feat(users/flokli/ipu6-softisp): init

This code adds support for the ipu6 webcams via libcamera, based on the work in
https://copr.fedorainfracloud.org/coprs/jwrdegoede/ipu6-softisp/.

It's supposed to be included in your NixOS configuration imports.

Change-Id: Ifb71999ad61161fa23506b97cb449f73fb1270e3
Reviewed-on: https://cl.tvl.fyi/c/depot/+/10709
Tested-by: BuildkiteCI
Reviewed-by: flokli <flokli@flokli.de>
Autosubmit: flokli <flokli@flokli.de>

users/flokli/ipu6-softisp/README.md

@@ -0,0 +1,26 @@
+# ipu6-softisp
+
+This code adds support for the ipu6 webcams via libcamera, based on the work in
+https://copr.fedorainfracloud.org/coprs/jwrdegoede/ipu6-softisp/.
+
+It's supposed to be included in your NixOS configuration imports, and will:
+
+ - Add some patches to your kernel, which should apply on 6.7.x
+ - Add the `ipu6-camera-bins` firmware (still needed)
+ - Enable some kernel config options
+ - Add an udev rule so libcamera can do DMABUF things
+ - Override `services.pipewire.package` and
+   `services.pipewire.wireplumber.package` to use a pipewire built with a libcamera
+   with support for this webcam.
+
+Please make sure you don't have any of the `hardware.ipu6` options still
+enabled, as they use the closed-source userspace stack and will conflict.
+
+The testing instructions from
+https://copr.fedorainfracloud.org/coprs/jwrdegoede/ipu6-softisp/ still apply.
+
+`qcam` can be found in `libcamera-qcam` (pending on
+https://github.com/NixOS/nixpkgs/pull/284964 to trickle into master).
+
+Thanks to Hans de Goede for helping me bringing this up, as well as to
+puckipedia for sorting out some pipewire-related confusion.