Re: [PATCH 00/17] thermal: enable/check sensor after its setup is finished

From: Eduardo Valentin
Date: Mon Sep 10 2018 - 13:37:12 EST


On Tue, Apr 10, 2018 at 02:41:54PM +0200, Bartlomiej Zolnierkiewicz wrote:
> Hi,
>
> [devm]_thermal_zone_of_sensor_register() is used to register
> thermal sensor by thermal drivers using DeviceTree. Besides
> registering sensor this function also immediately enables it
> (using ->set_mode method) and then checks it with a update call
> to the thermal core (which ends up using ->get_temp method).

Yeah, pretty much the driver needs to be ready to answer to callbacks
once it calls thermal_*_register() method.

> For many DT thermal drivers this causes a problem because

Can you be more specific? Are you seeing this problem in samsung driver
or in other drivers too?

> [devm]_thermal_zone_of_sensor_register() need to be called in
> order to obtain data about thermal trips which are then used to
> finish hardware sensor setup (only after which ->get_temp can
> be used). The issue has been observed when using Samsung Exynos

Oh I see, this is because trip info is read by the of thermal thermal
then, correct?

> thermal driver and fixed internally in the driver in commit
> d8efad71e5b6 ("thermal: exynos: Reading temperature makes sense
> only when TMU is turned on"). However after this commit there
> are now following warnings from the thermal core visible:
>
> [ 3.453602] thermal thermal_zone0: failed to read out thermal zone (-22)
> [ 3.483468] thermal thermal_zone1: failed to read out thermal zone (-22)
> [ 3.505965] thermal thermal_zone2: failed to read out thermal zone (-22)
> [ 3.528455] thermal thermal_zone3: failed to read out thermal zone (-22)
> [ 3.550939] thermal thermal_zone4: failed to read out thermal zone (-22)
>
> This patchset attempts to directly address the thermal core
> problem with [devm]_thermal_zone_of_sensor_register() and
> affected DT thermal drivers. In order to achieve this sensor
> registration, enable and check operations are separated and
> corresponding drivers are modified to use the new helpers to
> enable and check sensor explicitly.
>

Ok. Up to this point I followed that this is a samsung driver issue, not
we need to change the core to fix adapt to it?

And adapting the core should be fine to fit a new use/fix something,
as long the issue is well described..

> Tested on Exynos5422 based Odroid-XU3 Lite board (aforementioned
> warnings from the thermal core are now gone).
>
> Best regards,
> --
> Bartlomiej Zolnierkiewicz
> Samsung R&D Institute Poland
> Samsung Electronics
>
>
> Bartlomiej Zolnierkiewicz (17):
> thermal: add thermal_zone_device_toggle() helper
> thermal: separate sensor registration and enable
> thermal: add thermal_zone_device_check() helper
> thermal: do sensor checking explicitly in drivers
> thermal: bcm2835: enable/check sensor after its setup is finished
> thermal: brcmstb: enable/check sensor after its setup is finished
> thermal: hisi_thermal: enable/check sensor after its setup is finished
> thermal: qcom: tsens: enable/check sensor after its setup is finished
> thermal: qoriq: enable/check sensor after its setup is finished
> thermal: rcar_gen3_thermal: enable/check sensor after its setup is
> finished
> thermal: rockchip_thermal: enable/check sensor after its setup is
> finished
> thermal: exynos: enable/check sensor after its setup is finished
> thermal: tegra: enable/check sensor after its setup is finished
> thermal: ti-soc-thermal: enable/check sensor after its setup is
> finished
> thermal: uniphier: enable/check sensor after its setup is
> finished
> thermal: zx2967: enable/check sensor after its setup is finished
> thermal: warn on attempts to read temperature on disabled sensors
>
> drivers/acpi/thermal.c | 5 ++--
> drivers/net/ethernet/mellanox/mlxsw/core_thermal.c | 1 -
> drivers/platform/x86/acerhdf.c | 6 +++-
> drivers/regulator/max8973-regulator.c | 3 +-
> drivers/thermal/broadcom/bcm2835_thermal.c | 3 ++
> drivers/thermal/broadcom/brcmstb_thermal.c | 3 ++
> drivers/thermal/broadcom/ns-thermal.c | 3 ++
> drivers/thermal/da9062-thermal.c | 7 ++---
> drivers/thermal/db8500_thermal.c | 5 +++-
> drivers/thermal/hisi_thermal.c | 22 ++++----------
> drivers/thermal/imx_thermal.c | 3 +-
> drivers/thermal/int340x_thermal/int3400_thermal.c | 1 +
> drivers/thermal/intel_bxt_pmic_thermal.c | 3 +-
> drivers/thermal/intel_soc_dts_iosf.c | 3 +-
> drivers/thermal/max77620_thermal.c | 6 ++--
> drivers/thermal/mtk_thermal.c | 3 ++
> drivers/thermal/of-thermal.c | 6 ++--
> drivers/thermal/qcom-spmi-temp-alarm.c | 5 +++-
> drivers/thermal/qcom/tsens.c | 6 ++++
> drivers/thermal/qoriq_thermal.c | 3 ++
> drivers/thermal/rcar_gen3_thermal.c | 7 +++--
> drivers/thermal/rcar_thermal.c | 8 +++--
> drivers/thermal/rockchip_thermal.c | 34 ++++++++++------------
> drivers/thermal/samsung/exynos_tmu.c | 7 ++++-
> drivers/thermal/st/st_thermal_memmap.c | 3 +-
> drivers/thermal/tango_thermal.c | 5 ++++
> drivers/thermal/tegra/soctherm.c | 3 ++
> drivers/thermal/tegra/tegra-bpmp-thermal.c | 3 ++
> drivers/thermal/thermal-generic-adc.c | 3 ++
> drivers/thermal/thermal_core.c | 14 ++++-----
> drivers/thermal/thermal_helpers.c | 33 +++++++++++++++++++++
> drivers/thermal/thermal_sysfs.c | 17 +++++++----
> drivers/thermal/ti-soc-thermal/ti-thermal-common.c | 7 ++++-
> drivers/thermal/uniphier_thermal.c | 6 +++-
> drivers/thermal/x86_pkg_temp_thermal.c | 2 +-
> drivers/thermal/zx2967_thermal.c | 3 ++
> include/linux/thermal.h | 5 ++++
> 37 files changed, 173 insertions(+), 84 deletions(-)
>
> --
> 1.9.1