[Linux-parport] ASYNC I/O Reason: Reverse transfers are _slow_
klammerr at aon.at
Tue Feb 2 10:04:53 EST 2010
Johann Klammer wrote:
> With the chipset I'm using(vt1211 superio) it seems necessary to
> initiate the first handshake manually by lowering PeriphClk. (the line
> with parport_frob_control (port, PARPORT_CONTROL_AUTOFD, 0);) Else it
Oops wrong. It should be: It seems necessary to
initiate the first handshake manually by raising HostAck==nAUTOFD. The code is fine though.
> I'll also try it on a more ancient intel mainboard later to see whether
> it is hardware specific.
Done. It works exactly the same on old Intel 440BX. DMA also hangs without frob_control...
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