Device has no u-blox chip (/dev/ttyHS0 missing). GPS is via the Quectel
EC25 LTE modem. Uncommented qcomgpsd in process_config.
GPS hardware confirmed working — modem returns fix via AT+QGPSLOC with
7 satellites, 1m accuracy. However qcomgpsd's diag interface reader
appears to stall after setup — the cereal gpsLocationExternal message
is not being populated. The diag subprocess exits as a zombie. Needs
further investigation into the ModemDiag interface.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>