On Sun, 21 Nov 2010 david.schueler@xxxxxxxxxxxxxxxxxxx wrote: > -----Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> wrote: ----- > > >Sorry, I should have explained before -- I need the trace to start > >before the hang occurs. Ideally, start the trace before plugging in > >the FTDI device. Then for testing, just do an open followed by a > >close. > > Okay. Now i rebooted the system, started the logging of bus 3 to a file, > plugged the device out and in and started the reading of data with ws2500, > and the hang was caused. > Now i attach the log here. > Hopefully it will be needable. The problem does indeed show up right near the end of the log: > ffff88012bcca600 3109688350 S Bi:3:004:1 -115 512 < > ffff88012bcca600 3109689343 C Bi:3:004:1 0 2 = 0160 > ffff88012bcca600 3109689345 S Bi:3:004:1 -115 512 < > ffff88012bcca600 3109690343 C Bi:3:004:1 0 2 = 0160 > ffff88012bcca600 3109690349 S Bi:3:004:1 -115 512 < > ffff88012bcca600 3109691344 C Bi:3:004:1 0 3 = 016002 > ffff88012bcca600 3109691351 S Bi:3:004:1 -115 512 < > ffff88012bd9db40 3109817868 S Ci:3:004:0 s c0 05 0000 0000 0002 2 < > ffff88012bd9db40 3109819353 C Ci:3:004:0 0 2 = 0160 > ffff88012bd9db40 3109819383 S Co:3:004:0 s 40 01 0300 0000 0000 0 > ffff88012bd9db40 3109822349 C Co:3:004:0 0 0 > ffff88012bd9db40 3109822377 S Ci:3:004:0 s c0 05 0000 0000 0002 2 < > ffff88012bd9db40 3109825351 C Ci:3:004:0 0 2 = 0160 > ffff88012bd9db40 3109825390 S Co:3:004:0 s 40 01 0302 0000 0000 0 > ffff88012bd9db40 3109828350 C Co:3:004:0 0 0 > ffff88012bd9db40 3109828385 S Co:3:004:0 s 40 04 0008 0000 0000 0 > ffff88012bd9db40 3109831350 C Co:3:004:0 0 0 > ffff88012bd9db40 3109831367 S Co:3:004:0 s 40 03 4138 0000 0000 0 > ffff88012bd9db40 3109834356 C Co:3:004:0 0 0 > ffff88012bd9db40 3109834391 S Co:3:004:0 s 40 02 0000 0000 0000 0 > ffff88012bd9db40 3109837350 C Co:3:004:0 0 0 > ffff88012bd9db40 3109837379 S Co:3:004:0 s 40 01 0300 0000 0000 0 > ffff88012bd9db40 3109840350 C Co:3:004:0 0 0 > ffff88012bd9db40 3109840392 S Co:3:004:0 s 40 02 0000 0000 0000 0 > ffff88012bd9db40 3109843351 C Co:3:004:0 0 0 > ffff88012bd9db40 3109843375 S Co:3:004:0 s 40 01 0300 0000 0000 0 > ffff88012bd9db40 3109846349 C Co:3:004:0 0 0 There's a nice alteration of 'S' lines followed by 'C' lines except in one place: The final "S Bi:3:004:1" line has no corresponding 'C' line. That's the reason for the hang. Try one more test: While the ws2500 program is running, make a copy of both the "async" and "registers" files in /sys/kernel/debug/usb/ohci/0000:00:02.0/. Then try to make a second copy after shutting down the program and causing it to hang. Depending on how this works out, I'll have to send you some diagnostic patches to get more information from the ohci-hcd driver. Alan Stern -- 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
