24 files changed, 372 insertions, 230 deletions

diff --git a/Documentation/filesystems/debugfs.rst b/Documentation/filesystems/debugfs.rst
index 610f718ef8b5..55f807293924 100644
--- a/Documentation/filesystems/debugfs.rst
+++ b/Documentation/filesystems/debugfs.rst
@@ -229,22 +229,15 @@ module is unloaded without explicitly removing debugfs entries, the result
 will be a lot of stale pointers and no end of highly antisocial behavior.
 So all debugfs users - at least those which can be built as modules - must
 be prepared to remove all files and directories they create there.  A file
-can be removed with::
+or directory can be removed with::
 
     void debugfs_remove(struct dentry *dentry);
 
 The dentry value can be NULL or an error value, in which case nothing will
-be removed.
-
-Once upon a time, debugfs users were required to remember the dentry
-pointer for every debugfs file they created so that all files could be
-cleaned up.  We live in more civilized times now, though, and debugfs users
-can call::
-
-    void debugfs_remove_recursive(struct dentry *dentry);
-
-If this function is passed a pointer for the dentry corresponding to the
-top-level directory, the entire hierarchy below that directory will be
-removed.
+be removed.  Note that this function will recursively remove all files and
+directories underneath it.  Previously, debugfs_remove_recursive() was used
+to perform that task, but this function is now just an alias to
+debugfs_remove().  debugfs_remove_recursive() should be considered
+deprecated.
 
 .. [1] http://lwn.net/Articles/309298/
diff --git a/Documentation/process/debugging/driver_development_debugging_guide.rst b/Documentation/process/debugging/driver_development_debugging_guide.rst
index 46becda8764b..aca08f457793 100644
--- a/Documentation/process/debugging/driver_development_debugging_guide.rst
+++ b/Documentation/process/debugging/driver_development_debugging_guide.rst
@@ -155,7 +155,7 @@ The general idea is:
     ``my_variable``
 
 - Clean up the directory when removing the device
-  (``debugfs_remove_recursive(parent);``)
+  (``debugfs_remove(parent);``)
 
 For the full documentation see :doc:`/filesystems/debugfs`.
 
diff --git a/drivers/base/auxiliary.c b/drivers/base/auxiliary.c
index 95717d509ca9..dba7c8e13a53 100644
--- a/drivers/base/auxiliary.c
+++ b/drivers/base/auxiliary.c
@@ -395,6 +395,114 @@ void auxiliary_driver_unregister(struct auxiliary_driver *auxdrv)
 }
 EXPORT_SYMBOL_GPL(auxiliary_driver_unregister);
 
+static void auxiliary_device_release(struct device *dev)
+{
+	struct auxiliary_device *auxdev = to_auxiliary_dev(dev);
+
+	kfree(auxdev);
+}
+
+/**
+ * auxiliary_device_create - create a device on the auxiliary bus
+ * @dev: parent device
+ * @modname: module name used to create the auxiliary driver name.
+ * @devname: auxiliary bus device name
+ * @platform_data: auxiliary bus device platform data
+ * @id: auxiliary bus device id
+ *
+ * Helper to create an auxiliary bus device.
+ * The device created matches driver 'modname.devname' on the auxiliary bus.
+ */
+struct auxiliary_device *auxiliary_device_create(struct device *dev,
+						 const char *modname,
+						 const char *devname,
+						 void *platform_data,
+						 int id)
+{
+	struct auxiliary_device *auxdev;
+	int ret;
+
+	auxdev = kzalloc(sizeof(*auxdev), GFP_KERNEL);
+	if (!auxdev)
+		return NULL;
+
+	auxdev->id = id;
+	auxdev->name = devname;
+	auxdev->dev.parent = dev;
+	auxdev->dev.platform_data = platform_data;
+	auxdev->dev.release = auxiliary_device_release;
+	device_set_of_node_from_dev(&auxdev->dev, dev);
+
+	ret = auxiliary_device_init(auxdev);
+	if (ret) {
+		kfree(auxdev);
+		return NULL;
+	}
+
+	ret = __auxiliary_device_add(auxdev, modname);
+	if (ret) {
+		/*
+		 * It may look odd but auxdev should not be freed here.
+		 * auxiliary_device_uninit() calls device_put() which call
+		 * the device release function, freeing auxdev.
+		 */
+		auxiliary_device_uninit(auxdev);
+		return NULL;
+	}
+
+	return auxdev;
+}
+EXPORT_SYMBOL_GPL(auxiliary_device_create);
+
+/**
+ * auxiliary_device_destroy - remove an auxiliary device
+ * @auxdev: pointer to the auxdev to be removed
+ *
+ * Helper to remove an auxiliary device created with
+ * auxiliary_device_create()
+ */
+void auxiliary_device_destroy(void *auxdev)
+{
+	struct auxiliary_device *_auxdev = auxdev;
+
+	auxiliary_device_delete(_auxdev);
+	auxiliary_device_uninit(_auxdev);
+}
+EXPORT_SYMBOL_GPL(auxiliary_device_destroy);
+
+/**
+ * __devm_auxiliary_device_create - create a managed device on the auxiliary bus
+ * @dev: parent device
+ * @modname: module name used to create the auxiliary driver name.
+ * @devname: auxiliary bus device name
+ * @platform_data: auxiliary bus device platform data
+ * @id: auxiliary bus device id
+ *
+ * Device managed helper to create an auxiliary bus device.
+ * The device created matches driver 'modname.devname' on the auxiliary bus.
+ */
+struct auxiliary_device *__devm_auxiliary_device_create(struct device *dev,
+							const char *modname,
+							const char *devname,
+							void *platform_data,
+							int id)
+{
+	struct auxiliary_device *auxdev;
+	int ret;
+
+	auxdev = auxiliary_device_create(dev, modname, devname, platform_data, id);
+	if (!auxdev)
+		return NULL;
+
+	ret = devm_add_action_or_reset(dev, auxiliary_device_destroy,
+				       auxdev);
+	if (ret)
+		return NULL;
+
+	return auxdev;
+}
+EXPORT_SYMBOL_GPL(__devm_auxiliary_device_create);
+
 void __init auxiliary_bus_init(void)
 {
 	WARN_ON(bus_register(&auxiliary_bus_type));
diff --git a/drivers/base/component.c b/drivers/base/component.c
index abe60eb45c55..024ad9471b8a 100644
--- a/drivers/base/component.c
+++ b/drivers/base/component.c
@@ -586,7 +586,8 @@ EXPORT_SYMBOL_GPL(component_master_is_bound);
 static void component_unbind(struct component *component,
 	struct aggregate_device *adev, void *data)
 {
-	WARN_ON(!component->bound);
+	if (WARN_ON(!component->bound))
+		return;
 
 	dev_dbg(adev->parent, "unbinding %s component %p (ops %ps)\n",
 		dev_name(component->dev), component, component->ops);
diff --git a/drivers/base/devres.c b/drivers/base/devres.c
index d8a733ea5e1a..ff55e1bcfa30 100644
--- a/drivers/base/devres.c
+++ b/drivers/base/devres.c
@@ -759,6 +759,17 @@ int __devm_add_action(struct device *dev, void (*action)(void *), void *data, co
 }
 EXPORT_SYMBOL_GPL(__devm_add_action);
 
