Documentation/driver-api/infrastructure.rst

@@ -41,6 +41,12 @@ Device Drivers Base
 .. kernel-doc:: drivers/base/class.c
    :export:
 
+.. kernel-doc:: include/linux/device/faux.h
+   :internal:
+
+.. kernel-doc:: drivers/base/faux.c
+   :export:
+
 .. kernel-doc:: drivers/base/node.c
    :internal:
 

MAINTAINERS

@@ -6985,8 +6985,10 @@ F:	rust/kernel/device.rs
 F:	rust/kernel/device_id.rs
 F:	rust/kernel/devres.rs
 F:	rust/kernel/driver.rs
+F:	rust/kernel/faux.rs
 F:	rust/kernel/platform.rs
 F:	samples/rust/rust_driver_platform.rs
+F:	samples/rust/rust_driver_faux.rs
 DRIVERS FOR OMAP ADAPTIVE VOLTAGE SCALING (AVS)
 M:	Nishanth Menon <nm@ti.com>

drivers/base/Makefile

@@ -6,7 +6,7 @@ obj-y			:= component.o core.o bus.o dd.o syscore.o \
 			   cpu.o firmware.o init.o map.o devres.o \
 			   attribute_container.o transport_class.o \
 			   topology.o container.o property.o cacheinfo.o \
-			   swnode.o
+			   swnode.o faux.o
 obj-$(CONFIG_AUXILIARY_BUS) += auxiliary.o
 obj-$(CONFIG_DEVTMPFS)	+= devtmpfs.o
 obj-y			+= power/

drivers/base/base.h

@@ -137,6 +137,7 @@ int hypervisor_init(void);
 static inline int hypervisor_init(void) { return 0; }
 #endif
 int platform_bus_init(void);
+int faux_bus_init(void);
 void cpu_dev_init(void);
 void container_dev_init(void);
 #ifdef CONFIG_AUXILIARY_BUS

