/*
* Turn power on or off to the SCC and associated stuff
* (port drivers, modem, IR port, etc.)
* Returns the number of milliseconds we should wait before
* trying to use the port.
*/
static int pmz_set_scc_power(struct uart_pmac_port *uap, int state)
{
int delay = 0;
int rc;
if (state) {
rc = pmac_call_feature(
PMAC_FTR_SCC_ENABLE, uap->node, uap->port_type, 1);
pmz_debug("port power on result: %d\n", rc);
if (ZS_IS_INTMODEM(uap)) {
rc = pmac_call_feature(
PMAC_FTR_MODEM_ENABLE, uap->node, 0, 1);
delay = 2500; /* wait for 2.5s before using */
pmz_debug("modem power result: %d\n", rc);
}
} else {
/* TODO: Make that depend on a timer, don't power down
* immediately
*/
if (ZS_IS_INTMODEM(uap)) {
rc = pmac_call_feature(
PMAC_FTR_MODEM_ENABLE, uap->node, 0, 0);
pmz_debug("port power off result: %d\n", rc);
}
pmac_call_feature(PMAC_FTR_SCC_ENABLE, uap->node, uap->port_type, 0);
}
return delay;
}
static int pmz_suspend(struct macio_dev *mdev, pm_message_t pm_state)
{
struct uart_pmac_port *uap = dev_get_drvdata(&mdev->ofdev.dev);
struct uart_state *state;
unsigned long flags;
if (uap == NULL) {
printk("HRM... pmz_suspend with NULL uap\n");
return 0;
}
if (pm_state.event == mdev->ofdev.dev.power.power_state.event)
return 0;
pmz_debug("suspend, switching to state %d\n", pm_state);
state = pmz_uart_reg.state + uap->port.line;
mutex_lock(&pmz_irq_mutex);
mutex_lock(&state->mutex);
spin_lock_irqsave(&uap->port.lock, flags);
if (ZS_IS_OPEN(uap) || ZS_IS_CONS(uap)) {
/* Disable receiver and transmitter. */
uap->curregs[R3] &= ~RxENABLE;
uap->curregs[R5] &= ~TxENABLE;
/* Disable all interrupts and BRK assertion. */
uap->curregs[R1] &= ~(EXT_INT_ENAB | TxINT_ENAB | RxINT_MASK);
uap->curregs[R5] &= ~SND_BRK;
pmz_load_zsregs(uap, uap->curregs);
uap->flags |= PMACZILOG_FLAG_IS_ASLEEP;
mb();
}
spin_unlock_irqrestore(&uap->port.lock, flags);
if (ZS_IS_OPEN(uap) || ZS_IS_OPEN(uap->mate))
if (ZS_IS_ASLEEP(uap->mate) && ZS_IS_IRQ_ON(pmz_get_port_A(uap))) {
pmz_get_port_A(uap)->flags &= ~PMACZILOG_FLAG_IS_IRQ_ON;
disable_irq(uap->port.irq);
}
if (ZS_IS_CONS(uap))
uap->port.cons->flags &= ~CON_ENABLED;
/* Shut the chip down */
pmz_set_scc_power(uap, 0);
mutex_unlock(&state->mutex);
mutex_unlock(&pmz_irq_mutex);
pmz_debug("suspend, switching complete\n");
mdev->ofdev.dev.power.power_state = pm_state;
return 0;
}
static void pmz_shutdown(struct uart_port *port)
{
struct uart_pmac_port *uap = to_pmz(port);
unsigned long flags;
pmz_debug("pmz: shutdown()\n");
if (uap->node == NULL)
return;
mutex_lock(&pmz_irq_mutex);
/* Release interrupt handler */
free_irq(uap->port.irq, uap);
spin_lock_irqsave(&port->lock, flags);
uap->flags &= ~PMACZILOG_FLAG_IS_OPEN;
if (!ZS_IS_OPEN(uap->mate))
pmz_get_port_A(uap)->flags &= ~PMACZILOG_FLAG_IS_IRQ_ON;
/* Disable interrupts */
if (!ZS_IS_ASLEEP(uap)) {
uap->curregs[R1] &= ~(EXT_INT_ENAB | TxINT_ENAB | RxINT_MASK);
write_zsreg(uap, R1, uap->curregs[R1]);
zssync(uap);
}
if (ZS_IS_CONS(uap) || ZS_IS_ASLEEP(uap)) {
spin_unlock_irqrestore(&port->lock, flags);
mutex_unlock(&pmz_irq_mutex);
return;
}
/* Disable receiver and transmitter. */
uap->curregs[R3] &= ~RxENABLE;
uap->curregs[R5] &= ~TxENABLE;
/* Disable all interrupts and BRK assertion. */
uap->curregs[R5] &= ~SND_BRK;
pmz_maybe_update_regs(uap);
/* Shut the chip down */
pmz_set_scc_power(uap, 0);
spin_unlock_irqrestore(&port->lock, flags);
mutex_unlock(&pmz_irq_mutex);
pmz_debug("pmz: shutdown() done.\n");
}
static void __pmz_set_termios(struct uart_port *port, struct ktermios *termios,
struct ktermios *old)
{
struct uart_pmac_port *uap = to_pmz(port);
unsigned long baud;
pmz_debug("pmz: set_termios()\n");
if (ZS_IS_ASLEEP(uap))
return;
memcpy(&uap->termios_cache, termios, sizeof(struct ktermios));
/* XXX Check which revs of machines actually allow 1 and 4Mb speeds
* on the IR dongle. Note that the IRTTY driver currently doesn't know
* about the FIR mode and high speed modes. So these are unused. For
* implementing proper support for these, we should probably add some
* DMA as well, at least on the Rx side, which isn't a simple thing
* at this point.
