Reported by Radek Polak, Aug 28, 2013
Modem sometimes disconnect and reconnects back on USB. This makes the modem handling code unreliable and results e.g. in missed calls. How to reproduce: install QtMoko v55 from here: http://sourceforge.net/projects/qtmoko/files/GTA04/ From second phone start a call, let GTA04 ring a few times, then hangup. Repeat a few times until it happens (QtMoko restarts to recover, creates files /modem_reenumerate.txt). Btw QtMoko kernel sources are here: https://github.com/radekp/linux-2.6/tree/v3.7-gta04-qtmoko-v55 but i guess every kernel will do it.
Comment 1 by Radek Polak, Aug 28, 2013
For more details it was described e.g. here: http://lists.goldelico.com/pipermail/gta04-owner/2012-February/001563 .html If you want to easily reproduce you can e.g. use N900 as your second phone and write shell script for the dialing.
Comment 3 by Radek Polak, Aug 28, 2013
Small workaround is to put modem in 2G only, then the reenumeration should not occur that much. The AT command is: AT_OPSYS=0,2
Comment 4 by Nikolaus Schaller, Aug 28, 2013
There are several hypotheses what the reasons are: 1. modem firmware bug 2. linux kernel (general USB) / driver (HSO) 3. hardware 4. user space triggered (which I think is the least probable) We finally have to find out what the real reason is - and/or develop better work-arounds.
Comment 5 by Radek Polak, Aug 30, 2013
Attached is log from my phone. You can seach for string "Globetrotter" for reenumerates. The line "Hiding non-modal dialog: PhoneMessageBox" is for each call. At the end of log modem disconnects from USB and never connects back. Even after reboot there are no /dev/ttyHS ports and lsusb does not show the modem. After removing battery and booting again the modem is working again
- messages - 333.97 kB
Comment 6 by Radek Polak, Aug 30, 2013
Btw the log is taken with these modem settings: AT_OPSYS? _OPSYS: 3,2
Comment 7 by Radek Polak, Sep 4, 2013
Just for the record here are some interesting mails about the problem: http://lists.goldelico.com/pipermail/gta04-owner/2013-September/00493 3.html http://lists.goldelico.com/pipermail/gta04-owner/2013-September/00493 9.html
Comment 8 by Nikolaus Schaller, Sep 7, 2013
And another trick for testing the test code (which is important to know): ./femtocom /dev/ttyHS_Control AT_ORESET This will reset the modem and it will loose the USB connection and re-enumerate like this dmesg shows: [ 6940.011840] usb 1-2: USB disconnect, device number 5 [ 6945.105041] usb 1-2: new high-speed USB device number 6 using ehci-omap [ 6945.286895] usb 1-2: New USB device found, idVendor=0af0, idProduct=8800 [ 6945.300415] usb 1-2: New USB device strings: Mfr=3, Product=2, SerialNumber=0 [ 6945.323791] usb 1-2: Product: Globetrotter HSUPA Modem [ 6945.329132] usb 1-2: Manufacturer: Option N.V. As a side note: the modem accepts more at commands after AT_ORESET for ca. 1-2 seconds like this sequence shows: root@gta04:~# ./femtocom /dev/ttyHS_Control at_oreset OK ati Manufacturer: Option N.V. Model: GTM601 Revision: 184.108.40.206 (Date: Jan 5 2011, Time: 11:14:34) OK ati Manufacturer: Option N.V. Model: GTM601 Revision: 220.127.116.11 (Date: Jan 5 2011, Time: 11:14:34) OK ati ati <--- tty port hangs (w/o error message!) ati ati ati ati ^C root@gta04:~# So in general the re-enumeration shares the symptoms of an AT_ORESET.
Comment 9 by Nikolaus Schaller, Oct 1, 2013