static int twa_chrdev_open(struct inode *inode, struct file *file)
{
unsigned int minor_number;
int retval = TW_IOCTL_ERROR_OS_ENODEV;
static int twa_chrdev_open(struct inode *inode, struct file *file)
{
unsigned int minor_number;
int retval = TW_IOCTL_ERROR_OS_ENODEV;