`of::DeviceId` is an abstraction around `struct of_device_id`. This is used by subsequent patches, in particular the platform bus abstractions, to create OF device ID tables. Signed-off-by: Danilo Krummrich <dakr@xxxxxxxxxx> --- MAINTAINERS | 1 + rust/bindings/bindings_helper.h | 1 + rust/kernel/lib.rs | 1 + rust/kernel/of.rs | 63 +++++++++++++++++++++++++++++++++ 4 files changed, 66 insertions(+) create mode 100644 rust/kernel/of.rs diff --git a/MAINTAINERS b/MAINTAINERS index d9c512a3e72b..87eb9a7869eb 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -17340,6 +17340,7 @@ T: git git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux.git F: Documentation/ABI/testing/sysfs-firmware-ofw F: drivers/of/ F: include/linux/of*.h +F: rust/kernel/of.rs F: scripts/dtc/ F: tools/testing/selftests/dt/ K: of_overlay_notifier_ diff --git a/rust/bindings/bindings_helper.h b/rust/bindings/bindings_helper.h index cd4edd6496ae..312f03cbdce9 100644 --- a/rust/bindings/bindings_helper.h +++ b/rust/bindings/bindings_helper.h @@ -15,6 +15,7 @@ #include <linux/firmware.h> #include <linux/jiffies.h> #include <linux/mdio.h> +#include <linux/of_device.h> #include <linux/pci.h> #include <linux/phy.h> #include <linux/refcount.h> diff --git a/rust/kernel/lib.rs b/rust/kernel/lib.rs index 3ec690eb6d43..5946f59f1688 100644 --- a/rust/kernel/lib.rs +++ b/rust/kernel/lib.rs @@ -51,6 +51,7 @@ pub mod list; #[cfg(CONFIG_NET)] pub mod net; +pub mod of; pub mod page; pub mod prelude; pub mod print; diff --git a/rust/kernel/of.rs b/rust/kernel/of.rs new file mode 100644 index 000000000000..a37629997974 --- /dev/null +++ b/rust/kernel/of.rs @@ -0,0 +1,63 @@ +// SPDX-License-Identifier: GPL-2.0 + +//! Open Firmware abstractions. +//! +//! C header: [`include/linux/of_*.h`](srctree/include/linux/of_*.h) + +use crate::{bindings, device_id::RawDeviceId, prelude::*}; + +/// An open firmware device id. +#[derive(Clone, Copy)] +pub struct DeviceId(bindings::of_device_id); + +// SAFETY: +// * `DeviceId` is a `#[repr(transparent)` wrapper of `struct of_device_id` and does not add +// additional invariants, so it's safe to transmute to `RawType`. +// * `DRIVER_DATA_OFFSET` is the offset to the `data` field. +unsafe impl RawDeviceId for DeviceId { + type RawType = bindings::of_device_id; + + const DRIVER_DATA_OFFSET: usize = core::mem::offset_of!(bindings::of_device_id, data); + + fn index(&self) -> usize { + self.0.data as _ + } +} + +impl DeviceId { + /// Create a new device id from an OF 'compatible' string. + pub const fn new(compatible: &'static CStr) -> Self { + let src = compatible.as_bytes_with_nul(); + // Replace with `bindings::of_device_id::default()` once stabilized for `const`. + // SAFETY: FFI type is valid to be zero-initialized. + let mut of: bindings::of_device_id = unsafe { core::mem::zeroed() }; + + let mut i = 0; + while i < src.len() { + of.compatible[i] = src[i] as _; + i += 1; + } + + Self(of) + } + + /// The compatible string of the embedded `struct bindings::of_device_id` as `&CStr`. + pub fn compatible<'a>(&self) -> &'a CStr { + // SAFETY: `self.compatible` is a valid `char` pointer. + unsafe { CStr::from_char_ptr(self.0.compatible.as_ptr()) } + } +} + +/// Create an OF `IdTable` with an "alias" for modpost. +#[macro_export] +macro_rules! of_device_table { + ($table_name:ident, $module_table_name:ident, $id_info_type: ty, $table_data: expr) => { + const $table_name: $crate::device_id::IdArray< + $crate::of::DeviceId, + $id_info_type, + { $table_data.len() }, + > = $crate::device_id::IdArray::new($table_data); + + $crate::module_device_table!("of", $module_table_name, $table_name); + }; +} -- 2.46.2