Installation Notes#

libgpiod#

A pure Pi-local build is not easily possible: Pi autoconf is still at version 2.69, and libgpiod requires 2.70 (I guess). Don’t want to go through the process of autotooling on the Pi anyway, because the plan of autotools is to create a portable configure script, and a tarball containing all that’s necessary.

Fedora: Prepare Tarballs#

  • autoconf-archive is required because libgpiod uses M4 macros that are not present in stock autoconf.

    $ sudo dnf install autoconf-archive

  • Clone; I use master branch for no apparent reason (except that it works, maybe)

    $ pwd
/home/jfasch/work/blink

$ git clone https://git.kernel.org/pub/scm/libs/libgpiod/libgpiod.git
$ cd libgpiod
$ git branch -a
* master
  remotes/origin/HEAD -> origin/master
  remotes/origin/master
  remotes/origin/v0.1.x
  remotes/origin/v0.2.x
  remotes/origin/v0.3.x
  remotes/origin/v1.0.x
  remotes/origin/v1.1.x
  remotes/origin/v1.2.x
  remotes/origin/v1.3.x
  remotes/origin/v1.4.x
  remotes/origin/v1.5.x
  remotes/origin/v1.6.x
  remotes/origin/v2.0.x

  • Create autotoolery

    autogen.sh does a configure step (in the source directory!) by default; use NOCONFIGURE=yes to suppress that

    $ pwd
/home/jfasch/work/blink/libgpiod

$ NOCONFIGURE=yes ./autogen.sh
... better now ...

  • Create build directory, build locally

    To create tarballs for the final Pi build, we need to build locally first: manual pages are created by simply absorbing the tools output.

    Be aware that --enable-tools is necessary to create tarballs.

    $ pwd
/home/jfasch/work/blink/libgpiod

$ mkdir ../libgpiod-build
$ cd ../libgpiod-build

    $ pwd
/home/jfasch/work/blink/libgpiod-build

$ ../libgpiod/configure --enable-tools
$ make all dist-xz

    All we need from this step is libgpiod-2.1.tar.xz:

    $ ls -l libgpiod-2.1.tar.xz
-rw-r--r--. 1 jfasch jfasch 406332 Apr  5 15:42 libgpiod-2.1.tar.xz

    Transfer tarball over to Pi:

    $ scp /home/jfasch/work/blink/libgpiod-build/libgpiod-2.1.tar.xz 192.168.1.82:

On The Pi: Build And Install#

  • Prerequisites: setuptools

    $ sudo apt install python3-pip
$ python -m pip install setuptools

    (Actually, setuptools is installed along with pip)

  • Build and install libgpiod (might want to omit --enable-bindings-cxx)

    $ pwd
/home/jfasch/blink

$ tar xf ~/libgpiod-2.1.tar.xz
$ cd libgpiod-2.1/
$ ./configure --enable-bindings-cxx --enable-bindings-python  --enable-tools --prefix=/home/jfasch/blink/install
$ make
$ make install

  • Point PYTHONPATH and LD_LIBRARY_PATH

    $ export PYTHONPATH=/home/jfasch/blink/install/lib/python3.9/site-packages/gpiod-2.0.0-py3.9-linux-aarch64.egg/
$ export LD_LIBRARY_PATH=/home/jfasch/blink/install/lib