SP8 - cannot compile ipts

[aleksfadini]

I am running a surface-linux kernel on my SP8, see below.

$ uname -a
Linux AgileFenix 5.18.5-arch1-1-surface #1 SMP PREEMPT_DYNAMIC Mon, 20 Jun 2022 07:54:30 +0000 x86_64 GNU/Linux

yet I get this:

$ ls -l /dev/ipts/
ls: cannot access '/dev/ipts/': No such file or directory

and this:

$ ninja -C build

[ ... fails with ... ]

/usr/include/fmt/format.h:3064:21: note: declared here
 3064 | FMT_DEPRECATED auto format_to(basic_memory_buffer<char, SIZE, Allocator>& buf,
      |                     ^~~~~~~~~
cc1plus: all warnings being treated as errors
ninja: build stopped: subcommand failed.

I know other users have had better luck with ipts and SP8, what am I doing wrong?

[qzed]

You'll need the (work-in-progress) ithc driver from https://github.com/quo/ithc-linux and corresponding iptsd (https://github.com/quo/iptsd). See also linux-surface/intel-precise-touch#8 and linux-surface/intel-precise-touch#14.

As to the compiler error: You can work around that with meson configure -Dwerror=false, but we should fix that... cc @StollD.

[aleksfadini]

Thank you for the reply. I have the latest ithc from git (and it made single touch work!).

I did came here from the two threads you mentioned from the Linux-surface issues page.

I will try the workaround and report back.

[aleksfadini]

Thank you, I managed to compile iptsd using the workaround you suggested.
However I realized I do not have /dev/ipts, despite running surface-linux latest kernel.

sudo ./build/iptsd
ERROR: ../src/control.c:139: Failed to open /dev/ipts/0: No such file or directory
ERROR: ../src/main.c:106: Failed to start IPTS: No such file or directory
[aleks@AgileFenix iptsd]$ ls -l /dev/ipts/
ls: cannot access '/dev/ipts/': No such file or directory

This was a bit surprising given that the readme in this repo says:

You need to have the latest UAPI version of the IPTS kernel driver installed. All recent linux-surface kernels already include this.

However I do not have that driver I suppose? Am I doing something wrong? I wanted to enable multi touch on my SP8.

PS: I understand that this is highly experimental, and I might be too ignorant to handle it.

[qzed]

However I realized I do not have /dev/ipts, despite running surface-linux latest kernel.

AFAIK the ITHC driver doesn't provide /dev/ipts and works with hidraw. So things should work without it. ITHC is essentially a replacement for the IPTS kernel driver.

[StollD]

Are you building quos iptsd fork? https://github.com/quo/iptsd

Regarding the error from the first post, could you post the full output? I dont have any errors on Fedora 36 (neither with gcc nor with clang).

[aleksfadini]

Are you building quos iptsd fork? https://github.com/quo/iptsd

I am an idiot. I was building from https://github.com/linux-surface/iptsd instead of https://github.com/quo/iptsd !
Thank you for pointing this out.

Building from https://github.com/quo/iptsd , as you suggested, everything worked perfect. On my SP8 on Arch I now have multi touch and the pen works (eraser included!). 🎉

(closing this issue here, it's due to me not following directions)