From patchwork Fri Apr 26 08:50:32 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sakari Ailus X-Patchwork-Id: 792814 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.20]) (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 C1DC613CAB7 for ; Fri, 26 Apr 2024 08:50:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.20 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1714121457; cv=none; b=N7I02dQHwSRgBvSAxhxro51Y5oVkdde/kM58e948UYAdjRSy/Q5WXMNdotkazEWnrXa2An7BYOcIjembJY73STz/3lWd6ZO5yf1mrlpArvCDRbw+c+5F6vRKHwVK8fNLLxubymX0wsATcxiBWv6EG5FTZ/fSTlqSV8P7wTcrJUE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1714121457; c=relaxed/simple; bh=9NVcs+CPjK/NLXHVLxYJeBlkgHJ6cOnfdXWiFvZE//s=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=K/wygHDQRe56Z4OiiMIiajmMjcoI4rZHMYlW9wLczFrt2RZZq36rhpOvMVkgpH0KxTsAQepXUuJ7wG6YHmfY8h2KsHGgmZ9PiOHJ3nK/M9IZSy8nOfYkzCQDFCOdoNJWt2HNzBZCw+i01PfgB7KjB6OCZmqZH18qu4rKPwxpOnc= 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=aDcB7yyp; arc=none smtp.client-ip=198.175.65.20 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="aDcB7yyp" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1714121456; x=1745657456; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=9NVcs+CPjK/NLXHVLxYJeBlkgHJ6cOnfdXWiFvZE//s=; b=aDcB7yypcIYgNWI7GMfXt+u5zIeEKByIm00+1KDXCcnTKGO3kE0w2eMR Y9vQBPDc3TIalr9iqbBkL0InV98zjgzLfAtT4zFg2LghNKyywqAuWXT2d oDO7yNftD/En5L5CvpdsiV6n/1v9uZDMZj/D3BCJySqdUnWDUzvCWtxpA At8rqk6haTReTjtu3wxGNAmTh/kqiYy2CkHg5Y8nlXoLAlnztmNzgL0ca uRVsUeaHuByqvfV+YDVPWdqgTwa7Ro/RD8XQFk6kir1uV5gHm/n/II0TM 9oFdVUgmusI1Y3FZbrKj7RNsJ/QBcsKxgwl7nX9eC1SRnY+0/BnTtJ6eO Q==; X-CSE-ConnectionGUID: v345xABRSn+93Yxt8pBX/A== X-CSE-MsgGUID: VIFxQWCxQGeMblTYR0f6/Q== X-IronPort-AV: E=McAfee;i="6600,9927,11055"; a="9683820" X-IronPort-AV: E=Sophos;i="6.07,232,1708416000"; d="scan'208";a="9683820" Received: from fmviesa002.fm.intel.com ([10.60.135.142]) by orvoesa112.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 26 Apr 2024 01:50:55 -0700 X-CSE-ConnectionGUID: RpPzXcHzS02F4xl6OH2X/Q== X-CSE-MsgGUID: /gJYeoZCQ8eg7NhbOgMK2w== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.07,232,1708416000"; d="scan'208";a="48598522" Received: from turnipsi.fi.intel.com (HELO kekkonen.fi.intel.com) ([10.237.72.44]) by fmviesa002-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 26 Apr 2024 01:50:52 -0700 Received: from svinhufvud.ger.corp.intel.com (localhost [IPv6:::1]) by kekkonen.fi.intel.com (Postfix) with ESMTP id 926191203ED; Fri, 26 Apr 2024 11:50:49 +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" , Alain Volmat Subject: [PATCH v3 08/14] media: Documentation: Additional streams generally don't harm capture Date: Fri, 26 Apr 2024 11:50:32 +0300 Message-Id: <20240426085038.943733-9-sakari.ailus@linux.intel.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20240426085038.943733-1-sakari.ailus@linux.intel.com> References: <20240426085038.943733-1-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 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 Reviewed-by: Tomi Valkeinen Reviewed-by: Laurent Pinchart --- 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..b76e02e54512 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 stream 0 of source end may be captured. +There may be additional limitations specific to the sink device. Understanding streams ^^^^^^^^^^^^^^^^^^^^^