mirror of
				https://github.com/torvalds/linux.git
				synced 2025-11-04 02:30:34 +02:00 
			
		
		
		
	Add a sample Rust auxiliary driver based on a PCI driver for QEMU's "pci-testdev" device. The PCI driver only registers an auxiliary device, in order to make the corresponding auxiliary driver probe. Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: https://lore.kernel.org/r/20250414131934.28418-6-dakr@kernel.org [ Use `ok_or()` when accessing auxiliary::Device::parent(). - Danilo ] Signed-off-by: Danilo Krummrich <dakr@kernel.org>
		
			
				
	
	
		
			120 lines
		
	
	
	
		
			3.1 KiB
		
	
	
	
		
			Rust
		
	
	
	
	
	
			
		
		
	
	
			120 lines
		
	
	
	
		
			3.1 KiB
		
	
	
	
		
			Rust
		
	
	
	
	
	
// SPDX-License-Identifier: GPL-2.0
 | 
						|
 | 
						|
//! Rust auxiliary driver sample (based on a PCI driver for QEMU's `pci-testdev`).
 | 
						|
//!
 | 
						|
//! To make this driver probe, QEMU must be run with `-device pci-testdev`.
 | 
						|
 | 
						|
use kernel::{
 | 
						|
    auxiliary, bindings, c_str, device::Core, driver, error::Error, pci, prelude::*, str::CStr,
 | 
						|
    InPlaceModule,
 | 
						|
};
 | 
						|
 | 
						|
use pin_init::PinInit;
 | 
						|
 | 
						|
const MODULE_NAME: &CStr = <LocalModule as kernel::ModuleMetadata>::NAME;
 | 
						|
const AUXILIARY_NAME: &CStr = c_str!("auxiliary");
 | 
						|
 | 
						|
struct AuxiliaryDriver;
 | 
						|
 | 
						|
kernel::auxiliary_device_table!(
 | 
						|
    AUX_TABLE,
 | 
						|
    MODULE_AUX_TABLE,
 | 
						|
    <AuxiliaryDriver as auxiliary::Driver>::IdInfo,
 | 
						|
    [(auxiliary::DeviceId::new(MODULE_NAME, AUXILIARY_NAME), ())]
 | 
						|
);
 | 
						|
 | 
						|
impl auxiliary::Driver for AuxiliaryDriver {
 | 
						|
    type IdInfo = ();
 | 
						|
 | 
						|
    const ID_TABLE: auxiliary::IdTable<Self::IdInfo> = &AUX_TABLE;
 | 
						|
 | 
						|
    fn probe(adev: &auxiliary::Device<Core>, _info: &Self::IdInfo) -> Result<Pin<KBox<Self>>> {
 | 
						|
        dev_info!(
 | 
						|
            adev.as_ref(),
 | 
						|
            "Probing auxiliary driver for auxiliary device with id={}\n",
 | 
						|
            adev.id()
 | 
						|
        );
 | 
						|
 | 
						|
        ParentDriver::connect(adev)?;
 | 
						|
 | 
						|
        let this = KBox::new(Self, GFP_KERNEL)?;
 | 
						|
 | 
						|
        Ok(this.into())
 | 
						|
    }
 | 
						|
}
 | 
						|
 | 
						|
struct ParentDriver {
 | 
						|
    _reg: [auxiliary::Registration; 2],
 | 
						|
}
 | 
						|
 | 
						|
kernel::pci_device_table!(
 | 
						|
    PCI_TABLE,
 | 
						|
    MODULE_PCI_TABLE,
 | 
						|
    <ParentDriver as pci::Driver>::IdInfo,
 | 
						|
    [(
 | 
						|
        pci::DeviceId::from_id(bindings::PCI_VENDOR_ID_REDHAT, 0x5),
 | 
						|
        ()
 | 
						|
    )]
 | 
						|
);
 | 
						|
 | 
						|
impl pci::Driver for ParentDriver {
 | 
						|
    type IdInfo = ();
 | 
						|
 | 
						|
    const ID_TABLE: pci::IdTable<Self::IdInfo> = &PCI_TABLE;
 | 
						|
 | 
						|
    fn probe(pdev: &pci::Device<Core>, _info: &Self::IdInfo) -> Result<Pin<KBox<Self>>> {
 | 
						|
        let this = KBox::new(
 | 
						|
            Self {
 | 
						|
                _reg: [
 | 
						|
                    auxiliary::Registration::new(pdev.as_ref(), AUXILIARY_NAME, 0, MODULE_NAME)?,
 | 
						|
                    auxiliary::Registration::new(pdev.as_ref(), AUXILIARY_NAME, 1, MODULE_NAME)?,
 | 
						|
                ],
 | 
						|
            },
 | 
						|
            GFP_KERNEL,
 | 
						|
        )?;
 | 
						|
 | 
						|
        Ok(this.into())
 | 
						|
    }
 | 
						|
}
 | 
						|
 | 
						|
impl ParentDriver {
 | 
						|
    fn connect(adev: &auxiliary::Device) -> Result<()> {
 | 
						|
        let parent = adev.parent().ok_or(EINVAL)?;
 | 
						|
        let pdev: &pci::Device = parent.try_into()?;
 | 
						|
 | 
						|
        dev_info!(
 | 
						|
            adev.as_ref(),
 | 
						|
            "Connect auxiliary {} with parent: VendorID={:#x}, DeviceID={:#x}\n",
 | 
						|
            adev.id(),
 | 
						|
            pdev.vendor_id(),
 | 
						|
            pdev.device_id()
 | 
						|
        );
 | 
						|
 | 
						|
        Ok(())
 | 
						|
    }
 | 
						|
}
 | 
						|
 | 
						|
#[pin_data]
 | 
						|
struct SampleModule {
 | 
						|
    #[pin]
 | 
						|
    _pci_driver: driver::Registration<pci::Adapter<ParentDriver>>,
 | 
						|
    #[pin]
 | 
						|
    _aux_driver: driver::Registration<auxiliary::Adapter<AuxiliaryDriver>>,
 | 
						|
}
 | 
						|
 | 
						|
impl InPlaceModule for SampleModule {
 | 
						|
    fn init(module: &'static kernel::ThisModule) -> impl PinInit<Self, Error> {
 | 
						|
        try_pin_init!(Self {
 | 
						|
            _pci_driver <- driver::Registration::new(MODULE_NAME, module),
 | 
						|
            _aux_driver <- driver::Registration::new(MODULE_NAME, module),
 | 
						|
        })
 | 
						|
    }
 | 
						|
}
 | 
						|
 | 
						|
module! {
 | 
						|
    type: SampleModule,
 | 
						|
    name: "rust_driver_auxiliary",
 | 
						|
    author: "Danilo Krummrich",
 | 
						|
    description: "Rust auxiliary driver",
 | 
						|
    license: "GPL v2",
 | 
						|
}
 |