Re:Re:Re: [RFC PATCH 4/6] net: wwan: add NMEA port support

["Slark Xiao" <slark_xiao@163.com>]

Hi Sergey,
Do we have any updates about this feature? I didn't see any new patch or review suggestion.
Seems this task is pending without any push.

Thanks
Slark
At 2025-04-29 14:34:04, "Slark Xiao" <slark_xiao@163.com> wrote:
>
>
>At 2025-04-28 21:23:53, "Muhammad Nuzaihan Kamal Luddin" <zaihan@unrealasia.net> wrote:
>>Hi Slark,
>>
>>you cab add udev rules to set the permissions.
>>
>>Regards,
>>Zaihan
>>Sent from my iPhone
>>
>Hi Zaihan,
>Thanks for your advice.
>But I tried in my local, no matter the mode is 644 or 755, similar issue still exist.
>BTW, this error only was reported when I call "gpsmon" or "cgps" command.
>
>test reference as below:
>jbd@jbd:~$ cat /etc/udev/rules.d/99-gps.rules 
>KERNEL=="gnss0", MODE="0755", GROUP="dialout"
>
>4月 29 14:08:17 jbd gpsd[3544]: gpsd:ERROR: SER: device open of /dev/gnss0 failed: Permission denied - retrying read-only
>4月 29 14:08:17 jbd gpsd[3544]: gpsd:ERROR: SER: read-only device open of /dev/gnss0 failed: Permission denied
>4月 29 14:08:17 jbd gpsd[3544]: gpsd:ERROR: /dev/gnss0: device activation failed, freeing device.
>jbd@jbd:~$ 
>jbd@jbd:~$ ls -l /dev/gnss0 
>crwxr-xr-x 1 root dialout 237, 0  4月 29 14:05 /dev/gnss0
>
>Thanks
>>> On 28 Apr 2025, at 4:28 PM, Slark Xiao <slark_xiao@163.com> wrote:
>>> 
>>> 
>>> At 2025-04-09 18:42:59, "Sergey Ryazanov" <ryazanov.s.a@gmail.com> wrote:
>>>>> On April 9, 2025 11:30:58 AM GMT+03:00, Slark Xiao <slark_xiao@163.com> wrote:
>>>>> 
>>>>> Hi Sergey,
>>>>> Device port /dev/gnss0 is enumerated . Does it be expected?
>>>>> I can get the NMEA data from this port by cat or minicom command.
>>>>> But the gpsd.service also can not be initialized normally. It reports:
>>>>> 
>>>>> TriggeredBy: ● gpsd.socket
>>>>>   Process: 3824 ExecStartPre=/bin/stty speed 115200 -F $DEVICES (code=exited, status=1/FAILURE)
>>>>>       CPU: 7ms
>>>>> 
>>>>> 4月 09 16:04:16 jbd systemd[1]: Starting GPS (Global Positioning System) Daemon...
>>>>> 4月 09 16:04:17 jbd stty[3824]: /bin/stty: /dev/gnss0: Inappropriate ioctl for device
>>>>> 4月 09 16:04:17 jbd systemd[1]: gpsd.service: Control process exited, code=exited, status=1/FAILURE
>>>>> 4月 09 16:04:17 jbd systemd[1]: gpsd.service: Failed with result 'exit-code'.
>>>>> 4月 09 16:04:17 jbd systemd[1]: Failed to start GPS (Global Positioning System) Daemon.
>>>>> 
>>>>> Seems it's not a serial port.
>>>> 
>>>> It is a char dev lacking some IOCTLs support. Yeah.
>>>> 
>>>>> Any advice?
>>>> 
>>>> Yep. Remove that stty invocation from the service definition. For me, gpsd works flawlessly. You can try to start it manually from a terminal.
>>>> 
>>>> --
>>>> Sergey
>>> Hi Sergey,
>>> My device could output the NMEA data by port /dev/gnss0. Something like below:
