[PATCH 13/20] headers: add class_create() single-argument backport for kernels < 6.4

From: Yi Cong <[email protected]>

In v6.4 class_create() was simplified to take only the name argument,
using THIS_MODULE implicitly. For older kernels, provide a wrapper
that forwards to the two-argument __class_create() macro.

Signed-off-by: Yi Cong <[email protected]>
---
 backport/backport-include/linux/device.h | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/backport/backport-include/linux/device.h b/backport/backport-include/linux/device.h
index 06595285..069337b7 100644
--- a/backport/backport-include/linux/device.h
+++ b/backport/backport-include/linux/device.h
@@ -12,4 +12,18 @@
 	struct device_attribute dev_attr_##_name = __ATTR_RO_MODE(_name, 0400)
 #endif
 
+#if LINUX_VERSION_IS_LESS(6,4,0)
+/*
+ * class_create() in v6.4+ takes only the name argument and uses
+ * THIS_MODULE implicitly.  For older kernels, provide a wrapper
+ * that forwards to the 2-argument macro version.
+ */
+#undef class_create
+#define class_create(name) \
+({ \
+	static struct lock_class_key __key; \
+	__class_create(THIS_MODULE, (name), &__key); \
+})
+#endif
+
 #endif /* __BACKPORT_DEVICE_H_ */
-- 
2.43.0