On Fri, 18 Nov 2005, Paulo Marques wrote:
> After applying a slab-owner patch to find out who was > requesting > all that data, I found out that it was actually ftdi_write that > was > being called thousands of times. > > I inserted a dump_stack every 1024 calls to see the call chain > leading > to that, and this is a typical path: > > > dumping ftdi_write (count 1 data[0] == 0x41) [<c02c6403>] > > ftdi_write+0x93/0x2fb > > [<c02bc7cb>] serial_write+0x75/0x80 > > [<c01e8a32>] tty_default_put_char+0x1e/0x22 > > [<c01e94aa>] echo_char+0x48/0x68 > > [<c01e9f6b>] n_tty_receive_buf+0x652/0x9dc > > ... > > So it is actually echoing back the chars that it is receiving > :( > > The sequence I use is something like: > > # stty -F /dev/tts/0 3000000 raw > # cat /dev/tts/0 | xxd -g 1 -c 16 > > then, on another console: > > # printf "command to request a frame" > /dev/tts/0 > > The "raw" in the stty should disable echoing, no? No, it shouldn't. You have to disable echoing explicitly. Olav ------------------------------------------------------- This SF.Net email is sponsored by the JBoss Inc. Get Certified Today Register for a JBoss Training Course. Free Certification Exam for All Training Attendees Through End of 2005. For more info visit: http://ads.osdn.com/?ad_id=7628&alloc_id=16845&op=click _______________________________________________ linux-usb-devel@lists.sourceforge.net To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