drivers/base/faux.c

+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2025 Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+ * Copyright (c) 2025 The Linux Foundation
+ *
+ * A "simple" faux bus that allows devices to be created and added
+ * automatically to it.  This is to be used whenever you need to create a
+ * device that is not associated with any "real" system resources, and do
+ * not want to have to deal with a bus/driver binding logic.  It is
+ * intended to be very simple, with only a create and a destroy function
+ * available.
+ */
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/container_of.h>
+#include <linux/device/faux.h>
+#include "base.h"
+
+/*
+ * Internal wrapper structure so we can hold a pointer to the
+ * faux_device_ops for this device.
+ */
+struct faux_object {
+	struct faux_device faux_dev;
+	const struct faux_device_ops *faux_ops;
+};
+#define to_faux_object(dev) container_of_const(dev, struct faux_object, faux_dev.dev)
+
+static struct device faux_bus_root = {
+	.init_name	= "faux",
+};
+
+static int faux_match(struct device *dev, const struct device_driver *drv)
+{
+	/* Match always succeeds, we only have one driver */
+	return 1;
+}
+
+static int faux_probe(struct device *dev)
+{
+	struct faux_object *faux_obj = to_faux_object(dev);
+	struct faux_device *faux_dev = &faux_obj->faux_dev;
+	const struct faux_device_ops *faux_ops = faux_obj->faux_ops;
+	int ret = 0;
+
+	if (faux_ops && faux_ops->probe)
+		ret = faux_ops->probe(faux_dev);
+
+	return ret;
+}
+
+static void faux_remove(struct device *dev)
+{
+	struct faux_object *faux_obj = to_faux_object(dev);
+	struct faux_device *faux_dev = &faux_obj->faux_dev;
+	const struct faux_device_ops *faux_ops = faux_obj->faux_ops;
+
+	if (faux_ops && faux_ops->remove)
+		faux_ops->remove(faux_dev);
+}
+
+static const struct bus_type faux_bus_type = {
+	.name		= "faux",
+	.match		= faux_match,
+	.probe		= faux_probe,
+	.remove		= faux_remove,
+};
+
+static struct device_driver faux_driver = {
+	.name		= "faux_driver",
+	.bus		= &faux_bus_type,
+	.probe_type	= PROBE_FORCE_SYNCHRONOUS,
+};
+
+static void faux_device_release(struct device *dev)
+{
+	struct faux_object *faux_obj = to_faux_object(dev);
+
+	kfree(faux_obj);
+}
+
+/**
+ * faux_device_create_with_groups - Create and register with the driver
+ *		core a faux device and populate the device with an initial
+ *		set of sysfs attributes.
+ * @name:	The name of the device we are adding, must be unique for
+ *		all faux devices.
+ * @parent:	Pointer to a potential parent struct device.  If set to
+ *		NULL, the device will be created in the "root" of the faux
+ *		device tree in sysfs.
+ * @faux_ops:	struct faux_device_ops that the new device will call back
+ *		into, can be NULL.
+ * @groups:	The set of sysfs attributes that will be created for this
+ *		device when it is registered with the driver core.
+ *
+ * Create a new faux device and register it in the driver core properly.
+ * If present, callbacks in @faux_ops will be called with the device that
+ * for the caller to do something with at the proper time given the
+ * device's lifecycle.
+ *
+ * Note, when this function is called, the functions specified in struct
+ * faux_ops can be called before the function returns, so be prepared for
+ * everything to be properly initialized before that point in time.
+ *
+ * Return:
+ * * NULL if an error happened with creating the device
+ * * pointer to a valid struct faux_device that is registered with sysfs
+ */
+struct faux_device *faux_device_create_with_groups(const char *name,
+						   struct device *parent,
+						   const struct faux_device_ops *faux_ops,
+						   const struct attribute_group **groups)
+{
+	struct faux_object *faux_obj;
+	struct faux_device *faux_dev;
+	struct device *dev;
+	int ret;
+
+	faux_obj = kzalloc(sizeof(*faux_obj), GFP_KERNEL);
+	if (!faux_obj)
+		return NULL;
+
+	/* Save off the callbacks so we can use them in the future */
+	faux_obj->faux_ops = faux_ops;
+
+	/* Initialize the device portion and register it with the driver core */
+	faux_dev = &faux_obj->faux_dev;
+	dev = &faux_dev->dev;
+
+	device_initialize(dev);
+	dev->release = faux_device_release;
+	if (parent)
+		dev->parent = parent;
+	else
+		dev->parent = &faux_bus_root;
+	dev->bus = &faux_bus_type;
+	dev->groups = groups;
+	dev_set_name(dev, "%s", name);
+
+	ret = device_add(dev);
+	if (ret) {
+		pr_err("%s: device_add for faux device '%s' failed with %d\n",
+		       __func__, name, ret);
+		put_device(dev);
+		return NULL;
+	}
+
+	return faux_dev;
+}
+EXPORT_SYMBOL_GPL(faux_device_create_with_groups);
+
+/**
+ * faux_device_create - create and register with the driver core a faux device
+ * @name:	The name of the device we are adding, must be unique for all
+ *		faux devices.
+ * @parent:	Pointer to a potential parent struct device.  If set to
+ *		NULL, the device will be created in the "root" of the faux
+ *		device tree in sysfs.
+ * @faux_ops:	struct faux_device_ops that the new device will call back
+ *		into, can be NULL.
+ *
+ * Create a new faux device and register it in the driver core properly.
+ * If present, callbacks in @faux_ops will be called with the device that
+ * for the caller to do something with at the proper time given the
+ * device's lifecycle.
+ *
+ * Note, when this function is called, the functions specified in struct
+ * faux_ops can be called before the function returns, so be prepared for
+ * everything to be properly initialized before that point in time.
+ *
+ * Return:
+ * * NULL if an error happened with creating the device
+ * * pointer to a valid struct faux_device that is registered with sysfs
+ */
+struct faux_device *faux_device_create(const char *name,
+				       struct device *parent,
+				       const struct faux_device_ops *faux_ops)
+{
+	return faux_device_create_with_groups(name, parent, faux_ops, NULL);
+}
+EXPORT_SYMBOL_GPL(faux_device_create);
+
+/**
+ * faux_device_destroy - destroy a faux device
+ * @faux_dev:	faux device to destroy
+ *
+ * Unregisters and cleans up a device that was created with a call to
+ * faux_device_create()
+ */
+void faux_device_destroy(struct faux_device *faux_dev)
+{
+	struct device *dev = &faux_dev->dev;
+
+	if (!faux_dev)
+		return;
+
+	device_del(dev);
+
+	/* The final put_device() will clean up the memory we allocated for this device. */
+	put_device(dev);
+}
+EXPORT_SYMBOL_GPL(faux_device_destroy);
+
+int __init faux_bus_init(void)
+{
+	int ret;
+
+	ret = device_register(&faux_bus_root);
+	if (ret) {
+		put_device(&faux_bus_root);
+		return ret;
+	}
+
+	ret = bus_register(&faux_bus_type);
+	if (ret)
+		goto error_bus;
+
+	ret = driver_register(&faux_driver);
+	if (ret)
+		goto error_driver;
+
+	return ret;
+
+error_driver:
+	bus_unregister(&faux_bus_type);
+
+error_bus:
+	device_unregister(&faux_bus_root);
+	return ret;
+}