*/
if (ZS_IS_IRDA(uap)) {
/* Calc baud rate */
baud = uart_get_baud_rate(port, termios, old, 1200, 4000000);
pmz_debug("pmz: switch IRDA to %ld bauds\n", baud);
/* Cet the irda codec to the right rate */
pmz_irda_setup(uap, &baud);
/* Set final baud rate */
pmz_convert_to_zs(uap, termios->c_cflag, termios->c_iflag, baud);
pmz_load_zsregs(uap, uap->curregs);
zssync(uap);
} else {
baud = uart_get_baud_rate(port, termios, old, 1200, 230400);
pmz_convert_to_zs(uap, termios->c_cflag, termios->c_iflag, baud);
/* Make sure modem status interrupts are correctly configured */
if (UART_ENABLE_MS(&uap->port, termios->c_cflag)) {
uap->curregs[R15] |= DCDIE | SYNCIE | CTSIE;
uap->flags |= PMACZILOG_FLAG_MODEM_STATUS;
} else {
uap->curregs[R15] &= ~(DCDIE | SYNCIE | CTSIE);
uap->flags &= ~PMACZILOG_FLAG_MODEM_STATUS;
}
/* Load registers to the chip */
pmz_maybe_update_regs(uap);
}
uart_update_timeout(port, termios->c_cflag, baud);
pmz_debug("pmz: set_termios() done.\n");
}
/*
* Stop Rx side, basically disable emitting of
* Rx interrupts on the port. We don't disable the rx
* side of the chip proper though
* The port lock is held.
*/
static void pmz_stop_rx(struct uart_port *port)
{
struct uart_pmac_port *uap = to_pmz(port);
if (ZS_IS_ASLEEP(uap) || uap->node == NULL)
return;
pmz_debug("pmz: stop_rx()()\n");
/* Disable all RX interrupts. */
uap->curregs[R1] &= ~RxINT_MASK;
pmz_maybe_update_regs(uap);
pmz_debug("pmz: stop_rx() done.\n");
}
/*
* We do like sunzilog to avoid disrupting pending Tx
* Reprogram the Zilog channel HW registers with the copies found in the
* software state struct. If the transmitter is busy, we defer this update
* until the next TX complete interrupt. Else, we do it right now.
*
* The UART port lock must be held and local interrupts disabled.
*/
static void pmz_maybe_update_regs(struct uart_pmac_port *uap)
{
if (!ZS_REGS_HELD(uap)) {
if (ZS_TX_ACTIVE(uap)) {
uap->flags |= PMACZILOG_FLAG_REGS_HELD;
} else {
pmz_debug("pmz: maybe_update_regs: updating\n");
pmz_load_zsregs(uap, uap->curregs);
}
}
}
/*
* Kick the Tx side.
* The port lock is held and interrupts are disabled.
*/
static void pmz_start_tx(struct uart_port *port)
{
struct uart_pmac_port *uap = to_pmz(port);
unsigned char status;
pmz_debug("pmz: start_tx()\n");
uap->flags |= PMACZILOG_FLAG_TX_ACTIVE;
uap->flags &= ~PMACZILOG_FLAG_TX_STOPPED;
if (ZS_IS_ASLEEP(uap) || uap->node == NULL)
return;
status = read_zsreg(uap, R0);
/* TX busy? Just wait for the TX done interrupt. */
if (!(status & Tx_BUF_EMP))
return;
/* Send the first character to jump-start the TX done
* IRQ sending engine.
