Hi Hans,
On Fri, Feb 08, 2019 at 10:08:22AM +0100, Hans Verkuil wrote:
> On 2/8/19 10:06 AM, Sakari Ailus wrote:
> > On Fri, Feb 08, 2019 at 09:49:23AM +0100, Hans Verkuil wrote:
> >> The sd argument of this macro can be a more complex expression. Since it
> >> is used 5 times in the macro it can be evaluated that many times as well.
> >>
> >> So assign it to a temp variable in the beginning and use that instead.
> >>
> >> This also avoids any potential side-effects of evaluating sd.
> >>
> >> Signed-off-by: Hans Verkuil <hverkuil-cisco@xxxxxxxxx>
> >
> > Nice one!
> >
> > Acked-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
> >
> > I wonder if this addresses some of the sparse issues related to using a
> > macro to come up with sd?
>
> It does solve those as well, in fact :-)
>
> I rejected the omap3/4 patches in favor of this one, which is a much, much
> cleaner solution.
Thank you for looking into this. Great work :-)
Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
> >> ---
> >> diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h
> >> index 47af609dc8f1..34da094a3f40 100644
> >> --- a/include/media/v4l2-subdev.h
> >> +++ b/include/media/v4l2-subdev.h
> >> @@ -1093,13 +1093,14 @@ void v4l2_subdev_init(struct v4l2_subdev *sd,
> >> */
> >> #define v4l2_subdev_call(sd, o, f, args...) \
> >> ({ \
> >> + struct v4l2_subdev *__sd = (sd); \
> >> int __result; \
> >> - if (!(sd)) \
> >> + if (!__sd) \
> >> __result = -ENODEV; \
> >> - else if (!((sd)->ops->o && (sd)->ops->o->f)) \
> >> + else if (!(__sd->ops->o && __sd->ops->o->f)) \
> >> __result = -ENOIOCTLCMD; \
> >> else \
> >> - __result = (sd)->ops->o->f((sd), ##args); \
> >> + __result = __sd->ops->o->f(__sd, ##args); \
> >> __result; \
> >> })
> >>
--
Regards,
Laurent Pinchart
