From patchwork Tue Jan 19 14:37:02 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jacopo Mondi X-Patchwork-Id: 10890 X-Patchwork-Delegate: jacopo@jmondi.org Return-Path: X-Original-To: parsemail@patchwork.libcamera.org Delivered-To: parsemail@patchwork.libcamera.org Received: from lancelot.ideasonboard.com (lancelot.ideasonboard.com [92.243.16.209]) by patchwork.libcamera.org (Postfix) with ESMTPS id B6A23BD808 for ; Tue, 19 Jan 2021 14:37:00 +0000 (UTC) Received: from lancelot.ideasonboard.com (localhost [IPv6:::1]) by lancelot.ideasonboard.com (Postfix) with ESMTP id 8A9406815A; Tue, 19 Jan 2021 15:37:00 +0100 (CET) Received: from relay6-d.mail.gandi.net (relay6-d.mail.gandi.net [217.70.183.198]) by lancelot.ideasonboard.com (Postfix) with ESMTPS id 0AE9568140 for ; Tue, 19 Jan 2021 15:36:58 +0100 (CET) X-Originating-IP: 93.61.96.190 Received: from uno.LocalDomain (93-61-96-190.ip145.fastwebnet.it [93.61.96.190]) (Authenticated sender: jacopo@jmondi.org) by relay6-d.mail.gandi.net (Postfix) with ESMTPSA id AF004C001E for ; Tue, 19 Jan 2021 14:36:57 +0000 (UTC) From: Jacopo Mondi To: libcamera-devel@lists.libcamera.org Date: Tue, 19 Jan 2021 15:37:02 +0100 Message-Id: <20210119143711.153517-3-jacopo@jmondi.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20210119143711.153517-1-jacopo@jmondi.org> References: <20210119143711.153517-1-jacopo@jmondi.org> MIME-Version: 1.0 Subject: [libcamera-devel] [PATCH v2 02/11] libcamera: camera_sensor: Make V4L2_CID_EXPOSURE mandatory X-BeenThere: libcamera-devel@lists.libcamera.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: libcamera-devel-bounces@lists.libcamera.org Sender: "libcamera-devel" Add the V4L2_CID_EXPOSURE control to the list of mandatory controls the sensor driver has to report and document this new requirement. While at it, re-sort the mandatory V4L2 controls in alphabetical order in the CameraSensor class. Reviewed-by: Laurent Pinchart Signed-off-by: Jacopo Mondi --- Documentation/sensor_driver_requirements.rst | 11 ++++++++++- src/libcamera/camera_sensor.cpp | 3 ++- 2 files changed, 12 insertions(+), 2 deletions(-) diff --git a/Documentation/sensor_driver_requirements.rst b/Documentation/sensor_driver_requirements.rst index 0e658aaa03b5..187f1c921dbf 100644 --- a/Documentation/sensor_driver_requirements.rst +++ b/Documentation/sensor_driver_requirements.rst @@ -24,13 +24,22 @@ The sensor driver is assumed to be fully compliant with the V4L2 specification. The sensor driver shall support the following V4L2 controls: +* `V4L2_CID_EXPOSURE`_ * `V4L2_CID_HBLANK`_ * `V4L2_CID_PIXEL_RATE`_ +.. _V4L2_CID_EXPOSURE: https://www.kernel.org/doc/html/latest/userspace-api/media/v4l/control.html .. _V4L2_CID_HBLANK: https://www.kernel.org/doc/html/latest/userspace-api/media/v4l/ext-ctrls-image-source.html .. _V4L2_CID_PIXEL_RATE: https://www.kernel.org/doc/html/latest/userspace-api/media/v4l/ext-ctrls-image-process.html -Both controls are used to compute the sensor output timings. +The `EXPOSURE` control shall report the image integration time in number of +lines. While V4L2 doesn't specify a unit for the `EXPOSURE` control, libcamera +requires it to be expressed as a number of image lines. Camera sensor drivers +that do not comply with this requirement will need to be adapted or will produce +incorrect results. + +The `HBLANK` and `PIXEL_RATE` controls are used to compute the sensor output +timings. Optional Requirements --------------------- diff --git a/src/libcamera/camera_sensor.cpp b/src/libcamera/camera_sensor.cpp index 9abb9d330664..5774578fe61f 100644 --- a/src/libcamera/camera_sensor.cpp +++ b/src/libcamera/camera_sensor.cpp @@ -243,8 +243,9 @@ int CameraSensor::validateSensorDriver() * - V4L2_CID_HBLANK is used to calculate the line length */ const std::vector mandatoryControls{ - V4L2_CID_PIXEL_RATE, + V4L2_CID_EXPOSURE, V4L2_CID_HBLANK, + V4L2_CID_PIXEL_RATE, }; ControlList ctrls = subdev_->getControls(mandatoryControls);