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

[Bartlomiej Zolnierkiewicz]

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(-)

-- 
1.9.1