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2026-01-26Merge tag 'v6.19-rc7' into driver-core-nextDanilo Krummrich
We need the driver-core fixes in here as well to build on top of. Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2026-01-16rust: driver: drop device private data post unbindDanilo Krummrich
Currently, the driver's device private data is allocated and initialized from driver core code called from bus abstractions after the driver's probe() callback returned the corresponding initializer. Similarly, the driver's device private data is dropped within the remove() callback of bus abstractions after calling the remove() callback of the corresponding driver. However, commit 6f61a2637abe ("rust: device: introduce Device::drvdata()") introduced an accessor for the driver's device private data for a Device<Bound>, i.e. a device that is currently bound to a driver. Obviously, this is in conflict with dropping the driver's device private data in remove(), since a device can not be considered to be fully unbound after remove() has finished: We also have to consider registrations guarded by devres - such as IRQ or class device registrations - which are torn down after remove() in devres_release_all(). Thus, it can happen that, for instance, a class device or IRQ callback still calls Device::drvdata(), which then runs concurrently to remove() (which sets dev->driver_data to NULL and drops the driver's device private data), before devres_release_all() started to tear down the corresponding registration. This is because devres guarded registrations can, as expected, access the corresponding Device<Bound> that defines their scope. In C it simply is the driver's responsibility to ensure that its device private data is freed after e.g. an IRQ registration is unregistered. Typically, C drivers achieve this by allocating their device private data with e.g. devm_kzalloc() before doing anything else, i.e. before e.g. registering an IRQ with devm_request_threaded_irq(), relying on the reverse order cleanup of devres. Technically, we could do something similar in Rust. However, the resulting code would be pretty messy: In Rust we have to differentiate between allocated but uninitialized memory and initialized memory in the type system. Thus, we would need to somehow keep track of whether the driver's device private data object has been initialized (i.e. probe() was successful and returned a valid initializer for this memory) and conditionally call the destructor of the corresponding object when it is freed. This is because we'd need to allocate and register the memory of the driver's device private data *before* it is initialized by the initializer returned by the driver's probe() callback, because the driver could already register devres guarded registrations within probe() outside of the driver's device private data initializer. Luckily there is a much simpler solution: Instead of dropping the driver's device private data at the end of remove(), we just drop it after the device has been fully unbound, i.e. after all devres callbacks have been processed. For this, we introduce a new post_unbind() callback private to the driver-core, i.e. the callback is neither exposed to drivers, nor to bus abstractions. This way, the driver-core code can simply continue to conditionally allocate the memory for the driver's device private data when the driver's initializer is returned from probe() - no change needed - and drop it when the driver-core code receives the post_unbind() callback. Closes: https://lore.kernel.org/all/DEZMS6Y4A7XE.XE7EUBT5SJFJ@kernel.org/ Fixes: 6f61a2637abe ("rust: device: introduce Device::drvdata()") Acked-by: Alice Ryhl <aliceryhl@google.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Igor Korotin <igor.korotin.linux@gmail.com> Link: https://patch.msgid.link/20260107103511.570525-7-dakr@kernel.org [ Remove #ifdef CONFIG_RUST, rename post_unbind() to post_unbind_rust(). - Danilo] Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2026-01-16rust: driver: add DriverData type to the DriverLayout traitDanilo Krummrich
Add an associated type DriverData to the DriverLayout trait indicating the type of the driver's device private data. Acked-by: Alice Ryhl <aliceryhl@google.com> Acked-by: Igor Korotin <igor.korotin.linux@gmail.com> Link: https://patch.msgid.link/20260107103511.570525-6-dakr@kernel.org Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2026-01-16rust: driver: add DEVICE_DRIVER_OFFSET to the DriverLayout traitDanilo Krummrich
Add an associated const DEVICE_DRIVER_OFFSET to the DriverLayout trait indicating the offset of the embedded struct device_driver within Self::DriverType, i.e. the specific driver structs, such as struct pci_driver or struct platform_driver. Acked-by: Alice Ryhl <aliceryhl@google.com> Acked-by: Igor Korotin <igor.korotin.linux@gmail.com> Link: https://patch.msgid.link/20260107103511.570525-5-dakr@kernel.org Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2026-01-16rust: driver: introduce a DriverLayout traitDanilo Krummrich
