rust: driver: Add ACPI id table support to Adapter trait

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>
This commit is contained in:
Igor Korotin 2025-06-20 16:39:13 +01:00 committed by Danilo Krummrich
parent 0f549d2585
commit 7a5cb145a9
3 changed files with 46 additions and 2 deletions

View File

@ -28,6 +28,7 @@
*/
#include <linux/hrtimer_types.h>
#include <linux/acpi.h>
#include <drm/drm_device.h>
#include <drm/drm_drv.h>
#include <drm/drm_file.h>

View File

@ -6,7 +6,7 @@
//! register using the [`Registration`] class.
use crate::error::{Error, Result};
use crate::{device, of, str::CStr, try_pin_init, types::Opaque, ThisModule};
use crate::{acpi, device, of, str::CStr, try_pin_init, types::Opaque, ThisModule};
use core::pin::Pin;
use pin_init::{pin_data, pinned_drop, PinInit};
@ -141,6 +141,40 @@ pub trait Adapter {
/// The type holding driver private data about each device id supported by the driver.
type IdInfo: 'static;
/// The [`acpi::IdTable`] of the corresponding driver
fn acpi_id_table() -> Option<acpi::IdTable<Self::IdInfo>>;
/// Returns the driver's private data from the matching entry in the [`acpi::IdTable`], if any.
///
/// If this returns `None`, it means there is no match with an entry in the [`acpi::IdTable`].
fn acpi_id_info(dev: &device::Device) -> Option<&'static Self::IdInfo> {
#[cfg(not(CONFIG_ACPI))]
{
let _ = dev;
None
}
#[cfg(CONFIG_ACPI)]
{
let table = Self::acpi_id_table()?;
// SAFETY:
// - `table` has static lifetime, hence it's valid for read,
// - `dev` is guaranteed to be valid while it's alive, and so is `dev.as_raw()`.
let raw_id = unsafe { bindings::acpi_match_device(table.as_ptr(), dev.as_raw()) };
if raw_id.is_null() {
None
} else {
// SAFETY: `DeviceId` is a `#[repr(transparent)` wrapper of `struct acpi_device_id`
// and does not add additional invariants, so it's safe to transmute.
let id = unsafe { &*raw_id.cast::<acpi::DeviceId>() };
Some(table.info(<acpi::DeviceId as crate::device_id::RawDeviceId>::index(id)))
}
}
}
/// The [`of::IdTable`] of the corresponding driver.
fn of_id_table() -> Option<of::IdTable<Self::IdInfo>>;
@ -180,6 +214,11 @@ fn of_id_info(dev: &device::Device) -> Option<&'static Self::IdInfo> {
/// If this returns `None`, it means that there is no match in any of the ID tables directly
/// associated with a [`device::Device`].
fn id_info(dev: &device::Device) -> Option<&'static Self::IdInfo> {
let id = Self::acpi_id_info(dev);
if id.is_some() {
return id;
}
let id = Self::of_id_info(dev);
if id.is_some() {
return id;

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@ -5,7 +5,7 @@
//! C header: [`include/linux/platform_device.h`](srctree/include/linux/platform_device.h)
use crate::{
bindings, container_of, device, driver,
acpi, bindings, container_of, device, driver,
error::{to_result, Result},
of,
prelude::*,
@ -94,6 +94,10 @@ impl<T: Driver + 'static> driver::Adapter for Adapter<T> {
fn of_id_table() -> Option<of::IdTable<Self::IdInfo>> {
T::OF_ID_TABLE
}
fn acpi_id_table() -> Option<acpi::IdTable<Self::IdInfo>> {
None
}
}
/// Declares a kernel module that exposes a single platform driver.