drivers/base/init.c

@@ -32,6 +32,7 @@ void __init driver_init(void)
 	/* These are also core pieces, but must come after the
 	 * core core pieces.
 	 */
+	faux_bus_init();
 	of_core_init();
 	platform_bus_init();
 	auxiliary_bus_init();

drivers/gpu/drm/Kconfig

@@ -354,6 +354,8 @@ source "drivers/gpu/drm/amd/amdgpu/Kconfig"
 
 source "drivers/gpu/drm/nouveau/Kconfig"
 
+source "drivers/gpu/drm/rvkms/Kconfig"
+
 source "drivers/gpu/drm/i915/Kconfig"
 
 source "drivers/gpu/drm/xe/Kconfig"

drivers/gpu/drm/Makefile

@@ -172,6 +172,7 @@ obj-$(CONFIG_DRM_VMWGFX)+= vmwgfx/
 obj-$(CONFIG_DRM_VGEM)	+= vgem/
 obj-$(CONFIG_DRM_VKMS)	+= vkms/
 obj-$(CONFIG_DRM_NOUVEAU) +=nouveau/
+obj-$(CONFIG_DRM_RVKMS) += rvkms/
 obj-$(CONFIG_DRM_EXYNOS) +=exynos/
 obj-$(CONFIG_DRM_ROCKCHIP) +=rockchip/
 obj-$(CONFIG_DRM_GMA500) += gma500/

drivers/gpu/drm/drm_connector.c

@@ -88,7 +88,7 @@ struct drm_conn_prop_enum_list {
 /*
  * Connector and encoder types.
  */
-static struct drm_conn_prop_enum_list drm_connector_enum_list[] = {
+static struct drm_conn_prop_enum_list drm_connector_enum_list[_DRM_MODE_CONNECTOR_COUNT] = {
 	{ DRM_MODE_CONNECTOR_Unknown, "Unknown" },
 	{ DRM_MODE_CONNECTOR_VGA, "VGA" },
 	{ DRM_MODE_CONNECTOR_DVII, "DVI-I" },

drivers/gpu/drm/drm_gem_shmem_helper.c

@@ -509,7 +509,7 @@ int drm_gem_shmem_dumb_create(struct drm_file *file, struct drm_device *dev,
 }
 EXPORT_SYMBOL_GPL(drm_gem_shmem_dumb_create);
 
-static vm_fault_t drm_gem_shmem_fault(struct vm_fault *vmf)
+vm_fault_t drm_gem_shmem_fault(struct vm_fault *vmf)
 {
 	struct vm_area_struct *vma = vmf->vma;
 	struct drm_gem_object *obj = vma->vm_private_data;
@@ -538,8 +538,9 @@ static vm_fault_t drm_gem_shmem_fault(struct vm_fault *vmf)
 
 	return ret;
 }
+EXPORT_SYMBOL_GPL(drm_gem_shmem_fault);
 
-static void drm_gem_shmem_vm_open(struct vm_area_struct *vma)
+void drm_gem_shmem_vm_open(struct vm_area_struct *vma)
 {
 	struct drm_gem_object *obj = vma->vm_private_data;
 	struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
@@ -560,8 +561,9 @@ static void drm_gem_shmem_vm_open(struct vm_area_struct *vma)
 
 	drm_gem_vm_open(vma);
 }
+EXPORT_SYMBOL_GPL(drm_gem_shmem_vm_open);
 
-static void drm_gem_shmem_vm_close(struct vm_area_struct *vma)
+void drm_gem_shmem_vm_close(struct vm_area_struct *vma)
 {
 	struct drm_gem_object *obj = vma->vm_private_data;
 	struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
@@ -572,6 +574,7 @@ static void drm_gem_shmem_vm_close(struct vm_area_struct *vma)
 
 	drm_gem_vm_close(vma);
 }
+EXPORT_SYMBOL_GPL(drm_gem_shmem_vm_close);
 
 const struct vm_operations_struct drm_gem_shmem_vm_ops = {
 	.fault = drm_gem_shmem_fault,

