Am Donnerstag, 26. August 2010, 10:26:54 schrieb Artem Makhutov: > Hello List, > > I am the author of chan_datacard, a module for Asterisk to used Huawei > UMTS modems to do voice calls. > > Me, and also a lot of users have troubles with using the Modems under Linux. > > This modems are using the option kernel module and the communication is > done using the /dev/ttyUSBX interface. > > When connecting multiple modems to a pc and start communicatin with them > the connection gets broken and the log file gets full of the following > messages: > > uname -a: > Linux box1 2.6.35-ARCH #2 SMP PREEMPT Sat Aug 14 21:58:00 CEST 2010 > x86_64 Intel(R) Atom(TM) CPU 330 @ 1.60GHz GenuineIntel GNU/Linux > > [...] > option: option_instat_callback: error -71 > option: option_instat_callback: error -71 > option: option_instat_callback: error -71 > [...] > > What does this error message mean? -EPROTO (*, **) a) bitstuff error b) no response packet received within the prescribed bus turn-around time c) unknown USB error > I can image that the modems are generating RF-interferences that may > interference on the usb-cables and cause transfer problems. Plausible. > Unfortunatly it looks like FreeBSD users do not have this problem. > > (So eigter FreeBSD has better capabilities to recover usb transfer > problems, or there is something wrong with the linux kernel. - I will > verify this by installing FreeBSD on the same box...) Please do so. > What logs do you need in order to trace this problem? Start by compiling your kernel with CONFIG_USB_DEBUG. We may then see which additional debug is required. Which HCD are you using? Regards Oliver -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
