USB: mon: no need to check return value of debugfs_create functions

When calling debugfs functions, there is no need to ever check the
return value.  The function can work or not, but the code logic should
never do something different based on this.

We do need to save the dentries for these files, so keep them around,
but no need to check if they are "valid" or not, as the code works just
as well either way.

Cc: Pete Zaitcev <zaitcev@kotori.zaitcev.us>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Cc: Fredrik Noring <noring@nocrew.org>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/mon/mon_text.c

@@ -700,7 +700,6 @@ static const struct file_operations mon_fops_text_u = {
 
 int mon_text_add(struct mon_bus *mbus, const struct usb_bus *ubus)
 {
-	struct dentry *d;
 	enum { NAMESZ = 10 };
 	char name[NAMESZ];
 	int busnum = ubus? ubus->busnum: 0;
@@ -713,42 +712,32 @@ int mon_text_add(struct mon_bus *mbus, const struct usb_bus *ubus)
 		rc = snprintf(name, NAMESZ, "%dt", busnum);
 		if (rc <= 0 || rc >= NAMESZ)
 			goto err_print_t;
-		d = debugfs_create_file(name, 0600, mon_dir, mbus,
+		mbus->dent_t = debugfs_create_file(name, 0600, mon_dir, mbus,
 							     &mon_fops_text_t);
-		if (d == NULL)
-			goto err_create_t;
-		mbus->dent_t = d;
 	}
 
 	rc = snprintf(name, NAMESZ, "%du", busnum);
 	if (rc <= 0 || rc >= NAMESZ)
 		goto err_print_u;
-	d = debugfs_create_file(name, 0600, mon_dir, mbus, &mon_fops_text_u);
-	if (d == NULL)
-		goto err_create_u;
-	mbus->dent_u = d;
+	mbus->dent_u = debugfs_create_file(name, 0600, mon_dir, mbus,
+					   &mon_fops_text_u);
 
 	rc = snprintf(name, NAMESZ, "%ds", busnum);
 	if (rc <= 0 || rc >= NAMESZ)
 		goto err_print_s;
-	d = debugfs_create_file(name, 0600, mon_dir, mbus, &mon_fops_stat);
-	if (d == NULL)
-		goto err_create_s;
-	mbus->dent_s = d;
+	mbus->dent_s = debugfs_create_file(name, 0600, mon_dir, mbus,
+					   &mon_fops_stat);
 
 	return 1;
 
-err_create_s:
 err_print_s:
 	debugfs_remove(mbus->dent_u);
 	mbus->dent_u = NULL;
-err_create_u:
 err_print_u:
 	if (ubus != NULL) {
 		debugfs_remove(mbus->dent_t);
 		mbus->dent_t = NULL;
 	}
-err_create_t:
 err_print_t:
 	return 0;
 }
@@ -756,8 +745,7 @@ err_print_t:
 void mon_text_del(struct mon_bus *mbus)
 {
 	debugfs_remove(mbus->dent_u);
-	if (mbus->dent_t != NULL)
-		debugfs_remove(mbus->dent_t);
+	debugfs_remove(mbus->dent_t);
 	debugfs_remove(mbus->dent_s);
 }
 
@@ -775,18 +763,7 @@ static void mon_text_ctor(void *mem)
 
 int __init mon_text_init(void)
 {
-	struct dentry *mondir;
-
-	mondir = debugfs_create_dir("usbmon", usb_debug_root);
-	if (IS_ERR(mondir)) {
-		/* debugfs not available, but we can use usbmon without it */
-		return 0;
-	}
-	if (mondir == NULL) {
-		printk(KERN_NOTICE TAG ": unable to create usbmon directory\n");
-		return -ENOMEM;
-	}
-	mon_dir = mondir;
+	mon_dir = debugfs_create_dir("usbmon", usb_debug_root);
 	return 0;
 }