drivers/gpu/drm/rvkms/Kconfig

+config DRM_RVKMS
+        tristate "Rust VKMS PoC driver (EXPERIMENTAL)"
+        depends on RUST && DRM && DRM_GEM_SHMEM_HELPER=y

drivers/gpu/drm/rvkms/Makefile

+obj-$(CONFIG_DRM_RVKMS) += rvkms.o

drivers/gpu/drm/rvkms/connector.rs

+// SPDX-License-Identifier: GPL-2.0
+use super::{RvkmsDriver, RvkmsDevice, MAX_RES, DEFAULT_RES};
+use kernel::{
+    prelude::*,
+    drm::{
+        device::Device,
+        kms::{
+            connector::{self, ConnectorGuard, DriverConnectorOps},
+            ModeConfigGuard
+        }
+    },
+    prelude::*
+};
+use core::marker::PhantomPinned;
+
+#[pin_data]
+pub(crate) struct DriverConnector {
+    #[pin]
+    _p: PhantomPinned
+}
+
+pub(crate) type Connector = connector::Connector<DriverConnector>;
+pub(crate) type UnregisteredConnector = connector::UnregisteredConnector<DriverConnector>;
+
+#[vtable]
+impl connector::DriverConnector for DriverConnector {
+    #[unique]
+    const OPS: &'static DriverConnectorOps;
+
+    type State = ConnectorState;
+    type Driver = RvkmsDriver;
+    type Args = ();
+
+    fn new(dev: &Device<Self::Driver>, args: Self::Args) -> impl PinInit<Self, Error> {
+        try_pin_init!(Self { _p: PhantomPinned })
+    }
+
+    fn get_modes(
+        connector: ConnectorGuard<'_, Self>,
+        _guard: &ModeConfigGuard<'_, Self::Driver>
+    ) -> i32 {
+        let count = connector.add_modes_noedid(MAX_RES);
+
+        connector.set_preferred_mode(DEFAULT_RES);
+        count
+    }
+}
+
+#[derive(Clone, Default)]
+pub(crate) struct ConnectorState;
+
+impl connector::DriverConnectorState for ConnectorState {
+    type Connector = DriverConnector;
+}

