From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [213.167.242.64]) (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 E51CA304BDF for ; Wed, 18 Feb 2026 22:22:16 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=213.167.242.64 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771453338; cv=none; b=AmBcTLZISNMXJTUM93gs+y8ZTXb0PjDY1YSBaQGsY08RusVt23+gOWp92hgSE3JbCsnh7DWLFPuw7YRS/NwA18uNBnGQGb06vtMksQ8XSK3QBhqw/7q3EK3WapnPTjX+j+HopSPqOxDwPOFVj0uQVTOcMU85l4q0KyBZy+whm8o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771453338; c=relaxed/simple; bh=c2bYFjKYrsZTZG+WRbXqjELmtLaVjNQ57pajq83q4RQ=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=TNVm1Htapxtr1Y4hgl5EC4Vx1O8ur4lXYnC/K7Xl8YO0eO8FLPR5yeFCjh8sO4P5fRhvFs42VS9LKvgp6NKSqYNOKWnzVNYBt7hf7sBgcsLMtVHXsbHjIEpsMwnwClnsauCiWF/V0i5OPG4jbtkX32CIx+VdEWhugtkQVDbYpUc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=ideasonboard.com; spf=pass smtp.mailfrom=ideasonboard.com; dkim=pass (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b=NCgqywQY; arc=none smtp.client-ip=213.167.242.64 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=ideasonboard.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=ideasonboard.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b="NCgqywQY" Received: from killaraus.ideasonboard.com (unknown [83.245.237.175]) by perceval.ideasonboard.com (Postfix) with UTF8SMTPSA id 7D2C066B; Wed, 18 Feb 2026 23:21:22 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1771453282; bh=c2bYFjKYrsZTZG+WRbXqjELmtLaVjNQ57pajq83q4RQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=NCgqywQYet4KeDXgFhOMhOw7yUM5r3pYvFMnSqHLZhZSRowHUlpcXQrNjOLgVpPrX hcpBDj6mD9Dc002M1vbivLBCEivjZkq74Ewk0eP5aqL0troPrzDSeowgmqcbF0ZLme 6dx6Ss94L0TFAkAhzp8kw7zhP7sNEhcpHE/y4Z9M= Date: Wed, 18 Feb 2026 23:22:11 +0100 From: Laurent Pinchart To: Itay Perl Cc: Ricardo Ribalda , Hans de Goede , "linux-media@vger.kernel.org" , Itay Chamiel Subject: Re: uvcvideo regression: loss of access to full UVC payload header for generic UVC devices since 6.17 Message-ID: <20260218222211.GE57525@killaraus.ideasonboard.com> References: Precedence: bulk X-Mailing-List: linux-media@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: On Wed, Feb 18, 2026 at 11:56:28AM +0000, Itay Perl wrote: > On 18 February 2026 19:17, Ricardo Ribalda wrote: > > On Wed, 18 Feb 2026 at 11:59, Itay Perl wrote: > > > Would restoring the previous behavior be acceptable for compatibility? > > > Alternatively (or additionally), would it make sense to introduce a dedicated > > > metadata format that allows userspace to request the full UVC header for > > > generic devices? > > > > By any chance the device that you are using supports > > V4L2_META_FMT_UVC_MSXU_1_5 ? > > If the device exposes the UVC_MSXU_CONTROL_METADATA control, that > > format should be available, and it provices access to all the UVC > > header as you had before. > > > > Alternatively, if this is needed for a specific device you could send > > a patch adding the UVC_QUIRK_MSXU_META for that device. > > Would that work for you? > > My device is an internal development platform and does not have a public VID/PID > that could reasonably be added to the driver. > > I may be able to implement the MSXU control on the device side as a workaround, > but I'm concerned that this could cause issues when the device is used on a > Windows machine, which may expect the UVC header to follow a certain > format when MSXU is present. Does your device implement a vendor-specific metadata format ? -- Regards, Laurent Pinchart