LinPsk is a Psk31 and RTTY program for Linux using Qt.
It's roots are based on WinPsk 1.0.

LinPSK uses ALSA and can be configured to key your
radio using your serial port. Any number of homebrew
or commercially available serial port interfaces should
work for this purpose.

LinPSK can optionally be used with LinLogbook, which it
integrates with well (and is also available at Slackbuilds.org.)
