Re: [RFC PATCH 0/2] rust: LED abstractions

[Lee Jones <lee@kernel.org>]

On Wed, 09 Oct 2024, Fiona Behrens wrote:

> This RFC implements a basic LED abstraction to show how this would work with rust.
> 
> Currently this just implements a sample driver, to show how to use the abstraction, which just
> prints the requested state, supporting a on/off LED and an led with brightness level up to 255 and
> hardware blinking. I intend to write a hardware specific driver for submitting.
> 
> The abstractions is a generic struct that holds a generic driver data on which the vtable is
> implemented. Because this struct also holds the c led_classdev (include/linux/leds.h) struct this
> struct is pinned and is using pin_init to create and directly register the LED.
> Dropping the struct unregisteres the LED. I plan to also add devm functions later, but as device
> abstractions in rust are not yet that far I opted agains that for the first iteration of the LED
> abstractions.
> 
> This is currently using core::time::Duration for the blinking interval, but will likely change that
> to use the Delta time type from FUJITA Tomonori [1].
> 
> This is requiring the Opaque::try_ffi_init patch by Alice Ryhl[2] which just got merged into
> char-misc-testing.
> 
> [1]: https://lore.kernel.org/rust-for-linux/20241005122531.20298-3-fujita.tomonori@gmail.com/
> [2]: https://lore.kernel.org/rust-for-linux/20240926-b4-miscdevice-v1-1-7349c2b2837a@google.com/
> 
> Fiona Behrens (2):
>   rust: LED abstraction
>   samples: rust: led sample
> 
>  rust/kernel/leds.rs      | 399 +++++++++++++++++++++++++++++++++++++++
>  rust/kernel/lib.rs       |   2 +
>  samples/rust/Kconfig     |  10 +
>  samples/rust/Makefile    |   1 +
>  samples/rust/rust_led.rs | 103 ++++++++++
>  5 files changed, 515 insertions(+)
>  create mode 100644 rust/kernel/leds.rs
>  create mode 100644 samples/rust/rust_led.rs

FYI: I'm not ignoring this patch-set.  On the contrary.  I'm trying to
place myself into a position where I can not only review it with some
confidence, but use it to author LED drivers.

-- 
Lee Jones [李琼斯]