+bool devm_is_action_added(struct device *dev, void (*action)(void *), void *data)
+{
+	struct action_devres devres = {
+		.data = data,
+		.action = action,
+	};
+
+	return devres_find(dev, devm_action_release, devm_action_match, &devres);
+}
+EXPORT_SYMBOL_GPL(devm_is_action_added);
+
 /**
  * devm_remove_action_nowarn() - removes previously added custom action
  * @dev: Device that owns the action
@@ -976,17 +987,10 @@ EXPORT_SYMBOL_GPL(devm_krealloc);
  */
 char *devm_kstrdup(struct device *dev, const char *s, gfp_t gfp)
 {
-	size_t size;
-	char *buf;
-
 	if (!s)
 		return NULL;
 
-	size = strlen(s) + 1;
-	buf = devm_kmalloc(dev, size, gfp);
-	if (buf)
-		memcpy(buf, s, size);
-	return buf;
+	return devm_kmemdup(dev, s, strlen(s) + 1, gfp);
 }
 EXPORT_SYMBOL_GPL(devm_kstrdup);
 
diff --git a/drivers/base/faux.c b/drivers/base/faux.c
index 407c1d1aad50..9054d346bd7f 100644
--- a/drivers/base/faux.c
+++ b/drivers/base/faux.c
@@ -25,6 +25,7 @@
 struct faux_object {
 	struct faux_device faux_dev;
 	const struct faux_device_ops *faux_ops;
+	const struct attribute_group **groups;
 };
 #define to_faux_object(dev) container_of_const(dev, struct faux_object, faux_dev.dev)
 
@@ -43,10 +44,21 @@ 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;
+	int ret;
 
-	if (faux_ops && faux_ops->probe)
+	if (faux_ops && faux_ops->probe) {
 		ret = faux_ops->probe(faux_dev);
+		if (ret)
+			return ret;
+	}
+
+	/*
+	 * Add groups after the probe succeeds to ensure resources are
+	 * initialized correctly
+	 */
+	ret = device_add_groups(dev, faux_obj->groups);
+	if (ret && faux_ops && faux_ops->remove)
+		faux_ops->remove(faux_dev);
 
 	return ret;
 }
@@ -57,6 +69,8 @@ static void faux_remove(struct device *dev)
 	struct faux_device *faux_dev = &faux_obj->faux_dev;
 	const struct faux_device_ops *faux_ops = faux_obj->faux_ops;
 
+	device_remove_groups(dev, faux_obj->groups);
+
 	if (faux_ops && faux_ops->remove)
 		faux_ops->remove(faux_dev);
 }
@@ -124,8 +138,9 @@ struct faux_device *faux_device_create_with_groups(const char *name,
 	if (!faux_obj)
 		return NULL;
 
-	/* Save off the callbacks so we can use them in the future */
+	/* Save off the callbacks and groups so we can use them in the future */
 	faux_obj->faux_ops = faux_ops;
+	faux_obj->groups = groups;
 
 	/* Initialize the device portion and register it with the driver core */
 	faux_dev = &faux_obj->faux_dev;
@@ -138,7 +153,6 @@ struct faux_device *faux_device_create_with_groups(const char *name,
 	else
 		dev->parent = &faux_bus_root;
 	dev->bus = &faux_bus_type;
-	dev->groups = groups;
 	dev_set_name(dev, "%s", name);
 
 	ret = device_add(dev);
diff --git a/drivers/base/firmware_loader/Kconfig b/drivers/base/firmware_loader/Kconfig
index a03701674265..752b9a9bea03 100644
--- a/drivers/base/firmware_loader/Kconfig
+++ b/drivers/base/firmware_loader/Kconfig
@@ -3,8 +3,7 @@ menu "Firmware loader"
 
 config FW_LOADER
 	tristate "Firmware loading facility" if EXPERT
-	select CRYPTO_HASH if FW_LOADER_DEBUG
-	select CRYPTO_SHA256 if FW_LOADER_DEBUG
+	select CRYPTO_LIB_SHA256 if FW_LOADER_DEBUG
 	default y
 	help
 	  This enables the firmware loading facility in the kernel. The kernel
@@ -28,7 +27,6 @@ config FW_LOADER
 
 config FW_LOADER_DEBUG
 	bool "Log filenames and checksums for loaded firmware"
-	depends on CRYPTO = FW_LOADER || CRYPTO=y
 	depends on DYNAMIC_DEBUG
 	depends on FW_LOADER
 	default FW_LOADER
diff --git a/drivers/base/firmware_loader/main.c b/drivers/base/firmware_loader/main.c
index cb0912ea3e62..44486b2c7172 100644
--- a/drivers/base/firmware_loader/main.c
+++ b/drivers/base/firmware_loader/main.c
@@ -806,41 +806,15 @@ static void fw_abort_batch_reqs(struct firmware *fw)
 }
 
 #if defined(CONFIG_FW_LOADER_DEBUG)
-#include <crypto/hash.h>
 #include <crypto/sha2.h>
 
 static void fw_log_firmware_info(const struct firmware *fw, const char *name, struct device *device)
 {
-	struct shash_desc *shash;
-	struct crypto_shash *alg;
-	u8 *sha256buf;
-	char *outbuf;
+	u8 digest[SHA256_DIGEST_SIZE];
 
