Greg KH recommends avoiding Alder Lake laptops – Intel’s webcam driver for Linux is long out

Greg Kroah-Hartman as the Linux kernel stability maintainer and actually Linus Torvalds deputy has suggested avoiding Intel Alder Lake laptops. While much of Alder Lake laptop support for Linux is in good shape, webcams are an exception. These newer laptops with the latest Intel webcam technology are currently not supported by the main kernel and require proprietary software to use. Some platforms like Ubuntu and ChromeOS are collecting these bubbles for the time being, while the actual open source solution will be upstream likely in a few months – or possibly a year.
The MIPI IPU6 camera found on newer Alder Lake laptops such as the Dell XPS 13 9315/9320 and Lenovo ThinkPad X1 Carbon is unfortunately not Linux-friendly at the moment.

Intel has released a repository with IPU6 kernel driver code, but is not intended for use with the kernel. Besides only working with a limited range of kernel versions (Linux 5.15 LTS is currently their target), the IPU6 driver code on GitHub is also not intended to be used with all OEM devices equipped with IPU6 webcams.

It was also argued that apart from the non-upstream kernel drivers, the use of IPU6 currently has a proprietary user-space stack, and the exposed user space API does not use the Video 4 Linux 2 (V4L2) common interface. The IPU6 camera is much more complex and therefore software side changes are more involved while camera manufacturers hesitate to open up any imaging algorithms. Libcamera developer Laurent Pinchart commented: “For now, I agree with your recommendation not to buy these devices if you want to support the camera.

Greg KH then commented:

I support this, do not buy these devices if the vendor does not want their drivers to be uploaded correctly.

A Google engineer then announced that there were plans to introduce the CAM kernel API for use by the IPU6 driver as an alternative to the existing V4L2 interfaces. The Chrome OS kernel sources have an initial CAM code, but it hasn’t gone through any review yet. Additionally, Google engineers want to convert legacy Intel image processing unit drivers to the CAM kernel API before sending them for review and attempting to keep it on the main system to make sure the API is suitable for legacy IPUs.

It is a long matter for the CAM API to act as a prerequisite for working on the Intel IPU6 driver upstream. It will probably take months for this engine API to be resolved “we are certainly not talking about “weeks”, we are talking about “months”. A few months is a realistic timeline.

This prompted Greg KH to confirm his earlier statement regarding not buying Alder Lake laptops:

Ok so combining this is a good year at best, realistically 2 years considering that once the first draft is submitted for review, the real work is going to start to happen.

So I will stick with my original statement, do not buy this hardware as it seems vendors do not want to add drivers any time soon 🙁

Laurent Pinchart then commented on the probability that it is a long process before new webcam driver support becomes available. “If I were to bet I would say no less than a year 🙂 And even then, as mentioned separately, you will have to convince the upstream community that the API is suitable. Ideally, work with the upstream today on a proposal that will satisfy all parties, and not wait for a year for full implementation to be ready, submitted and rejected.

In short, the newer Alder Lake laptops with MIPI IPU6 web cameras do not yet have support for upstream / open source Linux drivers. There are a few Intel kernel patches but they are not mainlined and currently require closed source user space software for this more sophisticated image processing unit. People like Ubuntu and Google Chrome OS deal with it by patching their builds with these bits. But if you need working webcam support on your laptop, it will likely be a better part of a year or more before some nice open-source Linux support for Intel IPU6 webcams comes out.

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