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Date:   Wed, 12 Apr 2023 14:50:18 +0300
From:   Sakari Ailus <sakari.ailus@linux.intel.com>
To:     Michael Riesch <michael.riesch@wolfvision.net>
Cc:     Dave Stevenson <dave.stevenson@raspberrypi.com>,
        Mauro Carvalho Chehab <mchehab@kernel.org>,
        Michael Riesch via B4 Relay 
        <devnull+michael.riesch.wolfvision.net@kernel.org>,
        linux-kernel@vger.kernel.org,
        Matthias Fend <Matthias.Fend@wolfvision.net>,
        libcamera-devel@lists.libcamera.org, linux-media@vger.kernel.org
Subject: Re: [libcamera-devel] [PATCH RFC 1/4] media: v4l2-ctrls: add lens
 group status controls for zoom and focus
Message-ID: <ZDaa+qhoZxZ5ymxL@kekkonen.localdomain>
References: <20230406-feature-controls-lens-v1-0-543189a680de@wolfvision.net>
 <20230406-feature-controls-lens-v1-1-543189a680de@wolfvision.net>
 <CAPY8ntArOOqPQzvkJrQEyuVFfb6j8x6WODTMHOn1qHPU588mbQ@mail.gmail.com>
 <0f1baf5e-2ff6-e10b-5c3e-0a82c71d0ce6@wolfvision.net>
 <CAPY8ntAjBEFfeV6nnQs34Y22QM-irT13ALDv4ksP8AYK=jWsKg@mail.gmail.com>
 <3ab7bfc4-aaae-2e39-b420-40ad8d71dda4@wolfvision.net>
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Hi Michael,

On Wed, Apr 12, 2023 at 10:00:26AM +0200, Michael Riesch wrote:
>  - Different controls: If moving = (V4L2_CID_FOCUS_ABSOLUTE == current),
>    then what happens if the application performs a
>    V4L2_CID_FOCUS_RELATIVE with -3? current should reach 39,
>    V4L2_CID_FOCUS_ABSOLUTE is still at 42, the lens is still moving from
>    the application's point of view.

Would there be a reason to implement both of these controls in a single
driver? AFAIU, the relative one should be used if there absolute value
isn't known to the driver.

-- 
Kind regards,

Sakari Ailus