-	alg = crypto_alloc_shash("sha256", 0, 0);
-	if (IS_ERR(alg))
-		return;
-
-	sha256buf = kmalloc(SHA256_DIGEST_SIZE, GFP_KERNEL);
-	outbuf = kmalloc(SHA256_BLOCK_SIZE + 1, GFP_KERNEL);
-	shash = kmalloc(sizeof(*shash) + crypto_shash_descsize(alg), GFP_KERNEL);
-	if (!sha256buf || !outbuf || !shash)
-		goto out_free;
-
-	shash->tfm = alg;
-
-	if (crypto_shash_digest(shash, fw->data, fw->size, sha256buf) < 0)
-		goto out_free;
-
-	for (int i = 0; i < SHA256_DIGEST_SIZE; i++)
-		sprintf(&outbuf[i * 2], "%02x", sha256buf[i]);
-	outbuf[SHA256_BLOCK_SIZE] = 0;
-	dev_dbg(device, "Loaded FW: %s, sha256: %s\n", name, outbuf);
-
-out_free:
-	kfree(shash);
-	kfree(outbuf);
-	kfree(sha256buf);
-	crypto_free_shash(alg);
+	sha256(fw->data, fw->size, digest);
+	dev_dbg(device, "Loaded FW: %s, sha256: %*phN\n",
+		name, SHA256_DIGEST_SIZE, digest);
 }
 #else
 static void fw_log_firmware_info(const struct firmware *fw, const char *name,
diff --git a/drivers/base/platform.c b/drivers/base/platform.c
index cfccf3ff36e7..075ec1d1b73a 100644
--- a/drivers/base/platform.c
+++ b/drivers/base/platform.c
@@ -982,7 +982,7 @@ struct platform_device * __init_or_module __platform_create_bundle(
 	struct platform_device *pdev;
 	int error;
 
-	pdev = platform_device_alloc(driver->driver.name, -1);
+	pdev = platform_device_alloc(driver->driver.name, PLATFORM_DEVID_NONE);
 	if (!pdev) {
 		error = -ENOMEM;
 		goto err_out;
diff --git a/drivers/base/power/wakeup.c b/drivers/base/power/wakeup.c
index 63bf914a4d44..27505dea7c1b 100644
--- a/drivers/base/power/wakeup.c
+++ b/drivers/base/power/wakeup.c
@@ -77,7 +77,7 @@ static DEFINE_IDA(wakeup_ida);
  * wakeup_source_create - Create a struct wakeup_source object.
  * @name: Name of the new wakeup source.
  */
-struct wakeup_source *wakeup_source_create(const char *name)
+static struct wakeup_source *wakeup_source_create(const char *name)
 {
 	struct wakeup_source *ws;
 	const char *ws_name;
@@ -106,7 +106,6 @@ err_name:
 err_ws:
 	return NULL;
 }
-EXPORT_SYMBOL_GPL(wakeup_source_create);
 
 /*
  * Record wakeup_source statistics being deleted into a dummy wakeup_source.
@@ -149,7 +148,7 @@ static void wakeup_source_free(struct wakeup_source *ws)
  *
  * Use only for wakeup source objects created with wakeup_source_create().
  */
-void wakeup_source_destroy(struct wakeup_source *ws)
+static void wakeup_source_destroy(struct wakeup_source *ws)
 {
 	if (!ws)
 		return;
@@ -158,13 +157,12 @@ void wakeup_source_destroy(struct wakeup_source *ws)
 	wakeup_source_record(ws);
 	wakeup_source_free(ws);
 }
-EXPORT_SYMBOL_GPL(wakeup_source_destroy);
 
 /**
  * wakeup_source_add - Add given object to the list of wakeup sources.
  * @ws: Wakeup source object to add to the list.
  */
-void wakeup_source_add(struct wakeup_source *ws)
+static void wakeup_source_add(struct wakeup_source *ws)
 {
 	unsigned long flags;
 
@@ -179,13 +177,12 @@ void wakeup_source_add(struct wakeup_source *ws)
 	list_add_rcu(&ws->entry, &wakeup_sources);
 	raw_spin_unlock_irqrestore(&events_lock, flags);
 }
-EXPORT_SYMBOL_GPL(wakeup_source_add);
 
 /**
  * wakeup_source_remove - Remove given object from the wakeup sources list.
  * @ws: Wakeup source object to remove from the list.
  */
-void wakeup_source_remove(struct wakeup_source *ws)
+static void wakeup_source_remove(struct wakeup_source *ws)
 {
 	unsigned long flags;
 
@@ -204,7 +201,6 @@ void wakeup_source_remove(struct wakeup_source *ws)
 	 */
 	ws->timer.function = NULL;
 }
-EXPORT_SYMBOL_GPL(wakeup_source_remove);
 
 /**
  * wakeup_source_register - Create wakeup source and add it to the list.
diff --git a/drivers/base/swnode.c b/drivers/base/swnode.c
index 5c78fa6ae772..deda7f35a059 100644
--- a/drivers/base/swnode.c
+++ b/drivers/base/swnode.c
@@ -529,7 +529,7 @@ software_node_get_reference_args(const struct fwnode_handle *fwnode,
 	if (prop->is_inline)
 		return -EINVAL;
 
-	if (index * sizeof(*ref) >= prop->length)
+	if ((index + 1) * sizeof(*ref) > prop->length)
 		return -ENOENT;
 
 	ref_array = prop->pointer;
diff --git a/fs/kernfs/dir.c b/fs/kernfs/dir.c
index fc70d72c3fe8..d63a96786c9b 100644
--- a/fs/kernfs/dir.c
+++ b/fs/kernfs/dir.c
@@ -17,7 +17,6 @@
 
 #include "kernfs-internal.h"
 
-DEFINE_RWLOCK(kernfs_rename_lock);	/* kn->parent and ->name */
 /*
  * Don't use rename_lock to piggy back on pr_cont_buf. We don't want to
  * call pr_cont() while holding rename_lock. Because sometimes pr_cont()
@@ -27,7 +26,6 @@ DEFINE_RWLOCK(kernfs_rename_lock);	/* kn->parent and ->name */
  */
 static DEFINE_SPINLOCK(kernfs_pr_cont_lock);
 static char kernfs_pr_cont_buf[PATH_MAX];	/* protected by pr_cont_lock */
-static DEFINE_SPINLOCK(kernfs_idr_lock);	/* root->ino_idr */
 
 #define rb_to_kn(X) rb_entry((X), struct kernfs_node, rb)
 
@@ -229,7 +227,7 @@ int kernfs_path_from_node(struct kernfs_node *to, struct kernfs_node *from,
 	if (to) {
 		root = kernfs_root(to);
 		if (!(root->flags & KERNFS_ROOT_INVARIANT_PARENT)) {
-			guard(read_lock_irqsave)(&kernfs_rename_lock);
+			guard(read_lock_irqsave)(&root->kernfs_rename_lock);
 			return kernfs_path_from_node_locked(to, from, buf, buflen);
 		}
 	}
@@ -296,12 +294,14 @@ out:
 struct kernfs_node *kernfs_get_parent(struct kernfs_node *kn)
 {
 	struct kernfs_node *parent;
+	struct kernfs_root *root;
 	unsigned long flags;
 
-	read_lock_irqsave(&kernfs_rename_lock, flags);
+	root = kernfs_root(kn);
+	read_lock_irqsave(&root->kernfs_rename_lock, flags);
 	parent = kernfs_parent(kn);
 	kernfs_get(parent);
-	read_unlock_irqrestore(&kernfs_rename_lock, flags);
+	read_unlock_irqrestore(&root->kernfs_rename_lock, flags);
 
 	return parent;
 }
@@ -584,9 +584,9 @@ void kernfs_put(struct kernfs_node *kn)
 	if (kernfs_type(kn) == KERNFS_LINK)
 		kernfs_put(kn->symlink.target_kn);
 
