Merge tag 'driver-core-6.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core updates from Greg KH:
 "Here is the small set of driver core and kernfs changes for 6.10-rc1.

  Nothing major here at all, just a small set of changes for some driver
  core apis, and minor fixups. Included in here are:

   - sysfs_bin_attr_simple_read() helper added and used

   - device_show_string() helper added and used

  All usages of these were acked by the various maintainers. Also in
  here are:

   - kernfs minor cleanup

   - removed unused functions

   - typo fix in documentation

   - pay attention to sysfs_create_link() failures in module.c finally

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

* tag 'driver-core-6.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  device property: Fix a typo in the description of device_get_child_node_count()
  kernfs: mount: Remove unnecessary ‘NULL’ values from knparent
  scsi: Use device_show_string() helper for sysfs attributes
  platform/x86: Use device_show_string() helper for sysfs attributes
  perf: Use device_show_string() helper for sysfs attributes
  IB/qib: Use device_show_string() helper for sysfs attributes
  hwmon: Use device_show_string() helper for sysfs attributes
  driver core: Add device_show_string() helper for sysfs attributes
  treewide: Use sysfs_bin_attr_simple_read() helper
  sysfs: Add sysfs_bin_attr_simple_read() helper
  module: don't ignore sysfs_create_link() failures
  driver core: Remove unused platform_notify, platform_notify_remove

2 files changed, 30 insertions, 11 deletions

diff --git a/include/linux/device.h b/include/linux/device.h
index d4b50accff26..fc3bd7116ab9 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -132,6 +132,8 @@ ssize_t device_show_bool(struct device *dev, struct device_attribute *attr,
 			char *buf);
 ssize_t device_store_bool(struct device *dev, struct device_attribute *attr,
 			 const char *buf, size_t count);
+ssize_t device_show_string(struct device *dev, struct device_attribute *attr,
+			   char *buf);
 
 /**
  * DEVICE_ATTR - Define a device attribute.
@@ -251,6 +253,19 @@ ssize_t device_store_bool(struct device *dev, struct device_attribute *attr,
 	struct dev_ext_attribute dev_attr_##_name = \
 		{ __ATTR(_name, _mode, device_show_bool, device_store_bool), &(_var) }
 
+/**
+ * DEVICE_STRING_ATTR_RO - Define a device attribute backed by a r/o string.
+ * @_name: Attribute name.
+ * @_mode: File mode.
+ * @_var: Identifier of string.
+ *
+ * Like DEVICE_ULONG_ATTR(), but @_var is a string. Because the length of the
+ * string allocation is unknown, the attribute must be read-only.
+ */
+#define DEVICE_STRING_ATTR_RO(_name, _mode, _var) \
+	struct dev_ext_attribute dev_attr_##_name = \
+		{ __ATTR(_name, (_mode) & ~0222, device_show_string, NULL), (_var) }
+
 #define DEVICE_ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) \
 	struct device_attribute dev_attr_##_name =		\
 		__ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store)
@@ -1211,17 +1226,6 @@ int __must_check devm_device_add_group(struct device *dev,
 				       const struct attribute_group *grp);
 
 /*
- * Platform "fixup" functions - allow the platform to have their say
- * about devices and actions that the general device layer doesn't
- * know about.
- */
-/* Notify platform of device discovery */
-extern int (*platform_notify)(struct device *dev);
-
-extern int (*platform_notify_remove)(struct device *dev);
-
-
-/*
  * get_device - atomically increment the reference count for the device.
  *
  */
diff --git a/include/linux/sysfs.h b/include/linux/sysfs.h
index 326341c62385..a7d725fbf739 100644
--- a/include/linux/sysfs.h
+++ b/include/linux/sysfs.h
@@ -371,6 +371,17 @@ struct bin_attribute bin_attr_##_name = __BIN_ATTR_ADMIN_RO(_name, _size)
 #define BIN_ATTR_ADMIN_RW(_name, _size)					\
 struct bin_attribute bin_attr_##_name = __BIN_ATTR_ADMIN_RW(_name, _size)
 
+#define __BIN_ATTR_SIMPLE_RO(_name, _mode) {				\
+	.attr	= { .name = __stringify(_name), .mode = _mode },	\
+	.read	= sysfs_bin_attr_simple_read,				\
+}
+
+#define BIN_ATTR_SIMPLE_RO(_name)					\
+struct bin_attribute bin_attr_##_name = __BIN_ATTR_SIMPLE_RO(_name, 0444)
+
+#define BIN_ATTR_SIMPLE_ADMIN_RO(_name)					\
+struct bin_attribute bin_attr_##_name = __BIN_ATTR_SIMPLE_RO(_name, 0400)
+
 struct sysfs_ops {
 	ssize_t	(*show)(struct kobject *, struct attribute *, char *);
 	ssize_t	(*store)(struct kobject *, struct attribute *, const char *, size_t);
@@ -478,6 +489,10 @@ int sysfs_emit(char *buf, const char *fmt, ...);
 __printf(3, 4)
 int sysfs_emit_at(char *buf, int at, const char *fmt, ...);
 
+ssize_t sysfs_bin_attr_simple_read(struct file *file, struct kobject *kobj,
+				   struct bin_attribute *attr, char *buf,
+				   loff_t off, size_t count);
+
 #else /* CONFIG_SYSFS */
 
 static inline int sysfs_create_dir_ns(struct kobject *kobj, const void *ns)