As by now, platform::Device is implemented as:
#[derive(Clone)]
pub struct Device(ARef<device::Device>);
This may be convenient, but has the implication that drivers can call
device methods that require a mutable reference concurrently at any
point of time.
Instead define platform::Device as
pub struct Device<Ctx: DeviceContext = Normal>(
Opaque<bindings::platform_dev>,
PhantomData<Ctx>,
);
and manually implement the AlwaysRefCounted trait.
With this we can implement methods that should only be called from
bus callbacks (such as probe()) for platform::Device<Core>. Consequently,
we make this type accessible in bus callbacks only.
Arbitrary references taken by the driver are still of type
ARef<platform::Device> and hence don't provide access to methods that are
reserved for bus callbacks.
Fixes: 683a63befc ("rust: platform: add basic platform device / driver abstractions")
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Acked-by: Boqun Feng <boqun.feng@gmail.com>
Link: https://lore.kernel.org/r/20250314160932.100165-5-dakr@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The `RegistrationOps` trait holds some obligations to the caller and
implementers. While being documented, the trait and the corresponding
functions haven't been marked as unsafe.
Hence, markt the trait and functions unsafe and add the corresponding
safety comments.
This patch does not include any fuctional changes.
Reported-by: Gary Guo <gary@garyguo.net>
Closes: https://lore.kernel.org/rust-for-linux/20241224195821.3b43302b.gary@garyguo.net/
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Reviewed-by: Gary Guo <gary@garyguo.net>
Link: https://lore.kernel.org/r/20250103164655.96590-4-dakr@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Implement the basic platform bus abstractions required to write a basic
platform driver. This includes the following data structures:
The `platform::Driver` trait represents the interface to the driver and
provides `platform::Driver::probe` for the driver to implement.
The `platform::Device` abstraction represents a `struct platform_device`.
In order to provide the platform bus specific parts to a generic
`driver::Registration` the `driver::RegistrationOps` trait is implemented
by `platform::Adapter`.
Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Tested-by: Dirk Behme <dirk.behme@de.bosch.com>
Link: https://lore.kernel.org/r/20241219170425.12036-15-dakr@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