-	spin_lock(&kernfs_idr_lock);
+	spin_lock(&root->kernfs_idr_lock);
 	idr_remove(&root->ino_idr, (u32)kernfs_ino(kn));
-	spin_unlock(&kernfs_idr_lock);
+	spin_unlock(&root->kernfs_idr_lock);
 
 	call_rcu(&kn->rcu, kernfs_free_rcu);
 
@@ -639,13 +639,13 @@ static struct kernfs_node *__kernfs_new_node(struct kernfs_root *root,
 		goto err_out1;
 
 	idr_preload(GFP_KERNEL);
-	spin_lock(&kernfs_idr_lock);
+	spin_lock(&root->kernfs_idr_lock);
 	ret = idr_alloc_cyclic(&root->ino_idr, kn, 1, 0, GFP_ATOMIC);
 	if (ret >= 0 && ret < root->last_id_lowbits)
 		root->id_highbits++;
 	id_highbits = root->id_highbits;
 	root->last_id_lowbits = ret;
-	spin_unlock(&kernfs_idr_lock);
+	spin_unlock(&root->kernfs_idr_lock);
 	idr_preload_end();
 	if (ret < 0)
 		goto err_out2;
@@ -681,9 +681,9 @@ static struct kernfs_node *__kernfs_new_node(struct kernfs_root *root,
 	return kn;
 
  err_out3:
-	spin_lock(&kernfs_idr_lock);
+	spin_lock(&root->kernfs_idr_lock);
 	idr_remove(&root->ino_idr, (u32)kernfs_ino(kn));
-	spin_unlock(&kernfs_idr_lock);
+	spin_unlock(&root->kernfs_idr_lock);
  err_out2:
 	kmem_cache_free(kernfs_node_cache, kn);
  err_out1:
@@ -989,10 +989,12 @@ struct kernfs_root *kernfs_create_root(struct kernfs_syscall_ops *scops,
 		return ERR_PTR(-ENOMEM);
 
 	idr_init(&root->ino_idr);
+	spin_lock_init(&root->kernfs_idr_lock);
 	init_rwsem(&root->kernfs_rwsem);
 	init_rwsem(&root->kernfs_iattr_rwsem);
 	init_rwsem(&root->kernfs_supers_rwsem);
 	INIT_LIST_HEAD(&root->supers);
+	rwlock_init(&root->kernfs_rename_lock);
 
 	/*
 	 * On 64bit ino setups, id is ino.  On 32bit, low 32bits are ino.
@@ -1789,7 +1791,7 @@ int kernfs_rename_ns(struct kernfs_node *kn, struct kernfs_node *new_parent,
 	/* rename_lock protects ->parent accessors */
 	if (old_parent != new_parent) {
 		kernfs_get(new_parent);
-		write_lock_irq(&kernfs_rename_lock);
+		write_lock_irq(&root->kernfs_rename_lock);
 
 		rcu_assign_pointer(kn->__parent, new_parent);
 
@@ -1797,7 +1799,7 @@ int kernfs_rename_ns(struct kernfs_node *kn, struct kernfs_node *new_parent,
 		if (new_name)
 			rcu_assign_pointer(kn->name, new_name);
 
-		write_unlock_irq(&kernfs_rename_lock);
+		write_unlock_irq(&root->kernfs_rename_lock);
 		kernfs_put(old_parent);
 	} else {
 		/* name assignment is RCU protected, parent is the same */
diff --git a/fs/kernfs/kernfs-internal.h b/fs/kernfs/kernfs-internal.h
index 40a2a9cd819d..6061b6f70d2a 100644
--- a/fs/kernfs/kernfs-internal.h
+++ b/fs/kernfs/kernfs-internal.h
@@ -19,8 +19,6 @@
 #include <linux/kernfs.h>
 #include <linux/fs_context.h>
 
-extern rwlock_t kernfs_rename_lock;
-
 struct kernfs_iattrs {
 	kuid_t			ia_uid;
 	kgid_t			ia_gid;
@@ -40,6 +38,7 @@ struct kernfs_root {
 
 	/* private fields, do not use outside kernfs proper */
 	struct idr		ino_idr;
+	spinlock_t		kernfs_idr_lock;	/* root->ino_idr */
 	u32			last_id_lowbits;
 	u32			id_highbits;
 	struct kernfs_syscall_ops *syscall_ops;
@@ -52,6 +51,9 @@ struct kernfs_root {
 	struct rw_semaphore	kernfs_iattr_rwsem;
 	struct rw_semaphore	kernfs_supers_rwsem;
 
+	/* kn->parent and kn->name */
+	rwlock_t		kernfs_rename_lock;
+
 	struct rcu_head		rcu;
 };
 
@@ -107,6 +109,11 @@ static inline bool kernfs_root_is_locked(const struct kernfs_node *kn)
 	return lockdep_is_held(&kernfs_root(kn)->kernfs_rwsem);
 }
 
+static inline bool kernfs_rename_is_locked(const struct kernfs_node *kn)
+{
+	return lockdep_is_held(&kernfs_root(kn)->kernfs_rename_lock);
+}
+
 static inline const char *kernfs_rcu_name(const struct kernfs_node *kn)
 {
 	return rcu_dereference_check(kn->name, kernfs_root_is_locked(kn));
@@ -117,14 +124,15 @@ static inline struct kernfs_node *kernfs_parent(const struct kernfs_node *kn)
 	/*
 	 * The kernfs_node::__parent remains valid within a RCU section. The kn
 	 * can be reparented (and renamed) which changes the entry. This can be
-	 * avoided by locking kernfs_root::kernfs_rwsem or kernfs_rename_lock.
+	 * avoided by locking kernfs_root::kernfs_rwsem or
+	 * kernfs_root::kernfs_rename_lock.
 	 * Both locks can be used to obtain a reference on __parent. Once the
 	 * reference count reaches 0 then the node is about to be freed
 	 * and can not be renamed (or become a different parent) anymore.
 	 */
 	return rcu_dereference_check(kn->__parent,
 				     kernfs_root_is_locked(kn) ||
-				     lockdep_is_held(&kernfs_rename_lock) ||
+				     kernfs_rename_is_locked(kn) ||
 				     !atomic_read(&kn->count));
 }
 
