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Date: Tue, 24 Feb 2026 17:42:33 +0100
Message-Id: <DGNCBY578GN2.2W7UIUULQ7U4N@kernel.org>
Subject: Re: [RFC PATCH v3 1/5] rtc: add device selector for rtc_class_ops
 callbacks
Cc: "Rafael J. Wysocki" <rafael@kernel.org>, "Alvin Sun"
 <alvin.sun@linux.dev>, "Miguel Ojeda" <ojeda@kernel.org>, "Boqun Feng"
 <boqun.feng@gmail.com>, "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>,
 <linux-rtc@vger.kernel.org>, <rust-for-linux@vger.kernel.org>, "Greg
 Kroah-Hartman" <gregkh@linuxfoundation.org>
To: "Alexandre Belloni" <alexandre.belloni@bootlin.com>
From: "Danilo Krummrich" <dakr@kernel.org>
References: <20260220225341c5eeb835@mail.local>
 <d1c9e33b-e1f3-41c6-af5e-a85fe2b86d10@linux.dev>
 <20260221111619162a41a1@mail.local>
 <CAJZ5v0jo2sLKWVOBJz7QP9x_aMZbaVx+ES7QwYWkTzHp7d2xLQ@mail.gmail.com>
 <DGKPPQI0QE73.S8I1M5NCI2BV@kernel.org> <20260222000556ea1938c0@mail.local>
 <DGLI4H9M0T6D.25RTLDVU5JRBE@kernel.org>
 <CAJZ5v0gtiQxBCknkaOzLKrDqUQfhKh_UjQkvgxJBL4UthbCOkg@mail.gmail.com>
 <DGLMGEZTM7E2.Y8VV9I6LI1P6@kernel.org>
 <DGMR9XOWP1V0.3C9219TYPXV6J@kernel.org> <2026022415010804e28202@mail.local>
 <DGNC6GEH8EV7.2WWAQ8DNCLRAB@kernel.org>
In-Reply-To: <DGNC6GEH8EV7.2WWAQ8DNCLRAB@kernel.org>

On Tue Feb 24, 2026 at 5:35 PM CET, Danilo Krummrich wrote:
> The reason we sometimes can is because, if you would need access to the
> irq::Registration from ioctls (e.g. for calling synchronize(), enable(),
> disable() etc.) it would be caught, because you couldn't access it withou=
t it
> being in rtc_data in the first place, and being forced to have it in rtc_=
data
> guarantees that the ordering can't be wrong.

I.e. as long as we can model a data dependency we can catch those things at
compile time.