Re: [stable] [PATCH] i2c: fix bit algorithm timeout for low values.

[Greg KH <greg-U8xfFu+wG4EAvxtiuMwx3w@public.gmane.org>]

On Fri, Apr 24, 2009 at 11:42:59AM +0200, Jean Delvare wrote:
> Hi Dave,
> 
> On Fri, 24 Apr 2009 09:09:13 +1000, Dave Airlie wrote:
> > From: Dave Airlie <airlied-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
> > 
> > When fetching DDC using i2c algo bit, we were often seeing timeouts
> > before getting valid EDID on a retry. The VESA spec states 2ms is the
> > DDC timeout, so when this translates into 1 jiffie and we are close
> > to the end of the time period, it could return with a timeout less than
> > 2ms.
> > 
> > Change this code to use time_after instead of time_after_eq.
> > 
> > Signed-off-by: Dave Airlie <airlied-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
> > ---
> >  drivers/i2c/algos/i2c-algo-bit.c |    2 +-
> >  1 files changed, 1 insertions(+), 1 deletions(-)
> > 
> > diff --git a/drivers/i2c/algos/i2c-algo-bit.c b/drivers/i2c/algos/i2c-algo-bit.c
> > index d420cc5..e25e139 100644
> > --- a/drivers/i2c/algos/i2c-algo-bit.c
> > +++ b/drivers/i2c/algos/i2c-algo-bit.c
> > @@ -104,7 +104,7 @@ static int sclhi(struct i2c_algo_bit_data *adap)
> >  		 * chips may hold it low ("clock stretching") while they
> >  		 * are processing data internally.
> >  		 */
> > -		if (time_after_eq(jiffies, start + adap->timeout))
> > +		if (time_after(jiffies, start + adap->timeout))
> >  			return -ETIMEDOUT;
> >  		cond_resched();
> >  	}
> 
> Applied, thanks. I agree this should go in stable.

I don't see this in Linus's tree anywhere, am I just missing it?

thanks,

greg k-h