diff --git a/fs/sysfs/group.c b/fs/sysfs/group.c
index 8b01a7eda5fb..2d78e94072a0 100644
--- a/fs/sysfs/group.c
+++ b/fs/sysfs/group.c
@@ -21,7 +21,7 @@ static void remove_files(struct kernfs_node *parent,
 			 const struct attribute_group *grp)
 {
 	struct attribute *const *attr;
-	struct bin_attribute *const *bin_attr;
+	const struct bin_attribute *const *bin_attr;
 
 	if (grp->attrs)
 		for (attr = grp->attrs; *attr; attr++)
@@ -47,7 +47,7 @@ static int create_files(struct kernfs_node *parent, struct kobject *kobj,
 			const struct attribute_group *grp, int update)
 {
 	struct attribute *const *attr;
-	struct bin_attribute *const *bin_attr;
+	const struct bin_attribute *const *bin_attr;
 	int error = 0, i;
 
 	if (grp->attrs) {
@@ -521,7 +521,7 @@ static int sysfs_group_attrs_change_owner(struct kernfs_node *grp_kn,
 	}
 
 	if (grp->bin_attrs) {
-		struct bin_attribute *const *bin_attr;
+		const struct bin_attribute *const *bin_attr;
 
 		for (bin_attr = grp->bin_attrs; *bin_attr; bin_attr++) {
 			kn = kernfs_find_and_get(grp_kn, (*bin_attr)->attr.name);
diff --git a/include/linux/auxiliary_bus.h b/include/linux/auxiliary_bus.h
index 65dd7f154374..4086afd0cc6b 100644
--- a/include/linux/auxiliary_bus.h
+++ b/include/linux/auxiliary_bus.h
@@ -254,6 +254,23 @@ int __auxiliary_driver_register(struct auxiliary_driver *auxdrv, struct module *
 
 void auxiliary_driver_unregister(struct auxiliary_driver *auxdrv);
 
+struct auxiliary_device *auxiliary_device_create(struct device *dev,
+						 const char *modname,
+						 const char *devname,
+						 void *platform_data,
+						 int id);
+void auxiliary_device_destroy(void *auxdev);
+
+struct auxiliary_device *__devm_auxiliary_device_create(struct device *dev,
+							const char *modname,
+							const char *devname,
+							void *platform_data,
+							int id);
+
+#define devm_auxiliary_device_create(dev, devname, platform_data)     \
+	__devm_auxiliary_device_create(dev, KBUILD_MODNAME, devname,  \
+				       platform_data, 0)
+
 /**
  * module_auxiliary_driver() - Helper macro for registering an auxiliary driver
  * @__auxiliary_driver: auxiliary driver struct
diff --git a/include/linux/device.h b/include/linux/device.h
index 79e49fe494b7..4940db137fff 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -281,44 +281,6 @@ int __must_check device_create_bin_file(struct device *dev,
 void device_remove_bin_file(struct device *dev,
 			    const struct bin_attribute *attr);
 
-/* allows to add/remove a custom action to devres stack */
-int devm_remove_action_nowarn(struct device *dev, void (*action)(void *), void *data);
-
-/**
- * devm_remove_action() - removes previously added custom action
- * @dev: Device that owns the action
- * @action: Function implementing the action
- * @data: Pointer to data passed to @action implementation
- *
- * Removes instance of @action previously added by devm_add_action().
- * Both action and data should match one of the existing entries.
- */
-static inline
-void devm_remove_action(struct device *dev, void (*action)(void *), void *data)
-{
-	WARN_ON(devm_remove_action_nowarn(dev, action, data));
-}
-
-void devm_release_action(struct device *dev, void (*action)(void *), void *data);
-
-int __devm_add_action(struct device *dev, void (*action)(void *), void *data, const char *name);
-#define devm_add_action(dev, action, data) \
-	__devm_add_action(dev, action, data, #action)
-
-static inline int __devm_add_action_or_reset(struct device *dev, void (*action)(void *),
-					     void *data, const char *name)
-{
-	int ret;
-
-	ret = __devm_add_action(dev, action, data, name);
-	if (ret)
-		action(data);
-
-	return ret;
-}
-#define devm_add_action_or_reset(dev, action, data) \
-	__devm_add_action_or_reset(dev, action, data, #action)
-
 /**
  * devm_alloc_percpu - Resource-managed alloc_percpu
  * @dev: Device to allocate per-cpu memory for
diff --git a/include/linux/device/devres.h b/include/linux/device/devres.h
index 9b49f9915850..ae696d10faff 100644
--- a/include/linux/device/devres.h
+++ b/include/linux/device/devres.h
@@ -8,6 +8,7 @@
 #include <linux/overflow.h>
 #include <linux/stdarg.h>
 #include <linux/types.h>
+#include <asm/bug.h>
 
 struct device;
 struct device_node;
@@ -126,4 +127,44 @@ void __iomem *devm_of_iomap(struct device *dev, struct device_node *node, int in
 
 #endif
 
+/* allows to add/remove a custom action to devres stack */
+int devm_remove_action_nowarn(struct device *dev, void (*action)(void *), void *data);
+
+/**
+ * devm_remove_action() - removes previously added custom action
+ * @dev: Device that owns the action
+ * @action: Function implementing the action
+ * @data: Pointer to data passed to @action implementation
+ *
+ * Removes instance of @action previously added by devm_add_action().
+ * Both action and data should match one of the existing entries.
+ */
+static inline
+void devm_remove_action(struct device *dev, void (*action)(void *), void *data)
+{
+	WARN_ON(devm_remove_action_nowarn(dev, action, data));
+}
+
+void devm_release_action(struct device *dev, void (*action)(void *), void *data);
+
+int __devm_add_action(struct device *dev, void (*action)(void *), void *data, const char *name);
+#define devm_add_action(dev, action, data) \
+	__devm_add_action(dev, action, data, #action)
+
+static inline int __devm_add_action_or_reset(struct device *dev, void (*action)(void *),
+					     void *data, const char *name)
+{
+	int ret;
+
+	ret = __devm_add_action(dev, action, data, name);
+	if (ret)
+		action(data);
+
+	return ret;
+}
+#define devm_add_action_or_reset(dev, action, data) \
+	__devm_add_action_or_reset(dev, action, data, #action)
+
+bool devm_is_action_added(struct device *dev, void (*action)(void *), void *data);
+
 #endif /* _DEVICE_DEVRES_H_ */
diff --git a/include/linux/pm_wakeup.h b/include/linux/pm_wakeup.h
index 51e0e8dd5f9e..c838b4a30f87 100644
--- a/include/linux/pm_wakeup.h
+++ b/include/linux/pm_wakeup.h
@@ -95,10 +95,6 @@ static inline void device_set_wakeup_path(struct device *dev)
 }
 
