Merge tag 'driver-core-6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core updates from Greg KH:
 "Here is the "big" set of driver core and kernfs changes for 6.9-rc1.

  Nothing all that crazy here, just some good updates that include:

   - automatic attribute group hiding from Dan Williams (he fixed up my
     horrible attempt at doing this.)

   - kobject lock contention fixes from Eric Dumazet

   - driver core cleanups from Andy

   - kernfs rcu work from Tejun

   - fw_devlink changes to resolve some reported issues

   - other minor changes, all details in the shortlog

  All of these have been in linux-next for a long time with no reported
  issues"

* tag 'driver-core-6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (28 commits)
  device: core: Log warning for devices pending deferred probe on timeout
  driver: core: Use dev_* instead of pr_* so device metadata is added
  driver: core: Log probe failure as error and with device metadata
  of: property: fw_devlink: Add support for "post-init-providers" property
  driver core: Add FWLINK_FLAG_IGNORE to completely ignore a fwnode link
  driver core: Adds flags param to fwnode_link_add()
  debugfs: fix wait/cancellation handling during remove
  device property: Don't use "proxy" headers
  device property: Move enum dev_dma_attr to fwnode.h
  driver core: Move fw_devlink stuff to where it belongs
  driver core: Drop unneeded 'extern' keyword in fwnode.h
  firmware_loader: Suppress warning on FW_OPT_NO_WARN flag
  sysfs:Addresses documentation in sysfs_merge_group and sysfs_unmerge_group.
  firmware_loader: introduce __free() cleanup hanler
  platform-msi: Remove usage of the deprecated ida_simple_xx() API
  sysfs: Introduce DEFINE_SIMPLE_SYSFS_GROUP_VISIBLE()
  sysfs: Document new "group visible" helpers
  sysfs: Fix crash on empty group attributes array
  sysfs: Introduce a mechanism to hide static attribute_groups
  sysfs: Introduce a mechanism to hide static attribute_groups
  ...

7 files changed, 155 insertions, 31 deletions

diff --git a/include/linux/cpu.h b/include/linux/cpu.h
index ae5a20cf2f9c..272e4e79e15c 100644
--- a/include/linux/cpu.h
+++ b/include/linux/cpu.h
@@ -130,7 +130,7 @@ static inline void cpu_maps_update_done(void)
 static inline int add_cpu(unsigned int cpu) { return 0;}
 
 #endif /* CONFIG_SMP */
-extern struct bus_type cpu_subsys;
+extern const struct bus_type cpu_subsys;
 
 extern int lockdep_is_cpus_held(void);
 
diff --git a/include/linux/firmware.h b/include/linux/firmware.h
index 0311858b46ce..f026f8926d79 100644
--- a/include/linux/firmware.h
+++ b/include/linux/firmware.h
@@ -4,6 +4,7 @@
 
 #include <linux/types.h>
 #include <linux/compiler.h>
+#include <linux/cleanup.h>
 #include <linux/gfp.h>
 
 #define FW_ACTION_NOUEVENT 0
@@ -198,4 +199,6 @@ static inline void firmware_upload_unregister(struct fw_upload *fw_upload)
 
 int firmware_request_cache(struct device *device, const char *name);
 
+DEFINE_FREE(firmware, struct firmware *, release_firmware(_T))
+
 #endif
diff --git a/include/linux/fwnode.h b/include/linux/fwnode.h
index 2a72f55d26eb..0d79070c5a70 100644
--- a/include/linux/fwnode.h
+++ b/include/linux/fwnode.h
@@ -9,10 +9,16 @@
 #ifndef _LINUX_FWNODE_H_
 #define _LINUX_FWNODE_H_
 
