Greg KH <gre...@linuxfoundation.org> writes: > On Mon, Jun 10, 2013 at 06:56:30PM +0200, Ben Adler wrote: >> Hello Greg, >> >> thanks for getting back to me! >> >> >>I'm using a >> >>http://www.septentrio.com/products/receivers/asterx2i-oem INS/GNSS >> >>receiver. When connected via USB to a windows-host, there's two (or >> >>even three, don't remember exactly) virtual serial ports to talk to >> >>it. >> > >> >Why do you want to talk to the other ports? What is on those >> >connections? >> >> They're all serial ports, used to issue commands to the receiver (in >> binary or ascii form) and receive data at different intervals >> (again, binary or ascii). Which messages exactly are accepted or >> sent on which (virtual) port at which interval can be configured. > > That's not what the USB device descriptors you provided below show. > They look like a "normal" cdc-acm device, so we are (according to the > USB-IF specification), supposed to export to userspace a single device > that can be used to communicate with it.
Note that the lsusb output showed a second configuration with 2 vendor specific ACM functions (only 2 bulk endpoints and protocol = 0xff) instead of the single standard CDC ACM function. This is probably the configuration used by the Windows host. The cdc-acm driver cannot handle those ports, but a more forgiving generic driver can. I don't recommend it for normal use because it abuses the option driver, but Ben could do a simple test like this: echo 2 >/sys/bus/usb/devices/<usbportname>/bConfigurationValue modprobe option echo 152a 8230 > /sys/bus/usb-serial/drivers/option1/new_id Unless I missed something, this should result in two /dev/ttyUSBx serial devices. I guess this device is worth a new serial driver of its own in case that works? Or should we create a generic driver for 02/02/ff serial devices (using the inverse of the logic in drivers/net/usb/cdc_ether.c: usbnet_generic_cdc_bind to avoid RNDIS devices)? A few modems with such ports have been added to option, but a generic solution might be better. Bjørn -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
