| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Date: Wed, 25 May 2016 17:42:58 +0100
From: Javi Merino <javi.merino@....com>
To: Caesar Wang <wxt@...k-chips.com>
Cc: edubezval@...il.com, linux-pm@...r.kernel.org,
Heiko Stuebner <heiko@...ech.de>, dianders@...omium.org,
briannorris@...gle.com, smbarber@...gle.com,
linux-rockchip@...ts.infradead.org, cf@...k-chips.com,
huangtao@...k-chips.com, dmitry.torokhov@...il.com, peter@...e.net,
Sascha Hauer <s.hauer@...gutronix.de>,
Zhang Rui <rui.zhang@...el.com>,
Jonathan Corbet <corbet@....net>,
Laxman Dewangan <ldewangan@...dia.com>,
Leo Yan <leo.yan@...aro.org>, Ni Wade <wni@...dia.com>,
Andy Champ <andycham@...zon.com>, linux-doc@...r.kernel.org,
linux-kernel@...r.kernel.org
Subject: Re: [PATCH v3 1/5] thermal: Add support for hardware-tracked trip
points
Hi Caesar,
On Wed, May 25, 2016 at 11:47:45AM +0800, Caesar Wang wrote:
> From: Sascha Hauer <s.hauer@...gutronix.de>
>
> 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
> <mikko.perttunen@...si.fi>
>
> Signed-off-by: Sascha Hauer <s.hauer@...gutronix.de>
> Signed-off-by: Caesar Wang <wxt@...k-chips.com>
> Cc: Zhang Rui <rui.zhang@...el.com>
> Cc: Eduardo Valentin <edubezval@...il.com>
> Cc: linux-pm@...r.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
Powered by blists - more mailing lists