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path: root/drivers/tty/serial/pmac_zilog.c
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Diffstat (limited to 'drivers/tty/serial/pmac_zilog.c')
-rw-r--r--drivers/tty/serial/pmac_zilog.c69
1 files changed, 41 insertions, 28 deletions
diff --git a/drivers/tty/serial/pmac_zilog.c b/drivers/tty/serial/pmac_zilog.c
index e9c2dfe471a..f7ad5b90305 100644
--- a/drivers/tty/serial/pmac_zilog.c
+++ b/drivers/tty/serial/pmac_zilog.c
@@ -57,6 +57,8 @@
#include <linux/bitops.h>
#include <linux/sysrq.h>
#include <linux/mutex.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
#include <asm/sections.h>
#include <asm/io.h>
#include <asm/irq.h>
@@ -227,19 +229,19 @@ static void pmz_interrupt_control(struct uart_pmac_port *uap, int enable)
write_zsreg(uap, R1, uap->curregs[1]);
}
-static struct tty_struct *pmz_receive_chars(struct uart_pmac_port *uap)
+static bool pmz_receive_chars(struct uart_pmac_port *uap)
{
- struct tty_struct *tty = NULL;
+ struct tty_port *port;
unsigned char ch, r1, drop, error, flag;
int loops = 0;
/* Sanity check, make sure the old bug is no longer happening */
- if (uap->port.state == NULL || uap->port.state->port.tty == NULL) {
+ if (uap->port.state == NULL) {
WARN_ON(1);
(void)read_zsdata(uap);
- return NULL;
+ return false;
}
- tty = uap->port.state->port.tty;
+ port = &uap->port.state->port;
while (1) {
error = 0;
@@ -309,10 +311,10 @@ static struct tty_struct *pmz_receive_chars(struct uart_pmac_port *uap)
if (uap->port.ignore_status_mask == 0xff ||
(r1 & uap->port.ignore_status_mask) == 0) {
- tty_insert_flip_char(tty, ch, flag);
+ tty_insert_flip_char(port, ch, flag);
}
if (r1 & Rx_OVR)
- tty_insert_flip_char(tty, 0, TTY_OVERRUN);
+ tty_insert_flip_char(port, 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.
@@ -328,11 +330,11 @@ static struct tty_struct *pmz_receive_chars(struct uart_pmac_port *uap)
break;
}
- return tty;
+ return true;
flood:
pmz_interrupt_control(uap, 0);
pmz_error("pmz: rx irq flood !\n");
- return tty;
+ return true;
}
static void pmz_status_handle(struct uart_pmac_port *uap)
@@ -453,7 +455,7 @@ static irqreturn_t pmz_interrupt(int irq, void *dev_id)
struct uart_pmac_port *uap_a;
struct uart_pmac_port *uap_b;
int rc = IRQ_NONE;
- struct tty_struct *tty;
+ bool push;
u8 r3;
uap_a = pmz_get_port_A(uap);
@@ -466,10 +468,10 @@ static irqreturn_t pmz_interrupt(int irq, void *dev_id)
pmz_debug("irq, r3: %x\n", r3);
#endif
/* Channel A */
- tty = NULL;
+ push = false;
if (r3 & (CHAEXT | CHATxIP | CHARxIP)) {
if (!ZS_IS_OPEN(uap_a)) {
- pmz_debug("ChanA interrupt while open !\n");
+ pmz_debug("ChanA interrupt while not open !\n");
goto skip_a;
}
write_zsreg(uap_a, R0, RES_H_IUS);
@@ -477,24 +479,24 @@ static irqreturn_t pmz_interrupt(int irq, void *dev_id)
if (r3 & CHAEXT)
pmz_status_handle(uap_a);
if (r3 & CHARxIP)
- tty = pmz_receive_chars(uap_a);
+ push = pmz_receive_chars(uap_a);
if (r3 & CHATxIP)
pmz_transmit_chars(uap_a);
rc = IRQ_HANDLED;
}
skip_a:
spin_unlock(&uap_a->port.lock);
- if (tty != NULL)
- tty_flip_buffer_push(tty);
+ if (push)
+ tty_flip_buffer_push(&uap->port.state->port);
if (!uap_b)
