static unsigned int s3c24xx_serial_tx_empty(struct uart_port *port)
{
struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
unsigned long ufstat = rd_regl(port, S3C2410_UFSTAT);
unsigned long ufcon = rd_regl(port, S3C2410_UFCON);
if (ufcon & S3C2410_UFCON_FIFOMODE) {
if ((ufstat & info->tx_fifomask) != 0 ||
(ufstat & info->tx_fifofull))
return 0;
return 1;
}
return s3c24xx_serial_txempty_nofifo(port);
}
static void s3c24xx_serial_rx_enable(struct uart_port *port)
{
unsigned long flags;
unsigned int ucon, ufcon;
int count = 10000;
spin_lock_irqsave(&port->lock, flags);
while (--count && !s3c24xx_serial_txempty_nofifo(port))
udelay(100);
ufcon = rd_regl(port, S3C2410_UFCON);
ufcon |= S3C2410_UFCON_RESETRX;
wr_regl(port, S3C2410_UFCON, ufcon);
ucon = rd_regl(port, S3C2410_UCON);
ucon |= S3C2410_UCON_RXIRQMODE;
wr_regl(port, S3C2410_UCON, ucon);
rx_enabled(port) = 1;
spin_unlock_irqrestore(&port->lock, flags);
}
static void s3c24xx_serial_rx_drain_fifo(struct s3c24xx_uart_port *ourport)
{
struct uart_port *port = &ourport->port;
unsigned int ufcon, ch, flag, ufstat, uerstat;
unsigned int fifocnt = 0;
int max_count = port->fifosize;
while (max_count-- > 0) {
/*
* Receive all characters known to be in FIFO
* before reading FIFO level again
*/
if (fifocnt == 0) {
ufstat = rd_regl(port, S3C2410_UFSTAT);
fifocnt = s3c24xx_serial_rx_fifocnt(ourport, ufstat);
if (fifocnt == 0)
break;
}
fifocnt--;
uerstat = rd_regl(port, S3C2410_UERSTAT);
ch = rd_regb(port, S3C2410_URXH);
if (port->flags & UPF_CONS_FLOW) {
int txe = s3c24xx_serial_txempty_nofifo(port);
if (rx_enabled(port)) {
if (!txe) {
rx_enabled(port) = 0;
continue;
}
} else {
if (txe) {
ufcon = rd_regl(port, S3C2410_UFCON);
ufcon |= S3C2410_UFCON_RESETRX;
wr_regl(port, S3C2410_UFCON, ufcon);
rx_enabled(port) = 1;
return;
}
continue;
}
}
/* insert the character into the buffer */
flag = TTY_NORMAL;
port->icount.rx++;
if (unlikely(uerstat & S3C2410_UERSTAT_ANY)) {
dbg("rxerr: port ch=0x%02x, rxs=0x%08x\n",
ch, uerstat);
/* check for break */
if (uerstat & S3C2410_UERSTAT_BREAK) {
dbg("break!\n");
port->icount.brk++;
if (uart_handle_break(port))
continue; /* Ignore character */
}
if (uerstat & S3C2410_UERSTAT_FRAME)
port->icount.frame++;
if (uerstat & S3C2410_UERSTAT_OVERRUN)
port->icount.overrun++;
uerstat &= port->read_status_mask;
if (uerstat & S3C2410_UERSTAT_BREAK)
flag = TTY_BREAK;
else if (uerstat & S3C2410_UERSTAT_PARITY)
flag = TTY_PARITY;
else if (uerstat & (S3C2410_UERSTAT_FRAME |
S3C2410_UERSTAT_OVERRUN))
flag = TTY_FRAME;
}
if (uart_handle_sysrq_char(port, ch))
continue; /* Ignore character */
uart_insert_char(port, uerstat, S3C2410_UERSTAT_OVERRUN,
ch, flag);
}
tty_flip_buffer_push(&port->state->port);
}
static irqreturn_t
s3c24xx_serial_rx_chars(int irq, void *dev_id)
{
struct s3c24xx_uart_port *ourport = dev_id;
struct uart_port *port = &ourport->port;
struct tty_struct *tty = port->state->port.tty;
unsigned int ufcon, ch, flag, ufstat, uerstat;
int max_count = 64;
while (max_count-- > 0) {
ufcon = rd_regl(port, S3C2410_UFCON);
ufstat = rd_regl(port, S3C2410_UFSTAT);
if (s3c24xx_serial_rx_fifocnt(ourport, ufstat) == 0)
break;
uerstat = rd_regl(port, S3C2410_UERSTAT);
ch = rd_regb(port, S3C2410_URXH);
if (port->flags & UPF_CONS_FLOW) {
int txe = s3c24xx_serial_txempty_nofifo(port);
