PCCARD - interruptible sleep

[Warner Losh]

From: "Attilio Rao" <attilio at freebsd.org>
Subject: Re: PCCARD - interruptible sleep
Date: Wed, 8 Nov 2006 14:43:59 +0100

> 2006/11/8, Jacqueline P <jackie7691 at yahoo.com.mx>:
> > Hi all
> >
> >  how can I implement an interruptible sleep within my pccard smart card reader driver like ?
> >  For Linux I do this the following way
> >
> >  // interruptible_pause()
> > static inline void ipause(unsigned long amount) {
> >  set_current_state(TASK_INTERRUPTIBLE);
> >  schedule_timeout(amount);
> > }
> >
> >  and within my driver I use the function DELAY which does a busy wait.
> >
> >  The problem is, that the driver does not recognize when the pccard is detached during a read / write operation.
> >
> >  Does the kernel update the struct device_t, so that the driver can use the function device_is_attached() to determine that the device is detached ?
> 
> You can implement a 'dying' flag in your softc structure (and
> subsequent macro in order to handle).

But that won't tell you if the hardware has disappeared.  Experience
has shown that dying isn't such a good idea in many cases and tends to
cause more races than it solves.

Warner