*/
if (port->x_char) {
write_zsdata(uap, port->x_char);
zssync(uap);
port->icount.tx++;
port->x_char = 0;
} else {
struct circ_buf *xmit = &port->info->xmit;
write_zsdata(uap, xmit->buf[xmit->tail]);
zssync(uap);
xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
port->icount.tx++;
if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
uart_write_wakeup(&uap->port);
}
pmz_debug("pmz: start_tx() done.\n");
}
/*
* Set Modem Control (RTS & DTR) bits
* The port lock is held and interrupts are disabled.
* Note: Shall we really filter out RTS on external ports or
* should that be dealt at higher level only ?
*/
static void pmz_set_mctrl(struct uart_port *port, unsigned int mctrl)
{
struct uart_pmac_port *uap = to_pmz(port);
unsigned char set_bits, clear_bits;
/* Do nothing for irda for now... */
if (ZS_IS_IRDA(uap))
return;
/* We get called during boot with a port not up yet */
if (ZS_IS_ASLEEP(uap) ||
!(ZS_IS_OPEN(uap) || ZS_IS_CONS(uap)))
return;
set_bits = clear_bits = 0;
if (ZS_IS_INTMODEM(uap)) {
if (mctrl & TIOCM_RTS)
set_bits |= RTS;
else
clear_bits |= RTS;
}
if (mctrl & TIOCM_DTR)
set_bits |= DTR;
else
clear_bits |= DTR;
/* NOTE: Not subject to 'transmitter active' rule. */
uap->curregs[R5] |= set_bits;
uap->curregs[R5] &= ~clear_bits;
if (ZS_IS_ASLEEP(uap))
return;
write_zsreg(uap, R5, uap->curregs[R5]);
pmz_debug("pmz_set_mctrl: set bits: %x, clear bits: %x -> %x\n",
set_bits, clear_bits, uap->curregs[R5]);
zssync(uap);
}
/*
* This is the "normal" startup routine, using the above one
* wrapped with the lock and doing a schedule delay
*/
static int pmz_startup(struct uart_port *port)
{
struct uart_pmac_port *uap = to_pmz(port);
unsigned long flags;
int pwr_delay = 0;
pmz_debug("pmz: startup()\n");
if (ZS_IS_ASLEEP(uap))
return -EAGAIN;
if (uap->node == NULL)
return -ENODEV;
mutex_lock(&pmz_irq_mutex);
uap->flags |= PMACZILOG_FLAG_IS_OPEN;
/* A console is never powered down. Else, power up and
* initialize the chip
*/
if (!ZS_IS_CONS(uap)) {
spin_lock_irqsave(&port->lock, flags);
pwr_delay = __pmz_startup(uap);
spin_unlock_irqrestore(&port->lock, flags);
}
pmz_get_port_A(uap)->flags |= PMACZILOG_FLAG_IS_IRQ_ON;
if (request_irq(uap->port.irq, pmz_interrupt, IRQF_SHARED, "PowerMac Zilog", uap)) {
dev_err(&uap->dev->ofdev.dev,
"Unable to register zs interrupt handler.\n");
pmz_set_scc_power(uap, 0);
mutex_unlock(&pmz_irq_mutex);
return -ENXIO;
}
mutex_unlock(&pmz_irq_mutex);
/* Right now, we deal with delay by blocking here, I'll be
* smarter later on
*/
if (pwr_delay != 0) {
pmz_debug("pmz: delaying %d ms\n", pwr_delay);
msleep(pwr_delay);
}
/* IrDA reset is done now */
if (ZS_IS_IRDA(uap))
pmz_irda_reset(uap);
/* Enable interrupts emission from the chip */
spin_lock_irqsave(&port->lock, flags);
uap->curregs[R1] |= INT_ALL_Rx | TxINT_ENAB;
if (!ZS_IS_EXTCLK(uap))
uap->curregs[R1] |= EXT_INT_ENAB;
write_zsreg(uap, R1, uap->curregs[R1]);
spin_unlock_irqrestore(&port->lock, flags);
pmz_debug("pmz: startup() done.\n");
return 0;
}
/* Hrm... we register that twice, fixme later.... */
static irqreturn_t pmz_interrupt(int irq, void *dev_id)
{
struct uart_pmac_port *uap = dev_id;
struct uart_pmac_port *uap_a;
struct uart_pmac_port *uap_b;
int rc = IRQ_NONE;
struct tty_struct *tty;
u8 r3;
uap_a = pmz_get_port_A(uap);
uap_b = uap_a->mate;
spin_lock(&uap_a->port.lock);
r3 = read_zsreg(uap_a, R3);
#ifdef DEBUG_HARD
pmz_debug("irq, r3: %x\n", r3);