>>> 
>>> $GPRMC,071634.00,A,2239.372067,N,11402.653048,E,,,280425,,,A,V*2D
>>> $GARMC,071634.00,A,2239.372067,N,11402.653048,E,,,280425,,,A,V*3C
>>> $GBRMC,071634.00,A,2239.372067,N,11402.653048,E,,,280425,,,A,V*3F
>>> $GNRMC,071634.00,A,2239.372067,N,11402.653048,E,,,280425,,,A,V*33
>>> $GNGNS,071634.00,2239.372067,N,11402.653048,E,NAANNN,02,500.0,,,,,V*15
>>> $GPGGA,071634.00,2239.372067,N,11402.653048,E,1,00,500.0,,,,,,*59
>>> $GAGGA,071634.00,2239.372067,N,11402.653048,E,1,01,500.0,,,,,,*49
>>> $GBGGA,071634.00,2239.372067,N,11402.653048,E,1,00,500.0,,,,,,*4B
>>> $GNGGA,071634.00,2239.372067,N,11402.653048,E,1,02,500.0,,,,,,*45
>>> $GPGSV,4,1,13,04,00,038,,05,33,240,,06,41,033,,09,25,058,,1*6F
>>> $GPGSV,4,2,13,11,47,344,,12,33,286,,13,09,185,,17,29,128,,1*6E
>>> $GPGSV,4,3,13,19,54,113,,20,62,284,,22,15,174,,25,09,311,,1*68
>>> $GPGSV,4,4,13,40,00,000,28,1*58
>>> $GLGSV,3,1,09,10,19,245,,06,38,185,,09,06,203,,11,13,296,,1*79
>>> $GLGSV,3,2,09,05,60,064,,20,39,013,,19,17,084,,21,15,321,,1*7E
>>> $GLGSV,3,3,09,04,16,030,,1*41
>>> $GAGSV,3,1,11,02,30,297,,04,32,076,,05,10,188,,06,41,107,,7*78
>>> $GAGSV,3,2,11,09,39,140,,10,26,055,,11,42,027,,12,09,071,,7*7E
>>> $GAGSV,3,3,11,16,36,198,,24,19,176,,36,39,317,,7*45
>>> $GBGSV,4,1,15,01,47,122,,02,46,234,,03,63,189,,04,34,108,,1*7D
>>> $GBGSV,4,2,15,05,23,253,,06,04,187,,07,86,194,,08,68,284,,1*75
>>> $GBGSV,4,3,15,09,03,201,,10,78,299,,11,56,025,,12,29,094,,1*71
>>> 
>>> But the gpsd progress were stuck with below errors:
>>> ● gpsd.service - GPS (Global Positioning System) Daemon
>>>     Loaded: loaded (/lib/systemd/system/gpsd.service; enabled; vendor preset: enabled)
>>>     Active: active (running) since Mon 2025-04-28 23:16:47 CST; 20s ago
>>> TriggeredBy: ● gpsd.socket
>>>    Process: 5281 ExecStart=/usr/sbin/gpsd $GPSD_OPTIONS $OPTIONS $DEVICES (code=exited, status=0/SUCCESS)
>>>   Main PID: 5283 (gpsd)
>>>      Tasks: 1 (limit: 37272)
>>>     Memory: 652.0K
>>>        CPU: 10ms
>>>     CGroup: /system.slice/gpsd.service
>>>             └─5283 /usr/sbin/gpsd -F /var/run/gpsd.sock /dev/gnss0
>>> 
>>> 4月 28 23:16:47 jbd systemd[1]: Starting GPS (Global Positioning System) Daemon...
>>> 4月 28 23:16:47 jbd systemd[1]: Started GPS (Global Positioning System) Daemon.
>>> 4月 28 23:17:02 jbd gpsd[5283]: gpsd:ERROR: SER: device open of /dev/gnss0 failed: Permission denied - retrying read-only
>>> 4月 28 23:17:02 jbd gpsd[5283]: gpsd:ERROR: SER: read-only device open of /dev/gnss0 failed: Permission denied
>>> 4月 28 23:17:02 jbd gpsd[5283]: gpsd:ERROR: /dev/gnss0: device activation failed, freeing device.
>>> 
>>> And I checked the gnss device attribute, it reports:
>>> crw------- 1 root root 237, 0  4月 28  2025 /dev/gnss0
>>> 
>>> May I know how do you fix this?
>>> 
>>> Thanks
>>> 
>>>