static bool receive_chars(struct uart_port *port)
{
struct tty_port *tport = NULL;
int limit = 10000;
unsigned char ch;
char flag;
u8 status;
/* FIXME what is this trying to achieve? */
if (port->state != NULL) /* Unopened serial console */
tport = &port->state->port;
while (limit-- > 0) {
status = READ_SC_PORT(port, SR);
if (!(status & SR_RXRDY))
break;
ch = READ_SC_PORT(port, RHR);
flag = TTY_NORMAL;
port->icount.rx++;
if (unlikely(status & (SR_BREAK | SR_FRAME |
SR_PARITY | SR_OVERRUN))) {
if (status & SR_BREAK) {
status &= ~(SR_PARITY | SR_FRAME);
port->icount.brk++;
if (uart_handle_break(port))
continue;
} else if (status & SR_PARITY)
port->icount.parity++;
else if (status & SR_FRAME)
port->icount.frame++;
if (status & SR_OVERRUN)
port->icount.overrun++;
status &= port->read_status_mask;
if (status & SR_BREAK)
flag = TTY_BREAK;
else if (status & SR_PARITY)
flag = TTY_PARITY;
else if (status & SR_FRAME)
flag = TTY_FRAME;
}
if (uart_handle_sysrq_char(port, ch))
continue;
if (status & port->ignore_status_mask)
continue;
tty_insert_flip_char(tport, ch, flag);
}
return !!tport;
}
static struct tty_struct *receive_chars(struct uart_port *port)
{
struct tty_struct *tty = NULL;
int limit = 10000;
unsigned char ch;
char flag;
u8 status;
if (port->state != NULL)
tty = port->state->port.tty;
while (limit-- > 0) {
status = READ_SC_PORT(port, SR);
if (!(status & SR_RXRDY))
break;
ch = READ_SC_PORT(port, RHR);
flag = TTY_NORMAL;
port->icount.rx++;
if (unlikely(status & (SR_BREAK | SR_FRAME |
SR_PARITY | SR_OVERRUN))) {
if (status & SR_BREAK) {
status &= ~(SR_PARITY | SR_FRAME);
port->icount.brk++;
if (uart_handle_break(port))
continue;
} else if (status & SR_PARITY)
port->icount.parity++;
else if (status & SR_FRAME)
port->icount.frame++;
if (status & SR_OVERRUN)
port->icount.overrun++;
status &= port->read_status_mask;
if (status & SR_BREAK)
flag = TTY_BREAK;
else if (status & SR_PARITY)
flag = TTY_PARITY;
else if (status & SR_FRAME)
flag = TTY_FRAME;
}
if (uart_handle_sysrq_char(port, ch))
continue;
if (status & port->ignore_status_mask)
continue;
tty_insert_flip_char(tty, ch, flag);
}
return tty;
}
/* port->lock held by caller. */
static void sc26xx_start_tx(struct uart_port *port)
{
struct circ_buf *xmit = &port->state->xmit;
while (!uart_circ_empty(xmit)) {
if (!(READ_SC_PORT(port, SR) & SR_TXRDY)) {
sc26xx_enable_irq(port, IMR_TXRDY);
break;
}
WRITE_SC_PORT(port, THR, xmit->buf[xmit->tail]);
xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
port->icount.tx++;
}
}
static void sc26xx_console_putchar(struct uart_port *port, char c)
{
unsigned long flags;
int limit = 1000000;
spin_lock_irqsave(&port->lock, flags);
while (limit-- > 0) {
if (READ_SC_PORT(port, SR) & SR_TXRDY) {
WRITE_SC_PORT(port, THR, c);
break;
}
udelay(2);
}
spin_unlock_irqrestore(&port->lock, flags);
}
static void transmit_chars(struct uart_port *port)
{
struct circ_buf *xmit;
if (!port->state)
return;
xmit = &port->state->xmit;
if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
sc26xx_disable_irq(port, IMR_TXRDY);
return;
}
while (!uart_circ_empty(xmit)) {
if (!(READ_SC_PORT(port, SR) & SR_TXRDY))
break;
WRITE_SC_PORT(port, THR, xmit->buf[xmit->tail]);
xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
port->icount.tx++;
}
if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
uart_write_wakeup(port);
}
/* port->lock is not held. */
static void sc26xx_set_termios(struct uart_port *port, struct ktermios *termios,
struct ktermios *old)
{
unsigned int baud = uart_get_baud_rate(port, termios, old, 0, 4000000);
unsigned int quot = uart_get_divisor(port, baud);
unsigned int iflag, cflag;
unsigned long flags;
u8 mr1, mr2, csr;
spin_lock_irqsave(&port->lock, flags);
while ((READ_SC_PORT(port, SR) & ((1 << 3) | (1 << 2))) != 0xc)
udelay(2);
WRITE_SC_PORT(port, CR, CR_DIS_TX | CR_DIS_RX);
iflag = termios->c_iflag;
cflag = termios->c_cflag;
port->read_status_mask = SR_OVERRUN;
if (iflag & INPCK)
port->read_status_mask |= SR_PARITY | SR_FRAME;
if (iflag & (BRKINT | PARMRK))
port->read_status_mask |= SR_BREAK;
port->ignore_status_mask = 0;
if (iflag & IGNBRK)
port->ignore_status_mask |= SR_BREAK;
if ((cflag & CREAD) == 0)
port->ignore_status_mask |= SR_BREAK | SR_FRAME |
SR_PARITY | SR_OVERRUN;
switch (cflag & CSIZE) {
case CS5:
mr1 = 0x00;
break;
case CS6:
mr1 = 0x01;
break;
case CS7:
mr1 = 0x02;
break;
default:
case CS8:
mr1 = 0x03;
break;
}
mr2 = 0x07;
if (cflag & CSTOPB)
mr2 = 0x0f;
if (cflag & PARENB) {
if (cflag & PARODD)
mr1 |= (1 << 2);
} else
mr1 |= (2 << 3);
switch (baud) {
case 50:
csr = 0x00;
break;
case 110:
csr = 0x11;
break;
case 134:
csr = 0x22;
break;
case 200:
csr = 0x33;
break;
case 300:
csr = 0x44;
break;
case 600:
csr = 0x55;
break;
case 1200:
csr = 0x66;
break;
case 2400:
csr = 0x88;
break;
case 4800:
csr = 0x99;
break;
default:
case 9600:
csr = 0xbb;
break;
case 19200:
csr = 0xcc;
break;
}
WRITE_SC_PORT(port, CR, CR_RES_MR);
WRITE_SC_PORT(port, MRx, mr1);
WRITE_SC_PORT(port, MRx, mr2);
WRITE_SC(port, ACR, 0x80);
WRITE_SC_PORT(port, CSR, csr);
/* reset tx and rx */
WRITE_SC_PORT(port, CR, CR_RES_RX);
WRITE_SC_PORT(port, CR, CR_RES_TX);
WRITE_SC_PORT(port, CR, CR_ENA_TX | CR_ENA_RX);
while ((READ_SC_PORT(port, SR) & ((1 << 3) | (1 << 2))) != 0xc)
udelay(2);
/* XXX */
uart_update_timeout(port, cflag,
(port->uartclk / (16 * quot)));
spin_unlock_irqrestore(&port->lock, flags);
}
/* port->lock is not held. */
static unsigned int sc26xx_tx_empty(struct uart_port *port)
{
return (READ_SC_PORT(port, SR) & SR_TXRDY) ? TIOCSER_TEMT : 0;
}
