[RFC PATCH 7/8] rust: add firmware abstractions

[FUJITA Tomonori]

On Mon, 27 May 2024 21:22:47 +0200
Danilo Krummrich <dakr at redhat.com> wrote:

>> > +/// Abstraction around a C firmware struct.
>> > +///
>> > +/// This is a simple abstraction around the C firmware API. Just like with the C API, firmware can
>> > +/// be requested. Once requested the abstraction provides direct access to the firmware buffer as
>> > +/// `&[u8]`. Alternatively, the firmware can be copied to a new buffer using `Firmware::copy`. The
>> > +/// firmware is released once [`Firmware`] is dropped.
>> > +///
>> > +/// # Examples
>> > +///
>> > +/// ```
>> > +/// let fw = Firmware::request("path/to/firmware.bin", dev.as_ref())?;
>> > +/// driver_load_firmware(fw.data());
>> > +/// ```
>> > +pub struct Firmware(Opaque<*const bindings::firmware>);
>> 
>> Wrapping a raw pointer is not the intended use of Qpaque type?
>> 
> 
> Indeed, will fix this in v2 and use NonNull instead. I'll also offload most of
> the boilerplate in the 'request' functions to some common 'request_internal' one.

You might need to add 'Invariants' comment on Firmware struct.

BTW, what merge window are you aiming for? As I wrote before, I have a
driver that needs the firmware abstractions (the minimum device
abstractions is enough; Device::as_raw() and as_ref()). So the sooner,
the better for me.