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Date: Mon, 06 Jul 2026 12:40:53 +0200
Message-Id: <DJRFAY0H6KXP.HN16JEY756AC@kernel.org>
Subject: Re: [RFC PATCH v2 10/11] rust: usb: keep usb::Device private and
 gate transfers on Interface<Bound>
Cc: <rust-for-linux@vger.kernel.org>, <linux-usb@vger.kernel.org>, "Greg
 Kroah-Hartman" <gregkh@linuxfoundation.org>, "Daniel Almeida"
 <daniel.almeida@collabora.com>, "Miguel Ojeda" <ojeda@kernel.org>, "Boqun
 Feng" <boqun@kernel.org>, "Gary Guo" <gary@garyguo.net>,
 =?utf-8?q?Bj=C3=B6rn_Roy_Baron?= <bjorn3_gh@protonmail.com>, "Benno Lossin"
 <lossin@kernel.org>, "Andreas Hindborg" <a.hindborg@kernel.org>, "Alice
 Ryhl" <aliceryhl@google.com>, "Trevor Gross" <tmgross@umich.edu>,
 "Alexandre Courbot" <acourbot@nvidia.com>, <linux-kernel@vger.kernel.org>
To: "Mike Lothian" <mike@fireburn.co.uk>
From: "Danilo Krummrich" <dakr@kernel.org>
References: <20260617145946.1894-1-mike@fireburn.co.uk>
 <20260703030020.2694-1-mike@fireburn.co.uk>
 <20260703030020.2694-11-mike@fireburn.co.uk>
In-Reply-To: <20260703030020.2694-11-mike@fireburn.co.uk>

On Fri Jul 3, 2026 at 5:00 AM CEST, Mike Lothian wrote:
>  - Add `Interface::as_bound()` for drivers that keep a refcounted
>    `ARef<Interface>` and perform transfers from a deferred context (a wor=
k
>    item), with a safety contract requiring the work be flushed before unb=
ind.

There's no need for this, drivers should have a bound device (or interface =
in
this case) where it is needed.

If you hit the case where you need an unsafe as_bound() method, it means th=
at
either your design has issues or the corresponding infrastructure that cons=
iders
it isn't available yet.