{"id":24265,"url":"https://patchwork.libcamera.org/api/patches/24265/?format=json","web_url":"https://patchwork.libcamera.org/patch/24265/","project":{"id":1,"url":"https://patchwork.libcamera.org/api/projects/1/?format=json","name":"libcamera","link_name":"libcamera","list_id":"libcamera_core","list_email":"libcamera-devel@lists.libcamera.org","web_url":"","scm_url":"","webscm_url":""},"msgid":"<20250829-v4l2-params-v1-1-340773fb69ff@ideasonboard.com>","date":"2025-08-29T11:53:58","name":"[1/4] include: linux: Add v4l2-extensible-params.h","commit_ref":null,"pull_url":null,"state":"superseded","archived":false,"hash":"188689b7887f439425622e9d4aeae97da9440e9f","submitter":{"id":143,"url":"https://patchwork.libcamera.org/api/people/143/?format=json","name":"Jacopo Mondi","email":"jacopo.mondi@ideasonboard.com"},"delegate":null,"mbox":"https://patchwork.libcamera.org/patch/24265/mbox/","series":[{"id":5413,"url":"https://patchwork.libcamera.org/api/series/5413/?format=json","web_url":"https://patchwork.libcamera.org/project/libcamera/list/?series=5413","date":"2025-08-29T11:53:57","name":"ipa: libipa: Introduce V4L2Params","version":1,"mbox":"https://patchwork.libcamera.org/series/5413/mbox/"}],"comments":"https://patchwork.libcamera.org/api/patches/24265/comments/","check":"pending","checks":"https://patchwork.libcamera.org/api/patches/24265/checks/","tags":{},"headers":{"Return-Path":"","X-Original-To":"parsemail@patchwork.libcamera.org","Delivered-To":"parsemail@patchwork.libcamera.org","Received":["from lancelot.ideasonboard.com (lancelot.ideasonboard.com\n\t[92.243.16.209])\n\tby patchwork.libcamera.org (Postfix) with ESMTPS id 52D92BD87C\n\tfor ;\n\tFri, 29 Aug 2025 11:54:30 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id D0F9069328;\n\tFri, 29 Aug 2025 13:54:28 +0200 (CEST)","from perceval.ideasonboard.com (perceval.ideasonboard.com\n\t[213.167.242.64])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTPS id CD2FF692F1\n\tfor ;\n\tFri, 29 Aug 2025 13:54:23 +0200 (CEST)","from [192.168.1.102] (93-61-96-190.ip145.fastwebnet.it\n\t[93.61.96.190])\n\tby perceval.ideasonboard.com (Postfix) with ESMTPSA id 8C2CF4AF1;\n\tFri, 29 Aug 2025 13:53:18 +0200 (CEST)"],"Authentication-Results":"lancelot.ideasonboard.com; dkim=pass (1024-bit key;\n\tunprotected) header.d=ideasonboard.com header.i=@ideasonboard.com\n\theader.b=\"mB2bij+U\"; dkim-atps=neutral","DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com;\n\ts=mail; t=1756468398;\n\tbh=Xxs4zUCLpQHSbiJMe2xa6Brcir/RrSeEpTPGcLkb9pI=;\n\th=From:Date:Subject:References:In-Reply-To:To:Cc:From;\n\tb=mB2bij+U8B5xkFg26qopvwzssWiOJG1xu9KqQHaG1QFMYRDJLpoYT6CgHz05XS6ak\n\tGe8RWutX7RTWS5kk8m2Caiy8edOtcyErGAf0BYq1KPAxreFrfe0gXNVT4b/kTAfZRy\n\tMr6c7CGiTWML7seLv+GvQcDaz/mC0CwAbblJYSEc=","From":"Jacopo Mondi ","Date":"Fri, 29 Aug 2025 13:53:58 +0200","Subject":"[PATCH 1/4] include: linux: Add