#endif
/* Channel A */
tty = NULL;
if (r3 & (CHAEXT | CHATxIP | CHARxIP)) {
write_zsreg(uap_a, R0, RES_H_IUS);
zssync(uap_a);
if (r3 & CHAEXT)
pmz_status_handle(uap_a);
if (r3 & CHARxIP)
tty = pmz_receive_chars(uap_a);
if (r3 & CHATxIP)
pmz_transmit_chars(uap_a);
rc = IRQ_HANDLED;
}
spin_unlock(&uap_a->port.lock);
if (tty != NULL)
tty_flip_buffer_push(tty);
if (uap_b->node == NULL)
goto out;
spin_lock(&uap_b->port.lock);
tty = NULL;
if (r3 & (CHBEXT | CHBTxIP | CHBRxIP)) {
write_zsreg(uap_b, R0, RES_H_IUS);
zssync(uap_b);
if (r3 & CHBEXT)
pmz_status_handle(uap_b);
if (r3 & CHBRxIP)
tty = pmz_receive_chars(uap_b);
if (r3 & CHBTxIP)
pmz_transmit_chars(uap_b);
rc = IRQ_HANDLED;
}
spin_unlock(&uap_b->port.lock);
if (tty != NULL)
tty_flip_buffer_push(tty);
out:
#ifdef DEBUG_HARD
pmz_debug("irq done.\n");
#endif
return rc;
}
static struct tty_struct *pmz_receive_chars(struct uart_pmac_port *uap)
{
struct tty_struct *tty = NULL;
unsigned char ch, r1, drop, error, flag;
int loops = 0;
/* The interrupt can be enabled when the port isn't open, typically
* that happens when using one port is open and the other closed (stale
* interrupt) or when one port is used as a console.
*/
if (!ZS_IS_OPEN(uap)) {
pmz_debug("pmz: draining input\n");
/* Port is closed, drain input data */
for (;;) {
if ((++loops) > 1000)
goto flood;
(void)read_zsreg(uap, R1);
write_zsreg(uap, R0, ERR_RES);
(void)read_zsdata(uap);
ch = read_zsreg(uap, R0);
if (!(ch & Rx_CH_AV))
break;
}
return NULL;
}
/* Sanity check, make sure the old bug is no longer happening */
if (uap->port.info == NULL || uap->port.info->tty == NULL) {
WARN_ON(1);
(void)read_zsdata(uap);
return NULL;
}
tty = uap->port.info->tty;
while (1) {
error = 0;
drop = 0;
r1 = read_zsreg(uap, R1);
ch = read_zsdata(uap);
if (r1 & (PAR_ERR | Rx_OVR | CRC_ERR)) {
write_zsreg(uap, R0, ERR_RES);
zssync(uap);
}
ch &= uap->parity_mask;
if (ch == 0 && uap->flags & PMACZILOG_FLAG_BREAK) {
uap->flags &= ~PMACZILOG_FLAG_BREAK;
}
#if defined(CONFIG_MAGIC_SYSRQ) && defined(CONFIG_SERIAL_CORE_CONSOLE)
#ifdef USE_CTRL_O_SYSRQ
/* Handle the SysRq ^O Hack */
if (ch == '\x0f') {
uap->port.sysrq = jiffies + HZ*5;
goto next_char;
}
#endif /* USE_CTRL_O_SYSRQ */
if (uap->port.sysrq) {
int swallow;
spin_unlock(&uap->port.lock);
swallow = uart_handle_sysrq_char(&uap->port, ch);
spin_lock(&uap->port.lock);
if (swallow)
goto next_char;
}
#endif /* CONFIG_MAGIC_SYSRQ && CONFIG_SERIAL_CORE_CONSOLE */
/* A real serial line, record the character and status. */
if (drop)
goto next_char;
flag = TTY_NORMAL;
uap->port.icount.rx++;
if (r1 & (PAR_ERR | Rx_OVR | CRC_ERR | BRK_ABRT)) {
error = 1;
if (r1 & BRK_ABRT) {
pmz_debug("pmz: got break !\n");
r1 &= ~(PAR_ERR | CRC_ERR);
uap->port.icount.brk++;
if (uart_handle_break(&uap->port))
goto next_char;
}
else if (r1 & PAR_ERR)
uap->port.icount.parity++;
else if (r1 & CRC_ERR)
uap->port.icount.frame++;
if (r1 & Rx_OVR)
uap->port.icount.overrun++;
r1 &= uap->port.read_status_mask;
if (r1 & BRK_ABRT)
flag = TTY_BREAK;
else if (r1 & PAR_ERR)
flag = TTY_PARITY;
else if (r1 & CRC_ERR)
flag = TTY_FRAME;
}
if (uap->port.ignore_status_mask == 0xff ||
(r1 & uap->port.ignore_status_mask) == 0) {
tty_insert_flip_char(tty, ch, flag);
}
if (r1 & Rx_OVR)
tty_insert_flip_char(tty, 0, TTY_OVERRUN);
next_char:
/* We can get stuck in an infinite loop getting char 0 when the
* line is in a wrong HW state, we break that here.
