Re: [PATCH -mm] Blackfin: blackfin i2c driver

[Sonic Zhang]

On 3/6/07, Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> wrote:
> On Tue, 06 Mar 2007 14:54:18 +0800 "Wu, Bryan" <bryan.wu@xxxxxxxxxx> wrote:
>
> > Hi folks,
> >
> > [PATCH] Blackfin: blackfin i2c driver
> >

> > +     struct i2c_msg *pmsg;
> > +     int i, ret;
> > +     int rc = 0;
> > +
> > +     if (!(bfin_read_TWI_CONTROL() & TWI_ENA))
> > +             return -ENXIO;
> > +
> > +     down(&iface->twi_lock);
> > +
> > +     while (bfin_read_TWI_MASTER_STAT() & BUSBUSY) {
> > +             up(&iface->twi_lock);
> > +             schedule();
> > +             down(&iface->twi_lock);
> > +     }
>
> That's a busy loop until this task's timeslice has expired.  It'll work,
> but it'll suck a bit.  (Repeated in several places)

OK, I change it into yield(). So, current process will be move to the
tail of the run queue. Is that OK with you?
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