goto out;
spin_lock(&uap_b->port.lock);
- tty = NULL;
+ push = false;
if (r3 & (CHBEXT | CHBTxIP | CHBRxIP)) {
- if (!ZS_IS_OPEN(uap_a)) {
- pmz_debug("ChanB interrupt while open !\n");
+ if (!ZS_IS_OPEN(uap_b)) {
+ pmz_debug("ChanB interrupt while not open !\n");
goto skip_b;
}
write_zsreg(uap_b, R0, RES_H_IUS);
@@ -502,15 +504,15 @@ static irqreturn_t pmz_interrupt(int irq, void *dev_id)
if (r3 & CHBEXT)
pmz_status_handle(uap_b);
if (r3 & CHBRxIP)
- tty = pmz_receive_chars(uap_b);
+ push = pmz_receive_chars(uap_b);
if (r3 & CHBTxIP)
pmz_transmit_chars(uap_b);
rc = IRQ_HANDLED;
}
skip_b:
spin_unlock(&uap_b->port.lock);
- if (tty != NULL)
- tty_flip_buffer_push(tty);
+ if (push)
+ tty_flip_buffer_push(&uap->port.state->port);
out:
return rc;
@@ -651,6 +653,8 @@ static void pmz_start_tx(struct uart_port *port)
} else {
struct circ_buf *xmit = &port->state->xmit;
+ if (uart_circ_empty(xmit))
+ goto out;
write_zsdata(uap, xmit->buf[xmit->tail]);
zssync(uap);
xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
@@ -659,6 +663,7 @@ static void pmz_start_tx(struct uart_port *port)
if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
uart_write_wakeup(&uap->port);
}
+ out:
pmz_debug("pmz: start_tx() done.\n");
}
@@ -1072,7 +1077,7 @@ static void pmz_convert_to_zs(struct uart_pmac_port *uap, unsigned int cflag,
uap->curregs[5] |= Tx8;
uap->parity_mask = 0xff;
break;
- };
+ }
uap->curregs[4] &= ~(SB_MASK);
if (cflag & CSTOPB)
uap->curregs[4] |= SB2;
@@ -1090,7 +1095,7 @@ static void pmz_convert_to_zs(struct uart_pmac_port *uap, unsigned int cflag,
uap->port.read_status_mask = Rx_OVR;
if (iflag & INPCK)
uap->port.read_status_mask |= CRC_ERR | PAR_ERR;
- if (iflag & (BRKINT | PARMRK))
+ if (iflag & (IGNBRK | BRKINT | PARMRK))
uap->port.read_status_mask |= BRK_ABRT;
uap->port.ignore_status_mask = 0;
@@ -1348,10 +1353,16 @@ static int pmz_verify_port(struct uart_port *port, struct serial_struct *ser)
static int pmz_poll_get_char(struct uart_port *port)
{
struct uart_pmac_port *uap = (struct uart_pmac_port *)port;
+ int tries = 2;
- while ((read_zsreg(uap, R0) & Rx_CH_AV) == 0)
- udelay(5);
- return read_zsdata(uap);
+ while (tries) {
+ if ((read_zsreg(uap, R0) & Rx_CH_AV) != 0)
+ return read_zsdata(uap);
+ if (tries--)
+ udelay(5);
+ }
+
+ return NO_POLL_CHAR;
}
static void pmz_poll_put_char(struct uart_port *port, unsigned char c)
@@ -1506,7 +1517,7 @@ no_dma:
* fixed up interrupt info, but we use the device-tree directly
* here due to early probing so we need the fixup too.
*/
- if (uap->port.irq == NO_IRQ &&
+ if (uap->port.irq == 0 &&
np->parent && np->parent->parent &&
of_device_is_compatible(np->parent->parent, "gatwick")) {
/* IRQs on gatwick are offset by 64 */
@@ -1792,7 +1803,6 @@ static int __exit pmz_detach(struct platform_device *pdev)
uart_remove_one_port(&pmz_uart_reg, &uap->port);
- platform_set_drvdata(pdev, NULL);
uap->port.dev = NULL;
return 0;
@@ -2045,6 +2055,9 @@ static int __init pmz_console_init(void)
/* Probe ports */
pmz_probe();
+ if (pmz_ports_count == 0)
+ return -ENODEV;
+
/* TODO: Autoprobe console based on OF */
/* pmz_console.index = i; */
register_console(&pmz_console);