Getting Geoclue2 (and KDE/Gnome) to read data from GPSD.

[netsplit]

This is a script and config to create a NMEA feed for Geoclue from GPSD JSON. It works using socat and gpspipe from GPSD I'm posting it for some future person who has the same problem. So many times other people's answers have helped me here. If anyone has any suggestions to improve this please let me know. I'm at the skill level of a monkey poking a computer with a stick, so don't use this for anything important.


Scenario: Getting KDE Nightlight and other Geoclue dependent things working from GPS . It requires Geoclue which can read NMEA data. GPSD can output NMEA directly, but you have to turn off JSON data to do it. If you just want NMEA, this might something to look into. If you want both NMEA and JSON output, GPSD comes with a tool to create a NMEA feed from it's JSON so you can have both.

Method: use gpspipe which comes with GPSD to translate the JSON to NMEA, and socat to create a Unix socket to feed that data into Geoclue. Put it in a loop to hopefully make it so it recovers.

install (review GSPD use flags and configure uses if needed prior):

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emerge -av net-misc/socat sci-geosciences/gpsd app-misc/geoclue

Create a script to do this:
/usr/local/bin/nmeasource

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#!/bin/bash

while true; do
	logger -t geoclue-nmea "starting gpspipe socat listener"
	gpspipe -r | socat - UNIX-LISTEN:/run/gpsd-nmea.sock,fork,perm=666
	rm /run/gpsd-nmea.sock
	logger -t geoclue-nmea "error restarting gpspipe socat listener"
	sleep 5
done

Create an OpenRC init script to start it at boot:
/etc/init.d/nmeasource

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#!/sbin/openrc-run

name="$RC_SVCNAME"
description="Geoclue gpsd shim"
supervisor="supervise-daemon"
command="/usr/local/bin/nmeasource"


depend() {
    need gpsd
    after gpsd
    before geoclue
}

Set permissions and configure OpenRC to run scripts at boot:

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sudo chmod +x /etc/init.d/nmeasource
sudo chmod +x /usr/local/bin/nmeasource
sudo rc-update add gpsd default
sudo rc-update add nmeasource default
sudo rc-update add geoclue default

Configure Geoclue to read NMEA:
Make sure /etc/geoclue/geoclue.conf has this section:

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[network-nmea]
enable=true
nmea-socket=/run/gpsd-nmea.sock

Reboot! Hopefully it works now! Test it with (from a local user terminal, won't work over ssh or as root) /usr/libexec/geoclue-2.0/demos/where-am-i. If it works it'll give GPS data, If something is wrong it hang for a bit and close with no output. If this happens use this to find the problem:

From a root terminal run:

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killall geoclue && G_MESSAGES_DEBUG=all /usr/libexec/geoclue

Inspect for errors. If nothing obvious. Leave open the root terminal, and from a user terminal run /usr/libexec/geoclue-2.0/demos/where-am-i again. Then check the root terminal for errors.

Further semirelated. If your GPS doesn't work very well it might be in power saving mode. It goes into the reeds from that because how you fix that depends on the device. This works for my device, for example:

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//reset to default config
ubxtool --preset RESET
//set serial port speed
ubxtool --setspeed 9600 --file /dev/ttyAMA0
//turn of power management
ubxtool --preset CFG-PMS,0
//output twice a second 
ubxtool --preset CFG-RATE,500,1