[PATCH v4 0/2] hwmon: (pmbus) Add Delta AHE-50DC fan control module driver

Zev Weiss zev at bewilderbeest.net
Thu Dec 9 08:37:01 AEDT 2021


These patches add a hwmon pmbus driver for the integrated fan control
module in the Delta AHE-50DC Open19 power shelf.  I don't know of a
datasheet or any proper documentation for it.  It's a PMBus device,
but supports a fairly limited set of commands.  The ones it does
support have deen deduced from a combination of an existing GPL driver
in a code release from LinkedIn [0] and some manual experimentation
with i2c-tools commands.  In addition to some standard PMBus sensors
(three temperature readings, four fan speeds, and a vin voltage), it
also has a manufacturer-specific fourth temperature reading available,
which is supported via a virtual second page (the device itself is not
paged, but the driver remaps PMBUS_READ_TEMPERATURE_1 in page 1 to the
manufacturer-specific TEMPERATURE_4).

Zev Weiss

Changes since v3 [3]:
 - fixed header inclusion order
 - removed spurious select/depends Kconfig lines
 - added comment explaining PMBUS_NO_CAPABILITY
 - added command-filtering to read_word_data callback to avoid
   producing bogus sensor limits
 - updated commit message

Changes since v2 [2]:
 - converted to pmbus driver

Changes since v1 [1]:
 - fixed invalid name warning from __hwmon_device_register()

[0] https://github.com/linkedin/o19-bmc-firmware/blob/master/meta-openbmc/meta-linkedin/meta-deltapower/recipes-kernel/fancontrol-mod/files/fancontrol.c
[1] https://lore.kernel.org/linux-hwmon/20211206224419.15736-1-zev@bewilderbeest.net/
[2] https://lore.kernel.org/linux-hwmon/20211206230153.16891-1-zev@bewilderbeest.net/
[3] https://lore.kernel.org/linux-hwmon/20211207071521.543-1-zev@bewilderbeest.net/

Zev Weiss (2):
  hwmon: (pmbus) Add Delta AHE-50DC fan control module driver
  dt-bindings: add Delta AHE-50DC fan control module

 .../devicetree/bindings/trivial-devices.yaml  |   2 +
 MAINTAINERS                                   |   6 +
 drivers/hwmon/pmbus/Kconfig                   |  10 ++
 drivers/hwmon/pmbus/Makefile                  |   1 +
 drivers/hwmon/pmbus/delta-ahe50dc-fan.c       | 114 ++++++++++++++++++
 5 files changed, 133 insertions(+)
 create mode 100644 drivers/hwmon/pmbus/delta-ahe50dc-fan.c


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