v4l2-extensible-params.h","MIME-Version":"1.0","Content-Type":"text/plain; charset=\"utf-8\"","Content-Transfer-Encoding":"7bit","Message-Id":"<20250829-v4l2-params-v1-1-340773fb69ff@ideasonboard.com>","References":"<20250829-v4l2-params-v1-0-340773fb69ff@ideasonboard.com>","In-Reply-To":"<20250829-v4l2-params-v1-0-340773fb69ff@ideasonboard.com>","To":"libcamera-devel@lists.libcamera.org","Cc":"Jacopo Mondi ","X-Mailer":"b4 0.14.2","X-Developer-Signature":"v=1; a=openpgp-sha256; l=7499;\n\ti=jacopo.mondi@ideasonboard.com; h=from:subject:message-id;\n\tbh=Xxs4zUCLpQHSbiJMe2xa6Brcir/RrSeEpTPGcLkb9pI=;\n\tb=owEBbQKS/ZANAwAKAXI0Bo8WoVY8AcsmYgBosZTuEc0x9eLC6nyHQnCCB4q33G+uXkn1AFJCz\n\tg3N1xkd/yCJAjMEAAEKAB0WIQS1xD1IgJogio9YOMByNAaPFqFWPAUCaLGU7gAKCRByNAaPFqFW\n\tPEchD/4tKaz17qlzXPboJuCwW9n3996o8a+GJ/DeuoTPYmOagmE8Ee/wVaVnTIOIn1IeKXhEOJ7\n\tCz16sAwI94svHcmepTB/zV9JsOabOiORFaakJ7mPbqZxCV8bp2FX+gSc8TRx0M8ctBJQH95oSGt\n\tT+7505rrrBtqdEtT3lBMPDchRsd0H8wsP+b151BC3axFVQh2gsf8j3bZ2VTn3RL2zQeOvY/ecS9\n\teDaLDhBKFQCqt4ZD2/5vVUON3wXoI5GnjVX7yQIINeUG6dSrtjbFqt0mn+W0tWwR4ZeyAuin4PL\n\tanhzQb/ffMR1dGWe/BNVTVYVZTuqnNdZFKEVzzEzob8B+8StEfM5/R2pa2PgSygvqpVWnB5cpv1\n\tkvy4rR5S1atR8riRV7EQF0j0A4pMC6+k36JTma9wm9CB2xYIQDMkyWJJv5oZgTsRzAOHxF9F7tb\n\tWeO7b107J+l1RiDmLmD9vt83oEybTCtb0OJ0QS7lI5sjliOa4GNz5pAZjcZ2RGQNm6TUIFvOq3Z\n\tS98e6CyIUkR6XxSIALNZ9sjy0dOFuKPHa7zgjWnT2RsVywUErYOasD0c8CqIwNyNtjHsJOCY0Uf\n\tJzUdRUVken8jqU4eLyH8yCLRAp/d5n6K1cxFohSLCJJUFVG1MqTpPwnD+itUqpHQZbu4fj26y42\n\tLqJrOELN9B2hpyg==","X-Developer-Key":"i=jacopo.mondi@ideasonboard.com; a=openpgp;\n\tfpr=72392EDC88144A65C701EA9BA5826A2587AD026B","X-BeenThere":"libcamera-devel@lists.libcamera.org","X-Mailman-Version":"2.1.29","Precedence":"list","List-Id":"","List-Unsubscribe":",\n\t","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n\t","Errors-To":"libcamera-devel-bounces@lists.libcamera.org","Sender":"\"libcamera-devel\" "},"content":"Import the v4l2-extensible-params.h header from the Linux\nkernel sources.\n\nThe file has not been merged in mainline Linux yet but is available\nat:\nhttps://lore.kernel.org/all/20250820-extensible-parameters-validation-v4-0-30fe5a99cb1f@ideasonboard.com/\n\nCreate the include/linux/media/ directory so that header files\nexported from the kernel which include this file do not need\nto be adjusted when imported in libcamera.\n\nSigned-off-by: Jacopo Mondi \n---\n include/linux/media/v4l2-extensible-params.h | 144 +++++++++++++++++++++++++++\n 1 file changed, 144 insertions(+)","diff":"diff --git a/include/linux/media/v4l2-extensible-params.h b/include/linux/media/v4l2-extensible-params.h\nnew file mode 100644\nindex 0000000000000000000000000000000000000000..2b93b5b4c04b3d29ddb7d509b4cbde64238d8c20\n--- /dev/null\n+++ b/include/linux/media/v4l2-extensible-params.h\n@@ -0,0 +1,144 @@\n+/* SPDX-License-Identifier: ((GPL-2.0+ WITH Linux-syscall-note) OR MIT) */\n+/*\n+ * Video4Linux2 extensible configuration parameters base types\n+ *\n+ * Copyright (C) 2025 Ideas On Board Oy\n+ * Author: Jacopo Mondi \n+ */\n+\n+#ifndef _V4L2_PARAMS_H_\n+#define _V4L2_PARAMS_H_\n+\n+#include \n+\n+#define V4L2_PARAMS_FL_BLOCK_DISABLE\t(1U << 0)\n+#define V4L2_PARAMS_FL_BLOCK_ENABLE\t(1U << 1)\n+\n+/*\n+ * Reserve the first 8 