From patchwork Tue Nov 23 12:37:50 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hanlin Chen X-Patchwork-Id: 14707 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 56D8BBF415 for ; Tue, 23 Nov 2021 12:38:11 +0000 (UTC) Received: from lancelot.ideasonboard.com (localhost [IPv6:::1]) by lancelot.ideasonboard.com (Postfix) with ESMTP id DB75960398; Tue, 23 Nov 2021 13:38:10 +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="oD+AmyG6"; dkim-atps=neutral Received: from mail-pf1-x42f.google.com (mail-pf1-x42f.google.com [IPv6:2607:f8b0:4864:20::42f]) by lancelot.ideasonboard.com (Postfix) with ESMTPS id 035BE60398 for ; Tue, 23 Nov 2021 13:38:08 +0100 (CET) Received: by mail-pf1-x42f.google.com with SMTP id n26so19322886pff.3 for ; Tue, 23 Nov 2021 04:38:07 -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=CD0u+dZO4p2XssMpLn5qa6N9zSQYWtS1JAmrhwOI/kU=; b=oD+AmyG639vMrJ65dyBlbasf2EXV2IMMmwFSCCqDpLrV4BBDiUd0VPWGM+838qnZTX 95mkixYila7tnFZh7xJZ11xhv8saJK07Wa9qSV74uHNoufJ1hXkJL9KnG83QdicgUxlA f0tWD17dHj0vpp3xFiMIa/XbDAAGBDI4Ao/KE= 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=CD0u+dZO4p2XssMpLn5qa6N9zSQYWtS1JAmrhwOI/kU=; b=kWVSzAC6pm6K/EVf9RDu0bIg2y0riTFPoXkSQ/0vLbQ325Rx4qU6poHejKujfIx26H SFHm1NpYMRCWpaiAADJiYHPR1qFOfymwmDeTcC1YOCwQJpbYdUdSnFx4FInlLh0D9TSr ufABWUsHmCACTfqDFfECR9npZs7rq/tGf0dfgSz7qm+gTZOlb8+mj3t0tPc9R05btOhp rLaPuUdfcxd/bFaU/BL6LWnuat1Avs4HBGb/Ao924my8sDGVg1YZ9VFJ7ePuTUOB1VzF XNv7/bHLWE9HU8osRHgL2i5ATatob3u9vAZlHHtzmxpRgyLRj0WB0fd5YLryoNWp0NbK Gxkw== X-Gm-Message-State: AOAM533B1wW82d1+7G6IXCJzAq47Sxkbdw4XV6hpkB4L7KIZDBkxRTxB MsdaQXhNHKCK0L/zBU++OAgh81jrhpQ5KA== X-Google-Smtp-Source: ABdhPJzYiD+guD5Jb6PGZhtDZ+twcG1KMSdUSDx471tx4mFb5KDwHJGSyjWvfTInN9suNESS/gViBQ== X-Received: by 2002:a65:5ccb:: with SMTP id b11mr3616462pgt.408.1637671086228; Tue, 23 Nov 2021 04:38:06 -0800 (PST) Received: from localhost ([2401:fa00:1:10:8aa3:febd:fadf:4199]) by smtp.gmail.com with UTF8SMTPSA id j6sm12860904pfu.205.2021.11.23.04.38.05 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 23 Nov 2021 04:38:05 -0800 (PST) From: Han-Lin Chen To: libcamera-devel@lists.libcamera.org Date: Tue, 23 Nov 2021 20:37:50 +0800 Message-Id: <20211123123751.3194696-4-hanlinchen@chromium.org> X-Mailer: git-send-email 2.34.0.rc2.393.gf8c9666880-goog In-Reply-To: <20211123123751.3194696-1-hanlinchen@chromium.org> References: <20211123123751.3194696-1-hanlinchen@chromium.org> MIME-Version: 1.0 Subject: [libcamera-devel] [PATCH v4 3/4] 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 --- Documentation/index.rst | 1 + Documentation/lens_driver_requirements.rst | 28 ++++ Documentation/meson.build | 1 + include/libcamera/internal/camera_lens.h | 48 +++++++ include/libcamera/internal/meson.build | 1 + src/libcamera/camera_lens.cpp | 150 +++++++++++++++++++++ src/libcamera/meson.build | 1 + 7 files changed, 230 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..afc300cf --- /dev/null +++ b/Documentation/lens_driver_requirements.rst @@ -0,0 +1,28 @@ +.. 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 one or multiple sub-devices exposed in 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..fe83d4ad --- /dev/null +++ b/include/libcamera/internal/camera_lens.h @@ -0,0 +1,48 @@ +/* SPDX-License-Identifier: LGPL-2.1-or-later */ +/* + * Copyright (C) 2021, Google Inc. + * + * camera_lens.h - A camera lens + */ +#ifndef __LIBCAMERA_INTERNAL_CAMERA_LENS_H__ +#define __LIBCAMERA_INTERNAL_CAMERA_LENS_H__ + +#include +#include + +#include + +#include "libcamera/internal/v4l2_subdevice.h" + +namespace libcamera { + +class MediaEntity; + +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 */ + +#endif /* __LIBCAMERA_INTERNAL_CAMERA_LENS_H__ */ diff --git a/include/libcamera/internal/meson.build b/include/libcamera/internal/meson.build index de8630fe..7e9b9998 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', 'camera_utils.h', diff --git a/src/libcamera/camera_lens.cpp b/src/libcamera/camera_lens.cpp new file mode 100644 index 00000000..cb7159fe --- /dev/null +++ b/src/libcamera/camera_lens.cpp @@ -0,0 +1,150 @@ +/* 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 + +#include "libcamera/internal/camera_utils.h" +#include "libcamera/internal/media_device.h" +#include "libcamera/internal/sysfs.h" + +/** + * \file camera_lens.h + * \brief A camera lens + */ + +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. + * + * The implementation is currently limited to lens that expose a single V4L2 + * subdevice. It will be extended to support more complex devices as the needs + * arise. + */ + +/** + * \brief Construct a CameraLens + * \param[in] entity The media entity backing the camera lens + * + * 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; + } + + model_ = extractModelFromEntityName(entity_->name()); + + /* 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; + + 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 err = 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"; + err = -EINVAL; + } + } + + if (err) { + 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 err; + } + + return 0; +} + +/** + * \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 563ed861..2100805d 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',