From patchwork Thu Dec 2 14:03:15 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hanlin Chen X-Patchwork-Id: 14991 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 75D6EBF415 for ; Thu, 2 Dec 2021 14:03:33 +0000 (UTC) Received: from lancelot.ideasonboard.com (localhost [IPv6:::1]) by lancelot.ideasonboard.com (Postfix) with ESMTP id 2B7C56011A; Thu, 2 Dec 2021 15:03:33 +0100 (CET) Authentication-Results: lancelot.ideasonboard.com; dkim=fail reason="signature verification failed" (1024-bit key; unprotected) header.d=chromium.org header.i=@chromium.org header.b="PLOUNRaG"; dkim-atps=neutral Received: from mail-pl1-x62b.google.com (mail-pl1-x62b.google.com [IPv6:2607:f8b0:4864:20::62b]) by lancelot.ideasonboard.com (Postfix) with ESMTPS id C69956011A for ; Thu, 2 Dec 2021 15:03:31 +0100 (CET) Received: by mail-pl1-x62b.google.com with SMTP id z6so20297244plk.6 for ; Thu, 02 Dec 2021 06:03:31 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=OJ63cKZP+EAGTa4hwAstFtBGEEx2PmjCe6CbWfZO8eI=; b=PLOUNRaGfcB4Xfyn1610TxhTJKrkAP1O6H1zFxfJgHLHFMe/t17e05ugKGeRrIoURl PtU0qmDnPW2bcrk+1WomBw+/+x8mkCnyL4j35tVTJedZ0lhAfzdPQa0KfyIWrd9HaaIC pDKBEahjt0EA4sQUISqf3wqwVH7wkHl5vPQIs= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=OJ63cKZP+EAGTa4hwAstFtBGEEx2PmjCe6CbWfZO8eI=; b=7y3TUS1WHGAgDf40xUzKnvypPDEtaDH36FK6HuSbjfdi3211XtLg+tOD/RRe4qUfRJ Q3u4GpzbAoACcbL5KkHCCSmUZaLDj+z9IWtAoHNDvDFk7V/u6CG8BcRA9hw0NDmtzG42 v2MdJKxMr2EM8hxtpsr7MpMAzwlY3c3deLD7n1CaS5KTj/S8s81ikTAfwcWh9dSSqnMo YvgK6SKXuGnc6Iuty6TSCTZUbhl+jW5NpKda4K9I9JjfNGonvQS+MVzsOCtoHaatQFx6 1YzaoSe90ikhjPlLtlydUXWsOnCssM4W3Hs2enBB2fI9u0TiACc0RG9DItgzjrMU/LqB pbaA== X-Gm-Message-State: AOAM5303t7WRxc0nECdPIZ7/PKNUKAKZ2LxFHBoOCURR4Ry6Zw8A40Nj 0q8oeZbcoEZXsnvJKf/+pPGVe0Ibw4NhZQ== X-Google-Smtp-Source: ABdhPJz+cJxy1AXsKZ4awMrwWP0WkJP0SllQ7zhYLZatHflqiRDgtt5yd682Cl1cnoghE6SxLNypRw== X-Received: by 2002:a17:90a:df14:: with SMTP id gp20mr6235775pjb.186.1638453809944; Thu, 02 Dec 2021 06:03:29 -0800 (PST) Received: from localhost ([2401:fa00:1:10:9029:d68:4045:e723]) by smtp.gmail.com with UTF8SMTPSA id p6sm2799505pjb.48.2021.12.02.06.03.28 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 02 Dec 2021 06:03:29 -0800 (PST) From: Han-Lin Chen To: libcamera-devel@lists.libcamera.org Date: Thu, 2 Dec 2021 22:03:15 +0800 Message-Id: <20211202140317.3118364-4-hanlinchen@chromium.org> X-Mailer: git-send-email 2.34.1.400.ga245620fadb-goog In-Reply-To: <20211202140317.3118364-1-hanlinchen@chromium.org> References: <20211202140317.3118364-1-hanlinchen@chromium.org> MIME-Version: 1.0 Subject: [libcamera-devel] [PATCH v7 3/5] libcamera: camera_lens: Add a new class to model a camera lens 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" The CameraLens class abstracts camera lens and provides helper functions to ease interactions with them. Signed-off-by: Han-Lin Chen Reviewed-by: Kieran Bingham Reviewed-by: Laurent Pinchart Reviewed-by: Umang Jain --- Documentation/index.rst | 1 + Documentation/lens_driver_requirements.rst | 27 ++++ Documentation/meson.build | 1 + include/libcamera/internal/camera_lens.h | 45 +++++++ include/libcamera/internal/meson.build | 1 + src/libcamera/camera_lens.cpp | 142 +++++++++++++++++++++ src/libcamera/meson.build | 1 + 7 files changed, 218 insertions(+) create mode 100644 Documentation/lens_driver_requirements.rst create mode 100644 include/libcamera/internal/camera_lens.h create mode 100644 src/libcamera/camera_lens.cpp diff --git a/Documentation/index.rst