From patchwork Wed Jun 19 01:23:52 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Laurent Pinchart X-Patchwork-Id: 13703321 Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [213.167.242.64]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A83A5EAF9; Wed, 19 Jun 2024 01:24:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=213.167.242.64 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718760269; cv=none; b=RjZqmWykEHYrutbA5c9u2vJ6tPvER1ibE3VJ/+UZwU1utbGqSPFyWHNWy0Rh1Bgk03hZDxkixHiBqVdNDr+t4MqCU5n+wN6SVdlOKno7guf6xqG1xp+6QvWhYZdVv0P0fKM2Nr20E98IgeLCwgzC4Teu//6PND4uA1QHS9OZHY4= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718760269; c=relaxed/simple; bh=GebboEQBPNN6stBSyIeo/u+bZsCpoRVYWm0IsmkmX2g=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=V48IT5ecINQwUOhRJSNy1MtHtnkg5+JjGAvDD9tUD8HcWlsRgW1OShtZc7nc/+qd/w4qvdAAfkNNa7WFstirr9AhsVu5kf2kdyg/ywarTv+FeJkIzSXR7UxV/wIgCAZl9ZbQfiM1FNaqHtYVy3bHxgLLNCZLWxb8lGI2lsY8Trw= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=ideasonboard.com; spf=pass smtp.mailfrom=ideasonboard.com; dkim=pass (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b=SXVNE4PA; arc=none smtp.client-ip=213.167.242.64 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=ideasonboard.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=ideasonboard.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b="SXVNE4PA" Received: from pendragon.ideasonboard.com (81-175-209-231.bb.dnainternet.fi [81.175.209.231]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id 73294F89; Wed, 19 Jun 2024 03:24:06 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1718760246; bh=GebboEQBPNN6stBSyIeo/u+bZsCpoRVYWm0IsmkmX2g=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=SXVNE4PALmS+2/4h2cUercuGY/blGsocT1V8aXhkFV+mZGxDrEAPDhUgN/6DwcijD v1k+BJMVXizFpH+X8p47hU3HElgcN7+pwdOor0HTTSjrdKR8BIn1PDFOtEPJUNmTUT hAilrrz7qbG1FYoi1qJIf90Y8eGeiskCLrp1D2sA= From: Laurent Pinchart To: linux-media@vger.kernel.org Cc: linux-renesas-soc@vger.kernel.org, linux-sunxi@lists.linux.dev, Eugen Hristev , Maxime Ripard , Chen-Yu Tsai , Sakari Ailus , Kieran Bingham , Tomi Valkeinen , Jacopo Mondi , Hans Verkuil Subject: [PATCH 4/8] media: v4l2-subdev: Refactor warnings in v4l2_subdev_link_validate() Date: Wed, 19 Jun 2024 04:23:52 +0300 Message-ID: <20240619012356.22685-5-laurent.pinchart+renesas@ideasonboard.com> X-Mailer: git-send-email 2.44.2 In-Reply-To: <20240619012356.22685-1-laurent.pinchart+renesas@ideasonboard.com> References: <20240619012356.22685-1-laurent.pinchart+renesas@ideasonboard.com> Precedence: bulk X-Mailing-List: linux-media@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 The v4l2_subdev_link_validate() function prints a one-time warning if it gets called on a link whose source or sink is not a subdev. As links get validated in the context of their sink, a call to the helper when the link's sink is not a subdev indicates that the driver has set its .link_validate() handler to v4l2_subdev_link_validate() on a non-subdev entity, which is a clear driver bug. On the other hand, the link's source not being a subdev indicates that the helper is used for a subdev connected to a video output device, which is a lesser issue, if only because this is currently common practice. There are no drivers left in the kernel that use v4l2_subdev_link_validate() in a context where it may get called on a non-subdev sink. Replace the pr_warn_once() with a WARN_ON() in this case to make sure that new offenders won't be introduced. Signed-off-by: Laurent Pinchart --- drivers/media/v4l2-core/v4l2-subdev.c | 14 +++++++++----- 1 file changed, 9 insertions(+), 5 deletions(-) diff --git a/drivers/media/v4l2-core/v4l2-subdev.c b/drivers/media/v4l2-core/v4l2-subdev.c index 4f71199bf592..2d5e39c79620 100644 --- a/drivers/media/v4l2-core/v4l2-subdev.c +++ b/drivers/media/v4l2-core/v4l2-subdev.c @@ -1451,11 +1451,15 @@ int v4l2_subdev_link_validate(struct media_link *link) bool states_locked; int ret; - if (!is_media_entity_v4l2_subdev(link->sink->entity) || - !is_media_entity_v4l2_subdev(link->source->entity)) { - pr_warn_once("%s of link '%s':%u->'%s':%u is not a V4L2 sub-device, driver bug!\n", - !is_media_entity_v4l2_subdev(link->sink->entity) ? - "sink" : "source", + /* + * Links are validated in the context of the sink entity. Usage of this + * helper on a sink that is not a subdev is a clear driver bug. + */ + if (WARN_ON(!is_media_entity_v4l2_subdev(link->sink->entity))) + return -EINVAL; + + if (!is_media_entity_v4l2_subdev(link->source->entity)) { + pr_warn_once("source of link '%s':%u->'%s':%u is not a V4L2 sub-device, driver bug!\n", link->source->entity->name, link->source->index, link->sink->entity->name, link->sink->index); return 0;