drivers/gpu/drm/rvkms/crtc.rs

+// TODO: License and stuff
+// Contain's rvkms's drm_crtc implementation
+use core::marker::*;
+use super::{RvkmsDriver, plane::*};
+use kernel::{
+    prelude::*,
+    drm::{
+        device::Device,
+        kms::{
+            atomic::*,
+            crtc::{self, RawCrtcState, DriverCrtcOps},
+            ModeObject,
+            KmsRef,
+            vblank::*,
+        }
+    },
+    sync::{
+        lock::Guard,
+        SpinLockIrq,
+        LockedBy,
+    },
+    hrtimer::*,
+    time::*,
+    local_irq::*,
+    sync::{Arc, ArcBorrow},
+    new_spinlock_irq,
+    impl_has_timer
+};
+
+pub(crate) type Crtc = crtc::Crtc<RvkmsCrtc>;
+pub(crate) type UnregisteredCrtc = crtc::UnregisteredCrtc<RvkmsCrtc>;
+pub(crate) type CrtcState = crtc::CrtcState<RvkmsCrtcState>;
+
+#[derive(Default)]
+pub(crate) struct VblankState {
+    /// A reference to the current VblankTimer
+    timer: Option<Arc<VblankTimer>>,
+
+    /// A reference to a handle for the current VblankTimer
+    handle: Option<ArcTimerHandle<VblankTimer>>,
+
+    /// The current frame duration in ns
+    ///
+    /// Stored separately here so it can be read safely without the vblank lock
+    period_ns: i32,
+}
+
+#[pin_data]
+pub(crate) struct RvkmsCrtc {
+    /// The current vblank emulation state
+    ///
+    /// This is uninitalized when the CRTC is disabled to prevent circular references
+    #[pin]
+    vblank_state: SpinLockIrq<VblankState>
+}
+
+#[vtable]
+impl crtc::DriverCrtc for RvkmsCrtc {
+    #[unique]
+    const OPS: &'static DriverCrtcOps;
+
+    type Args = ();
+    type State = RvkmsCrtcState;
+    type Driver = RvkmsDriver;
+    type VblankImpl = Self;
+
+    fn new(device: &Device<Self::Driver>, args: &Self::Args) -> impl PinInit<Self, Error> {
+        try_pin_init!(Self {
+            vblank_state <- new_spinlock_irq!(VblankState::default(), "vblank_handle_lock")
+        })
+    }
+
+    fn atomic_check(
+        crtc: &Crtc,
+        old_state: &CrtcState,
+        mut new_state: crtc::CrtcStateMutator<'_, CrtcState>,
+        state: &AtomicStateComposer<Self::Driver>
+    ) -> Result {
+        state.add_affected_planes(crtc)?;
+
+        // Create a vblank timer when enabling a CRTC, and destroy said timer when disabling to
+        // resolve the circular reference to CRTC it creates
+        if old_state.active() != new_state.active() {
+            new_state.vblank_timer = if new_state.active() {
+                Some(VblankTimer::new(crtc)?)
+            } else {
+                None
+            };
+        }
+
+        Ok(())
+    }
+
+    fn atomic_flush(
+        crtc: &Crtc,
+        _old_state: &CrtcState,
+        mut new_state: crtc::CrtcStateMutator<'_, CrtcState>,
+        _state: &AtomicStateMutator<Self::Driver>
+    ) {
+        if let Some(event) = new_state.get_pending_vblank_event() {
+            if let Ok(vbl_ref) = crtc.vblank_get() {
+                event.arm(vbl_ref);
+            } else {
+                event.send();
+            }
+        }
+    }
+
+    fn atomic_enable(
+        crtc: &Crtc,
+        old_state: &CrtcState,
+        new_state: crtc::CrtcStateMutator<'_, CrtcState>,
+        _state: &AtomicStateMutator<Self::Driver>
+    ) {
+        crtc.vblank_state.lock_with_new(|state, _| {
+            // Store a reference to the newly created vblank timer for this CRTC
+            state.timer = new_state.vblank_timer.clone()
+        });
+
+        crtc.vblank_on();
+    }
+
+    fn atomic_disable(
+        crtc: &Crtc,
+        _old_state: &CrtcState,
+        _new_state: crtc::CrtcStateMutator<'_, CrtcState>,
+        _state: &AtomicStateMutator<Self::Driver>
+    ) {
+        crtc.vblank_off();
+
+        // Since we just explicitly disabled vblanks, destroy the vblank state to resolve circular
+        // reference to this CRTC that it holds. Note that dropping the handle will cause us to wait
+        // for the timer to finish, so we return it from with_irqs_disabled so that it is only
+        // dropped once the vblank_state lock has been released
+        drop(crtc.vblank_state.lock_with_new(|mut state, _| {
+            (state.timer.take(), state.handle.take())
+        }));
+    }
+}
+
+impl VblankSupport for RvkmsCrtc {
+    type Crtc = Self;
+
+    fn enable_vblank(
+        crtc: &Crtc,
+        vblank: &VblankGuard<'_, Self::Crtc>,
+        irq: IrqDisabled<'_>,
+    ) -> Result {
+        let period_ns = vblank.frame_duration();
+        let mut vbl_state = crtc.vblank_state.lock_with(irq);
+
+        if let Some(timer) = vbl_state.timer.clone() {
+            vbl_state.period_ns = period_ns;
+            vbl_state.handle = Some(timer.start(Ktime::from_raw(period_ns as _)));
+        }
+
+        Ok(())
+    }
+
+    fn disable_vblank(crtc: &Crtc, _vbl_guard: &VblankGuard<'_, Self::Crtc>, irq: IrqDisabled<'_>) {
+        let handle = crtc.vblank_state.lock_with(irq).handle.take();
+
+        // Now that we're outside of the vblank lock, we can safely drop the handle
+        drop(handle);
+    }
+
+    fn get_vblank_timestamp(crtc: &Crtc, _handling_vblank_irq: bool) -> Option<VblankTimestamp> {
+        let time = crtc.vblank_state.lock_with_new(|state, _| {
+            // Return the expiration of our vblank timer if we have one (if not, vblanks are
+            // disabled)
+            state.timer.as_ref().map(|t| {
+                // To prevent races, we roll the hrtimer forward before we do any interrupt
+                // processing - this is how real hw works (the interrupt is only generated after all
+                // the vblank registers are updated) and what the vblank core expects. Therefore we
+                // need to always correct the timestamps by one frame.
+                t.timer.expires() - Ktime::from_ns(state.period_ns)
+            })
+        });
+
+        Some(VblankTimestamp {
+            // …otherwise, just use the current time
+            time: time.unwrap_or_else(|| Ktime::ktime_get()),
+            max_error: 0
+        })
+    }
+}
+
+#[derive(Clone, Default)]
+pub(crate) struct RvkmsCrtcState {
+    vblank_timer: Option<Arc<VblankTimer>>
+}
+
+impl crtc::DriverCrtcState for RvkmsCrtcState {
+    type Crtc = RvkmsCrtc;
+}
+
+/// The main hrtimer structure for emulating vblanks.
+#[pin_data]
+pub(crate) struct VblankTimer {
+    /// The actual hrtimer used for sending out vblanks
+    #[pin]
+    timer: Timer<Self>,
+
+    /// An owned reference to the CRTC that this [`VblankTimer`] belongs to
+    crtc: KmsRef<Crtc>,
+}
+
+impl_has_timer! {
+    impl HasTimer<Self> for VblankTimer { self.timer }
+}
+
+impl VblankTimer {
+    pub(crate) fn new(crtc: &Crtc) -> Result<Arc<Self>> {
+        Arc::pin_init(
+            pin_init!(Self {
+                timer <- Timer::<Self>::new(TimerMode::Relative, ClockSource::Monotonic),
+                crtc: crtc.into(),
+            }),
+            GFP_KERNEL
+        )
+    }
+}
+
+impl TimerCallback for VblankTimer {
+    type CallbackTarget<'a> = Arc<Self>;
+    type CallbackTargetParameter<'a> = ArcBorrow<'a, Self>;
+
+    fn run<T>(
+        this: Self::CallbackTargetParameter<'_>,
+        context: TimerCallbackContext<'_, T>
+    ) -> TimerRestart
+    where
+        Self: Sized
+    {
+        let period_ns = this.crtc.vblank_state.lock_with_new(|guard, _| guard.period_ns);
+
+        let overrun = context.forward_now(Ktime::from_ns(period_ns));
+        if overrun != 1 {
+            dev_warn!(
+                this.crtc.drm_dev().as_ref(),
+                "vblank timer overrun (expected 1, got {overrun})\n"
+            );
+        }
+
+        this.crtc.handle_vblank();
+
+        TimerRestart::Restart
+    }
+}

