From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from smtp-vbr10.xs4all.nl ([194.109.24.30]:3197 "EHLO smtp-vbr10.xs4all.nl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932514AbaCQLpg (ORCPT ); Mon, 17 Mar 2014 07:45:36 -0400 Message-ID: <5326E04C.5050808@xs4all.nl> Date: Mon, 17 Mar 2014 12:45:16 +0100 From: Hans Verkuil MIME-Version: 1.0 To: Laurent Pinchart CC: linux-media@vger.kernel.org, pawel@osciak.com, Hans Verkuil Subject: Re: [REVIEW PATCH for v3.15 1/4] v4l2-subdev.h: fix sparse error with v4l2_subdev_notify References: <1394888883-46850-1-git-send-email-hverkuil@xs4all.nl> <1394888883-46850-2-git-send-email-hverkuil@xs4all.nl> <2510988.dElkAvpb7d@avalon> In-Reply-To: <2510988.dElkAvpb7d@avalon> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-media-owner@vger.kernel.org List-ID: On 03/17/2014 12:44 PM, Laurent Pinchart wrote: > Hi Hans, > > Thank you for the patch. > > On Saturday 15 March 2014 14:08:00 Hans Verkuil wrote: >> From: Hans Verkuil >> >> The notify function is a void function, yet the v4l2_subdev_notify >> define uses it in a ? : construction, which causes sparse warnings. >> >> Signed-off-by: Hans Verkuil >> --- >> include/media/v4l2-subdev.h | 8 +++++--- >> 1 file changed, 5 insertions(+), 3 deletions(-) >> >> diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h >> index 28f4d8c..0fbf669 100644 >> --- a/include/media/v4l2-subdev.h >> +++ b/include/media/v4l2-subdev.h >> @@ -692,9 +692,11 @@ void v4l2_subdev_init(struct v4l2_subdev *sd, >> (sd)->ops->o->f((sd) , ##args) : -ENOIOCTLCMD)) >> >> /* Send a notification to v4l2_device. */ >> -#define v4l2_subdev_notify(sd, notification, arg) \ >> - ((!(sd) || !(sd)->v4l2_dev || !(sd)->v4l2_dev->notify) ? -ENODEV : \ >> - (sd)->v4l2_dev->notify((sd), (notification), (arg))) >> +#define v4l2_subdev_notify(sd, notification, arg) \ >> + do { \ >> + if ((sd) && (sd)->v4l2_dev && (sd)->v4l2_dev->notify) \ >> + (sd)->v4l2_dev->notify((sd), (notification), (arg)); \ >> + } while (0) > > The construct would prevent using v4l2_subdev_notify() as an expression. What > about turning the macro into an inline function instead ? How can you use a void function in an expression anyway? That was the whole point of the sparse error. Regards, Hans > >> #define v4l2_subdev_has_op(sd, o, f) \ >> ((sd)->ops->o && (sd)->ops->o->f) >