[WIP PATCH linux dev-5.4 0/4] KCS driver for LPC MCTP binding

Andrew Jeffery andrew at aj.id.au
Fri Mar 27 17:31:42 AEDT 2020


This is a series that cleans up a driver that we (IBM) have been using
internally for some time to expose the KCS device required by the astlpc
binding found in libmctp[1]. The driver is generally terrible, and the
userspace interface will no-longer be needed once I get to implementing
socket-based MCTP support (which we should have roughly around the same time as
practical nuclear fusion*).

We would like to apply this to the OpenBMC tree whilst _not_ upstreaming it on
the basis that its userspace API will become obsolete in the future and the
effort isn't worth the hassle, but we still need the functionality until we get
socket support. Several IBM system configurations make use of the driver as is,
and it serves to demonstrate the purpose of the astlpc binding in libmctp.

I've marked the series WIP because of the above reasons, not as indicator to
not apply it. However, please don't stare at the code too hard in case it
breaks you.


[1] https://github.com/openbmc/libmctp/blob/master/astlpc.c

* Not serious, but it feels this way.

Andrew Geissler (1):
  ARM: dts: tacoma: Add KCS node for LPC MCTP

Andrew Jeffery (2):
  misc: Add ASPEED KCS driver for MCTP purposes
  ARM: dts: witherspoon: Add KCS node for LPC MCTP

Eddie James (1):
  ARM: dts: rainier: Add KCS node for LPC MCTP

 arch/arm/boot/dts/aspeed-bmc-ibm-rainier.dts  |   8 +
 arch/arm/boot/dts/aspeed-bmc-opp-tacoma.dts   |   8 +
 .../boot/dts/aspeed-bmc-opp-witherspoon.dts   |   8 +
 drivers/misc/Kconfig                          |   7 +
 drivers/misc/Makefile                         |   1 +
 drivers/misc/mctp-lpc.c                       | 443 ++++++++++++++++++
 6 files changed, 475 insertions(+)
 create mode 100644 drivers/misc/mctp-lpc.c


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