drivers/gpu/drm/rvkms/encoder.rs

+// SPDX-License-Identifier: GPL-2.0
+use core::marker::PhantomPinned;
+use kernel::{
+    drm::{device::Device, kms::encoder},
+    prelude::*,
+};
+use crate::RvkmsDriver;
+
+#[pin_data]
+pub(crate) struct DriverEncoder {
+    #[pin]
+    _p: PhantomPinned,
+}
+
+pub(crate) type Encoder = encoder::Encoder<DriverEncoder>;
+pub(crate) type UnregisteredEncoder = encoder::UnregisteredEncoder<DriverEncoder>;
+
+#[vtable]
+impl encoder::DriverEncoder for DriverEncoder {
+    #[unique]
+    const OPS: &'static encoder::DriverEncoderOps;
+
+    type Driver = RvkmsDriver;
+    type Args = ();
+
+    fn new(device: &Device<Self::Driver>, args: Self::Args) -> impl PinInit<Self, Error> {
+        try_pin_init!(Self { _p: PhantomPinned })
+    }
+}

drivers/gpu/drm/rvkms/file.rs

+use super::RvkmsDriver;
+
+use kernel::{
+    alloc::*,
+    drm::{
+        self,
+        device::Device as DrmDevice
+    },
+    prelude::*,
+};
+use core::option::*;
+
+pub(crate) struct File;
+
+impl drm::file::DriverFile for File {
+    type Driver = RvkmsDriver;
+
+    fn open(device: &DrmDevice<Self::Driver>) -> Result<Pin<KBox<Self>>> {
+        pr_info!("Someone opened a file! But I do not yet know which one...\n");
+
+        Box::pin_init(init!(File { }), GFP_KERNEL)
+    }
+}

drivers/gpu/drm/rvkms/gem.rs

+use crate::{RvkmsDriver, RvkmsDevice};
+use core::sync::atomic::{AtomicU64, Ordering};
+use kernel::{
+    drm::{self, gem},
+    prelude::*,
+};
+
+static GEM_ID: AtomicU64 = AtomicU64::new(0);
+
+/// GEM Object implementation
+#[pin_data]
+pub(crate) struct DriverObject {
+    /// ID for debugging
+    id: u64,
+}
+
+pub(crate) type Object = gem::shmem::Object<DriverObject>;
+
+impl gem::BaseDriverObject<Object> for DriverObject {
+    fn new(dev: &RvkmsDevice, size: usize) -> impl PinInit<Self, Error> {
+        let id = GEM_ID.fetch_add(1, Ordering::Relaxed);
+
+        pr_debug!("DriverObject::new id={id}\n");
+        DriverObject { id }
+    }
+}
+
+impl gem::shmem::DriverObject for DriverObject {
+    type Driver = RvkmsDriver;
+}

