On Thu 11 October 2012 09:20:12 Hans Verkuil wrote: > On Thu October 11 2012 03:11:19 Mauro Carvalho Chehab wrote: > > Em Thu, 11 Oct 2012 09:22:34 +1000 > > Dave Airlie <airlied@xxxxxxxxx> escreveu: > > > > > On Thu, Oct 11, 2012 at 4:17 AM, Alan Cox <alan@xxxxxxxxxxxxxxxxxxx> wrote: > > > > On Wed, 10 Oct 2012 08:56:32 -0700 > > > > Robert Morell <rmorell@xxxxxxxxxx> wrote: > > > > > > > >> EXPORT_SYMBOL_GPL is intended to be used for "an internal implementation > > > >> issue, and not really an interface". The dma-buf infrastructure is > > > >> explicitly intended as an interface between modules/drivers, so it > > > >> should use EXPORT_SYMBOL instead. > > > > > > > > NAK. This needs at the very least the approval of all rights holders for > > > > the files concerned and all code exposed by this change. > > > > > > I think he has that. Maybe he just needs to list them. > > > > My understanding it that he doesn't, as the dmabuf interface exposes not only > > the code written by this driver's author, but other parts of the Kernel. > > > > Even if someone consider just the dmabuf driver, I participated and actively > > contributed, together with other open source developers, during the 3 days > > discussions that happened at Linaro's forum where most of dmabuf design was > > decided, and participated, reviewed, gave suggestions approved the code, etc > > via email. So, even not writing the dmabuf stuff myself, I consider myself as > > one of the intelectual authors of the solution. > > > > Also, as dmabuf will also expose media interfaces, > > That's new to me. All it does is represent a buffer. It doesn't expose any > interfaces, media or otherwise. > > > my understaning is > > that the drivers/media/ authors should also ack with this licensing > > (possible) change. I am one of the main contributors there. Alan also has > > copyrights there, and at other parts of the Linux Kernel, including the driver's > > core, from where all Linux Kernel drivers are derivative work, including this one. > > > > As Alan well said, many other core Linux Kernel authors very likely share > > this point of view. > > > > So, developers implicitly or explicitly copied in this thread that might be > > considering the usage of dmabuf on proprietary drivers should consider > > this email as a formal notification of my viewpoint: e. g. that I consider > > any attempt of using DMABUF or media core/drivers together with proprietary > > Kernelspace code as a possible GPL infringement. > > As long as dmabuf uses EXPORT_SYMBOL_GPL that is definitely correct. Does your > statement also hold if dmabuf would use EXPORT_SYMBOL? (Just asking) > > BTW, we should consider changing the control framework API to EXPORT_SYMBOL_GPL. > The number of contributors to v4l2-ctrls.c is very limited, and I have no > problem moving that to GPL. For me dmabuf is the rare exception where I prefer > EXPORT_SYMBOL to prevent the worse evil of forcing vendors to create incompatible > APIs. It's a sad but true that many GPU drivers are still closed source, > particularly in the embedded world for which dmabuf was primarily designed. One thing I am also worried about is that if vendors can't use dmabuf for their closed-source GPU driver, then they may not bother making GPL V4L drivers and instead stick to a proprietary solution (e.g. OpenMAX), Which would be a shame since we are making good progress with convincing vendors (esp. SoC vendors) to create GPL V4L2 drivers for their hardware. Regards, Hans -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
