Add pp_serial driver for Pinephone without a SIM card
Add pp_serial
driver which runs the GNSS unit in the EG25 modem in the Pinephone with the AT-command interface and thus does not need ModemManager, or a SIM card installed in the phone.
ModemManager must be disabled / masked for this to work, but eg25-manager needs to be running for modem initialization.
The code is in a sort of 'works for me' state at the moment:
- It hardcodes the control port to
/dev/ttyUSB2
and the almanac data (XTRA) file for theload
command to/tmp/xtra.bin
. Configuration file variables would be needed for these. - XTRA loading code does not check all the responses from the hardware.
- The eg25-manager uses the same control port as this driver, which could cause problems at some point.
- I really don't know go, the code is mostly copied from the
stm_serial
driver and could have all kinds of stylistic and functional problems.
This said, it seems to work fine, Geoclue and other clients work OK.