[PATCH RFC 0/3] Initial work for Rust abstraction for HID device driver development

Rahul Rameshbabu
2025-03-13T16:02:52Z

Hello,

I am a hobbyist developer who has been working on a project to create a new Rust
HID device driver and the needed core abstractions for writing more HID device
drivers in Rust. My goal is to support the USB Monitor Control Class needed for
functionality such as backlight control for monitors like the Apple Studio
Display and Apple Pro Display XDR. A new backlight API will be required to
support multiple backlight instances and will be mapped per DRM connector. The
current backlight API is designed around the assumption of only a single
internal panel being present. I am currently working on making this new API for
DRM in parallel to my work on the HID side of the stack for supporting these
displays.

https://binary-eater.github.io/tags/usb-monitor-control/

Julius Zint had attempted to do so a year ago with a C HID driver but was gated
by the lack of an appropriate backlight API for external displays. I asked him
for permission to do the work need in Rust and plan to accredit him for the HID
report handling for backlight in the USB Monitor Control Class standard.

https://lore.kernel.org/lkml/f95da7ff-06dd-2c0e-d563-7e5ad61c3bcc@redhat.com/

I was hoping to get initial feedback on this work to make sure I am on the right
path for making a Rust HID abstraction that would be acceptable upstream. The
patches compile with WERROR being disabled. This is necessary since Rust treats
missing documentation comments as warnings (which is a good thing). I also need
to go in and add more SAFETY comments.

Thanks,
Rahul Rameshbabu

Rahul Rameshbabu (3):
rust: core abstractions for HID drivers
rust: hid: USB Monitor Control Class driver
rust: hid: demo the core abstractions for probe and remove

drivers/hid/Kconfig | 16 ++
drivers/hid/Makefile | 1 +
drivers/hid/hid_monitor_control.rs | 42 +++++
rust/bindings/bindings_helper.h | 1 +
rust/kernel/hid.rs | 245 +++++++++++++++++++++++++++++
rust/kernel/lib.rs | 2 +
6 files changed, 307 insertions(+)
create mode 100644 drivers/hid/hid_monitor_control.rs
create mode 100644 rust/kernel/hid.rs

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2.47.2