struct thermal_zone_device_ops *ops; > @@ -428,6 +435,7 @@ int thermal_zone_bind_cooling_device(struct > thermal_zone_device *, int, >  int thermal_zone_unbind_cooling_device(struct thermal_zone_device *, > int, >          struct thermal_cooling_device > *); >  void thermal_zone_device_update(struct thermal_zone_device *); > +void thermal_zone_set_trips(struct thermal_zone_device *); >   >  struct thermal_cooling_device *thermal_cooling_device_register(char > *, void *, >   const struct thermal_cooling_device_ops *); > @@ -477,6 +485,8 @@ static inline int > thermal_zone_unbind_cooling_device( >  { return -ENODEV; } >  static inline void thermal_zone_device_update(struct > thermal_zone_device *tz) >  { } > +static inline void thermal_zone_set_trips(struct thermal_zone_device > *tz) > +{ } >  static inline struct thermal_cooling_device * >  thermal_cooling_device_register(char *type, void *devdata, >   const struct thermal_cooling_device_ops *ops)