The DriverLayout trait describes the layout of a specific driver structure, such as `struct pci_driver` or `struct platform_driver`. In a first step, this replaces the associated type RegType of the RegistrationOps with the DriverLayout::DriverType associated type. Acked-by: Alice Ryhl <aliceryhl@google.com> Acked-by: Igor Korotin <igor.korotin.linux@gmail.com> Link: https://patch.msgid.link/20260107103511.570525-4-dakr@kernel.org [ Rename driver::Driver to driver::DriverLayout, as it represents the layout of a driver structure rather than the driver structure itself. - Danilo ] Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2026-01-12Merge tag 'v6.19-rc5' into driver-core-nextDanilo Krummrich
We need the driver-core fixes in here as well to build on top of. Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2026-01-07rust: driver-core: use "kernel vertical" style for importsDanilo Krummrich
Convert all imports to use "kernel vertical" style. With this, subsequent patches neither introduce unrelated changes nor leave an inconsistent import pattern. While at it, drop unnecessary imports covered by prelude::*. Link: https://docs.kernel.org/rust/coding-guidelines.html#imports Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: https://patch.msgid.link/20260105142123.95030-3-dakr@kernel.org Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-12-30rust: driver: fix broken intra-doc links to example driver typesAlice Ryhl
The `auxiliary` and `pci` modules are conditional on `CONFIG_AUXILIARY_BUS` and `CONFIG_PCI` respectively. When these are disabled, the intra-doc links to `auxiliary::Driver` and `pci::Driver` break, causing rustdoc warnings (or errors with `-D warnings`). error: unresolved link to `kernel::auxiliary::Driver` --> rust/kernel/driver.rs:82:28 | 82 | //! [`auxiliary::Driver`]: kernel::auxiliary::Driver | ^^^^^^^^^^^^^^^^^^^^^^^^^ no item named `auxiliary` in module `kernel` Fix this by making the documentation for these examples conditional on the corresponding configuration options. Fixes: 970a7c68788e ("driver: rust: expand documentation for driver infrastructure") Signed-off-by: Alice Ryhl <aliceryhl@google.com> Reported-by: FUJITA Tomonori <fujita.tomonori@gmail.com> Closes: https://lore.kernel.org/rust-for-linux/20251209.151817.744108529426448097.fujita.tomonori@gmail.com/ Link: https://patch.msgid.link/20251227-driver-types-v1-1-1916154fbe5e@google.com Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-10-21rust: driver: let probe() return impl PinInit<Self, Error>Danilo Krummrich
The driver model defines the lifetime of the private data stored in (and owned by) a bus device to be valid from when the driver is bound to a device (i.e. from successful probe()) until the driver is unbound from the device. This is already taken care of by the Rust implementation of the driver model. However, we still ask drivers to return a Result<Pin<KBox<Self>>> from probe(). Unlike in C, where we do not have the concept of initializers, but rather deal with uninitialized memory, drivers can just return an impl PinInit<Self, Error> instead. This contributes to more clarity to the fact that a driver returns it's device private data in probe() and the Rust driver model owns the data, manages the lifetime and - considering the lifetime - provides (safe) accessors for the driver. Hence, let probe() functions return an impl PinInit<Self, Error> instead of Result<Pin<KBox<Self>>>. Reviewed-by: Alice Ryhl <aliceryhl@google.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Reviewed-by: Alexandre Courbot <acourbot@nvidia.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-08-12driver: rust: expand documentation for driver infrastructureDanilo Krummrich
Add documentation about generic driver infrastructure, representing a guideline on how the generic driver infrastructure is intended to be used to implement bus specific driver APIs. This covers aspects such as the bus specific driver trait, adapter implementation, driver registration and custom device ID types. Reviewed-by: Daniel Almeida <daniel.almeida@collabora.com> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Alexandre Courbot <acourbot@nvidia.com> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Link: https://lore.kernel.org/r/20250722150110.23565-4-dakr@kernel.org Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-07-16rust: device_id: split out index support into a separate traitFUJITA Tomonori
Introduce a new trait `RawDeviceIdIndex`, which extends `RawDeviceId` to provide support for device ID types that include an index or context field (e.g., `driver_data`). This separates the concerns of layout compatibility and index-based data embedding, and allows `RawDeviceId` to be implemented for types that do not contain a `driver_data` field. Several such structures are defined in include/linux/mod_devicetable.h. Refactor `IdArray::new()` into a generic `build()` function, which takes an optional offset. Based on the presence of `RawDeviceIdIndex`, index writing is conditionally enabled. A new `new_without_index()` constructor is also provided for use cases where no index should be written. This refactoring is a preparation for enabling the PHY abstractions to use the RawDeviceId trait. The changes to acpi.rs and driver.rs were made by Danilo. Reviewed-by: Trevor Gross <tmgross@umich.edu> Signed-off-by: FUJITA Tomonori <fujita.tomonori@gmail.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: https://lore.kernel.org/r/20250711040947.1252162-2-fujita.tomonori@gmail.com Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-07-01rust: fix typo in #[repr(transparent)] commentsFUJITA Tomonori