if (rx_enabled(port)) {
if (!txe) {
rx_enabled(port) = 0;
continue;
}
} else {
if (txe) {
ufcon |= S3C2410_UFCON_RESETRX;
wr_regl(port, S3C2410_UFCON, ufcon);
rx_enabled(port) = 1;
goto out;
}
continue;
}
}
/* insert the character into the buffer */
flag = TTY_NORMAL;
port->icount.rx++;
if (unlikely(uerstat & S3C2410_UERSTAT_ANY)) {
dbg("rxerr: port ch=0x%02x, rxs=0x%08x\n",
ch, uerstat);
/* check for break */
if (uerstat & S3C2410_UERSTAT_BREAK) {
dbg("break!\n");
port->icount.brk++;
if (uart_handle_break(port))
goto ignore_char;
}
if (uerstat & S3C2410_UERSTAT_FRAME)
port->icount.frame++;
if (uerstat & S3C2410_UERSTAT_OVERRUN)
port->icount.overrun++;
uerstat &= port->read_status_mask;
if (uerstat & S3C2410_UERSTAT_BREAK)
flag = TTY_BREAK;
else if (uerstat & S3C2410_UERSTAT_PARITY)
flag = TTY_PARITY;
else if (uerstat & (S3C2410_UERSTAT_FRAME |
S3C2410_UERSTAT_OVERRUN))
flag = TTY_FRAME;
}
if (uart_handle_sysrq_char(port, ch))
goto ignore_char;
uart_insert_char(port, uerstat, S3C2410_UERSTAT_OVERRUN,
ch, flag);
ignore_char:
continue;
}
tty_flip_buffer_push(tty);
out:
return IRQ_HANDLED;
}
static irqreturn_t
s3c24xx_serial_rx_chars(int irq, void *dev_id, struct pt_regs *regs)
{
struct s3c24xx_uart_port *ourport = dev_id;
struct uart_port *port = &ourport->port;
struct tty_struct *tty = port->info->tty;
unsigned int ufcon, ch, flag, ufstat, uerstat;
int max_count = 64;
while (max_count-- > 0) {
ufcon = rd_regl(port, S3C2410_UFCON);
ufstat = rd_regl(port, S3C2410_UFSTAT);
if (s3c24xx_serial_rx_fifocnt(ourport, ufstat) == 0)
break;
if (tty->flip.count >= TTY_FLIPBUF_SIZE) {
if (tty->low_latency)
tty_flip_buffer_push(tty);
/*
* If this failed then we will throw away the
* bytes but must do so to clear interrupts
*/
}
uerstat = rd_regl(port, S3C2410_UERSTAT);
ch = rd_regb(port, S3C2410_URXH);
if (port->flags & UPF_CONS_FLOW) {
int txe = s3c24xx_serial_txempty_nofifo(port);
if (rx_enabled(port)) {
if (!txe) {
rx_enabled(port) = 0;
continue;
}
} else {
if (txe) {
ufcon |= S3C2410_UFCON_RESETRX;
wr_regl(port, S3C2410_UFCON, ufcon);
rx_enabled(port) = 1;
goto out;
}
continue;
}
}
/* insert the character into the buffer */
flag = TTY_NORMAL;
port->icount.rx++;
if (uerstat & S3C2410_UERSTAT_ANY) {
dbg("rxerr: port ch=0x%02x, rxs=0x%08x\n",
ch, uerstat);
/* check for break */
if (uerstat & S3C2410_UERSTAT_BREAK) {
dbg("break!\n");
port->icount.brk++;
if (uart_handle_break(port))
goto ignore_char;
}
if (uerstat & S3C2410_UERSTAT_FRAME)
port->icount.frame++;
if (uerstat & S3C2410_UERSTAT_OVERRUN)
port->icount.overrun++;
uerstat &= port->read_status_mask;
if (uerstat & S3C2410_UERSTAT_BREAK)
flag = TTY_BREAK;
else if (uerstat & S3C2410_UERSTAT_PARITY)
flag = TTY_PARITY;
else if (uerstat & ( S3C2410_UERSTAT_FRAME | S3C2410_UERSTAT_OVERRUN))
flag = TTY_FRAME;
}
if (uart_handle_sysrq_char(port, ch, regs))
goto ignore_char;
if ((uerstat & port->ignore_status_mask) == 0) {
tty_insert_flip_char(tty, ch, flag);
}
if ((uerstat & S3C2410_UERSTAT_OVERRUN) &&
tty->flip.count < TTY_FLIPBUF_SIZE) {
/*
* Overrun is special, since it's reported
* immediately, and doesn't affect the current
* character.
*/
tty_insert_flip_char(tty, 0, TTY_OVERRUN);
}
ignore_char:
continue;
}
tty_flip_buffer_push(tty);
out:
return IRQ_HANDLED;
}
