Arch Linux

Vixus

Member

Registered: 2012-11-02

Posts: 60

X60 Serial Wacom Tablet undetected

As of late, the serial wacom tablet in my Thinkpad X60's screen is no longer detected automatically. The output of xsetwacom --list dev is empty and xinput no longer lists STYLUS or ERASER as devices.

The change seems to be that detection of serial wacom devices is now carried out by systemd in the following service file (since Apr 21 2014):

/usr/lib/systemd/system/wacom-inputattach@.service

The relevant log entries are here: http://ix.io/dJ2

The error reported by the service is:

● wacom-inputattach@ttyS0.service - inputattach for Wacom ISDv4-compatible serial devices
   Loaded: loaded (/usr/lib/systemd/system/wacom-inputattach@.service; static)
   Active: failed (Result: exit-code) since Sat 2014-08-02 20:03:33 BST; 22min ago
  Process: 288 ExecStart=/usr/bin/isdv4-serial-inputattach /dev/%I (code=exited, status=1/FAILURE)
 Main PID: 288 (code=exited, status=1/FAILURE)

Aug 02 20:03:33 vix60 isdv4-serial-inputattach[288]: timeout.
Aug 02 20:03:33 vix60 isdv4-serial-inputattach[288]: error during query.
Aug 02 20:03:33 vix60 isdv4-serial-inputattach[288]: Tablet query failed, cannot initialize.
Aug 02 20:03:33 vix60 systemd[1]: wacom-inputattach@ttyS0.service: main process exited, code=exited, status=1/FAILURE
Aug 02 20:03:33 vix60 systemd[1]: Unit wacom-inputattach@ttyS0.service entered failed state.
Aug 02 20:03:33 vix60 isdv4-serial-inputattach[288]: TABLET: version: 192
Aug 02 20:03:33 vix60 isdv4-serial-inputattach[288]: TABLET: x max: 24576 y max 18432
Aug 02 20:03:33 vix60 isdv4-serial-inputattach[288]: TABLET: tilt_x max: 0 tilt_y max 0
Aug 02 20:03:33 vix60 isdv4-serial-inputattach[288]: TABLET: pressure max: 255
Aug 02 20:03:33 vix60 isdv4-serial-inputattach[288]: Initial tablet query failed. Trying with baud rate 38400.

Here is a more verbose output:

# sudo isdv4-serial-inputattach --verbose /dev/input/wacom 
... Opening device '/dev/input/wacom'.
... Baud rate is 19200
... Querying tablet.
... Writing STOP command.
... Written '0'.
... Written '*'.
... Waiting for tablet...... data available.
... Reading 11 bytes from device.
... read 8 bytes in one chunk.
... read 3 bytes in one chunk.
... Read 11 bytes.
... Parsing query reply.
TABLET: version: 192
TABLET: x max: 24576 y max 18432
TABLET: tilt_x max: 0 tilt_y max 0
TABLET: pressure max: 255
... Trying touch query
... Writing STOP command.
... Written '0'.
... Written '%'.
timeout.
error during query.
... Waiting for tablet...Initial tablet query failed. Trying with baud rate 38400.
... Baud rate is 38400
... Querying tablet.
... Writing STOP command.
... Written '0'.
... Written '*'.
timeout.
error during query.
Tablet query failed, cannot initialize.
... Waiting for tablet...

so apparently the tablet does exist since it correctly reports its dimensions and pressure sensitivity. This just looks like a badly written detection code.

I have the following packages installed that, up til April 21, have been working perfectly for autodetecting the wacom input:

• xf86-input-evdev

• xf86-input-wacom

• wacom-udev installed today after following wiki pages

I have followed the instructions on the following pages:
https://wiki.archlinux.org/index.php/Wa … _with_udev
https://wiki.archlinux.org/index.php/Le … let#Stylus

The same issue (no solution) has been reported in Fedora Core 20 here:
http://forums.fedoraforum.org/showthrea … ost1696110

Last edited by Vixus (2014-08-02 19:27:27)

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github

Vixus

Member

Registered: 2012-11-02

Posts: 60

Re: X60 Serial Wacom Tablet undetected

Just some updates and proof that this isn't an issue with the physical hardware.

• wacom-udev's rules correctly symlink /dev/ttyS0 to /dev/input/wacom.

• Running the following produces output when the stylus interacts with the screen:

  sudo xxd /dev/input/wacom

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github

NoOneKnows

Member

Registered: 2014-08-12

Posts: 1

Re: X60 Serial Wacom Tablet undetected

Hi!
How are you logging into your system? I had the same problem while logging in via startx. Since I'm using lightdm my X61t is fully functional again.

Bye

Last edited by NoOneKnows (2014-08-12 08:00:14)

sqweek

Member

Registered: 2012-03-28

Posts: 2

Re: X60 Serial Wacom Tablet undetected

Heya, I had the same issue & symptoms on my X61 -- it's an upstream bug in xf86-input-wacom. It's not working with xf86-input-wacom 0.25.0-3, but I rebuilt from the git repo and my pen works again.

Unfortunately I think it was fixed in this commit, which has not yet made its way into an official release.

The problem appears to be that isdv4-serial-inputattach queries the tablet's pen AND touch capabilities at startup. Some pen-only tablets will respond with "Yep I have pen support" and then "Nope no touch support." However, tablets like ours respond with "Yep I have pen support" and then "..." -- silence.

isdv4-serial-inputattach was treating the tablet's failure to respond to the touch query as a fatal error, instead of proceeding with pen-only support.