From patchwork Wed Mar 13 07:24:46 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sakari Ailus X-Patchwork-Id: 13591074 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.8]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 78CAB168BA for ; Wed, 13 Mar 2024 07:25:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.8 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1710314755; cv=none; b=oawlAyjfRb3dkGhLjLR/WjHSinOs2Nkw7SShanTl7p0z0C2CNHoRzWJQVl79vwZoyDg/29vCyH+oHwbzgUsVWzQL/P5J0mWPOq40/mQN8ihMGxc4wDaNKrfMHTOtWRcE1FIYtYGbqZ4t/vVjkdnvJm2YdwpqNfBNHikdCDOID8U= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1710314755; c=relaxed/simple; bh=e5xHgCz203dWzQ6k/QXmaPwbpI3wWpeOsKmtVPvTpNs=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=ZatZc1has/C06azxKDvMV6mmnz6GDp+QrRVDGbP4x5jpnb3W4yB8gUqz+bwBaKziRZtT8zEtGjKnFlcRruxVmzUEa2WoVdVU1x1D1QH8ZNx0gBG5Syf/D9Chy8AmKZNhtkjBNHXOuy/iKfWMivrGIzJEkc4Opj0yR9RNoNFlAw4= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com; spf=none smtp.mailfrom=linux.intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=cgWvoWp+; arc=none smtp.client-ip=192.198.163.8 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="cgWvoWp+" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1710314753; x=1741850753; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=e5xHgCz203dWzQ6k/QXmaPwbpI3wWpeOsKmtVPvTpNs=; b=cgWvoWp+r/4OOHZ85MIKb/+8Q+5kLRXoG+/kctAOcumWGgXKQvPUF4ka 7uDHz0foCssYMxYhcTq376F/egQGKULiVfwqpi1AmzEu7NsXDSyxyYekn vunxwlweG6RjGKv5cna0ztKsT5CadoNq96z8BL8w2qvTMukhXn5aKwiFC Ra/fUiRf4jJhSkxEIFJ54sqAz+txrfNvA+2AFEeuIjO/ASvKPSKABL1Ch a3VSdIRO9XP5NmKfF+c0r8x90y9Hvd5n9LEaP0nHOgDTiDYcK/GMPXjkn pxq3aZ3CGpnhVoAXOr2OT+qa8uUqgmBsZA/wZgXm4TJ+Kk2yfrD776bgi g==; X-IronPort-AV: E=McAfee;i="6600,9927,11011"; a="22575556" X-IronPort-AV: E=Sophos;i="6.07,119,1708416000"; d="scan'208";a="22575556" Received: from fmviesa001.fm.intel.com ([10.60.135.141]) by fmvoesa102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Mar 2024 00:25:35 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.07,119,1708416000"; d="scan'208";a="42816370" Received: from turnipsi.fi.intel.com (HELO kekkonen.fi.intel.com) ([10.237.72.44]) by smtpauth.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Mar 2024 00:25:33 -0700 Received: from svinhufvud.ger.corp.intel.com (localhost [IPv6:::1]) by kekkonen.fi.intel.com (Postfix) with ESMTP id 2F0CE1203B3; Wed, 13 Mar 2024 09:25:30 +0200 (EET) From: Sakari Ailus To: linux-media@vger.kernel.org Cc: Laurent Pinchart , tomi.valkeinen@ideasonboard.com, bingbu.cao@intel.com, hongju.wang@intel.com, hverkuil@xs4all.nl, Andrey Konovalov , Jacopo Mondi , Dmitry Perchanov , "Ng, Khai Wen" , Alain Volmat Subject: [PATCH v8 08/38] media: Documentation: Document embedded data guidelines for camera sensors Date: Wed, 13 Mar 2024 09:24:46 +0200 Message-Id: <20240313072516.241106-9-sakari.ailus@linux.intel.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20240313072516.241106-1-sakari.ailus@linux.intel.com> References: <20240313072516.241106-1-sakari.ailus@linux.intel.com> Precedence: bulk X-Mailing-List: linux-media@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Document how embedded data support should be implemented for camera sensors, and when and how CCS embedded data format should be referenced. Signed-off-by: Sakari Ailus Reviewed-by: Julien Massot --- .../media/drivers/camera-sensor.rst | 29 +++++++++++++++++++ 1 file changed, 29 insertions(+) diff --git a/Documentation/userspace-api/media/drivers/camera-sensor.rst b/Documentation/userspace-api/media/drivers/camera-sensor.rst index 919a50e8b9d9..92545538b855 100644 --- a/Documentation/userspace-api/media/drivers/camera-sensor.rst +++ b/Documentation/userspace-api/media/drivers/camera-sensor.rst @@ -102,3 +102,32 @@ register programming sequences shall initialize the :ref:`V4L2_CID_HFLIP values programmed by the register sequences. The default values of these controls shall be 0 (disabled). Especially these controls shall not be inverted, independently of the sensor's mounting rotation. + +Embedded data +------------- + +Many sensors, mostly raw sensors, support embedded data which is used to convey +the sensor configuration for the captured frame back to the host. While CSI-2 is +the most common bus used by such sensors, embedded data can be available on +other bus types as well. + +Embedded data support shall use an internal source pad (a pad that has +``MEDIA_PAD_FL_SINK `` and ``MEDIA_PAD_FL_INTERNAL +`` flags set) and route to the external pad. If embedded +data output can be disabled in hardware, it should be possible to disable the +embedded data route via ``VIDIOC_SUBDEV_S_ROUTING`` IOCTL. + +In general, changing the embedded data format from the driver-configured values +is not supported. The height of the metadata is hardware specific and the width +is that (or less of that) of the image width, as configured on the pixel data +stream. + +CCS and non-CCS embedded data +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +Embedded data which is compliant with CCS definitions shall use ``CCS embedded +data format ``. Device specific embedded data which +is compliant up to MIPI CCS embedded data levels 1 or 2 only shall refer to CCS +embedded data formats and document the level of conformance. The rest of the +device specific embedded data format shall be documented in the context of the +data format itself.