From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from galahad.ideasonboard.com ([185.26.127.97]:42158 "EHLO galahad.ideasonboard.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S964892AbbHKODV (ORCPT ); Tue, 11 Aug 2015 10:03:21 -0400 From: Laurent Pinchart To: Hans Verkuil Cc: Junghak Sung , linux-media@vger.kernel.org, mchehab@osg.samsung.com, sakari.ailus@iki.fi, pawel@osciak.com, inki.dae@samsung.com, sw0312.kim@samsung.com, nenggun.kim@samsung.com, sangbae90.lee@samsung.com, rany.kwon@samsung.com Subject: Re: [RFC PATCH v2 4/5] media: videobuf2: Define vb2_buf_type and vb2_memory Date: Tue, 11 Aug 2015 17:04:14 +0300 Message-ID: <1984978.8NWP8Sj4WI@avalon> In-Reply-To: <55C9FFC7.8030308@xs4all.nl> References: <1438332277-6542-1-git-send-email-jh1009.sung@samsung.com> <30625903.5XtBkRR4hc@avalon> <55C9FFC7.8030308@xs4all.nl> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Sender: linux-media-owner@vger.kernel.org List-ID: Hi Hans, On Tuesday 11 August 2015 15:59:35 Hans Verkuil wrote: > On 08/11/15 15:56, Laurent Pinchart wrote: > > Hijacking this e-mail thread a bit, would it make sense for the new > > vb2-core to support different memory allocation for different planes ? > > I'm foreseeing use cases for buffers that bundle image data with > > meta-data, where image data should be captured to a dma-buf imported > > buffer, but meta-data doesn't need to be shared. In that case it wouldn't > > be easy for userspace to find a dma-buf provider for the meta-data > > buffers in order to import all planes. Being able to use dma-buf import > > for the image plane(s) and mmap for the meta-data plane would be easier. > > Yes, that would make sense, but I'd postpone that until someone actually > needs it. I might need it soon. Looks like my cunning plan to let someone else implement it failed ;-) > The biggest hurdle would be how to adapt the V4L2 API to this, and not the > actual vb2 core code. Changes will be needed in both, but I agree that in-kernel changes should be less of a hassle. -- Regards, Laurent Pinchart