static int serial_link_irq_chain(struct uart_8250_port *up)
{
struct irq_info *i = irq_lists + up->port.irq;
int ret, irq_flags = up->port.flags & UPF_SHARE_IRQ ? SA_SHIRQ : 0;
spin_lock_irq(&i->lock);
if (i->head) {
list_add(&up->list, i->head);
spin_unlock_irq(&i->lock);
ret = 0;
} else {
INIT_LIST_HEAD(&up->list);
i->head = &up->list;
spin_unlock_irq(&i->lock);
ret = request_irq(up->port.irq, serial8250_interrupt,
irq_flags, "serial", i);
if (ret < 0)
serial_do_unlink(i, up);
}
return ret;
}
static int serial_link_irq_chain(struct uart_sio_port *up)
{
struct irq_info *i = irq_lists + up->port.irq;
int ret, irq_flags = 0;
spin_lock_irq(&i->lock);
if (i->head) {
list_add(&up->list, i->head);
spin_unlock_irq(&i->lock);
ret = 0;
} else {
INIT_LIST_HEAD(&up->list);
i->head = &up->list;
spin_unlock_irq(&i->lock);
ret = request_irq(up->port.irq, m32r_sio_interrupt,
irq_flags, "SIO0-RX", i);
ret |= request_irq(up->port.irq + 1, m32r_sio_interrupt,
irq_flags, "SIO0-TX", i);
if (ret < 0)
serial_do_unlink(i, up);
}
return ret;
}
static void serial_unlink_irq_chain(struct uart_8250_port *up)
{
struct irq_info *i = irq_lists + up->port.irq;
BUG_ON(i->head == NULL);
if (list_empty(i->head))
free_irq(up->port.irq, i);
serial_do_unlink(i, up);
}