On Sun, 6 Dec 2009 00:22:57 +0100 Oliver Neukum <oliver@xxxxxxxxxx> wrote: > Am Sonntag, 6. Dezember 2009 00:08:46 schrieb Alan Cox: > > Simply set port->port.drain_delay = 256; /* good first guess */ > > > > and the rest should happen automatically and correctly sequenced with the > > carrier and flow control signals. A lot of hardware just delays so it's > > entirely possible that there isn't a magic transmit drain in any given > > device. > > I suppose cdc-acm should do likewise, shouldn't it? Why would it? In case of MCT it's just the hardware ack-ing the transfer of data as soon as it reachets the dongle but before the stop bit left the serial pins. Do we know of a CDC-ACM device that suffers from it? This is actually easy to reproduce, just do while true; do echo -n "123" > /dev/ttyUSB0; done You'll see 121212 if device is broken and 123123123 if it's ok. -- Pete -- 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