-#include <linux/types.h>
-#include <linux/list.h>
 #include <linux/bits.h>
 #include <linux/err.h>
+#include <linux/list.h>
+#include <linux/types.h>
+
+enum dev_dma_attr {
+	DEV_DMA_NOT_SUPPORTED,
+	DEV_DMA_NON_COHERENT,
+	DEV_DMA_COHERENT,
+};
 
 struct fwnode_operations;
 struct device;
@@ -53,8 +59,10 @@ struct fwnode_handle {
  * fwnode link flags
  *
  * CYCLE:	The fwnode link is part of a cycle. Don't defer probe.
+ * IGNORE:	Completely ignore this link, even during cycle detection.
  */
 #define FWLINK_FLAG_CYCLE			BIT(0)
+#define FWLINK_FLAG_IGNORE			BIT(1)
 
 struct fwnode_link {
 	struct fwnode_handle *supplier;
@@ -187,7 +195,6 @@ struct fwnode_operations {
 		if (fwnode_has_op(fwnode, op))				\
 			(fwnode)->ops->op(fwnode, ## __VA_ARGS__);	\
 	} while (false)
-#define get_dev_from_fwnode(fwnode)	get_device((fwnode)->dev)
 
 static inline void fwnode_init(struct fwnode_handle *fwnode,
 			       const struct fwnode_operations *ops)
@@ -209,9 +216,10 @@ static inline void fwnode_dev_initialized(struct fwnode_handle *fwnode,
 		fwnode->flags &= ~FWNODE_FLAG_INITIALIZED;
 }
 
-extern bool fw_devlink_is_strict(void);
-int fwnode_link_add(struct fwnode_handle *con, struct fwnode_handle *sup);
+int fwnode_link_add(struct fwnode_handle *con, struct fwnode_handle *sup,
+		    u8 flags);
 void fwnode_links_purge(struct fwnode_handle *fwnode);
 void fw_devlink_purge_absent_suppliers(struct fwnode_handle *fwnode);
+bool fw_devlink_is_strict(void);
 
 #endif
diff --git a/include/linux/kernfs.h b/include/linux/kernfs.h
index 99aaa050ccb7..87c79d076d6d 100644
--- a/include/linux/kernfs.h
+++ b/include/linux/kernfs.h
@@ -206,23 +206,25 @@ struct kernfs_node {
 
 	const void		*ns;	/* namespace tag */
 	unsigned int		hash;	/* ns + name hash */
+	unsigned short		flags;
+	umode_t			mode;
+
 	union {
 		struct kernfs_elem_dir		dir;
 		struct kernfs_elem_symlink	symlink;
 		struct kernfs_elem_attr		attr;
 	};
 
-	void			*priv;
-
 	/*
 	 * 64bit unique ID.  On 64bit ino setups, id is the ino.  On 32bit,
 	 * the low 32bits are ino and upper generation.
 	 */
 	u64			id;
 
-	unsigned short		flags;
-	umode_t			mode;
+	void			*priv;
 	struct kernfs_iattrs	*iattr;
+
+	struct rcu_head		rcu;
 };
 
 /*
diff --git a/include/linux/kobject.h b/include/linux/kobject.h
index c30affcc43b4..c8219505a79f 100644
--- a/include/linux/kobject.h
+++ b/include/linux/kobject.h
@@ -38,7 +38,7 @@ extern char uevent_helper[];
 #endif
 
 /* counter to tag the uevent, read only except for the kobject core */
-extern u64 uevent_seqnum;
+extern atomic64_t uevent_seqnum;
 
 /*
  * The actions here must match the index to the string array
diff --git a/include/linux/property.h b/include/linux/property.h
index e6516d0b7d52..3a1045eb786c 100644
--- a/include/linux/property.h
+++ b/include/linux/property.h
@@ -11,6 +11,7 @@
 #define _LINUX_PROPERTY_H_
 
 #include <linux/args.h>
+#include <linux/array_size.h>
 #include <linux/bits.h>
 #include <linux/fwnode.h>
 #include <linux/stddef.h>
@@ -27,12 +28,6 @@ enum dev_prop_type {
 	DEV_PROP_REF,
 };
 
-enum dev_dma_attr {
-	DEV_DMA_NOT_SUPPORTED,
-	DEV_DMA_NON_COHERENT,
-	DEV_DMA_COHERENT,
-};
-
 const struct fwnode_handle *__dev_fwnode_const(const struct device *dev);
 struct fwnode_handle *__dev_fwnode(struct device *dev);
 #define dev_fwnode(dev)							\
@@ -156,11 +151,9 @@ struct fwnode_handle *fwnode_get_next_parent(struct fwnode_handle *fwnode);
 	for (parent = fwnode_get_parent(fwnode); parent;	\
 	     parent = fwnode_get_next_parent(parent))
 