Fix a typo in several comments where `#[repr(transparent)]` was mistakenly written as `#[repr(transparent)` (missing closing bracket). Signed-off-by: FUJITA Tomonori <fujita.tomonori@gmail.com> Link: https://lore.kernel.org/r/20250623225846.169805-1-fujita.tomonori@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-06-26rust: driver: Add ACPI id table support to Adapter traitIgor Korotin
Extend the `Adapter` trait to support ACPI device identification. This mirrors the existing Open Firmware (OF) support (`of_id_table`) and enables Rust drivers to match and retrieve ACPI-specific device data when `CONFIG_ACPI` is enabled. To avoid breaking compilation, a stub implementation of `acpi_id_table()` is added to the Platform adapter; the full implementation will be provided in a subsequent patch. Signed-off-by: Igor Korotin <igor.korotin.linux@gmail.com> Link: https://lore.kernel.org/r/20250620153914.295679-1-igor.korotin.linux@gmail.com [ Fix clippy warning if #[cfg(not(CONFIG_OF))]; fix checkpatch.pl line length warnings. - Danilo ] Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-06-26rust: driver: Consolidate `Adapter::of_id_info` methods using `#[cfg]`Igor Korotin
Refactor the `of_id_info` methods in the `Adapter` trait to reduce duplication. Previously, the method had two versions selected via `#[cfg(...)]` and `#[cfg(not(...))]`. This change merges them into a single method by using `#[cfg]` blocks within the method body. Suggested-by: Benno Lossin <lossin@kernel.org> Signed-off-by: Igor Korotin <igor.korotin.linux@gmail.com> Link: https://lore.kernel.org/r/20250620153656.294468-1-igor.korotin.linux@gmail.com [ Fix clippy warning if #[cfg(not(CONFIG_OF))]; fix checkpatch.pl line length warnings. - Danilo ] Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-03-16rust: make pin-init its own crateBenno Lossin
Rename relative paths inside of the crate to still refer to the same items, also rename paths inside of the kernel crate and adjust the build system to build the crate. [ Remove the `expect` (and thus the `lint_reasons` feature) since the tree now uses `quote!` from `rust/macros/export.rs`. Remove the `TokenStream` import removal, since it is now used as well. In addition, temporarily (i.e. just for this commit) use an `--extern force:alloc` to prevent an unknown `new_uninit` error in the `rustdoc` target. For context, please see a similar case in: https://lore.kernel.org/lkml/20240422090644.525520-1-ojeda@kernel.org/ And adjusted the message above. - Miguel ] Signed-off-by: Benno Lossin <benno.lossin@proton.me> Reviewed-by: Fiona Behrens <me@kloenk.dev> Tested-by: Andreas Hindborg <a.hindborg@kernel.org> Link: https://lore.kernel.org/r/20250308110339.2997091-16-benno.lossin@proton.me Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-01-07rust: driver: address soundness issue in `RegistrationOps`Danilo Krummrich
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>
2024-12-20rust: driver: implement `Adapter`Danilo Krummrich
In order to not duplicate code in bus specific implementations (e.g. platform), implement a generic `driver::Adapter` to represent the connection of matched drivers and devices. Bus specific `Adapter` implementations can simply implement this trait to inherit generic functionality, such as matching OF or ACPI device IDs and ID table entries. Suggested-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/20241219170425.12036-14-dakr@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-20rust: implement generic driver registrationDanilo Krummrich
Implement the generic `Registration` type and the `RegistrationOps` trait. The `Registration` structure is the common type that represents a driver registration and is typically bound to the lifetime of a module. However, it doesn't implement actual calls to the kernel's driver core to register drivers itself. Instead the `RegistrationOps` trait is provided to subsystems, which have to implement `RegistrationOps::register` and `RegistrationOps::unregister`. Subsystems have to provide an implementation for both of those methods where the subsystem specific variants to register / unregister a driver have to implemented. For instance, the PCI subsystem would call __pci_register_driver() from `RegistrationOps::register` and pci_unregister_driver() from `DrvierOps::unregister`. Co-developed-by: Wedson Almeida Filho <wedsonaf@gmail.com> Signed-off-by: Wedson Almeida Filho <wedsonaf@gmail.com> Signed-off-by: Danilo Krummrich <dakr@kernel.org> Tested-by: Dirk Behme <dirk.behme@de.bosch.com> Tested-by: Fabien Parent <fabien.parent@linaro.org> Link: https://lore.kernel.org/r/20241219170425.12036-3-dakr@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>