From mboxrd@z Thu Jan 1 00:00:00 1970 From: Steve Longerbeam Subject: Re: [PATCH v4 14/36] [media] v4l2-mc: add a function to inherit controls from a pipeline Date: Thu, 2 Mar 2017 18:12:43 -0800 Message-ID: References: <1487211578-11360-1-git-send-email-steve_longerbeam@mentor.com> <1487211578-11360-15-git-send-email-steve_longerbeam@mentor.com> <20170302160257.GK3220@valkosipuli.retiisi.org.uk> <141eb012-eb24-7558-2bc5-1fe82f6b7b4b@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <141eb012-eb24-7558-2bc5-1fe82f6b7b4b@gmail.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: driverdev-devel-bounces@linuxdriverproject.org Sender: "devel" To: Sakari Ailus Cc: mark.rutland@arm.com, andrew-ct.chen@mediatek.com, minghsiu.tsai@mediatek.com, sakari.ailus@linux.intel.com, nick@shmanahar.org, songjun.wu@microchip.com, hverkuil@xs4all.nl, Steve Longerbeam , pavel@ucw.cz, robert.jarzmik@free.fr, devel@driverdev.osuosl.org, markus.heiser@darmarIT.de, laurent.pinchart+renesas@ideasonboard.com, shuah@kernel.org, linux@armlinux.org.uk, geert@linux-m68k.org, linux-media@vger.kernel.org, devicetree@vger.kernel.org, kernel@pengutronix.de, arnd@arndb.de, mchehab@kernel.org, bparrot@ti.com, robh+dt@kernel.org, horms+renesas@verge.net.au, tiffany.lin@mediatek.com, linux-arm-kernel@lists.infradead.org, niklas.soderlund+renesas@ragnatech.se, gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org, jean-christophe.trotin@st.com, p.zabel@pengutronix.de, fabio.estevam@nxp.com, shawnguo@kernel.org, sudipm.mukherjee@gmail List-Id: devicetree@vger.kernel.org On 03/02/2017 03:48 PM, Steve Longerbeam wrote: > > > On 03/02/2017 08:02 AM, Sakari Ailus wrote: >> Hi Steve, >> >> On Wed, Feb 15, 2017 at 06:19:16PM -0800, Steve Longerbeam wrote: >>> v4l2_pipeline_inherit_controls() will add the v4l2 controls from >>> all subdev entities in a pipeline to a given video device. >>> >>> Signed-off-by: Steve Longerbeam >>> --- >>> drivers/media/v4l2-core/v4l2-mc.c | 48 >>> +++++++++++++++++++++++++++++++++++++++ >>> include/media/v4l2-mc.h | 25 ++++++++++++++++++++ >>> 2 files changed, 73 insertions(+) >>> >>> diff --git a/drivers/media/v4l2-core/v4l2-mc.c >>> b/drivers/media/v4l2-core/v4l2-mc.c >>> index 303980b..09d4d97 100644 >>> --- a/drivers/media/v4l2-core/v4l2-mc.c >>> +++ b/drivers/media/v4l2-core/v4l2-mc.c >>> @@ -22,6 +22,7 @@ >>> #include >>> #include >>> #include >>> +#include >>> #include >>> #include >>> #include >>> @@ -238,6 +239,53 @@ int v4l_vb2q_enable_media_source(struct >>> vb2_queue *q) >>> } >>> EXPORT_SYMBOL_GPL(v4l_vb2q_enable_media_source); >>> >>> +int __v4l2_pipeline_inherit_controls(struct video_device *vfd, >>> + struct media_entity *start_entity) >> >> I have a few concerns / questions: >> >> - What's the purpose of this patch? Why not to access the sub-device node >> directly? > > > I don't really understand what you are trying to say. > Actually I think I understand what you mean now. Yes, the user can always access a subdev's control directly from its /dev/v4l-subdevXX. I'm only providing this feature as a convenience to the user, so that all controls in a pipeline can be accessed from one place, i.e. the main capture device node. Steve