From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id ED6D0CAC598 for ; Mon, 15 Sep 2025 17:19:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Cc:To:In-Reply-To:References :Message-Id:Content-Transfer-Encoding:Content-Type:MIME-Version:Subject:Date: From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=pUFmbTCcnlef7aCBW8VKyx17WQn5QvziJ3dxdWzNUYQ=; b=pUQNDxOJfyPM+sVU2kjbKuufvH hyQUnGzBm75P3zPdhJFNGsg7GoTJ9Jtv7TWhPN2vMkspgUJhXCUopqt+sawZbMK5U1QAj/e9RGUDu OxMIXDICwErBnj0ZBBkQwQ9UBju9wj4YolATKQtLNuSJZg4pmYNWVcQNTJlZ4NnErFsZ12O57Q6Pb Xunaq5enjc+FYYHXuVsdzE4neLdbNREgKjy/19TSV7rGgKG++FjiD/IBdInm0tLeLQ3hjKWI3D17Y IgcowDVYVLpi1dbHVrd5GDEqYz+BKyPqS9pz20VwY03gs3N+gnpRyj98vPtNS54RO8lFZOR8hLNXF z/ggzn4Q==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1uyCr0-00000005FpW-44mP; Mon, 15 Sep 2025 17:19:02 +0000 Received: from perceval.ideasonboard.com ([213.167.242.64]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1uyCqk-00000005FVC-30nA; Mon, 15 Sep 2025 17:18:48 +0000 Received: from [192.168.0.172] (mob-5-90-56-182.net.vodafone.it [5.90.56.182]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id EAF191189; Mon, 15 Sep 2025 19:17:26 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1757956647; bh=j9hWvCqelAGNvfHC+N6jQ1AbbIgP+Hu8HDlRfTcW5dU=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=MbD9+nQiI/UnoiPXoe7w1d82vS1VSty3VjlYeCKIP2pU11BimGoWAYfTbPQidJCPy 3jLhokZ4ZJluH5OBHsQl09t9HBED4jkrO7pRZSNF+TZs5Ck1qwCq2ZpUkyz4p0hYri 86DgX/gic9waEptrV5FrNjngBq9W6Gmfxgz8cy4s= From: Jacopo Mondi Date: Mon, 15 Sep 2025 19:18:17 +0200 Subject: [PATCH v5 8/8] media: Documentation: kapi: Add v4l2 generic ISP support MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20250915-extensible-parameters-validation-v5-8-e6db94468af3@ideasonboard.com> References: <20250915-extensible-parameters-validation-v5-0-e6db94468af3@ideasonboard.com> In-Reply-To: <20250915-extensible-parameters-validation-v5-0-e6db94468af3@ideasonboard.com> To: Dafna Hirschfeld , Laurent Pinchart , Keke Li , Mauro Carvalho Chehab , Heiko Stuebner , Dan Scally , Sakari Ailus , Antoine Bouyer Cc: linux-kernel@vger.kernel.org, linux-media@vger.kernel.org, linux-rockchip@lists.infradead.org, linux-arm-kernel@lists.infradead.org, Jacopo Mondi X-Mailer: b4 0.14.2 X-Developer-Signature: v=1; a=openpgp-sha256; l=3476; i=jacopo.mondi@ideasonboard.com; h=from:subject:message-id; bh=j9hWvCqelAGNvfHC+N6jQ1AbbIgP+Hu8HDlRfTcW5dU=; b=owEBbQKS/ZANAwAKAXI0Bo8WoVY8AcsmYgBoyEpqg+bIyroqcxI6unLoLO/6bMW1RVPjAUdT1 AClTMvpjHuJAjMEAAEKAB0WIQS1xD1IgJogio9YOMByNAaPFqFWPAUCaMhKagAKCRByNAaPFqFW PFEGD/9eZDpRaBL6tw+rDnhW4TmAaTMX788ap9B0/aPqgNRwhcNVtWLL08+dsEkW9pd5zEPEX8t E69I7kr3zHBN38fXyQFaNDatM2fHPh/G5tXVN1S1U1Xtp/3Aqg4NAR6I2VC/SlH5RJLjAz0htym dhC2VRjluLgVHIZe0Zwe3sj+5k5opgKzKTaUyEsCHEvhEyI0N4NssRtUbcXTXvvOQxTo1buOCVY WAntNNPSQPq6xX6etwjK5BYAI1L39EWAzzIQeYews1F+nN7oZ4umF9Ew5/Oi2dR7hSkYUHsyuEl ee4IiZRvd1lpUjli1EFqgn8yufg8uhPWvICWS5NrLyVYTEBRQ/aM1KqiGFTazHEAizANJd9XkBb b7jTZPgRdN7szXo3VJRqxUq8Ni5F4YCbFA95dBoc3ANsteuWrq0zeUzMTQLSz6LomNl3eGoRNGl t6dj5GyYMnLhBVNfNiGPPHfDcUf2wQjQZR9s2mTKCoNbih5jdeatxC6pYJP/2rMF72kiq+Ei5wt MIL9vZU2/Fd4G9ndWjtEIggnx3lOUZGO25UB3LG9KAt6bwImZpNrTCG9fTg9OZTzpVWr21+BfZf VwWabnY1f7yLtWFR1LTnJ+ngiHRrRl9c9fq+sc/VGiHCnvhjuRFiuQPZ9w/oSthh9ZqOwAbh6JQ 4PENvP4KH1yGaSA== X-Developer-Key: i=jacopo.mondi@ideasonboard.com; a=openpgp; fpr=72392EDC88144A65C701EA9BA5826A2587AD026B