[PATCH v3 0/4] media: uvcvideo: Map known XU controls

[Ricardo Ribalda <ribalda@chromium.org>]

The UVC driver uses a custom ioctl `UVCIOC_CTRL_MAP` to map XU controls
into v4l2 controls. The most well know user of this feature is the
uvcdynctrl app.

This app has a set of XML files which contains the list of mappings.
Some of these mappings are standard and other ones are custom.

This series move the standard mappings to the kernel driver, so
userspace do not need to depend on external apps to use them.

While we are at it we realized that some of the mappings can be harmful
for the privacy of the user. This series introduce a mechanism to block
those mappings.

While we are at it, we complete the deprecation of the nodrop parameter.
Ideally, this patch should belong in a different series, but then we
will have conflicts... and who wants to works twice?

I have tried this series with a Logitech Webcam Pro 9000, that has been
donated by Hans de Goede (Thanks Hans!!!).

Without this patch and uvcdynctrl the device has 14 controls. (Ctrls A)

With this patch the device has 15 controls (Ctrls B):
Ctrls A
+
control 0x009a090a `Focus, Absolute' min 0 max 255 step 0 default 0 current 0

With uvcdynctrl and this patch the device has 17 controls (Ctrls C):
Ctrls B
+
control 0x0a046d71 `Disable video processing' min 0 max 1 step 1 default 0 current 0
control 0x0a046d72 `Raw bits per pixel' min 0 max 1 step 1 default 0 current 0

With uvcdynctrl and without this patch the device has 19 controls:
Ctrls C
+
control 0x0a046d05 `LED1 Mode' min 0 max 3 step 1 default 3 current 3
  0: Off
  1: On
  2: Blinking
  3: Auto (*)
control 0x0a046d06 `LED1 Frequency' min 0 max 255 step 1 default 0 current 0

BTW, Driver tested with virtme-ng. First time that I use it for uvc
development, and it works like a charm :).
virtme-run --kimg arch/x86/boot/bzImage --mods auto --show-command \
	--show-boot-console --verbose --qemu-opts -usb -device qemu-xhci \
	-device usb-host,hostbus=1,hostport=4

Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
---
Changes in v3:
- s/param/module parameter/ (Thanks HdG)
- Rebase to lastest media-committers/next and remove merged patches.
- Link to v2: https://lore.kernel.org/r/20251119-uvcdynctrl-v2-0-0359ffb98c9e@chromium.org

Changes in v2:
- Document how to get GUIDs
- Show clear deprecation intentions to the user.
- Add new patch for the Kconfig approach (Thanks Mauro).
- Remove duplicated control in commit message, provide background and
  add documentation. (Thanks Laurent)
- Block also uvc_query_ctrl for privacy controls (Thanks Gergo Koteles)
- Link to v1: https://lore.kernel.org/r/20251117-uvcdynctrl-v1-0-aed70eadf3d8@chromium.org

---
Ricardo Ribalda (4):
      media: uvcvideo: Import standard controls from uvcdynctrl
      media: uvcvideo: Announce deprecation intentions for UVCIOC_CTRL_MAP
      media: uvcvideo: Introduce allow_privacy_override module parameter
      media: uvcvideo: RFC: Convert allow_privacy_override into Kconfig

 .../userspace-api/media/drivers/uvcvideo.rst       |   2 +
 drivers/media/usb/uvc/Kconfig                      |  11 ++
 drivers/media/usb/uvc/uvc_ctrl.c                   | 212 +++++++++++++++++++++
 drivers/media/usb/uvc/uvc_v4l2.c                   |  11 ++
 drivers/media/usb/uvc/uvcvideo.h                   |   1 +
 include/linux/usb/uvc.h                            |  10 +
 6 files changed, 247 insertions(+)
---
base-commit: f6390408a846aacc2171c17d88b062e202d84e86
change-id: 20251117-uvcdynctrl-7b80f5bfbb41

Best regards,
-- 
Ricardo Ribalda <ribalda@chromium.org>