* When that happens, I disable the receive side of the driver.
* Note that what I've been experiencing is a real irq loop where
* I'm getting flooded regardless of the actual port speed.
* Something stange is going on with the HW
*/
if ((++loops) > 1000)
goto flood;
ch = read_zsreg(uap, R0);
if (!(ch & Rx_CH_AV))
break;
}
return tty;
flood:
uap->curregs[R1] &= ~(EXT_INT_ENAB | TxINT_ENAB | RxINT_MASK);
write_zsreg(uap, R1, uap->curregs[R1]);
zssync(uap);
dev_err(&uap->dev->ofdev.dev, "pmz: rx irq flood !\n");
return tty;
}
static int pmz_resume(struct macio_dev *mdev)
{
struct uart_pmac_port *uap = dev_get_drvdata(&mdev->ofdev.dev);
struct uart_state *state;
unsigned long flags;
int pwr_delay = 0;
if (uap == NULL)
return 0;
if (mdev->ofdev.dev.power.power_state.event == PM_EVENT_ON)
return 0;
pmz_debug("resume, switching to state 0\n");
state = pmz_uart_reg.state + uap->port.line;
mutex_lock(&pmz_irq_mutex);
mutex_lock(&state->mutex);
spin_lock_irqsave(&uap->port.lock, flags);
if (!ZS_IS_OPEN(uap) && !ZS_IS_CONS(uap)) {
spin_unlock_irqrestore(&uap->port.lock, flags);
goto bail;
}
pwr_delay = __pmz_startup(uap);
/* Take care of config that may have changed while asleep */
__pmz_set_termios(&uap->port, &uap->termios_cache, NULL);
if (ZS_IS_OPEN(uap)) {
/* Enable interrupts */
uap->curregs[R1] |= INT_ALL_Rx | TxINT_ENAB;
if (!ZS_IS_EXTCLK(uap))
uap->curregs[R1] |= EXT_INT_ENAB;
write_zsreg(uap, R1, uap->curregs[R1]);
}
spin_unlock_irqrestore(&uap->port.lock, flags);
if (ZS_IS_CONS(uap))
uap->port.cons->flags |= CON_ENABLED;
/* Re-enable IRQ on the controller */
if (ZS_IS_OPEN(uap) && !ZS_IS_IRQ_ON(pmz_get_port_A(uap))) {
pmz_get_port_A(uap)->flags |= PMACZILOG_FLAG_IS_IRQ_ON;
enable_irq(uap->port.irq);
}
bail:
mutex_unlock(&state->mutex);
mutex_unlock(&pmz_irq_mutex);
/* Right now, we deal with delay by blocking here, I'll be
* smarter later on
*/
if (pwr_delay != 0) {
pmz_debug("pmz: delaying %d ms\n", pwr_delay);
msleep(pwr_delay);
}
pmz_debug("resume, switching complete\n");
mdev->ofdev.dev.power.power_state.event = PM_EVENT_ON;
return 0;
}
static struct tty_struct *pmz_receive_chars(struct uart_pmac_port *uap,
struct pt_regs *regs)
{
struct tty_struct *tty = NULL;
unsigned char ch, r1, drop, error;
int loops = 0;
retry:
/* The interrupt can be enabled when the port isn't open, typically
* that happens when using one port is open and the other closed (stale
* interrupt) or when one port is used as a console.
