cxl/debug: Move debugfs init to cxl_core_init()

In preparation for a new cxl debugfs file, move 'cxl' directory
establishment and teardown to the core and let subsequent init routines
reference that setup.
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/165603884654.551046.4962104601691723080.stgit@dwillia2-xfhSigned-off-by: Dan Williams <dan.j.williams@intel.com>

drivers/cxl/core/core.h

@@ -17,9 +17,9 @@ int cxl_send_cmd(struct cxl_memdev *cxlmd, struct cxl_send_command __user *s);
 void __iomem *devm_cxl_iomap_block(struct device *dev, resource_size_t addr,
 				   resource_size_t length);
 
+struct dentry *cxl_debugfs_create_dir(const char *dir);
 int cxl_memdev_init(void);
 void cxl_memdev_exit(void);
 void cxl_mbox_init(void);
-void cxl_mbox_exit(void);
 
 #endif /* __CXL_CORE_H__ */

drivers/cxl/core/mbox.c

@@ -857,19 +857,11 @@ struct cxl_dev_state *cxl_dev_state_create(struct device *dev)
 }
 EXPORT_SYMBOL_NS_GPL(cxl_dev_state_create, CXL);
 
-static struct dentry *cxl_debugfs;
-
 void __init cxl_mbox_init(void)
 {
 	struct dentry *mbox_debugfs;
 
-	cxl_debugfs = debugfs_create_dir("cxl", NULL);
-	mbox_debugfs = debugfs_create_dir("mbox", cxl_debugfs);
+	mbox_debugfs = cxl_debugfs_create_dir("mbox");
 	debugfs_create_bool("raw_allow_all", 0600, mbox_debugfs,
 			    &cxl_raw_allow_all);
 }
-
-void cxl_mbox_exit(void)
-{
-	debugfs_remove_recursive(cxl_debugfs);
-}

drivers/cxl/core/port.c

@@ -2,6 +2,7 @@
 /* Copyright(c) 2020 Intel Corporation. All rights reserved. */
 #include <linux/io-64-nonatomic-lo-hi.h>
 #include <linux/workqueue.h>
+#include <linux/debugfs.h>
 #include <linux/device.h>
 #include <linux/module.h>
 #include <linux/pci.h>
@@ -1499,10 +1500,19 @@ struct bus_type cxl_bus_type = {
 };
 EXPORT_SYMBOL_NS_GPL(cxl_bus_type, CXL);
 
+static struct dentry *cxl_debugfs;
+
+struct dentry *cxl_debugfs_create_dir(const char *dir)
+{
+	return debugfs_create_dir(dir, cxl_debugfs);
+}
+
 static __init int cxl_core_init(void)
 {
 	int rc;
 
+	cxl_debugfs = debugfs_create_dir("cxl", NULL);
+
 	cxl_mbox_init();
 
 	rc = cxl_memdev_init();
@@ -1525,7 +1535,6 @@ static __init int cxl_core_init(void)
 	destroy_workqueue(cxl_bus_wq);
 err_wq:
 	cxl_memdev_exit();
-	cxl_mbox_exit();
 	return rc;
 }
 
@@ -1534,7 +1543,7 @@ static void cxl_core_exit(void)
 	bus_unregister(&cxl_bus_type);
 	destroy_workqueue(cxl_bus_wq);
 	cxl_memdev_exit();
-	cxl_mbox_exit();
+	debugfs_remove_recursive(cxl_debugfs);
 }
 
 module_init(cxl_core_init);