b/Documentation/index.rst index 1f4fc485..0ee10044 100644 --- a/Documentation/index.rst +++ b/Documentation/index.rst @@ -21,3 +21,4 @@ Tracing guide Environment variables Sensor driver requirements + Lens driver requirements diff --git a/Documentation/lens_driver_requirements.rst b/Documentation/lens_driver_requirements.rst new file mode 100644 index 00000000..b96e502d --- /dev/null +++ b/Documentation/lens_driver_requirements.rst @@ -0,0 +1,27 @@ +.. SPDX-License-Identifier: CC-BY-SA-4.0 + +.. _lens-driver-requirements: + +Lens Driver Requirements +======================== + +libcamera handles lens devices in the CameraLens class and defines +a consistent interface through its API towards other library components. + +The CameraLens class uses the V4L2 subdev kernel API to interface with the +camera lens through a sub-device exposed to userspace by the lens driver. + +In order for libcamera to be fully operational and provide all the required +information to interface with the camera lens to applications and pipeline +handlers, a set of mandatory features the driver has to support has been defined. + +Mandatory Requirements +---------------------- + +The lens driver is assumed to be fully compliant with the V4L2 specification. + +The lens driver shall support the following V4L2 controls: + +* `V4L2_CID_FOCUS_ABSOLUTE`_ + +.. _V4L2_CID_FOCUS_ABSOLUTE: https://www.kernel.org/doc/html/latest/userspace-api/media/v4l/ext-ctrls-camera.html diff --git a/Documentation/meson.build b/Documentation/meson.build index 4c972675..33af82aa 100644 --- a/Documentation/meson.build +++ b/Documentation/meson.build @@ -66,6 +66,7 @@ if sphinx.found() 'guides/pipeline-handler.rst', 'guides/tracing.rst', 'index.rst', + 'lens_driver_requirements.rst', 'sensor_driver_requirements.rst', '../README.rst', ] diff --git a/include/libcamera/internal/camera_lens.h b/include/libcamera/internal/camera_lens.h new file mode 100644 index 00000000..6f2ea1bc --- /dev/null +++ b/include/libcamera/internal/camera_lens.h @@ -0,0 +1,45 @@ +/* SPDX-License-Identifier: LGPL-2.1-or-later */ +/* + * Copyright (C) 2021, Google Inc. + * + * camera_lens.h - A camera lens controller + */ +#pragma once + +#include +#include + +#include +#include + +namespace libcamera { + +class MediaEntity; +class V4L2Subdevice; + +class CameraLens : protected Loggable +{ +public: + explicit CameraLens(const MediaEntity *entity); + ~CameraLens(); + + int init(); + int setFocusPostion(int32_t position); + + const std::string &model() const { return model_; } + +protected: + std::string logPrefix() const override; + +private: + LIBCAMERA_DISABLE_COPY_AND_MOVE(CameraLens) + + int validateLensDriver(); + + const MediaEntity *entity_; + std::unique_ptr subdev_; + + std::string model_; +}; + +} /* namespace libcamera */ diff --git a/include/libcamera/internal/meson.build b/include/libcamera/internal/meson.build index 665fd6de..a96bbb95 100644 --- a/include/libcamera/internal/meson.build +++ b/include/libcamera/internal/meson.build @@ -14,6 +14,7 @@ libcamera_internal_headers = files([ 'byte_stream_buffer.h', 'camera.h', 'camera_controls.h', + 'camera_lens.h', 'camera_sensor.h', 'camera_sensor_properties.h', 'control_serializer.h', diff --git a/src/libcamera/camera_lens.cpp b/src/libcamera/camera_lens.cpp new file mode 100644 index 00000000..189cb025 --- /dev/null +++ b/src/libcamera/camera_lens.cpp @@ -0,0 +1,142 @@ +/* SPDX-License-Identifier: LGPL-2.1-or-later */ +/* + * Copyright (C) 2021, Google