/*
* Open a tty line. Note that this can be called multiple times, so ->open can
* be >1. Only set up the tty struct if this is a "new" open, e.g. ->open was
* zero
*/
static int duart_open(struct tty_struct *tty, struct file *filp)
{
uart_state_t *us;
unsigned int line = tty->index;
unsigned long flags;
if ((line >= tty->driver->num) || !sb1250_duart_present[line])
return -ENODEV;
#ifdef DUART_SPEW
printk("duart_open called by %i (%s), tty is %p, rw is %p, ww is %p\n",
current->pid, current->comm, tty, tty->read_wait,
tty->write_wait);
#endif
us = uart_states + line;
tty->driver_data = us;
spin_lock_irqsave(&open_lock, flags);
if (!us->open) {
us->tty = tty;
us->tty->termios->c_cflag = us->last_cflags;
}
us->open++;
us->flags &= ~TX_INTEN;
duart_unmask_ints(line, M_DUART_IMR_RX);
spin_unlock_irqrestore(&open_lock, flags);
return 0;
}
/*
* Open a tty line. Note that this can be called multiple times, so ->open can
* be >1. Only set up the tty struct if this is a "new" open, e.g. ->open was
* zero
*/
static int duart_open(struct tty_struct *tty, struct file *filp)
{
uart_state_t *us;
unsigned int line = MINOR(tty->device) - tty->driver.minor_start;
unsigned long flags;
MOD_INC_USE_COUNT;
if ((line < 0) || (line >= DUART_MAX_LINE) || !sb1250_duart_present[line]) {
MOD_DEC_USE_COUNT;
return -ENODEV;
}
#ifdef DUART_SPEW
printk("duart_open called by %i (%s), tty is %p, rw is %p, ww is %p\n",
current->pid, current->comm, tty, tty->read_wait,
tty->write_wait);
#endif
us = uart_states + line;
tty->driver_data = us;
spin_lock_irqsave(&open_lock, flags);
if (!us->open) {
us->tty = tty;
us->tty->termios->c_cflag = us->last_cflags;
}
us->open++;
us->flags &= ~TX_INTEN;
duart_unmask_ints(line, M_DUART_IMR_RX);
spin_unlock_irqrestore(&open_lock, flags);
return 0;
}
/*
* Buffer up to count characters from buf to be written. If we don't have
* other characters buffered, enable the tx interrupt to start sending
*/
static int duart_write(struct tty_struct * tty, int from_user,
const unsigned char *buf, int count)
{
uart_state_t *us;
int c, t, total = 0;
unsigned long flags;
if (!tty) return 0;
us = tty->driver_data;
if (!us) return 0;
#ifdef DUART_SPEW
printk("duart_write called for %i chars by %i (%s)\n", count, current->pid, current->comm);
#endif
spin_lock_irqsave(&us->outp_lock, flags);
for (;;) {
c = count;
t = SERIAL_XMIT_SIZE - us->outp_tail;
if (t < c) c = t;
t = SERIAL_XMIT_SIZE - 1 - us->outp_count;
if (t < c) c = t;
if (c <= 0) break;
if (from_user) {
spin_unlock_irqrestore(&us->outp_lock, flags);
if (copy_from_user(us->outp_buf + us->outp_tail, buf, c)) {
return -EFAULT;
}
spin_lock_irqsave(&us->outp_lock, flags);
} else {
memcpy(us->outp_buf + us->outp_tail, buf, c);
}
us->outp_count += c;
us->outp_tail = (us->outp_tail + c) & (SERIAL_XMIT_SIZE - 1);
buf += c;
count -= c;
total += c;
}
spin_unlock_irqrestore(&us->outp_lock, flags);
if (us->outp_count && !tty->stopped &&
!tty->hw_stopped && !(us->flags & TX_INTEN)) {
us->flags |= TX_INTEN;
duart_unmask_ints(us->line, M_DUART_IMR_TX);
}
return total;
}
/* XXXKW locking? */
static void duart_start(struct tty_struct *tty)
{
uart_state_t *us = (uart_state_t *) tty->driver_data;
#ifdef DUART_SPEW
printk("duart_start called\n");
#endif
if (us->outp_count && !(us->flags & TX_INTEN)) {
us->flags |= TX_INTEN;
duart_unmask_ints(us->line, M_DUART_IMR_TX);
}
}
static void duart_flush_chars(struct tty_struct * tty)
{
uart_state_t *port;
if (!tty) return;
port = tty->driver_data;
if (!port) return;
if (port->outp_count <= 0 || tty->stopped || tty->hw_stopped) {
return;
}
port->flags |= TX_INTEN;
duart_unmask_ints(port->line, M_DUART_IMR_TX);
}