bits for V4L2_PARAMS_FL_* flag. Platform-specific flags\n+ * should be defined as:\n+ * #define PLATFORM_SPECIFIC_FLAG0\t((1U << V4L2_PARAMS_FL_PLATFORM_FLAGS(0))\n+ * #define PLATFORM_SPECIFIC_FLAG1\t((1U << V4L2_PARAMS_FL_PLATFORM_FLAGS(1))\n+ */\n+#define V4L2_PARAMS_FL_PLATFORM_FLAGS(n)\t((n) << 8)\n+\n+/**\n+ * struct v4l2_params_block_header - V4L2 extensible parameters block header\n+ *\n+ * This structure represents the common part of all the ISP configuration\n+ * blocks. Each parameters block shall embed an instance of this structure type\n+ * as its first member, followed by the block-specific configuration data. The\n+ * driver inspects this common header to discern the block type and its size and\n+ * properly handle the block content by casting it to the correct block-specific\n+ * type.\n+ *\n+ * The @type field is one of the values enumerated by each platform-specific ISP\n+ * block types which specifies how the data should be interpreted by the driver.\n+ * The @size field specifies the size of the parameters block and is used by the\n+ * driver for validation purposes.\n+ *\n+ * The @flags field is a bitmask of per-block flags V4L2_PARAMS_FL_* and\n+ * platform-specific flags specified by the platform-specific header.\n+ *\n+ * Documentation of the platform-specific flags handling is specified by the\n+ * platform-specific block header type:\n+ *\n+ * - Rockchip RkISP1: :c:type:`rkisp1_ext_params_block_type`\n+ * - Amlogic C3: :c:type:`c3_isp_params_block_type`\n+ *\n+ * Userspace is responsible for correctly populating the parameters block header\n+ * fields (@type, @flags and @size) and the block-specific parameters.\n+ *\n+ * @type: The parameters block type (platform-specific)\n+ * @flags: A bitmask of block flags (platform-specific)\n+ * @size: Size (in bytes) of the parameters block, including this header\n+ */\n+struct v4l2_params_block_header {\n+\t__u16 type;\n+\t__u16 flags;\n+\t__u32 size;\n+} __attribute__((aligned(8)));\n+\n+/**\n+ * v4l2_params_buffer_size - Calculate size of v4l2_params_buffer for a platform\n+ *\n+ * Users of the v4l2 extensible parameters will have differing sized data arrays\n+ * depending on their specific parameter buffers. Drivers and userspace will\n+ * need to be able to calculate the appropriate size of the struct to\n+ * accommodate all ISP configuration blocks provided by the platform.\n+ * This macro provides a convenient tool for the calculation.\n+ *\n+ * Each driver shall provide a definition of their extensible parameters\n+ * implementation data buffer size. As an example:\n+ *\n+ * #define PLATFORM_BLOCKS_MAX_SIZE\t\t\\\n+ *\tsizeof(platform_block_0)\t+\t\\\n+ *\tsizeof(platform_block_1)\n+ *\n+ * #define PLATFORM_BUFFER_SIZE\t\t\t\\\n+ *\tv4l2_params_buffer_size(PLATFORM_BLOCKS_MAX_SIZE)\n+ *\n+ * Drivers are then responsible for allocating buffers of the proper size\n+ * by assigning PLATFORM_BUFFER_SIZE to the per-plane size of the videobuf2\n+ * .queue_setup() operation and userspace shall use PLATFORM_BUFFER_SIZE\n+ * when populating the ISP configuration data buffer.