Commit f0a68a91 authored by Danilo Krummrich's avatar Danilo Krummrich
Browse files

rust: platform: use generic device drvdata accessors 

Take advantage of the generic drvdata accessors of the generic Device
type.

While at it, use from_result() instead of match.

Link: https://lore.kernel.org/r/20250621195118.124245-4-dakr@kernel.org


Signed-off-by: default avatarDanilo Krummrich <dakr@kernel.org>
parent 880dec12

rust/helpers/platform.c

+0 −10
Original line number Diff line number Diff line
@@ -2,16 +2,6 @@ 


#include <linux/platform_device.h>



void *rust_helper_platform_get_drvdata(const struct platform_device *pdev)

{

	return platform_get_drvdata(pdev);

}



void rust_helper_platform_set_drvdata(struct platform_device *pdev, void *data)

{

	platform_set_drvdata(pdev, data);

}



bool rust_helper_dev_is_platform(const struct device *dev)

{

	return dev_is_platform(dev);

rust/kernel/platform.rs

+17 −19
Original line number Diff line number Diff line
@@ -6,10 +6,10 @@ 


use crate::{

    acpi, bindings, container_of, device, driver,

    error::{to_result, Result},

    error::{from_result, to_result, Result},

    of,

    prelude::*,

    types::{ForeignOwnable, Opaque},

    types::Opaque,

    ThisModule,

};
@@ -66,30 +66,28 @@ extern "C" fn probe_callback(pdev: *mut bindings::platform_device) -> kernel::ff 
        // `struct platform_device`.

        //

        // INVARIANT: `pdev` is valid for the duration of `probe_callback()`.

        let pdev = unsafe { &*pdev.cast::<Device<device::Core>>() };



        let pdev = unsafe { &*pdev.cast::<Device<device::CoreInternal>>() };

        let info = <Self as driver::Adapter>::id_info(pdev.as_ref());

        match T::probe(pdev, info) {

            Ok(data) => {

                // Let the `struct platform_device` own a reference of the driver's private data.

                // SAFETY: By the type invariant `pdev.as_raw` returns a valid pointer to a

                // `struct platform_device`.

                unsafe { bindings::platform_set_drvdata(pdev.as_raw(), data.into_foreign() as _) };

            }

            Err(err) => return Error::to_errno(err),

        }



        0

        from_result(|| {

            let data = T::probe(pdev, info)?;



            pdev.as_ref().set_drvdata(data);

            Ok(0)

        })

    }



    extern "C" fn remove_callback(pdev: *mut bindings::platform_device) {

        // SAFETY: `pdev` is a valid pointer to a `struct platform_device`.

        let ptr = unsafe { bindings::platform_get_drvdata(pdev) }.cast();

        // SAFETY: The platform bus only ever calls the remove callback with a valid pointer to a

        // `struct platform_device`.

        //

        // INVARIANT: `pdev` is valid for the duration of `probe_callback()`.

        let pdev = unsafe { &*pdev.cast::<Device<device::CoreInternal>>() };



        // SAFETY: `remove_callback` is only ever called after a successful call to

        // `probe_callback`, hence it's guaranteed that `ptr` points to a valid and initialized

        // `KBox<T>` pointer created through `KBox::into_foreign`.

        let _ = unsafe { KBox::<T>::from_foreign(ptr) };

        // `probe_callback`, hence it's guaranteed that `Device::set_drvdata()` has been called

        // and stored a `Pin<KBox<T>>`.

        let _ = unsafe { pdev.as_ref().drvdata_obtain::<Pin<KBox<T>>>() };

    }

}