Introduce and use hwmon_update_groups() to support changing sysfs
attribute visibility dynamically without having to re-register
affected hardware monitoring devices.

Use the new function in the ACPI power meter driver.

RFT: The new function was tested extensively with a dummy driver
which changes attribute visibility every few seconds. However,
it was not tested in the 'real world'.

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Guenter Roeck (5):
      hwmon: Handle attribute visibility evaluation in device core
      hwmon: Provide helper function to find thermal zones
      hwmon: Add support for updating thermal zones
      hwmon: Implement hwmon_update_groups()
      hwmon: (acpi_power_meter) Use hwmon_update_groups() to update sensor visibility

 Documentation/hwmon/hwmon-kernel-api.rst |   8 +++
 drivers/hwmon/acpi_power_meter.c         |  37 ++++-------
 drivers/hwmon/hwmon.c                    | 108 ++++++++++++++++++++++++-------
 include/linux/hwmon.h                    |   2 +
 4 files changed, 109 insertions(+), 46 deletions(-)