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// SPDX-License-Identifier: GPL-2.0 OR MIT
//! DRM device.
//!
//! C header: [`include/linux/drm/drm_device.h`](../../../../include/linux/drm/drm_device.h)
use crate::{bindings, device, drm, types::ForeignOwnable};
use core::marker::PhantomData;
/// Represents a reference to a DRM device. The device is reference-counted and is guaranteed to
/// not be dropped while this object is alive.
pub struct Device<T: drm::drv::Driver> {
// Type invariant: ptr must be a valid and initialized drm_device,
// and this value must either own a reference to it or the caller
// must ensure that it is never dropped if the reference is borrowed.
pub(super) ptr: *mut bindings::drm_device,
_p: PhantomData<T>,
}
impl<T: drm::drv::Driver> Device<T> {
// Not intended to be called externally, except via declare_drm_ioctls!()
#[doc(hidden)]
pub unsafe fn from_raw(raw: *mut bindings::drm_device) -> Device<T> {
Device {
ptr: raw,
_p: PhantomData,
}
}
#[allow(dead_code)]
pub(crate) fn raw(&self) -> *const bindings::drm_device {
self.ptr
}
pub(crate) fn raw_mut(&mut self) -> *mut bindings::drm_device {
self.ptr
}
/// Returns a borrowed reference to the user data associated with this Device.
pub fn data(&self) -> <T::Data as ForeignOwnable>::Borrowed<'_> {
unsafe { T::Data::borrow((*self.ptr).dev_private) }
}
}
impl<T: drm::drv::Driver> Drop for Device<T> {
fn drop(&mut self) {
// SAFETY: By the type invariants, we know that `self` owns a reference, so it is safe to
// relinquish it now.
unsafe { bindings::drm_dev_put(self.ptr) };
}
}
impl<T: drm::drv::Driver> Clone for Device<T> {
fn clone(&self) -> Self {
// SAFETY: We get a new reference and then create a new owning object from the raw pointer
unsafe {
bindings::drm_dev_get(self.ptr);
Device::from_raw(self.ptr)
}
}
}
// SAFETY: `Device` only holds a pointer to a C device, which is safe to be used from any thread.
unsafe impl<T: drm::drv::Driver> Send for Device<T> {}
// SAFETY: `Device` only holds a pointer to a C device, references to which are safe to be used
// from any thread.
unsafe impl<T: drm::drv::Driver> Sync for Device<T> {}
// Make drm::Device work for dev_info!() and friends
unsafe impl<T: drm::drv::Driver> device::RawDevice for Device<T> {
fn raw_device(&self) -> *mut bindings::device {
// SAFETY: ptr must be valid per the type invariant
unsafe { (*self.ptr).dev }
}
}
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