\n+ *\n+ * @max_params_size: The total size of the ISP configuration blocks\n+ */\n+#define v4l2_params_buffer_size(max_params_size) \\\n+\t(offsetof(struct v4l2_params_buffer, data) + (max_params_size))\n+\n+/**\n+ * struct v4l2_params_buffer - V4L2 extensible parameters configuration\n+ *\n+ * This struct contains the configuration parameters of the ISP algorithms,\n+ * serialized by userspace into a data buffer. Each configuration parameter\n+ * block is represented by a block-specific structure which contains a\n+ * :c:type:`v4l2_params_block_header` entry as first member. Userspace populates\n+ * the @data buffer with configuration parameters for the blocks that it intends\n+ * to configure. As a consequence, the data buffer effective size changes\n+ * according to the number of ISP blocks that userspace intends to configure and\n+ * is set by userspace in the @data_size field.\n+ *\n+ * The parameters buffer is versioned by the @version field to allow modifying\n+ * and extending its definition. Userspace shall populate the @version field to\n+ * inform the driver about the version it intends to use. The driver will parse\n+ * and handle the @data buffer according to the data layout specific to the\n+ * indicated version and return an error if the desired version is not\n+ * supported.\n+ *\n+ * For each ISP block that userspace wants to configure, a block-specific\n+ * structure is appended to the @data buffer, one after the other without gaps\n+ * in between nor overlaps. Userspace shall populate the @data_size field with\n+ * the effective size, in bytes, of the @data buffer.\n+ *\n+ * Drivers shall take care of properly sizing of the extensible parameters\n+ * buffer @data array. The v4l2_params_buffer type is defined with a\n+ * flexible-array-member at the end, which resolves to a size of 0 bytes when\n+ * inspected with sizeof(struct v4l2_params_buffer). This of course is not\n+ * suitable for neither buffer allocation in the kernel driver nor for proper\n+ * handling in userspace of the @data buffer it has to populate.\n+ *\n+ * Drivers using this type in their userspace API definition are responsible\n+ * for providing the exact definition of the @data buffer size using the\n+ * v4l2_params_buffer_size() macro. The size shall be used\n+ * by the driver for buffers allocation and by userspace for populating the\n+ * @data buffer before queueing it to the driver\n+ *\n+ * Drivers that were already using extensible-parameters before the introduction\n+ * of this file define their own type-convertible implementation of this\n+ * type, see:\n+ * - Rockchip RkISP1: :c:type:`rkisp1_ext_params_cfg`\n+ * - Amlogic C3: :c:type:`c3_isp_params_cfg`\n+ *\n+ * @version: The parameters buffer version (platform-specific)\n+ * @data_size: The configuration data effective size, excluding this header\n+ * @data: The configuration data\n+ */\n+struct v4l2_params_buffer {\n+\t__u32 version;\n+\t__u32 data_size;\n+\t__u8 data[];\n+};\n+\n+#endif /* _V4L2_PARAMS_H_ */\n","prefixes":["1/4"]}