Inc. + * + * camera_lens.cpp - A camera lens + */ + +#include "libcamera/internal/camera_lens.h" + +#include + +#include "libcamera/internal/v4l2_subdevice.h" + +/** + * \file camera_lens.h + * \brief A camera lens controller + */ + +namespace libcamera { + +LOG_DEFINE_CATEGORY(CameraLens) + +/** + * \class CameraLens + * \brief A camera lens based on V4L2 subdevices + * + * The CameraLens class eases handling of lens for pipeline handlers by + * hiding the details of the V4L2 subdevice kernel API and caching lens + * information. + */ + +/** + * \brief Construct a CameraLens + * \param[in] entity The media entity backing the camera lens controller + * + * Once constructed the instance must be initialized with init(). + */ +CameraLens::CameraLens(const MediaEntity *entity) + : entity_(entity) +{ +} + +/** + * \brief Destroy a CameraLens + */ +CameraLens::~CameraLens() = default; + +/** + * \brief Initialize the camera lens instance + * + * This function performs the initialisation steps of the CameraLens that may + * fail. It shall be called once and only once after constructing the instance. + * + * \return 0 on success or a negative error code otherwise + */ +int CameraLens::init() +{ + if (entity_->function() != MEDIA_ENT_F_LENS) { + LOG(CameraLens, Error) + << "Invalid lens function " + << utils::hex(entity_->function()); + return -EINVAL; + } + + /* Create and open the subdev. */ + subdev_ = std::make_unique(entity_); + int ret = subdev_->open(); + if (ret < 0) + return ret; + + ret = validateLensDriver(); + if (ret) + return ret; + + model_ = subdev_->model(); + return 0; +} + +/** + * \brief This function sets the focal point of the lens to a specific position. + * \param[in] position The focal point of the lens + * + * This function sets the value of focal point of the lens as in \a position. + * + * \return 0 on success or -EINVAL otherwise + */ +int CameraLens::setFocusPostion(int32_t position) +{ + ControlList lensCtrls(subdev_->controls()); + lensCtrls.set(V4L2_CID_FOCUS_ABSOLUTE, static_cast(position)); + + if (subdev_->setControls(&lensCtrls)) + return -EINVAL; + + return 0; +} + +int CameraLens::validateLensDriver() +{ + int ret = 0; + static constexpr uint32_t mandatoryControls[] = { + V4L2_CID_FOCUS_ABSOLUTE, + }; + + const ControlInfoMap &controls = subdev_->controls(); + for (uint32_t ctrl : mandatoryControls) { + if (!controls.count(ctrl)) { + LOG(CameraLens, Error) + << "Mandatory V4L2 control " << utils::hex(ctrl) + << " not available"; + ret = -EINVAL; + } + } + + if (ret) { + LOG(CameraLens, Error) + << "The lens kernel driver needs to be fixed"; + LOG(CameraLens, Error) + << "See Documentation/lens_driver_requirements.rst in" + << " the libcamera sources for more information"; + return ret; + } + + return ret; +} + +/** + * \fn CameraLens::model() + * \brief Retrieve the lens model name + * + * The lens model name is a free-formed string that uniquely identifies the + * lens model. + * + * \return The lens model name + */ + +std::string CameraLens::logPrefix() const +{ + return "'" + entity_->name() + "'"; +} + +} /* namespace libcamera */ diff --git a/src/libcamera/meson.build b/src/libcamera/meson.build index 6727a777..3bee8fee 100644 --- a/src/libcamera/meson.build +++ b/src/libcamera/meson.build @@ -5,6 +5,7 @@ libcamera_sources = files([ 'byte_stream_buffer.cpp', 'camera.cpp', 'camera_controls.cpp', + 'camera_lens.cpp', 'camera_manager.cpp', 'camera_sensor.cpp', 'camera_sensor_properties.cpp',