From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 19221C3A589 for ; Thu, 15 Aug 2019 13:09:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E95AB2083B for ; Thu, 15 Aug 2019 13:09:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732104AbfHONJ6 (ORCPT ); Thu, 15 Aug 2019 09:09:58 -0400 Received: from mga04.intel.com ([192.55.52.120]:15062 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730635AbfHONJ5 (ORCPT ); Thu, 15 Aug 2019 09:09:57 -0400 X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by fmsmga104.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 15 Aug 2019 06:09:57 -0700 X-IronPort-AV: E=Sophos;i="5.64,389,1559545200"; d="scan'208";a="194763653" Received: from paasikivi.fi.intel.com ([10.237.72.42]) by fmsmga001-auth.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 15 Aug 2019 06:09:55 -0700 Received: by paasikivi.fi.intel.com (Postfix, from userid 1000) id 426BB206FD; Thu, 15 Aug 2019 16:08:49 +0300 (EEST) Date: Thu, 15 Aug 2019 16:08:49 +0300 From: Sakari Ailus To: Laurent Pinchart Cc: Jacopo Mondi , Mauro Carvalho Chehab , Hans Verkuil , "open list:MEDIA INPUT INFRASTRUCTURE (V4L/DVB)" , open list Subject: Re: [RFC 2/5] media: v4l2-ctrl: Document V4L2_CID_LOCATION Message-ID: <20190815130849.GQ6133@paasikivi.fi.intel.com> References: <20190814202815.32491-1-jacopo@jmondi.org> <20190814202815.32491-3-jacopo@jmondi.org> <20190815070025.GK6133@paasikivi.fi.intel.com> <20190815125938.GI13823@pendragon.ideasonboard.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190815125938.GI13823@pendragon.ideasonboard.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Aug 15, 2019 at 03:59:38PM +0300, Laurent Pinchart wrote: > Hi Sakari, > > On Thu, Aug 15, 2019 at 10:00:25AM +0300, Sakari Ailus wrote: > > On Wed, Aug 14, 2019 at 10:28:12PM +0200, Jacopo Mondi wrote: > > > Add documentation for the V4L2_CID_LOCATION camera control. The newly > > > added read-only control reports the camera device mounting position. > > > > > > Signed-off-by: Jacopo Mondi > > > --- > > > .../media/uapi/v4l/ext-ctrls-camera.rst | 23 +++++++++++++++++++ > > > 1 file changed, 23 insertions(+) > > > > > > diff --git a/Documentation/media/uapi/v4l/ext-ctrls-camera.rst b/Documentation/media/uapi/v4l/ext-ctrls-camera.rst > > > index 51c1d5c9eb00..fc0a02eee6d4 100644 > > > --- a/Documentation/media/uapi/v4l/ext-ctrls-camera.rst > > > +++ b/Documentation/media/uapi/v4l/ext-ctrls-camera.rst > > > @@ -510,6 +510,29 @@ enum v4l2_scene_mode - > > > value down. A value of zero stops the motion if one is in progress > > > and has no effect otherwise. > > > > > > +``V4L2_CID_LOCATION (integer)`` > > > + This read-only control describes the camera location by reporting its > > > + mounting position on the device where the camera is installed. This > > > + control is particularly meaningful for devices which have a well defined > > > + orientation, such as phones, laptops and portable devices as the camera > > > + location is expressed as a position relative to the device intended > > > + usage position. In example, a camera installed on the user-facing side > > > > s/In/For/ > > > > > + of a phone device is said to be installed in the ``V4L2_LOCATION_FRONT`` > > > + position. > > > + > > > + > > > + > > > +.. flat-table:: > > > + :header-rows: 0 > > > + :stub-columns: 0 > > > + > > > + * - ``V4L2_LOCATION_FRONT`` > > > + - The camera device is located on the front side of the device. > > > + * - ``V4L2_LOCATION_BACK`` > > > + - The camera device is located on the back side of the device. > > > + > > > + > > > + > > > .. [#f1] > > > This control may be changed to a menu control in the future, if more > > > options are required. > > > > There's an effective limit of 64 for menus. ACPI has less than ten > > different locations for a device, I think 64 will be enough here. > > > > So I'd be actually in favour of switching to a menu. > > Why ? As you explained yourself, it's a static read-only control, all it > needs to report is a single value. Yes. That's true. It wasn't meant for this but it's nevertheless a convenient API to get that information, both as integer and string. -- Sakari Ailus sakari.ailus@linux.intel.com