-struct device *fwnode_get_next_parent_dev(const struct fwnode_handle *fwnode);
 unsigned int fwnode_count_parents(const struct fwnode_handle *fwn);
 struct fwnode_handle *fwnode_get_nth_parent(struct fwnode_handle *fwn,
 					    unsigned int depth);
-bool fwnode_is_ancestor_of(const struct fwnode_handle *ancestor, const struct fwnode_handle *child);
 struct fwnode_handle *fwnode_get_next_child_node(
 	const struct fwnode_handle *fwnode, struct fwnode_handle *child);
 struct fwnode_handle *fwnode_get_next_available_child_node(
diff --git a/include/linux/sysfs.h b/include/linux/sysfs.h
index b717a70219f6..326341c62385 100644
--- a/include/linux/sysfs.h
+++ b/include/linux/sysfs.h
@@ -61,22 +61,32 @@ do {							\
 /**
  * struct attribute_group - data structure used to declare an attribute group.
  * @name:	Optional: Attribute group name
- *		If specified, the attribute group will be created in
- *		a new subdirectory with this name.
+ *		If specified, the attribute group will be created in a
+ *		new subdirectory with this name. Additionally when a
+ *		group is named, @is_visible and @is_bin_visible may
+ *		return SYSFS_GROUP_INVISIBLE to control visibility of
+ *		the directory itself.
  * @is_visible:	Optional: Function to return permissions associated with an
- *		attribute of the group. Will be called repeatedly for each
- *		non-binary attribute in the group. Only read/write
+ *		attribute of the group. Will be called repeatedly for
+ *		each non-binary attribute in the group. Only read/write
  *		permissions as well as SYSFS_PREALLOC are accepted. Must
- *		return 0 if an attribute is not visible. The returned value
- *		will replace static permissions defined in struct attribute.
+ *		return 0 if an attribute is not visible. The returned
+ *		value will replace static permissions defined in struct
+ *		attribute. Use SYSFS_GROUP_VISIBLE() when assigning this
+ *		callback to specify separate _group_visible() and
+ *		_attr_visible() handlers.
  * @is_bin_visible:
  *		Optional: Function to return permissions associated with a
  *		binary attribute of the group. Will be called repeatedly
  *		for each binary attribute in the group. Only read/write
- *		permissions as well as SYSFS_PREALLOC are accepted. Must
- *		return 0 if a binary attribute is not visible. The returned
- *		value will replace static permissions defined in
- *		struct bin_attribute.
+ *		permissions as well as SYSFS_PREALLOC (and the
+ *		visibility flags for named groups) are accepted. Must
+ *		return 0 if a binary attribute is not visible. The
+ *		returned value will replace static permissions defined
+ *		in struct bin_attribute. If @is_visible is not set, Use
+ *		SYSFS_GROUP_VISIBLE() when assigning this callback to
+ *		specify separate _group_visible() and _attr_visible()
+ *		handlers.
  * @attrs:	Pointer to NULL terminated list of attributes.
  * @bin_attrs:	Pointer to NULL terminated list of binary attributes.
  *		Either attrs or bin_attrs or both must be provided.
@@ -91,13 +101,121 @@ struct attribute_group {
 	struct bin_attribute	**bin_attrs;
 };
 
