Hello,

I'm operating an EVB (evaluation board) through a
USB<=>SERIAL bridge (TUSB3410) and PerlTk script
which sends/receives message strings to/from the EVB.
The USB bridge is detected as /dev/ttyUSB*. Once in a while
the EVB (or the firmware on it responsible for the
communication) got "stuck" and on the LINUX side I'm getting
the "broken pipe" messages when attempting "sysread/syswrite".
If I go to the EVB, disconnect the USB connector and re-connect it
I cause the device first to disappear then to be re-discovered
and communication resuls. But I'm looking for some solution that
can be done programmatically, without me physically going to the
EVB and disconnecting and reconnecting the USB.

Can I somehow "force" linux to disconnect a stuck USB device and
to re-discover it again, as if the USB connector had been
disconnected and reconnected again?

TIA for any help,

Greetingz!

I've come across a similar problem; I run a "console server" (a 16-port USB hub with lots of USB-to-serial adapters).
You could try to unload the usbserial module; (if it's an actual module, and not compiled-in to the kernel)

1) Do a 'lsmod|grep usbserial' to see if the module's loaded.
2) A 'rmmod usbserial' to pop-out the driver support (note: *all* USB Serial connectors will offline when you do this)
3) Wait a second or two, then do a 'modprobe usbserial'

1 members found this post helpful.

Thanks, xeleema!

Your reply pointed me into the right direction.
Doing "lsmod" I saw that the "usbserial" module is in use
by the driver of that particular bridge (from memory: ti_usb_3410_5052),
so removing it and then re-adding does what I need.

Regards,