 /* drivers/base/power/wakeup.c */
-extern struct wakeup_source *wakeup_source_create(const char *name);
-extern void wakeup_source_destroy(struct wakeup_source *ws);
-extern void wakeup_source_add(struct wakeup_source *ws);
-extern void wakeup_source_remove(struct wakeup_source *ws);
 extern struct wakeup_source *wakeup_source_register(struct device *dev,
 						    const char *name);
 extern void wakeup_source_unregister(struct wakeup_source *ws);
@@ -129,17 +125,6 @@ static inline bool device_can_wakeup(struct device *dev)
 	return dev->power.can_wakeup;
 }
 
-static inline struct wakeup_source *wakeup_source_create(const char *name)
-{
-	return NULL;
-}
-
-static inline void wakeup_source_destroy(struct wakeup_source *ws) {}
-
-static inline void wakeup_source_add(struct wakeup_source *ws) {}
-
-static inline void wakeup_source_remove(struct wakeup_source *ws) {}
-
 static inline struct wakeup_source *wakeup_source_register(struct device *dev,
 							   const char *name)
 {
diff --git a/include/linux/sysfs.h b/include/linux/sysfs.h
index 18f7e1fd093c..f418aae4f113 100644
--- a/include/linux/sysfs.h
+++ b/include/linux/sysfs.h
@@ -107,7 +107,7 @@ struct attribute_group {
 					    int);
 	struct attribute	**attrs;
 	union {
-		struct bin_attribute		**bin_attrs;
+		const struct bin_attribute	*const *bin_attrs;
 		const struct bin_attribute	*const *bin_attrs_new;
 	};
 };
@@ -306,11 +306,11 @@ struct bin_attribute {
 	size_t			size;
 	void			*private;
 	struct address_space *(*f_mapping)(void);
-	ssize_t (*read)(struct file *, struct kobject *, struct bin_attribute *,
+	ssize_t (*read)(struct file *, struct kobject *, const struct bin_attribute *,
 			char *, loff_t, size_t);
 	ssize_t (*read_new)(struct file *, struct kobject *, const struct bin_attribute *,
 			    char *, loff_t, size_t);
-	ssize_t (*write)(struct file *, struct kobject *, struct bin_attribute *,
+	ssize_t (*write)(struct file *, struct kobject *, const struct bin_attribute *,
 			 char *, loff_t, size_t);
 	ssize_t (*write_new)(struct file *, struct kobject *,
 			     const struct bin_attribute *, char *, loff_t, size_t);
@@ -332,28 +332,11 @@ struct bin_attribute {
  */
 #define sysfs_bin_attr_init(bin_attr) sysfs_attr_init(&(bin_attr)->attr)
 
-typedef ssize_t __sysfs_bin_rw_handler_new(struct file *, struct kobject *,
-					   const struct bin_attribute *, char *, loff_t, size_t);
-
 /* macros to create static binary attributes easier */
 #define __BIN_ATTR(_name, _mode, _read, _write, _size) {		\
 	.attr = { .name = __stringify(_name), .mode = _mode },		\
-	.read = _Generic(_read,						\
-		__sysfs_bin_rw_handler_new * : NULL,			\
-		default : _read						\
-	),								\
-	.read_new = _Generic(_read,					\
-		__sysfs_bin_rw_handler_new * : _read,			\
-		default : NULL						\
-	),								\
-	.write = _Generic(_write,					\
-		__sysfs_bin_rw_handler_new * : NULL,			\
-		default : _write					\
-	),								\
-	.write_new = _Generic(_write,					\
-		__sysfs_bin_rw_handler_new * : _write,			\
-		default : NULL						\
-	),								\
+	.read = _read,							\
+	.write = _write,						\
 	.size	= _size,						\
 }
 
diff --git a/rust/kernel/device.rs b/rust/kernel/device.rs
index 21b343a1dc4d..0353c5552769 100644
--- a/rust/kernel/device.rs
+++ b/rust/kernel/device.rs
@@ -9,7 +9,7 @@ use crate::{
     str::CStr,
     types::{ARef, Opaque},
 };
-use core::{fmt, ptr};
+use core::{fmt, marker::PhantomData, ptr};
 
 #[cfg(CONFIG_PRINTK)]
 use crate::c_str;
@@ -42,7 +42,7 @@ use crate::c_str;
 /// `bindings::device::release` is valid to be called from any thread, hence `ARef<Device>` can be
 /// dropped from any thread.
 #[repr(transparent)]
-pub struct Device(Opaque<bindings::device>);
+pub struct Device<Ctx: DeviceContext = Normal>(Opaque<bindings::device>, PhantomData<Ctx>);
 
 impl Device {
     /// Creates a new reference-counted abstraction instance of an existing `struct device` pointer.
@@ -59,7 +59,9 @@ impl Device {
         // SAFETY: By the safety requirements ptr is valid
         unsafe { Self::as_ref(ptr) }.into()
     }
+}
 
+impl<Ctx: DeviceContext> Device<Ctx> {
     /// Obtain the raw `struct device *`.
     pub(crate) fn as_raw(&self) -> *mut bindings::device {
         self.0.get()
@@ -189,6 +191,11 @@ impl Device {
     }
 }
 
+// SAFETY: `Device` is a transparent wrapper of a type that doesn't depend on `Device`'s generic
+// argument.
+kernel::impl_device_context_deref!(unsafe { Device });
+kernel::impl_device_context_into_aref!(Device);
+
 // SAFETY: Instances of `Device` are always reference-counted.
 unsafe impl crate::types::AlwaysRefCounted for Device {
     fn inc_ref(&self) {
@@ -225,16 +232,95 @@ pub struct Normal;
 /// any of the bus callbacks, such as `probe()`.
 pub struct Core;
 
+/// The [`Bound`] context is the context of a bus specific device reference when it is guaranteed to
+/// be bound for the duration of its lifetime.
+pub struct Bound;
+
 mod private {
     pub trait Sealed {}
 
+    impl Sealed for super::Bound {}
     impl Sealed for super::Core {}
     impl Sealed for super::Normal {}
 }
 
+impl DeviceContext for Bound {}
 impl DeviceContext for Core {}
 impl DeviceContext for Normal {}
 
