Am Sonntag, 28. Juni 2009 20:29:26 schrieb Arseniy Lartsev: > I've got a piece of hardware (this one: > http://masterkit.ru/main/set.php?num=1153) which acts like an USB ACM > device and is handeled by the cdc_acm module. /dev/ttyACM0 does appear > but any attempt to write something to the device with a simple > "echo something >/dev/ttyACM0" fails with "Invalid argument" error. > > The reason is that the driver calls usb_submit_urb in acm_start_wb() > but doesn't set interval in the urb structure, so it remains zero and > causes usb_submit_urb to return -EINVAL. Reading from device also does > not work due to the same problem in acm_rx_tasklet(). This is supposed to write to bulk endpoints. There's no reason interval would need to be specified. Something is very odd. Please post "lsusb -v". 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
