Re: [PATCH v2 00/17] thermal: enable+check sensor after its setup is finished

From: Eduardo Valentin
Date: Mon Nov 05 2018 - 19:46:55 EST

Hey,

On Mon, Nov 05, 2018 at 05:35:55PM +0100, Bartlomiej Zolnierkiewicz wrote:
>
> On 11/05/2018 04:04 AM, Zhang Rui wrote:
> > Hi, Bartlomiej,
>
> Hi Rui,
>
> > Interesting, I'm about to bring this issue to Linux Plumber Conference
> > this year for discussion, and I'm also proposing a solution to fix the
> > issues, but only with thermal core part finished yet.
> > can you please take a look at it?
> > https://patchwork.kernel.org/project/linux-pm/list/?series=38181
>
> Thank you for the patches but they seem to be far from being
> a complete solution for issues fixed by my patchset. Even
> thermal core part is not finished yet as it doesn't provide
> a way to register disabled sensors for DT thermal drivers (only
> for platform ones)..
>
> Why not simply apply my patchset now and incrementally work
> on top of it to implement fixes for issues your patchset is
> addressing?
>
> My patchset may not be a perfect solution but IMO it is good
> enough and it has been practically ready since v1 posted in
> April (v2 fixes all issues requested by Eduardo's review from
> September)..

Rui, I agree with Bartlomiej here. I propose to create
a topic branch with both series, Bartlomiej's then yours.

Feels to me that this is a wider change across multiple drivers,
and across driver types, platform and of- based, so might be
better to avoid breakage.



>
> > thanks,
> > rui
> >
> > On ä, 2018-10-17 at 17:52 +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:
> >>
> >> tzd->ops->set_mode(tzd, THERMAL_DEVICE_ENABLED)
> >> (->set_mode is set to of_thermal_set_mode() in of-thermal.c)
> >>
> >> - checks it (indirectly by using of_thermal_set_mode()):
> >>
> >> thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
> >> (which in turn ends up using ->get_temp method).
> >>
> >> For many DT thermal drivers this causes a problem because:
> >>
> >> - [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)
> >>
> >> There is also related issue for DT thermal drivers that support
> >> IRQ (i.e. exynos and rockchip ones):
> >>
> >> - sensor hardware should be enabled only after IRQ handler is
> >> requested (because otherwise we might get IRQs that we can't
> >> handle)
> >>
> >> - IRQ handler needs tzd structure which is obtained from
> >> [devm_]thermal_zone_of_sensor_register()
> >>
> >> - after [devm_]thermal_zone_of_sensor_register() call core
> >> thermal code assumes that sensor is enabled and ready to use
> >> (i.e. that IRQ handler has been requested and sensor hardware
> >> has been enabled)
> >>
> >> In order to fix all abovementioned issues sensor registration,
> >> enable and check operations are separated in the core DT thermal
> >> code and corresponding DT thermal drivers are modified to do sensor
> >> setup correctly.
> >>
> >> Changes since v1:
> >> - rebased on the current -next kernel (next-20181015)
> >> - enhanced patch descriptions and cover letter
> >> - renamed thermal_zone_device_toggler() to thermal_zone_set_mode()
> >> - converted thermal_zone_set_mode() to use enum thermal_device_mode
> >> - added CONFIG_THERMAL=n stubs for thermal_zone_set_mode() and
> >> thermal_zone_device_check()
> >> - fixed uses of [devm]_thermal_zone_of_sensor_register() outside of
> >> drivers/thermal/
> >> - changed ordering between patch #2 and #3 in order to add all
> >> needed core helpers first before fixing sensor setup code
> >> - changed ordering between patch #3 and #4 in order to simplify them
> >> - renamed patch #3 to "thermal: separate sensor enable and check
> >> operations"
> >> - renamed patch #4 to "thermal: separate sensor registration and
> >> enable+check operations"
> >>
> >> Best regards,
> >> --
> >> Bartlomiej Zolnierkiewicz
> >> Samsung R&D Institute Poland
> >> Samsung Electronics
> >>
> >>
> >> Bartlomiej Zolnierkiewicz (17):
> >> thermal: add thermal_zone_set_mode() helper
> >> thermal: add thermal_zone_device_check() helper
> >> thermal: separate sensor enable and check operations
> >> thermal: separate sensor registration and enable+check operations
> >> 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/ata/ahci_imx.c | 10 ++++--
> >> drivers/hwmon/hwmon.c | 5 +++
> >> drivers/hwmon/ntc_thermistor.c | 4 +++
> >> drivers/hwmon/scpi-hwmon.c | 4 +++
> >> drivers/iio/adc/sun4i-gpadc-iio.c | 5 +++
> >> drivers/input/touchscreen/sun4i-ts.c | 8 ++++-
> >> drivers/net/ethernet/mellanox/mlxsw/core_thermal.c | 1 -
> >> drivers/platform/x86/acerhdf.c | 6 +++-
> >> drivers/regulator/max8973-regulator.c | 6 ++--
> >> drivers/thermal/armada_thermal.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 | 7 ++--
> >> drivers/thermal/rockchip_thermal.c | 38 +++++++++++-
> >> ----------
> >> 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 | 32
> >> ++++++++++++++++++
> >> 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 | 11 +++++++
> >> 44 files changed, 220 insertions(+), 87 deletions(-)
>
> Best regards,
> --
> Bartlomiej Zolnierkiewicz
> Samsung R&D Institute Poland
> Samsung Electronics