*/
if (!ZS_IS_OPEN(uap)) {
pmz_debug("pmz: draining input\n");
/* Port is closed, drain input data */
for (;;) {
if ((++loops) > 1000)
goto flood;
(void)read_zsreg(uap, R1);
write_zsreg(uap, R0, ERR_RES);
(void)read_zsdata(uap);
ch = read_zsreg(uap, R0);
if (!(ch & Rx_CH_AV))
break;
}
return NULL;
}
/* Sanity check, make sure the old bug is no longer happening */
if (uap->port.info == NULL || uap->port.info->tty == NULL) {
WARN_ON(1);
(void)read_zsdata(uap);
return NULL;
}
tty = uap->port.info->tty;
while (1) {
error = 0;
drop = 0;
if (unlikely(tty->flip.count >= TTY_FLIPBUF_SIZE)) {
/* Have to drop the lock here */
pmz_debug("pmz: flip overflow\n");
spin_unlock(&uap->port.lock);
tty->flip.work.func((void *)tty);
spin_lock(&uap->port.lock);
if (tty->flip.count >= TTY_FLIPBUF_SIZE)
drop = 1;
if (ZS_IS_ASLEEP(uap))
return NULL;
if (!ZS_IS_OPEN(uap))
goto retry;
}
r1 = read_zsreg(uap, R1);
ch = read_zsdata(uap);
if (r1 & (PAR_ERR | Rx_OVR | CRC_ERR)) {
write_zsreg(uap, R0, ERR_RES);
zssync(uap);
}
ch &= uap->parity_mask;
if (ch == 0 && uap->prev_status & BRK_ABRT)
r1 |= BRK_ABRT;
/* A real serial line, record the character and status. */
if (drop)
goto next_char;
*tty->flip.char_buf_ptr = ch;
*tty->flip.flag_buf_ptr = TTY_NORMAL;
uap->port.icount.rx++;
if (r1 & (PAR_ERR | Rx_OVR | CRC_ERR | BRK_ABRT)) {
error = 1;
if (r1 & BRK_ABRT) {
pmz_debug("pmz: got break !\n");
r1 &= ~(PAR_ERR | CRC_ERR);
uap->port.icount.brk++;
if (uart_handle_break(&uap->port)) {
pmz_debug("pmz: do handle break !\n");
goto next_char;
}
}
else if (r1 & PAR_ERR)
uap->port.icount.parity++;
else if (r1 & CRC_ERR)
uap->port.icount.frame++;
if (r1 & Rx_OVR)
uap->port.icount.overrun++;
r1 &= uap->port.read_status_mask;
if (r1 & BRK_ABRT)
*tty->flip.flag_buf_ptr = TTY_BREAK;
else if (r1 & PAR_ERR)
*tty->flip.flag_buf_ptr = TTY_PARITY;
else if (r1 & CRC_ERR)
*tty->flip.flag_buf_ptr = TTY_FRAME;
}
if (uart_handle_sysrq_char(&uap->port, ch, regs)) {
pmz_debug("pmz: sysrq swallowed the char\n");
goto next_char;
}
if (uap->port.ignore_status_mask == 0xff ||
(r1 & uap->port.ignore_status_mask) == 0) {
tty->flip.flag_buf_ptr++;
tty->flip.char_buf_ptr++;
tty->flip.count++;
}
if ((r1 & Rx_OVR) &&
tty->flip.count < TTY_FLIPBUF_SIZE) {
*tty->flip.flag_buf_ptr = TTY_OVERRUN;
tty->flip.flag_buf_ptr++;
tty->flip.char_buf_ptr++;
tty->flip.count++;
}
next_char:
/* We can get stuck in an infinite loop getting char 0 when the
* line is in a wrong HW state, we break that here.
* When that happens, I disable the receive side of the driver.
* Note that what I've been experiencing is a real irq loop where
* I'm getting flooded regardless of the actual port speed.
* Something stange is going on with the HW
*/
if ((++loops) > 1000)
goto flood;
ch = read_zsreg(uap, R0);
if (!(ch & Rx_CH_AV))
break;
}
return tty;
flood:
uap->curregs[R1] &= ~(EXT_INT_ENAB | TxINT_ENAB | RxINT_MASK);
write_zsreg(uap, R1, uap->curregs[R1]);
zssync(uap);
dev_err(&uap->dev->ofdev.dev, "pmz: rx irq flood !\n");
return tty;
}
