linux-stable.git/drivers/thermal, branch v6.6.2

thermal: core: Don't update trip points inside the hysteresis range

2023-11-20T10:59:01+00:00

[ Upstream commit cf3986f8c01d355490d0ac6024391b989a9d1e9d ]

When searching for the trip points that need to be set, the nearest
higher trip point's temperature is used for the high trip, while the
nearest lower trip point's temperature minus the hysteresis is used for
the low trip. The issue with this logic is that when the current
temperature is inside a trip point's hysteresis range, both high and low
trips will come from the same trip point. As a consequence instability
can still occur like this:
* the temperature rises slightly and enters the hysteresis range of a
  trip point
* polling happens and updates the trip points to the hysteresis range
* the temperature falls slightly, exiting the hysteresis range, crossing
  the trip point and triggering an IRQ, the trip points are updated
* repeat

So even though the current hysteresis implementation prevents
instability from happening due to IRQs triggering on the same
temperature value, both ways, it doesn't prevent it from happening due
to an IRQ on one way and polling on the other.

To properly implement a hysteresis behavior, when inside the hysteresis
range, don't update the trip points. This way, the previously set trip
points will stay in effect, which will in a way remember the previous
state (if the temperature signal came from above or below the range) and
therefore have the right trip point already set.

The exception is if there was no previous trip point set, in which case
a previous state doesn't exist, and so it's sensible to allow the
hysteresis range as trip points.

The following logs show the current behavior when running on a real
machine:

[  202.524658] thermal thermal_zone0: new temperature boundaries: -2147483647 < x < 40000
   203.562817: thermal_temperature: thermal_zone=vpu0-thermal id=0 temp_prev=36986 temp=37979
[  203.562845] thermal thermal_zone0: new temperature boundaries: 37000 < x < 40000
   204.176059: thermal_temperature: thermal_zone=vpu0-thermal id=0 temp_prev=37979 temp=40028
[  204.176089] thermal thermal_zone0: new temperature boundaries: 37000 < x < 100000
   205.226813: thermal_temperature: thermal_zone=vpu0-thermal id=0 temp_prev=40028 temp=38652
[  205.226842] thermal thermal_zone0: new temperature boundaries: 37000 < x < 40000

And with this patch applied:

[  184.933415] thermal thermal_zone0: new temperature boundaries: -2147483647 < x < 40000
   185.981182: thermal_temperature: thermal_zone=vpu0-thermal id=0 temp_prev=36986 temp=37872
   186.744685: thermal_temperature: thermal_zone=vpu0-thermal id=0 temp_prev=37872 temp=40058
[  186.744716] thermal thermal_zone0: new temperature boundaries: 37000 < x < 100000
   187.773284: thermal_temperature: thermal_zone=vpu0-thermal id=0 temp_prev=40058 temp=38698

Fixes: 060c034a9741 ("thermal: Add support for hardware-tracked trip points")
Signed-off-by: Nícolas F. R. A. Prado 
Reviewed-by: AngeloGioacchino Del Regno 
Co-developed-by: Rafael J. Wysocki 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Sasha Levin

thermal/drivers/mediatek: Fix probe for THERMAL_V2

2023-11-20T10:59:01+00:00

[ Upstream commit 5055fadfa7e16f2427d5b3c40b2bf563ddfdab22 ]

Fix the probe function to call mtk_thermal_release_periodic_ts for
everything != MTK_THERMAL_V1. This was accidentally changed from V1
to V2 in the original patch.