X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250915_101846_903923_F3613067 X-CRM114-Status: GOOD ( 14.94 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Add to the driver-api documentation the v4l2-isp.h types and helpers documentation. Reviewed-by: Daniel Scally Signed-off-by: Jacopo Mondi --- Documentation/driver-api/media/v4l2-core.rst | 1 + Documentation/driver-api/media/v4l2-isp.rst | 37 ++++++++++++++++++++++++++++ MAINTAINERS | 1 + 3 files changed, 39 insertions(+) diff --git a/Documentation/driver-api/media/v4l2-core.rst b/Documentation/driver-api/media/v4l2-core.rst index ad987c34ad2a8460bb95e97adc4d850d624e0b81..a5f5102c64cca57b57b54ab95882b26286fb27de 100644 --- a/Documentation/driver-api/media/v4l2-core.rst +++ b/Documentation/driver-api/media/v4l2-core.rst @@ -27,3 +27,4 @@ Video4Linux devices v4l2-common v4l2-tveeprom v4l2-jpeg + v4l2-isp diff --git a/Documentation/driver-api/media/v4l2-isp.rst b/Documentation/driver-api/media/v4l2-isp.rst new file mode 100644 index 0000000000000000000000000000000000000000..d778aa799347bfd0a95bd6887dd944ddad0fe4d1 --- /dev/null +++ b/Documentation/driver-api/media/v4l2-isp.rst @@ -0,0 +1,37 @@ +.. SPDX-License-Identifier: GPL-2.0 + +V4L2 generic ISP parameters and statistics support +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +ISP configuration parameters and statistics are processed and collected by +drivers and exchanged with userspace through data types that usually +reflect the ISP peripheral registers layout. + +Each ISP driver defines its own metadata format for parameters and statistics, +and exposing the registers layout in the format definition, part of the Linux +kernel uAPI/uABI interface, makes it really hard, if not impossible, to extend +the format in a backward compatible way to support new hardware blocks or +different revisions of the same peripheral IP. + +For these reasons Video4Linux2 defines generic types for ISP configuration +parameters and statistics with a set of associated helpers to support drivers +and users using generic types. + +Generic ISP configuration parameters +==================================== + +Drivers can use the generic and extensible configuration parameters format by +re-using the types defined in the include/uapi/linux/media/v4l2-isp.h uAPI +header file. + +The uAPI header defines generic types which the driver is expected to re-use and +provide definitions for the types of supported ISP blocks, their control +flags and the expected maximum size of a buffer of parameters. + +When a driver receives a buffer of parameters from userspace it shall validate +it by using the helper functions and types available in include/media/v4l2-isp.h +before accessing the buffer to apply the parameters to the hardware registers. + +Generic ISP support driver documentation +======================================== +.. kernel-doc:: include/media/v4l2-isp.h diff --git a/MAINTAINERS b/MAINTAINERS index 5e0e4208ebe6c58a9ea0834e1ebb36abd2de06e1..b0c5e6c2b21a5d5ebc63d2ae8b5c1b68fa912b33 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -26414,6 +26414,7 @@ V4L2 GENERIC ISP PARAMETERS AND STATISTIC FORMATS M: Jacopo Mondi L: linux-media@vger.kernel.org S: Maintained +F: Documentation/driver-api/media/v4l2-isp.rst F: Documentation/userspace-api/media/v4l/extensible-parameters.rst F: drivers/media/v4l2-core/v4l2-isp.c F: include/media/v4l2-isp.h -- 2.51.0