From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mout.gmx.net ([212.227.15.19]:64982 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750990AbbECRph (ORCPT ); Sun, 3 May 2015 13:45:37 -0400 Date: Sun, 3 May 2015 19:45:32 +0200 (CEST) From: Guennadi Liakhovetski To: Hans Verkuil cc: Linux Media Mailing List Subject: Re: soc-camera: opinion poll - future directions In-Reply-To: <55465967.4060405@xs4all.nl> Message-ID: References: <55465967.4060405@xs4all.nl> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-media-owner@vger.kernel.org List-ID: Hi Hans, On Sun, 3 May 2015, Hans Verkuil wrote: > Hi Guennadi, > > On 05/03/2015 06:11 PM, Guennadi Liakhovetski wrote: > > Hi all, > > > > Just a quick opinion poll - where and how should the soc-camera framework > > and drivers be heading? Possible (probably not all) directions: > > > > (1) all is good, keep as is. That means keep all drivers, killing them off > > only when it becomes very obvious, that noone wants them, keep developing > > drivers, that are still being used and updating all of them on any API > > updates. Keep me as maintainer, which means slow patch processing rate and > > no active participation in new developments - at hardware, soc-camera or > > V4L levels. > > > > (2) we want more! I.e. some contributors are planning to either add new > > drivers to it or significantly develop existing ones, see significant > > benefit in it. In this case it might become necessary to replace me with > > someone, who can be more active in this area. > > > > (3) slowly phase out. Try to either deprecate and remove soc-camera > > drivers one by one or move them out to become independent V4L2 host or > > subdevice drivers, but keep updating while still there. > > > > (4) basically as (3) but even more aggressively - get rid of it ASAP:) > > > > Opinions? Expecially would be interesting to hear from respective > > host-driver maintainers / developers, sorry, not adding CCs, they probably > > read the list anyway:) > > I'm closest to 1. I would certainly not use it for new drivers, I see no > reason to do that anymore. The core frameworks are quite good these days > and I think the need for soc-camera has basically disappeared. But there > is no need to phase out or remove soc-camera drivers (unless they are > clearly broken and nobody will fix them). And if someone wants to turn > a soc-camera driver into a standalone driver, then I would encourage > that. Understand, thanks. > However, there are two things that need work fairly soon: > > 1) the dependency of subdev drivers on soc_camera: that has to go. I plan > to work on that, but the first step is to replace the video crop ops by > the pad selection ops. I finally got my Renesas sh7724 board up and running, Uhm... Does anyone really still care about V4L on SuperH?.. > so I hope to make progress on this soon. I'll update soc-camera as well > to conform to v4l2-compliance. Once that's done I will investigate how to > remove the soc-camera dependency. > > The soc-camera dependency kills the reusability of those drivers and it > really needs to be addressed. > > 2) Converting soc-camera videobuf drivers to vb2. At some point vb1 will be > removed, so any remaining vb1 driver will likely be killed off if nobody does > the conversion. I believe it is only omap1 and pxa that still use videobuf. > > I think omap1 might be a candidate for removal, but I don't know about the pxa. > Guennadi, what is the status of these drivers? Dont know, sorry. PXA in general seems to still be quite actively maintained - I recently saw a patch series for PXA CCF support, so, probably V4L is still in use too. > If I would do a vb2 conversion > for the pxa, would you be able to test it? I have a board with PXA270, and it still seems to be in the mainline, but I don't know how easy it would be to get it running with a current kernel. Thanks Guennadi