Lenovo T470s Questions

[Michael Gmelin]

On Fri, 2 Feb 2018 11:11:15 +0100
Jan Bramkamp <crest at rlwinm.de> wrote:

> On 02.02.18 03:13, Bridger Dyson-Smith wrote:
> > Hi list and Michael -
> > 
> > I received a T470s at work and decided to jump into the CURRENT end
> > of the FreeBSD pool. I have a weird acpi_ibm issue and I'm not sure
> > where to start trying to diagnose the issue.
> > 
> > # uname -a
> > FreeBSD spanner 12.0-CURRENT FreeBSD 12.0-CURRENT #0 r328126: Thu
> > Jan 18 15:25:44 UTC 2018     root at releng3.nyi.freebsd.org:/
> > usr/obj/usr/src/amd64.amd64/sys/GENERIC  amd64
> > 
> > I've loaded acpi_ibm via /boot/loader.conf:
> > acpi_ibm_load="YES"
> > 
> > and the module shows as being loaded:
> > # kldstat | grep acpi_ibm
> > 8    1 0xffffffff8278e000 7570     acpi_ibm.ko
> > 
> > However, I don't have any of the sysctl knobs available; e.g.
> > # sysctl -a | grep acpi_ibm
> > #
> > 
> > or
> >   # sysctl dev.acpi_ibm.0.fan_speed
> > sysctl: unknown oid 'dev.acpi_ibm.0.fan_speed'
> > 
> > I've (tried) to look through the commit messages on svn-src-head,
> > but I'm not seeing anything specifically related to acpi work, or I
> > just don't know what I'm looking at (a definite possibility).  
> 
> I made the same discovery on my T470s running FreeBSD 12-CURRENT. It
> has been a long time since Thinkpads were designed by IBM. The fan
> control works just fine without any special purpose module. The
> acpi_ibm module main usecase for me was always handling the special
> button events, but these days they are just secondary function on the
> regular function keys. Who needs an additional row of buttons on >2k€
> laptop when you can waste the space on a large useless trackpad.

I personally love having a large, well built trackpad *and* function
keys.

That aside, I've been working on a patch to acpi_ibm to support special
button events, bluetooth on/off and controlling the keyboard
backlight (not just for the T470s, but also for other recent Lenovo
models). I still need to update the man page and polish it, but it's
already available in a code review and I use it myself successfully (I
didn't look into things like fan control though, as those really
shouldn't be touched these days):

https://reviews.freebsd.org/D14103

Direct link to the patch:

https://reviews.freebsd.org/D14103?download=true

Testers and code reviews are welcome.

Best,
Michael

p.s. Make sure to load the correct kernel module in case you rebuilt
it individually.

-- 
Michael Gmelin