Reported-by: Frank Wunderlich 
Closes: https://lore.kernel.org/lkml/B0B3775B-B8D1-4284-814F-4F41EC22F532@public-files.de/
Reported-by: Daniel Lezcano 
Closes: https://lore.kernel.org/lkml/07a569b9-e691-64ea-dd65-3b49842af33d@linaro.org/
Fixes: 33140e668b10 ("thermal/drivers/mediatek: Control buffer enablement tweaks")
Signed-off-by: Markus Schneider-Pargmann 
Reviewed-by: AngeloGioacchino Del Regno 
Signed-off-by: Daniel Lezcano 
Link: https://lore.kernel.org/r/20230918100706.1229239-1-msp@baylibre.com
Signed-off-by: Sasha Levin

thermal: core: prevent potential string overflow

2023-11-20T10:59:01+00:00

[ Upstream commit c99626092efca3061b387043d4a7399bf75fbdd5 ]

The dev->id value comes from ida_alloc() so it's a number between zero
and INT_MAX.  If it's too high then these sprintf()s will overflow.

Fixes: 203d3d4aa482 ("the generic thermal sysfs driver")
Signed-off-by: Dan Carpenter 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Sasha Levin

thermal: sysfs: Fix trip_point_hyst_store()

2023-09-18T11:13:05+00:00

After commit 2e38a2a981b2 ("thermal/core: Add a generic thermal_zone_set_trip()
function") updating a trip point temperature doesn't actually work,
because the value supplied by user space is subsequently overwritten
with the current trip point hysteresis value.

Fix this by changing the code to parse the number string supplied by
user space after retrieving the current trip point data from the
thermal zone.

Also drop a redundant tab character from the code in question.

Fixes: 2e38a2a981b2 ("thermal/core: Add a generic thermal_zone_set_trip() function")
Signed-off-by: Rafael J. Wysocki 
Cc: 6.3+  # 6.3+

thermal: core: Fix disabled trip point check in handle_thermal_trip()

2023-09-14T19:51:49+00:00

Commit bc840ea5f9a9 ("thermal: core: Do not handle trip points with
invalid temperature") added a check for invalid temperature to the
disabled trip point check in handle_thermal_trip(), but that check was
added at a point when the trip structure has not been initialized yet.

This may cause handle_thermal_trip() to skip a valid trip point in some
cases, so fix it by moving the check to a suitable place, after
__thermal_zone_get_trip() has been called to populate the trip
structure.

Fixes: bc840ea5f9a9 ("thermal: core: Do not handle trip points with invalid temperature")
Signed-off-by: Rafael J. Wysocki

thermal: Constify the trip argument of the .get_trend() zone callback

2023-09-11T15:16:40+00:00

Add 'const' to the definition of the 'trip' argument of the
.get_trend() thermal zone callback to indicate that the trip point
passed to it should not be modified by it and adjust the
callback functions implementing it, thermal_get_trend() in the
ACPI thermal driver and __ti_thermal_get_trend(), accordingly.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki 
Reviewed-by: Michal Wilczynski

thermal/of: add missing of_node_put()

2023-09-11T15:16:36+00:00

for_each_child_of_node performs an of_node_get on each
iteration, so a break out of the loop requires an
of_node_put.

This was done using the Coccinelle semantic patch
iterators/for_each_child.cocci

Signed-off-by: Julia Lawall 
Signed-off-by: Rafael J. Wysocki

thermal: core: Drop thermal_zone_device_register()

2023-09-05T19:42:18+00:00

There are no more users of thermal_zone_device_register(), so drop it
from the core.

Note that thermal_zone_device_register_with_trips() may be renamed to
thermal_zone_device_register() in the future, but only after a grace
period allowing all of the possible work in progress that may be using
the latter to adjust.

Signed-off-by: Rafael J. Wysocki

thermal: Use thermal_tripless_zone_device_register()

2023-09-05T19:42:18+00:00

All of the remaining callers of thermal_zone_device_register()
can use thermal_tripless_zone_device_register(), so make them
do so in order to allow the former to be dropped.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki 
Acked-by: Miquel Raynal

thermal: core: Add function for registering tripless thermal zones

2023-09-05T19:42:18+00:00

Multiple callers of thermal_zone_device_register() don't pass any trips
to it and they might use a shortened argument list for that, so add
a special function with fewer arguments for this purpose.

Signed-off-by: Rafael J. Wysocki