`acpi::DeviceId` is an abstraction around `struct acpi_device_id`.
This is used by subsequent patches, in particular the i2c driver
abstractions, to create ACPI device ID tables.
Signed-off-by: Igor Korotin <igor.korotin.linux@xxxxxxxxx>
---
MAINTAINERS | 1 +
rust/kernel/acpi.rs | 60 +++++++++++++++++++++++++++++++++++++++++++++
rust/kernel/lib.rs | 1 +
3 files changed, 62 insertions(+)
create mode 100644 rust/kernel/acpi.rs
diff --git a/MAINTAINERS b/MAINTAINERS
index 1e918319cff4..3e59a177ac0c 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -302,6 +302,7 @@ F: include/linux/acpi.h
F: include/linux/fwnode.h
F: include/linux/fw_table.h
F: lib/fw_table.c
+F: rust/kernel/acpi.rs
F: tools/power/acpi/
ACPI APEI
diff --git a/rust/kernel/acpi.rs b/rust/kernel/acpi.rs
new file mode 100644
index 000000000000..2b25dc9e07ac
--- /dev/null
+++ b/rust/kernel/acpi.rs
@@ -0,0 +1,60 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Advanced Configuration and Power Interface abstractions.
+
+use crate::{bindings, device_id::RawDeviceId, prelude::*};
+
+/// IdTable type for ACPI drivers.
+pub type IdTable<T> = &'static dyn kernel::device_id::IdTable<DeviceId, T>;
+
+/// An ACPI device id.
+#[repr(transparent)]
+#[derive(Clone, Copy)]
+pub struct DeviceId(bindings::acpi_device_id);
+
+// SAFETY:
+// * `DeviceId` is a `#[repr(transparent)` wrapper of `struct acpi_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::acpi_device_id;
+
+ const DRIVER_DATA_OFFSET: usize = core::mem::offset_of!(bindings::acpi_device_id, driver_data);
+
+ fn index(&self) -> usize {
+ self.0.driver_data as _
+ }
+}
+
+impl DeviceId {
+ const ACPI_ID_LEN: usize = 16;
+
+ /// Create a new device id from an ACPI 'id' string.
+ pub const fn new<const N: usize>(id: &[u8; N]) -> Self {
+ build_assert!(N <= Self::ACPI_ID_LEN, "ID exceeds 16 bytes");
+ // Replace with `bindings::acpi_device_id::default()` once stabilized for `const`.
+ // SAFETY: FFI type is valid to be zero-initialized.
+ let mut acpi: bindings::acpi_device_id = unsafe { core::mem::zeroed() };
+ let mut i = 0;
+ while i < N {
+ acpi.id[i] = id[i];
+ i += 1;
+ }
+
+ Self(acpi)
+ }
+}
+
+/// Create an ACPI `IdTable` with an "alias" for modpost.
+#[macro_export]
+macro_rules! acpi_device_table {
+ ($table_name:ident, $module_table_name:ident, $id_info_type: ty, $table_data: expr) => {
+ const $table_name: $crate::device_id::IdArray<
+ $crate::acpi::DeviceId,
+ $id_info_type,
+ { $table_data.len() },
+ > = $crate::device_id::IdArray::new($table_data);
+
+ $crate::module_device_table!("acpi", $module_table_name, $table_name);
+ };
+}
diff --git a/rust/kernel/lib.rs b/rust/kernel/lib.rs
index 6b4774b2b1c3..5bbf3627212f 100644
--- a/rust/kernel/lib.rs
+++ b/rust/kernel/lib.rs
@@ -51,6 +51,7 @@
pub use ffi;
+pub mod acpi;
pub mod alloc;
#[cfg(CONFIG_AUXILIARY_BUS)]
pub mod auxiliary;
--
2.43.0