+/// # Safety
+///
+/// The type given as `$device` must be a transparent wrapper of a type that doesn't depend on the
+/// generic argument of `$device`.
+#[doc(hidden)]
+#[macro_export]
+macro_rules! __impl_device_context_deref {
+    (unsafe { $device:ident, $src:ty => $dst:ty }) => {
+        impl ::core::ops::Deref for $device<$src> {
+            type Target = $device<$dst>;
+
+            fn deref(&self) -> &Self::Target {
+                let ptr: *const Self = self;
+
+                // CAST: `$device<$src>` and `$device<$dst>` transparently wrap the same type by the
+                // safety requirement of the macro.
+                let ptr = ptr.cast::<Self::Target>();
+
+                // SAFETY: `ptr` was derived from `&self`.
+                unsafe { &*ptr }
+            }
+        }
+    };
+}
+
+/// Implement [`core::ops::Deref`] traits for allowed [`DeviceContext`] conversions of a (bus
+/// specific) device.
+///
+/// # Safety
+///
+/// The type given as `$device` must be a transparent wrapper of a type that doesn't depend on the
+/// generic argument of `$device`.
+#[macro_export]
+macro_rules! impl_device_context_deref {
+    (unsafe { $device:ident }) => {
+        // SAFETY: This macro has the exact same safety requirement as
+        // `__impl_device_context_deref!`.
+        ::kernel::__impl_device_context_deref!(unsafe {
+            $device,
+            $crate::device::Core => $crate::device::Bound
+        });
+
+        // SAFETY: This macro has the exact same safety requirement as
+        // `__impl_device_context_deref!`.
+        ::kernel::__impl_device_context_deref!(unsafe {
+            $device,
+            $crate::device::Bound => $crate::device::Normal
+        });
+    };
+}
+
+#[doc(hidden)]
+#[macro_export]
+macro_rules! __impl_device_context_into_aref {
+    ($src:ty, $device:tt) => {
+        impl ::core::convert::From<&$device<$src>> for $crate::types::ARef<$device> {
+            fn from(dev: &$device<$src>) -> Self {
+                (&**dev).into()
+            }
+        }
+    };
+}
+
+/// Implement [`core::convert::From`], such that all `&Device<Ctx>` can be converted to an
+/// `ARef<Device>`.
+#[macro_export]
+macro_rules! impl_device_context_into_aref {
+    ($device:tt) => {
+        ::kernel::__impl_device_context_into_aref!($crate::device::Core, $device);
+        ::kernel::__impl_device_context_into_aref!($crate::device::Bound, $device);
+    };
+}
+
 #[doc(hidden)]
 #[macro_export]
 macro_rules! dev_printk {
diff --git a/rust/kernel/devres.rs b/rust/kernel/devres.rs
index ddb1ce4a78d9..1e58f5d22044 100644
--- a/rust/kernel/devres.rs
+++ b/rust/kernel/devres.rs
@@ -8,7 +8,7 @@
 use crate::{
     alloc::Flags,
     bindings,
-    device::Device,
+    device::{Bound, Device},
     error::{Error, Result},
     ffi::c_void,
     prelude::*,
@@ -45,7 +45,7 @@ struct DevresInner<T> {
 /// # Example
 ///
 /// ```no_run
-/// # use kernel::{bindings, c_str, device::Device, devres::Devres, io::{Io, IoRaw}};
+/// # use kernel::{bindings, c_str, device::{Bound, Device}, devres::Devres, io::{Io, IoRaw}};
 /// # use core::ops::Deref;
 ///
 /// // See also [`pci::Bar`] for a real example.
@@ -83,13 +83,10 @@ struct DevresInner<T> {
 ///         unsafe { Io::from_raw(&self.0) }
 ///    }
 /// }
-/// # fn no_run() -> Result<(), Error> {
-/// # // SAFETY: Invalid usage; just for the example to get an `ARef<Device>` instance.
-/// # let dev = unsafe { Device::get_device(core::ptr::null_mut()) };
-///
+/// # fn no_run(dev: &Device<Bound>) -> Result<(), Error> {
 /// // SAFETY: Invalid usage for example purposes.
 /// let iomem = unsafe { IoMem::<{ core::mem::size_of::<u32>() }>::new(0xBAAAAAAD)? };
-/// let devres = Devres::new(&dev, iomem, GFP_KERNEL)?;
+/// let devres = Devres::new(dev, iomem, GFP_KERNEL)?;
 ///
 /// let res = devres.try_access().ok_or(ENXIO)?;
 /// res.write8(0x42, 0x0);
@@ -99,7 +96,7 @@ struct DevresInner<T> {
 pub struct Devres<T>(Arc<DevresInner<T>>);
 
 impl<T> DevresInner<T> {
-    fn new(dev: &Device, data: T, flags: Flags) -> Result<Arc<DevresInner<T>>> {
+    fn new(dev: &Device<Bound>, data: T, flags: Flags) -> Result<Arc<DevresInner<T>>> {
         let inner = Arc::pin_init(
             pin_init!( DevresInner {
                 dev: dev.into(),
@@ -171,7 +168,7 @@ impl<T> DevresInner<T> {
 impl<T> Devres<T> {
     /// Creates a new [`Devres`] instance of the given `data`. The `data` encapsulated within the
     /// returned `Devres` instance' `data` will be revoked once the device is detached.
-    pub fn new(dev: &Device, data: T, flags: Flags) -> Result<Self> {
+    pub fn new(dev: &Device<Bound>, data: T, flags: Flags) -> Result<Self> {
         let inner = DevresInner::new(dev, data, flags)?;
 
         Ok(Devres(inner))
@@ -179,7 +176,7 @@ impl<T> Devres<T> {
 
     /// Same as [`Devres::new`], but does not return a `Devres` instance. Instead the given `data`
     /// is owned by devres and will be revoked / dropped, once the device is detached.
-    pub fn new_foreign_owned(dev: &Device, data: T, flags: Flags) -> Result {
+    pub fn new_foreign_owned(dev: &Device<Bound>, data: T, flags: Flags) -> Result {
         let _ = DevresInner::new(dev, data, flags)?;
 
         Ok(())
diff --git a/rust/kernel/dma.rs b/rust/kernel/dma.rs
index 8cdc76043ee7..605e01e35715 100644
--- a/rust/kernel/dma.rs
+++ b/rust/kernel/dma.rs
@@ -6,7 +6,7 @@
 
