From patchwork Wed Sep 27 16:31:54 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sakari Ailus X-Patchwork-Id: 729563 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 10783E82CAE for ; Wed, 27 Sep 2023 16:32:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231717AbjI0Qcw (ORCPT ); Wed, 27 Sep 2023 12:32:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42082 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231730AbjI0Qcu (ORCPT ); Wed, 27 Sep 2023 12:32:50 -0400 Received: from mgamail.intel.com (mgamail.intel.com [192.55.52.115]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C177C91 for ; Wed, 27 Sep 2023 09:32:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1695832369; x=1727368369; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=NCBA2ZWrxrOSJHNzrnnv7zJUFHNyA34Wx+SZLYkoGpY=; b=UxiRSpeyo5Jdw9DdkDBTlRDHKwjubzJy9bMNVbfmvdsOeJO5Hy3LI+sx bCey9eJd2uV3p33RFy3joVJ7Wh+X58qKCn4vp7sAMRNRbFZLv4rUG0n15 W7fkt9KTiWVP3F7YONFlJNnqZPsRniD0ZJ/Tkm4QxS8B4rL5bi/X2R2Uv WS8xNzUloLha3ndV9LTAXiZPlZ3qZPzOO53qgV5qvh5d6ga0jkChi3vGy 5kCdUCts5WXoivbUTxYPEj2W+0DmW76+BKLFHJqQRnmvctRCkw9DZpEGJ oxiwe/f/gQT/JU4yIHUpsG7GS0t0z884iwXKIpvHeWcwX2EhWSMRf/IPR A==; X-IronPort-AV: E=McAfee;i="6600,9927,10846"; a="381771210" X-IronPort-AV: E=Sophos;i="6.03,181,1694761200"; d="scan'208";a="381771210" Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by fmsmga103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 27 Sep 2023 09:32:49 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10846"; a="892665746" X-IronPort-AV: E=Sophos;i="6.03,181,1694761200"; d="scan'208";a="892665746" Received: from turnipsi.fi.intel.com (HELO kekkonen.fi.intel.com) ([10.237.72.44]) by fmsmga001-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 27 Sep 2023 09:31:39 -0700 Received: from svinhufvud.ger.corp.intel.com (localhost [IPv6:::1]) by kekkonen.fi.intel.com (Postfix) with ESMTP id 3FE5A12035C; Wed, 27 Sep 2023 19:32:41 +0300 (EEST) 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" Subject: [PATCH v5 08/26] media: Documentation: Additional streams generally don't harm capture Date: Wed, 27 Sep 2023 19:31:54 +0300 Message-Id: <20230927163212.402025-9-sakari.ailus@linux.intel.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230927163212.402025-1-sakari.ailus@linux.intel.com> References: <20230927163212.402025-1-sakari.ailus@linux.intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org Having extra streams on the source end of the link that cannot be captured by the sink sub-device generally are not an issue, at least not on CSI-2 bus. Still document that there may be hardware specific limitations. For example on parallel bus this might not work on all cases. Signed-off-by: Sakari Ailus --- Documentation/userspace-api/media/v4l/dev-subdev.rst | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/Documentation/userspace-api/media/v4l/dev-subdev.rst b/Documentation/userspace-api/media/v4l/dev-subdev.rst index f375b820ab68..a387e8a15b8d 100644 --- a/Documentation/userspace-api/media/v4l/dev-subdev.rst +++ b/Documentation/userspace-api/media/v4l/dev-subdev.rst @@ -529,9 +529,9 @@ the its sink pad and allows to route them individually to one of its source pads. Subdevice drivers that support multiplexed streams are compatible with -non-multiplexed subdev drivers, but, of course, require a routing configuration -where the link between those two types of drivers contains only a single -stream. +non-multiplexed subdev drivers. However, if the driver at the sink end of a link +does not support streams, then only the stream 0 on source end may be +captured. There may be additional hardware specific limitations. Understanding streams ^^^^^^^^^^^^^^^^^^^^^