drivers/gpu/drm/rvkms/output.rs

+// SPDX-License-Identifier: GPL-2.0
+use crate::{
+    crtc::UnregisteredCrtc,
+    plane::UnregisteredPlane,
+    connector::UnregisteredConnector,
+    encoder::UnregisteredEncoder,
+    RvkmsDevice,
+    RvkmsDriver
+};
+use kernel::{
+    drm::{
+        fourcc::*,
+        kms::{
+            connector,
+            encoder,
+            plane,
+            framebuffer::*,
+            UnregisteredKmsDevice,
+        },
+    },
+    sync::Arc,
+    prelude::*,
+    types::ARef,
+};
+
+pub(crate) fn create_output(dev: &UnregisteredKmsDevice<'_, RvkmsDriver>, index: u8) -> Result {
+    let possible_crtcs = 1 << index;
+
+    let primary = UnregisteredPlane::new(
+        dev,
+        possible_crtcs,
+        &[XRGB888],
+        None,
+        plane::Type::Primary,
+        None,
+        ()
+    )?;
+
+    let crtc = UnregisteredCrtc::new(dev, primary, Option::<&UnregisteredPlane>::None, None, ())?;
+
+    let connector = UnregisteredConnector::new(dev, connector::Type::Virtual, ())?;
+
+    let encoder = UnregisteredEncoder::new(
+        dev,
+        encoder::Type::Virtual,
+        possible_crtcs,
+        0,
+        None,
+        ()
+    )?;
+
+    connector.attach_encoder(encoder)
+}

drivers/gpu/drm/rvkms/plane.rs

+// SPDX-License-Identifier: GPL-2.0
+use core::marker::PhantomPinned;
+use super::{RvkmsDriver, crtc::{RvkmsCrtc, Crtc}};
+use kernel::{
+    prelude::*,
+    drm::{
+        device::Device,
+        kms::{
+            atomic::*,
+            plane::{
+                self,
+                AsRawPlaneState,
+                FromRawPlaneState,
+                DriverPlaneState,
+                RawPlane,
+                RawPlaneState,
+                PlaneStateMutator,
+                DriverPlaneOps,
+            },
+            ModeObject
+        }
+    },
+};
+
+#[pin_data]
+pub(crate) struct RvkmsPlane {
+    #[pin]
+    _p: PhantomPinned,
+}
+
+pub(crate) type Plane = plane::Plane<RvkmsPlane>;
+pub(crate) type UnregisteredPlane = plane::UnregisteredPlane<RvkmsPlane>;
+pub(crate) type PlaneState = plane::PlaneState<RvkmsPlaneState>;
+
+#[vtable]
+impl plane::DriverPlane for RvkmsPlane {
+    #[unique]
+    const OPS: &'static DriverPlaneOps;
+
+    type State = RvkmsPlaneState;
+    type Driver = RvkmsDriver;
+    type Args = ();
+
+    fn new(device: &Device<Self::Driver>, args: Self::Args) -> impl PinInit<Self, Error> {
+        try_pin_init!(Self { _p: PhantomPinned })
+    }
+
+    fn atomic_check(
+        plane: &Plane,
+        mut new_state: PlaneStateMutator<'_, PlaneState>,
+        _old_state: &PlaneState,
+        state: &AtomicStateComposer<Self::Driver>
+    ) -> Result {
+        if new_state.framebuffer().is_none() {
+            return Ok(());
+        }
+
+        if let Some(crtc) = new_state.crtc() {
+            let crtc_state = state.add_crtc_state(crtc)?;
+            new_state.atomic_helper_check(&crtc_state, true, true)
+        } else {
+            // TODO: We should be printing a warning here if we have no CRTC but do have an fb
+            return Ok(());
+        }
+    }
+
+    fn atomic_update(
+        _plane: &Plane,
+        _new_state: PlaneStateMutator<'_, PlaneState>,
+        _old_state: &PlaneState,
+        _state: &AtomicStateMutator<Self::Driver>,
+    ) {
+        // TODO, no-op for now
+    }
+}
+
+#[derive(Clone, Default)]
+pub(crate) struct RvkmsPlaneState;
+
+impl DriverPlaneState for RvkmsPlaneState {
+    type Plane = RvkmsPlane;
+}