 use crate::{
     bindings, build_assert,
-    device::Device,
+    device::{Bound, Device},
     error::code::*,
     error::Result,
     transmute::{AsBytes, FromBytes},
@@ -22,10 +22,10 @@ use crate::{
 /// # Examples
 ///
 /// ```
-/// use kernel::device::Device;
+/// # use kernel::device::{Bound, Device};
 /// use kernel::dma::{attrs::*, CoherentAllocation};
 ///
-/// # fn test(dev: &Device) -> Result {
+/// # fn test(dev: &Device<Bound>) -> Result {
 /// let attribs = DMA_ATTR_FORCE_CONTIGUOUS | DMA_ATTR_NO_WARN;
 /// let c: CoherentAllocation<u64> =
 ///     CoherentAllocation::alloc_attrs(dev, 4, GFP_KERNEL, attribs)?;
@@ -143,16 +143,16 @@ impl<T: AsBytes + FromBytes> CoherentAllocation<T> {
     /// # Examples
     ///
     /// ```
-    /// use kernel::device::Device;
+    /// # use kernel::device::{Bound, Device};
     /// use kernel::dma::{attrs::*, CoherentAllocation};
     ///
-    /// # fn test(dev: &Device) -> Result {
+    /// # fn test(dev: &Device<Bound>) -> Result {
     /// let c: CoherentAllocation<u64> =
     ///     CoherentAllocation::alloc_attrs(dev, 4, GFP_KERNEL, DMA_ATTR_NO_WARN)?;
     /// # Ok::<(), Error>(()) }
     /// ```
     pub fn alloc_attrs(
-        dev: &Device,
+        dev: &Device<Bound>,
         count: usize,
         gfp_flags: kernel::alloc::Flags,
         dma_attrs: Attrs,
@@ -194,7 +194,7 @@ impl<T: AsBytes + FromBytes> CoherentAllocation<T> {
     /// Performs the same functionality as [`CoherentAllocation::alloc_attrs`], except the
     /// `dma_attrs` is 0 by default.
     pub fn alloc_coherent(
-        dev: &Device,
+        dev: &Device<Bound>,
         count: usize,
         gfp_flags: kernel::alloc::Flags,
     ) -> Result<CoherentAllocation<T>> {
diff --git a/rust/kernel/pci.rs b/rust/kernel/pci.rs
index c97d6d470b28..3664d35b8e79 100644
--- a/rust/kernel/pci.rs
+++ b/rust/kernel/pci.rs
@@ -360,11 +360,13 @@ impl<const SIZE: usize> Deref for Bar<SIZE> {
     }
 }
 
-impl Device {
+impl<Ctx: device::DeviceContext> Device<Ctx> {
     fn as_raw(&self) -> *mut bindings::pci_dev {
         self.0.get()
     }
+}
 
+impl Device {
     /// Returns the PCI vendor ID.
     pub fn vendor_id(&self) -> u16 {
         // SAFETY: `self.as_raw` is a valid pointer to a `struct pci_dev`.
@@ -388,7 +390,9 @@ impl Device {
         // - by its type invariant `self.as_raw` is always a valid pointer to a `struct pci_dev`.
         Ok(unsafe { bindings::pci_resource_len(self.as_raw(), bar.try_into()?) })
     }
+}
 
+impl Device<device::Bound> {
     /// Mapps an entire PCI-BAR after performing a region-request on it. I/O operation bound checks
     /// can be performed on compile time for offsets (plus the requested type size) < SIZE.
     pub fn iomap_region_sized<const SIZE: usize>(
@@ -422,25 +426,10 @@ impl Device<device::Core> {
     }
 }
 
-impl Deref for Device<device::Core> {
-    type Target = Device;
-
-    fn deref(&self) -> &Self::Target {
-        let ptr: *const Self = self;
-
-        // CAST: `Device<Ctx>` is a transparent wrapper of `Opaque<bindings::pci_dev>`.
-        let ptr = ptr.cast::<Device>();
-
-        // SAFETY: `ptr` was derived from `&self`.
-        unsafe { &*ptr }
-    }
-}
-
-impl From<&Device<device::Core>> for ARef<Device> {
-    fn from(dev: &Device<device::Core>) -> Self {
-        (&**dev).into()
-    }
-}
+// SAFETY: `Device` is a transparent wrapper of a type that doesn't depend on `Device`'s generic
+// argument.
+kernel::impl_device_context_deref!(unsafe { Device });
+kernel::impl_device_context_into_aref!(Device);
 
 // SAFETY: Instances of `Device` are always reference-counted.
 unsafe impl crate::types::AlwaysRefCounted for Device {
@@ -455,8 +444,8 @@ unsafe impl crate::types::AlwaysRefCounted for Device {
     }
 }
 
-impl AsRef<device::Device> for Device {
-    fn as_ref(&self) -> &device::Device {
+impl<Ctx: device::DeviceContext> AsRef<device::Device<Ctx>> for Device<Ctx> {
+    fn as_ref(&self) -> &device::Device<Ctx> {
         // SAFETY: By the type invariant of `Self`, `self.as_raw()` is a pointer to a valid
         // `struct pci_dev`.
         let dev = unsafe { addr_of_mut!((*self.as_raw()).dev) };
diff --git a/rust/kernel/platform.rs b/rust/kernel/platform.rs
index 4917cb34e2fe..b1c48cd95cd6 100644
--- a/rust/kernel/platform.rs
+++ b/rust/kernel/platform.rs
@@ -10,13 +10,12 @@ use crate::{
     of,
     prelude::*,
     str::CStr,
-    types::{ARef, ForeignOwnable, Opaque},
+    types::{ForeignOwnable, Opaque},
     ThisModule,
 };
 
 use core::{
     marker::PhantomData,
-    ops::Deref,
     ptr::{addr_of_mut, NonNull},
 };
 
@@ -184,31 +183,16 @@ pub struct Device<Ctx: device::DeviceContext = device::Normal>(
     PhantomData<Ctx>,
 );
 
-impl Device {
+impl<Ctx: device::DeviceContext> Device<Ctx> {
     fn as_raw(&self) -> *mut bindings::platform_device {
         self.0.get()
     }
 }
 
-impl Deref for Device<device::Core> {
-    type Target = Device;
-
-    fn deref(&self) -> &Self::Target {
-        let ptr: *const Self = self;
-
-        // CAST: `Device<Ctx>` is a transparent wrapper of `Opaque<bindings::platform_device>`.
-        let ptr = ptr.cast::<Device>();
-
-        // SAFETY: `ptr` was derived from `&self`.
-        unsafe { &*ptr }
-    }
-}
-
-impl From<&Device<device::Core>> for ARef<Device> {
-    fn from(dev: &Device<device::Core>) -> Self {
-        (&**dev).into()
-    }
-}
+// SAFETY: `Device` is a transparent wrapper of a type that doesn't depend on `Device`'s generic
+// argument.
+kernel::impl_device_context_deref!(unsafe { Device });
+kernel::impl_device_context_into_aref!(Device);
 
 // SAFETY: Instances of `Device` are always reference-counted.
 unsafe impl crate::types::AlwaysRefCounted for Device {
@@ -223,8 +207,8 @@ unsafe impl crate::types::AlwaysRefCounted for Device {
     }
 }
 
-impl AsRef<device::Device> for Device {
-    fn as_ref(&self) -> &device::Device {
+impl<Ctx: device::DeviceContext> AsRef<device::Device<Ctx>> for Device<Ctx> {
+    fn as_ref(&self) -> &device::Device<Ctx> {
         // SAFETY: By the type invariant of `Self`, `self.as_raw()` is a pointer to a valid
         // `struct platform_device`.
         let dev = unsafe { addr_of_mut!((*self.as_raw()).dev) };