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To: Laurent Pinchart Cc: Leon Romanovsky , James Bottomley , Jiri Kosina , Dan Williams , ksummit@lists.linux.dev, linux-cxl@vger.kernel.org, linux-rdma@vger.kernel.org, netdev@vger.kernel.org, jgg@nvidia.com Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Hi Laurent On Thu, Jul 25, 2024 at 9:44=E2=80=AFPM Laurent Pinchart wrote: > > On Thu, Jul 25, 2024 at 04:20:35PM +0300, Leon Romanovsky wrote: > > On Thu, Jul 25, 2024 at 03:02:13PM +0200, Ricardo Ribalda Delgado wrote= : > > > On Thu, Jul 25, 2024 at 2:23=E2=80=AFPM Leon Romanovsky wrote: > > > > On Thu, Jul 25, 2024 at 11:26:38AM +0200, Ricardo Ribalda Delgado w= rote: > > > > > On Wed, Jul 24, 2024 at 10:02=E2=80=AFPM Laurent Pinchart wrote: > > > > > > > > <...> > > > > > > > > > It would be great to define what are the free software communitie= s > > > > > here. Distros and final users are also "free software communities= " and > > > > > they do not care about niche use cases covered by proprietary > > > > > software. > > > > > > > > Are you certain about that? > > > > > > As a user, and as an open source Distro developer I have a small hint= . > > > But you could also ask users what they think about not being able to > > > use their notebook's cameras. The last time that I could not use some > > > basic hardware from a notebook with Linux was 20 years ago. > > > > Lucky you, I still have consumer hardware (speaker) that doesn't work > > with Linux, and even now, there is basic hardware in my current > > laptop (HP docking station) that doesn't work reliably in Linux. > > > > > > > They only care (and should care) about normal workflows. > > > > > > > > What is a normal workflow? > > > > Does it mean that if user bought something very expensive he > > > > should not be able to use it with free software, because his > > > > usage is different from yours? > > > > > > > > Thanks > > > > > > It means that we should not block the standard usage for 99% of the > > > population just because 1% of the users cannot do something fancy wit= h > > > their device. > > > > Right, the problem is that in some areas the statistics slightly differ= ent. > > 99% population is blocked because 1% of the users don't need it and > > don't think that it is "normal" flow. > > > > > Let me give you an example. When I buy a camera I want to be able to > > > do Video Conferencing and take some static photos of documents. I do > > > not care about: automatic makeup, AI generated background, unicorn > > > filters, eyes recentering... But we need to give a way to vendors to > > > implement those things closely, without the marketing differentiators= , > > > vendors have zero incentive to invest in Linux, and that affects all > > > the population. > > I've seen these kind of examples being repeatedly given in discussions > related to camera ISP support in Linux. They are very misleading. These > are not the kind of features that are relevant for the device > pass-through discussion these day. Those are high-level use cases > implemented in userspace, and vendors can ship any closed-source > binaries they want there. What I care about is the features exposed by > the kernel to userspace API. The ISPs are gradually becoming programmable devices and they indeed help during all of those examples. Userspace needs to send/receive information from the ISP, and that is exactly what vendors want to keep in the close. Describing how they implement those algorithms is a patent minefield and their differentiating factor. > > > > This challenge seems to be solved for GPUs. I am using my AMD GPU > > > freely and my nephew can install the amdgpu-pro proprietary user spac= e > > > driver to play duke nukem (or whatever kids play now) at 2000 fps. > > > > > > There are other other subsystems that allow vendor passthrough and > > > their ecosystem has not collapsed. > > > > Yes, I completely agree with you on that. > > > > > Can we have some general guidance of what is acceptable? Can we defin= e > > > together the "normal workflow" and focus on a *full* open source > > > implementation of that? > > > > I don't think that is possible to define "normal workflow". Requirement > > to have open-source counterpart to everything exposed through UAPI is a > > valid one. I'm all for that. > > That's my current opinion as well, as least when it comes to the kernel > areas I mostly work with. > > -- > Regards, > > Laurent Pinchart --=20 Ricardo Ribalda