+#define SYSFS_PREALLOC		010000
+#define SYSFS_GROUP_INVISIBLE	020000
+
+/*
+ * DEFINE_SYSFS_GROUP_VISIBLE(name):
+ *	A helper macro to pair with the assignment of ".is_visible =
+ *	SYSFS_GROUP_VISIBLE(name)", that arranges for the directory
+ *	associated with a named attribute_group to optionally be hidden.
+ *	This allows for static declaration of attribute_groups, and the
+ *	simplification of attribute visibility lifetime that implies,
+ *	without polluting sysfs with empty attribute directories.
+ * Ex.
+ *
+ * static umode_t example_attr_visible(struct kobject *kobj,
+ *                                   struct attribute *attr, int n)
+ * {
+ *       if (example_attr_condition)
+ *               return 0;
+ *       else if (ro_attr_condition)
+ *               return 0444;
+ *       return a->mode;
+ * }
+ *
+ * static bool example_group_visible(struct kobject *kobj)
+ * {
+ *       if (example_group_condition)
+ *               return false;
+ *       return true;
+ * }
+ *
+ * DEFINE_SYSFS_GROUP_VISIBLE(example);
+ *
+ * static struct attribute_group example_group = {
+ *       .name = "example",
+ *       .is_visible = SYSFS_GROUP_VISIBLE(example),
+ *       .attrs = &example_attrs,
+ * };
+ *
+ * Note that it expects <name>_attr_visible and <name>_group_visible to
+ * be defined. For cases where individual attributes do not need
+ * separate visibility consideration, only entire group visibility at
+ * once, see DEFINE_SIMPLE_SYSFS_GROUP_VISIBLE().
+ */
+#define DEFINE_SYSFS_GROUP_VISIBLE(name)                             \
+	static inline umode_t sysfs_group_visible_##name(            \
+		struct kobject *kobj, struct attribute *attr, int n) \
+	{                                                            \
+		if (n == 0 && !name##_group_visible(kobj))           \
+			return SYSFS_GROUP_INVISIBLE;                \
+		return name##_attr_visible(kobj, attr, n);           \
+	}
+
+/*
+ * DEFINE_SIMPLE_SYSFS_GROUP_VISIBLE(name):
+ *	A helper macro to pair with SYSFS_GROUP_VISIBLE() that like
+ *	DEFINE_SYSFS_GROUP_VISIBLE() controls group visibility, but does
+ *	not require the implementation of a per-attribute visibility
+ *	callback.
+ * Ex.
+ *
+ * static bool example_group_visible(struct kobject *kobj)
+ * {
+ *       if (example_group_condition)
+ *               return false;
+ *       return true;
+ * }
+ *
+ * DEFINE_SIMPLE_SYSFS_GROUP_VISIBLE(example);
+ *
+ * static struct attribute_group example_group = {
+ *       .name = "example",
+ *       .is_visible = SYSFS_GROUP_VISIBLE(example),
+ *       .attrs = &example_attrs,
+ * };
+ */
+#define DEFINE_SIMPLE_SYSFS_GROUP_VISIBLE(name)                   \
+	static inline umode_t sysfs_group_visible_##name(         \
+		struct kobject *kobj, struct attribute *a, int n) \
+	{                                                         \
+		if (n == 0 && !name##_group_visible(kobj))        \
+			return SYSFS_GROUP_INVISIBLE;             \
+		return a->mode;                                   \
+	}
+
+/*
+ * Same as DEFINE_SYSFS_GROUP_VISIBLE, but for groups with only binary
+ * attributes. If an attribute_group defines both text and binary
+ * attributes, the group visibility is determined by the function
+ * specified to is_visible() not is_bin_visible()
+ */
+#define DEFINE_SYSFS_BIN_GROUP_VISIBLE(name)                             \
+	static inline umode_t sysfs_group_visible_##name(                \
+		struct kobject *kobj, struct bin_attribute *attr, int n) \
+	{                                                                \
+		if (n == 0 && !name##_group_visible(kobj))               \
+			return SYSFS_GROUP_INVISIBLE;                    \
+		return name##_attr_visible(kobj, attr, n);               \
+	}
+
+#define DEFINE_SIMPLE_SYSFS_BIN_GROUP_VISIBLE(name)                   \
+	static inline umode_t sysfs_group_visible_##name(             \
+		struct kobject *kobj, struct bin_attribute *a, int n) \
+	{                                                             \
+		if (n == 0 && !name##_group_visible(kobj))            \
+			return SYSFS_GROUP_INVISIBLE;                 \
+		return a->mode;                                       \
+	}
+
+#define SYSFS_GROUP_VISIBLE(fn) sysfs_group_visible_##fn
+
 /*
  * Use these macros to make defining attributes easier.
  * See include/linux/device.h for examples..
  */
 
-#define SYSFS_PREALLOC 010000
-
 #define __ATTR(_name, _mode, _show, _store) {				\
 	.attr = {.name = __stringify(_name),				\
 		 .mode = VERIFY_OCTAL_PERMISSIONS(_mode) },		\