drivers/gpu/drm/rvkms/rvkms.rs

+// SPDX-License-Identifier: GPL-2.0
+mod connector;
+mod crtc;
+mod file;
+mod gem;
+mod plane;
+mod output;
+mod encoder;
+
+use core::{option::*, marker::*};
+
+use kernel::{
+    c_str,
+    str::CStr,
+    device,
+    driver,
+    drm::{
+        self,
+        drv,
+        kms::{
+            KmsDriver,
+            ModeConfigInfo,
+            UnregisteredKmsDevice,
+            atomic::*,
+        },
+    },
+    faux,
+    prelude::*,
+    sync::Arc,
+    of,
+    alloc::*,
+};
+
+/// Convienence type alias for the DRM device type for this driver
+pub(crate) type RvkmsDevice = drm::device::Device<RvkmsDriver>;
+
+/// The name of the driver
+const NAME: &'static CStr = c_str!("rvkms");
+
+/// Driver metadata
+const INFO: drv::DriverInfo = drv::DriverInfo {
+    major: 0,
+    minor: 0,
+    patchlevel: 0,
+    name: &NAME,
+    desc: c_str!("Rust VKMS PoC"),
+    date: c_str!("20240115"),
+};
+
+/// The minimum supported resolution
+const MIN_RES: (i32, i32) = (10, 10);
+
+/// The maximum supported resolution
+const MAX_RES: (i32, i32) = (8192, 8192);
+
+/// The "preferred" resolution
+const DEFAULT_RES: (i32, i32) = (1024, 768);
+
+/// DRM Driver implementation for `RvkmsDriver`
+#[vtable]
+impl drv::Driver for RvkmsDriver {
+    type Data = ();
+    type Object = gem::Object;
+    type File = file::File;
+    type Kms = Self;
+
+    const INFO: drv::DriverInfo = INFO;
+    const FEATURES:u32 = drv::FEAT_GEM | drv::FEAT_MODESET | drv::FEAT_ATOMIC;
+
+    kernel::declare_drm_ioctls! {}
+}
+
+#[vtable]
+impl KmsDriver for RvkmsDriver {
+    fn mode_config_info(
+        _dev: &device::Device,
+        _drm_data: <Self::Data as kernel::types::ForeignOwnable>::Borrowed<'_>,
+    ) -> Result<ModeConfigInfo> {
+        Ok(MODE_CONFIG_INFO)
+    }
+
+    fn create_objects(drm: &UnregisteredKmsDevice<'_, Self>) -> Result
+    where
+        Self: Sized
+    {
+        output::create_output(drm, 0)
+    }
+
+    fn atomic_commit_tail<'a>(
+        mut state: AtomicCommitTail<'a, Self>,
+        modeset_token: ModesetsReadyToken<'_>,
+        plane_update_token: PlaneUpdatesReadyToken<'_>,
+    ) -> CommittedAtomicState<'a, Self>
+    where
+        Self: Sized
+    {
+        let modeset_token = state.commit_modeset_disables(modeset_token);
+
+        let plane_update_token = state.commit_planes(plane_update_token, Default::default());
+
+        let modeset_token = state.commit_modeset_enables(modeset_token);
+
+        state.fake_vblank();
+
+        let state = state.commit_hw_done(modeset_token, plane_update_token);
+
+        state.wait_for_flip_done();
+
+        state
+    }
+}
+
+pub(crate) struct RvkmsDriver;
+
+const MODE_CONFIG_INFO: ModeConfigInfo = ModeConfigInfo {
+    min_resolution: MIN_RES,
+    max_resolution: MAX_RES,
+    max_cursor: (512, 512),
+    preferred_depth: 0,
+};
+
+pub(crate) struct RvkmsModule {
+    dev: faux::Registration,
+    drm: drv::Registration<RvkmsDriver>,
+}
+
+impl kernel::Module for RvkmsModule {
+    fn init(name: &'static CStr, module: &'static ThisModule) -> Result<Self> {
+        pr_info!("RVKMS Loaded\n");
+
+        let dev = faux::Registration::new(NAME)?;
+        dev_info!(dev.as_ref(), "Setting up DRM\n");
+
+        let drm = drv::Registration::<RvkmsDriver>::new(dev.as_ref(), (), 0)?;
+
+        Ok(Self { dev, drm })
+    }
+}
+
+module! {
+    type: RvkmsModule,
+    name: "rvkms",
+    author: "Lyude Paul",
+    description: "Rust VKMS Proof of Concept driver",
+    license: "GPL v2",
+}