Input: edt-ft5x06 - return -EFAULT on copy_to_user() error

copy_to_user() returns the number of bytes remaining, but we want a
negative error code here.
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

drivers/input/touchscreen/edt-ft5x06.c

@@ -566,9 +566,12 @@ static ssize_t edt_ft5x06_debugfs_raw_data_read(struct file *file,
 	}
 
 	read = min_t(size_t, count, tsdata->raw_bufsize - *off);
-	error = copy_to_user(buf, tsdata->raw_buffer + *off, read);
-	if (!error)
-		*off += read;
+	if (copy_to_user(buf, tsdata->raw_buffer + *off, read)) {
+		error = -EFAULT;
+		goto out;
+	}
+
+	*off += read;
 out:
 	mutex_unlock(&tsdata->mutex);
 	return error ?: read;