Re: [PATCH v3 00/16] ipmi: Allow raw access to KCS devices

[Corey Minyard]

On Mon, May 10, 2021 at 03:11:57PM +0930, Andrew Jeffery wrote:
> Hello,
> 
> This is the 3rd spin of the series refactoring the keyboard-controller-style
> device drivers in the IPMI subsystem.

This is a nice set of cleanups outside of just allowing raw access.
I'll let you handle Zev's comments and a few of mine.

I almost hate to ask this, but would there be value in allowing the BT
driver to use this abstract interface?  Or maybe it would be just too
hard to get a common abstraction, more work than it's worth.  It's
surprising that more people don't want BT as it's vastly superior to
KCS.  Just a thought for now.  I guess there's SMIC, but hopefully
nobody wants that.

-corey

> 
> v2 can be found (in two parts because yay patch workflow mistakes) at:
> 
> Cover letter:
> https://lore.kernel.org/linux-arm-kernel/20210319061952.145040-1-andrew@xxxxxxxx/
> 
> Patches:
> https://lore.kernel.org/linux-arm-kernel/20210319062752.145730-1-andrew@xxxxxxxx/
> 
> Several significant changes in v3:
> 
> 1. The series is rebased onto v5.13-rc1
> 
> 2. v5.13-rc1 includes Chiawei's patches reworking the LPC devicetree bindings,
>    so they're no-longer required in the series.
> 
> 3. After some discussion with Arnd[1] and investigating the serio subsystem,
>    I've replaced the "raw" KCS driver (patch 16/21 in v2) with a serio adaptor
>    (patch 11/16 in this series). The adaptor allows us to take advantage of the
>    existing chardevs provided by serio.
> 
> [1] https://lore.kernel.org/linux-arm-kernel/37e75b07-a5c6-422f-84b3-54f2bea0b917@xxxxxxxxxxxxxxxx/
> 
> Finally, I've also addressed Zev Weiss' review comments where I thought it was
> required. These comments covered a lot of minor issues across (almost) all the
> patches, so it's best to review from a clean slate rather than attempt to review
> the differences between spins.
> 
> Previously:
> 
> Changes in v2 include:
> 
> * A rebase onto v5.12-rc2
> * Incorporation of off-list feedback on SerIRQ configuration from
>   Chiawei
> * Further validation on hardware for ASPEED KCS devices 2, 3 and 4
> * Lifting the existing single-open constraint of the IPMI chardev
> * Fixes addressing Rob's feedback on the conversion of the ASPEED KCS
>   binding to dt-schema
> * Fixes addressing Rob's feedback on the new aspeed,lpc-interrupts
>   property definition for the ASPEED KCS binding
> 
> Please test and review!
> 
> Andrew
> 
> Andrew Jeffery (16):
>   ipmi: kcs_bmc_aspeed: Use of match data to extract KCS properties
>   ipmi: kcs_bmc: Make status update atomic
>   ipmi: kcs_bmc: Rename {read,write}_{status,data}() functions
>   ipmi: kcs_bmc: Split out kcs_bmc_cdev_ipmi
>   ipmi: kcs_bmc: Turn the driver data-structures inside-out
>   ipmi: kcs_bmc: Split headers into device and client
>   ipmi: kcs_bmc: Strip private client data from struct kcs_bmc
>   ipmi: kcs_bmc: Decouple the IPMI chardev from the core
>   ipmi: kcs_bmc: Allow clients to control KCS IRQ state
>   ipmi: kcs_bmc: Don't enforce single-open policy in the kernel
>   ipmi: kcs_bmc: Add serio adaptor
>   dt-bindings: ipmi: Convert ASPEED KCS binding to schema
>   dt-bindings: ipmi: Add optional SerIRQ property to ASPEED KCS devices
>   ipmi: kcs_bmc_aspeed: Implement KCS SerIRQ configuration
>   ipmi: kcs_bmc_aspeed: Fix IBFIE typo from datasheet
>   ipmi: kcs_bmc_aspeed: Optionally apply status address
> 
>  .../bindings/ipmi/aspeed,ast2400-kcs-bmc.yaml | 106 +++
>  .../bindings/ipmi/aspeed-kcs-bmc.txt          |  33 -
>  drivers/char/ipmi/Kconfig                     |  27 +
>  drivers/char/ipmi/Makefile                    |   2 +
>  drivers/char/ipmi/kcs_bmc.c                   | 526 ++++-----------
>  drivers/char/ipmi/kcs_bmc.h                   |  92 +--
>  drivers/char/ipmi/kcs_bmc_aspeed.c            | 635 +++++++++++++-----
>  drivers/char/ipmi/kcs_bmc_cdev_ipmi.c         | 568 ++++++++++++++++
>  drivers/char/ipmi/kcs_bmc_client.h            |  48 ++
>  drivers/char/ipmi/kcs_bmc_device.h            |  22 +
>  drivers/char/ipmi/kcs_bmc_npcm7xx.c           |  94 ++-
>  drivers/char/ipmi/kcs_bmc_serio.c             | 151 +++++
>  12 files changed, 1582 insertions(+), 722 deletions(-)
>  create mode 100644 Documentation/devicetree/bindings/ipmi/aspeed,ast2400-kcs-bmc.yaml
>  delete mode 100644 Documentation/devicetree/bindings/ipmi/aspeed-kcs-bmc.txt
>  create mode 100644 drivers/char/ipmi/kcs_bmc_cdev_ipmi.c
>  create mode 100644 drivers/char/ipmi/kcs_bmc_client.h
>  create mode 100644 drivers/char/ipmi/kcs_bmc_device.h
>  create mode 100644 drivers/char/ipmi/kcs_bmc_serio.c
> 
> -- 
> 2.27.0
>