tree a183e867d95e421b3b3e7d65175e6a413a795b52
parent db94adfda170686fdca28bcbaf7d99b440ee3597
author Matt Spinler <spinler@us.ibm.com> 1614277487 -0600
committer Brad Bishop <bradleyb@fuzziesquirrel.com> 1616703965 +0000

ibm: Add TMP401 driver to Rainier

This driver supports the TMP435 temperature sensor, which is used on 2
IBM manufactured PCIe cards, an NVME JBOF riser, and a PCIE gen 4 CXP
cable card.  The former only plugs into Rainier, and the latter into
Rainier and Everest.

The TMP435 devices on these cards are powered by slot power, controlled
by the hypervisor, and so will not be accessible until the hypervisor
has started and has turned on slot power.

Note that the sensor instances for these cards will not be in the device
tree because they are monitored by the hwmontempsensors application
which gets its configuration information from the entity-manager
application.  Entity-manager uses the 'new_device' API to instantiate
drivers, which does not need device tree entries.  In fact, if these are
in the device tree, then the new_device write will fail even though the
device driver wasn't truly bound to that instance.  As mentioned above,
because they are on slot power they cannot be probed as usual on kernel
startup.

Signed-off-by: Matt Spinler <spinler@us.ibm.com>
Change-Id: I8aab28266f4e4b492c8d1c0c256714439ef1b5cd