Hi list participants,
I am using cellphones connected to soundcards as cheap gsm gateways (more complex than that, actually. You can see the whole GPL project at www.celliax.org).
Maybe there is a way to not using soundcards, that would be *so* much better: I found that Motorola c350 phones after receiving an AT+MODE=8 command via USB, make available an usb sound device.
That would be wonderful (less cables, more robustness, etc). Problem is: the usb sound device do not plays or captures samples.
I suspect that the usb audio has to be activated, maybe by an AT or a P2K command.
Or that a quirk has to be added to the alsa driver (snd_usb_audio).
Do you know anything about (maybe the quirk to be added to ALSA driver...)?
Do you have any hint?
I'm available to do all the research-testing-debugging that may be useful.
What happens is as follow: 1) attach the c350 to usb 2) is recognized as acm0 3) send at+mode=8 to c350 (via minicom, for eg) 4) it changes its usbid, disconnect from usb, reconnect, is recognized as acm1, makes available a sound device 5) at commands work on the new acm1 6) trying to use the audio device directly (eg aplay -Dhw:1) do not give errors on play (but no sound is head on the phone), gives error pcm_read 1349 on record (eg arecord -Dhw:1) 7) trying to use the audiodevice through alsalib does not gives errors at all (eg -Dplughw:1) but does not caputeres samples, and no sound is heard on the phone
In the tgz archive attached you can find the following files:
lusb_without -> result of lusb -vv with no device attached
lsusb_with_ACM0 -> result of lusb -vv with c350 just attached, recognized as acm modem
lsusb_with_ACM1 -> result of lusb -vv with c350 after sending at+mode=8 to him, he has disconnected and was recognized again, this time as ACM1, with a lot of additional usb interfaces
dmesg-acm0 -> result of dmesg after first c350 attachment
dmesg-acm1 -> result of dmesg after at+mode=8 was sent to the c350
aplay-l -> result of aplay -l showing the c350 as an alsa device
stream0_pstop_cstop -> result of cat /proc/asound/C350/stream0 while not active
stream0_pstop_crun -> result of cat /proc/asound/C350/stream0 while arecord -vv -Dplughw:1 -fS16_LE ciapa.raw (if using -Dhw:1 it fails with error: "pcm_read:1349: read error: Input/output error"). arecord does not gives errors, but do not write samples
stream0_prun_crun -> result of cat /proc/asound/C350/stream0 while aplay and arecord -vv -Dplughw:1 -fS16_LE ciapa.raw (if using -Dhw:1 arecord fails with error: "pcm_read:1349: read error: Input/output error", aplay works but no audio) arecord does not gives errors, but do not write samples
aplay_play -> results of aplay
arecord_rec -> results of arecord
Thank you all in advance,
Giovanni Maruzzelli