Re: lpt stopped working

On Wednesday 11 February 2009, Alexey Shuvaev wrote:
> On Tue, Feb 10, 2009 at 05:34:10PM -0500, John Baldwin wrote:
> > On Tuesday 10 February 2009 4:57:20 pm Alexey Shuvaev wrote:
> > > On Tue, Feb 10, 2009 at 04:12:57PM -0500, John Baldwin wrote:
> > > > Ok, so the first cat works, the second one gets EBUSY?
> > >
> > > Mmm... I don't think the first cat really works.
> > > It hangs, I suppose nothing goes to the wire,
> > > and during this I got the above printigs from kgdb.
> > >
> > > > Hmm, I think I've found it.  Due to a bug, lptclose() wasn't
> > > > releasing the bus.
> >
> > Grr, lptopen() was also busted.  The old lpt driver didn't actually check
> > the HAVEBUS flag in lpt_release_ppbus() which masked the bugs in
> > lptopen().  Try this:
> >
> > --- //depot/vendor/freebsd/src/sys/dev/ppbus/lpt.c	2009/01/26 21:00:15
> > +++ //depot/user/jhb/acpipci/dev/ppbus/lpt.c	2009/02/10 22:32:11
> > _at__at_ -544,10 +544,10 _at__at_
> >  	do {
> >  		/* ran out of waiting for the printer */
> >  		if (trys++ >= LPINITRDY*4) {
> > -			sc->sc_state = 0;
> >  			lprintf(("status %x\n", ppb_rstr(ppbus)));
> >
> >  			lpt_release_ppbus(lptdev);
> > +			sc->sc_state = 0;
> >  			ppb_unlock(ppbus);
> >  			return (EBUSY);
> >  		}
> > _at__at_ -555,9 +555,8 _at__at_
> >  		/* wait 1/4 second, give up if we get a signal */
> >  		if (ppb_sleep(ppbus, lptdev, LPPRI | PCATCH, "lptinit",
> >  		    hz / 4) != EWOULDBLOCK) {
> > +			lpt_release_ppbus(lptdev);
> >  			sc->sc_state = 0;
> > -
> > -			lpt_release_ppbus(lptdev);
> >  			ppb_unlock(ppbus);
> >  			return (EBUSY);
> >  		}
> > _at__at_ -577,7 +576,8 _at__at_
> >
> >  	ppb_wctr(ppbus, sc->sc_control);
> >
> > -	sc->sc_state = OPEN;
> > +	sc->sc_state &= ~LPTINIT;
> > +	sc->sc_state |= OPEN;
> >  	sc->sc_xfercnt = 0;
> >
> >  	/* only use timeout if using interrupt */
> > _at__at_ -611,11 +611,8 _at__at_
> >  	int err;
> >
> >  	ppb_lock(ppbus);
> > -	if (sc->sc_flags & LP_BYPASS) {
> > -		sc->sc_state = 0;
> > -		ppb_unlock(ppbus);
> > +	if (sc->sc_flags & LP_BYPASS)
> >  		goto end_close;
> > -	}
> >
> >  	if ((err = lpt_request_ppbus(lptdev, PPB_WAIT|PPB_INTR)) != 0) {
> >  		ppb_unlock(ppbus);
> > _at__at_ -635,16 +632,16 _at__at_
> >  	sc->sc_state &= ~OPEN;
> >  	callout_stop(&sc->sc_timer);
> >  	ppb_wctr(ppbus, LPC_NINIT);
> > -	sc->sc_state = 0;
> > -	sc->sc_xfercnt = 0;
> >
> >  	/*
> >  	 * unregistration of interrupt forced by release
> >  	 */
> >  	lpt_release_ppbus(lptdev);
> > -	ppb_unlock(ppbus);
> >
> >  end_close:
> > +	sc->sc_state = 0;
> > +	sc->sc_xfercnt = 0;
> > +	ppb_unlock(ppbus);
> >  	lprintf(("closed.\n"));
> >  	return(0);
> >  }
>
> Seems to work!
> No messages in the console, like "interrupt storm", too.
> Thanks!
>
> Alexey.

That works for me, too. Thanks for fixing it!

Christian.