diff --git a/drivers/usb/class/usbtmc.c b/drivers/usb/class/usbtmc.c
index 43a863c5cc430367ad045625eb4c3faecbfba7f9..0f5c05f6f9df0fd022a1eebf5d49d8c2931a6c47 100644
--- a/drivers/usb/class/usbtmc.c
+++ b/drivers/usb/class/usbtmc.c
@@ -21,6 +21,7 @@
 
 #include <linux/init.h>
 #include <linux/module.h>
+#include <linux/kernel.h>
 #include <linux/fs.h>
 #include <linux/uaccess.h>
 #include <linux/kref.h>
@@ -482,7 +483,6 @@ static ssize_t usbtmc_write(struct file *filp, const char __user *buf,
 	int retval;
 	int actual;
 	unsigned long int n_bytes;
-	int n;
 	int remaining;
 	int done;
 	int this_part;
@@ -526,11 +526,8 @@ static ssize_t usbtmc_write(struct file *filp, const char __user *buf,
 			goto exit;
 		}
 
-		n_bytes = 12 + this_part;
-		if (this_part % 4)
-			n_bytes += 4 - this_part % 4;
-			for (n = 12 + this_part; n < n_bytes; n++)
-				buffer[n] = 0;
+		n_bytes = roundup(12 + this_part, 4);
+		memset(buffer + 12 + this_part, 0, n_bytes - (12 + this_part));
 
 		retval = usb_bulk_msg(data->usb_dev,
 				      usb_sndbulkpipe(data->usb_dev,