Matching USB modems on serial.port
adrian at humboldt.co.uk
Thu Jan 29 02:32:38 PST 2009
I'm working on HAL support for an unreleased 3G modem. I've noticed that a lot of the USB modems in 10-modem.fdi match against the "serial.port" key, including ones recently added such as this patch:
Is this correct? My testing indicates that the "serial.port" key changes depending on the plugging order, and what other devices are attached. For example, my modem implements four serial ports. If I plug it in once, they are assigned serial.port values of 0,1,2,3. If I open /dev/ttyACM1 with a terminal program, unplug the modem (terminal still open), then replug the modem the serial.port values change to 0,2,3,4.
If I only match the modem on "@info.parent:usb.interface.number" the HAL behavior is correct in the unplug and replug scenario above.
Adrian Cox <adrian at humboldt.co.uk>
More information about the hal