Re: [PATCH v6 6/6] samples: rust: add ACPI match table example to platform driver

[Danilo Krummrich <dakr@kernel.org>]

On Fri, Jun 13, 2025 at 02:54:07PM +0100, Igor Korotin wrote:
> Extend the Rust sample platform driver to probe using device/driver name
> matching, OF ID table matching, or ACPI ID table matching.

Can you please rebase onto driver-core-next? You may also want to add the three
patches I sent as a reply to this one to your series.

> Signed-off-by: Igor Korotin <igor.korotin.linux@gmail.com>
> ---
>  samples/rust/rust_driver_platform.rs | 71 +++++++++++++++++++++++++++-
>  1 file changed, 70 insertions(+), 1 deletion(-)
> 
> diff --git a/samples/rust/rust_driver_platform.rs b/samples/rust/rust_driver_platform.rs
> index 8b42b3cfb363..35d5067aa023 100644
> --- a/samples/rust/rust_driver_platform.rs
> +++ b/samples/rust/rust_driver_platform.rs
> @@ -2,7 +2,7 @@
>  
>  //! Rust Platform driver sample.
>  
> -use kernel::{c_str, device::Core, of, platform, prelude::*, types::ARef};
> +use kernel::{acpi, c_str, device::Core, of, platform, prelude::*, types::ARef};
>  
>  struct SampleDriver {
>      pdev: ARef<platform::Device>,
> @@ -17,9 +17,78 @@ struct SampleDriver {
>      [(of::DeviceId::new(c_str!("test,rust-device")), Info(42))]
>  );
>  
> +// ACPI match table test
> +//
> +// This demonstrates how to test an ACPI-based Rust platform driver using QEMU
> +// with a custom SSDT.
> +//
> +// Steps:
> +//
> +// 1. **Create an SSDT source file** (`ssdt.dsl`) with the following content:
> +//
> +//     ```asl
> +//     DefinitionBlock ("", "SSDT", 2, "TEST", "VIRTACPI", 0x00000001)
> +//     {
> +//         Scope (\_SB)
> +//         {
> +//             Device (T432)
> +//             {
> +//                 Name (_HID, "TEST4321")  // ACPI hardware ID to match
> +//                 Name (_UID, 1)
> +//                 Name (_STA, 0x0F)        // Device present, enabled
> +//                 Name (_CRS, ResourceTemplate ()
> +//                 {
> +//                     Memory32Fixed (ReadWrite, 0xFED00000, 0x1000)
> +//                 })
> +//             }
> +//         }
> +//     }
> +//     ```
> +//
> +// 2. **Compile the table**:
> +//
> +//     ```sh
> +//     iasl -tc ssdt.dsl
> +//     ```
> +//
> +//     This generates `ssdt.aml`
> +//
> +// 3. **Run QEMU** with the compiled AML file:
> +//
> +//     ```sh
> +//     qemu-system-x86_64 -m 512M \
> +//         -enable-kvm \
> +//         -kernel path/to/bzImage \
> +//         -append "root=/dev/sda console=ttyS0" \
> +//         -hda rootfs.img \
> +//         -serial stdio \
> +//         -acpitable file=ssdt.aml
> +//     ```
> +//
> +//     Requirements:
> +//     - The `rust_driver_platform` must be present either:
> +//         - built directly into the kernel (`bzImage`), or
> +//         - available as a `.ko` file and loadable from `rootfs.img`
> +//
> +// 4. **Verify it worked** by checking `dmesg`:
> +//
> +//     ```
> +//     rust_driver_platform TEST4321:00: Probed with info: '0'.
> +//     ```
> +//
> +// This demonstrates ACPI table matching using a custom ID in QEMU with a minimal SSDT

Can you please move this up into the module-level documentation?

> +kernel::acpi_device_table!(
> +    ACPI_TABLE,
> +    MODULE_ACPI_TABLE,
> +    <SampleDriver as platform::Driver>::IdInfo,
> +    [(acpi::DeviceId::new(c_str!("TEST4321")), Info(0))]

Let's use something like "SAMPLE_DRV0" instead.

> +);
> +
>  impl platform::Driver for SampleDriver {
>      type IdInfo = Info;
>      const OF_ID_TABLE: Option<of::IdTable<Self::IdInfo>> = Some(&OF_TABLE);
> +    const ACPI_ID_TABLE: Option<acpi::IdTable<Self::IdInfo>> = Some(&ACPI_TABLE);
>  
>      fn probe(
>          pdev: &platform::Device<Core>,
> -- 
> 2.43.0
>