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authorDmitry Torokhov <dmitry.torokhov@gmail.com>2015-02-10 11:35:36 -0800
committerDmitry Torokhov <dmitry.torokhov@gmail.com>2015-02-10 11:35:36 -0800
commit4ba24fef3eb3b142197135223b90ced2f319cd53 (patch)
treea20c125b27740ec7b4c761b11d801108e1b316b2 /drivers/tty/serial/serial_core.c
parent47c1ffb2b6b630894e9a16442611c056ab21c057 (diff)
parent98a4a59ee31a12105a2b84f5b8b515ac2cb208ef (diff)
Merge branch 'next' into for-linus
Prepare first round of input updates for 3.20.
Diffstat (limited to 'drivers/tty/serial/serial_core.c')
-rw-r--r--drivers/tty/serial/serial_core.c251
1 files changed, 155 insertions, 96 deletions
diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c
index 29a7be47389..57ca61b1467 100644
--- a/drivers/tty/serial/serial_core.c
+++ b/drivers/tty/serial/serial_core.c
@@ -59,6 +59,11 @@ static void uart_change_pm(struct uart_state *state,
static void uart_port_shutdown(struct tty_port *port);
+static int uart_dcd_enabled(struct uart_port *uport)
+{
+ return !!(uport->status & UPSTAT_DCD_ENABLE);
+}
+
/*
* This routine is used by the interrupt handler to schedule processing in
* the software interrupt portion of the driver.
@@ -90,7 +95,7 @@ static void __uart_start(struct tty_struct *tty)
struct uart_state *state = tty->driver_data;
struct uart_port *port = state->uart_port;
- if (!tty->stopped && !tty->hw_stopped)
+ if (!uart_tx_stopped(port))
port->ops->start_tx(port);
}
@@ -130,7 +135,6 @@ static int uart_port_startup(struct tty_struct *tty, struct uart_state *state,
int init_hw)
{
struct uart_port *uport = state->uart_port;
- struct tty_port *port = &state->port;
unsigned long page;
int retval = 0;
@@ -175,17 +179,14 @@ static int uart_port_startup(struct tty_struct *tty, struct uart_state *state,
if (tty->termios.c_cflag & CBAUD)
uart_set_mctrl(uport, TIOCM_RTS | TIOCM_DTR);
}
- /*
- * if hw support flow control without software intervention,
- * then skip the below check
- */
- if (tty_port_cts_enabled(port) &&
- !(uport->flags & UPF_HARD_FLOW)) {
- spin_lock_irq(&uport->lock);
- if (!(uport->ops->get_mctrl(uport) & TIOCM_CTS))
- tty->hw_stopped = 1;
- spin_unlock_irq(&uport->lock);
- }
+
+ spin_lock_irq(&uport->lock);
+ if (uart_cts_enabled(uport) &&
+ !(uport->ops->get_mctrl(uport) & TIOCM_CTS))
+ uport->hw_stopped = 1;
+ else
+ uport->hw_stopped = 0;
+ spin_unlock_irq(&uport->lock);
}
/*
@@ -362,7 +363,7 @@ uart_get_baud_rate(struct uart_port *port, struct ktermios *termios,
* The spd_hi, spd_vhi, spd_shi, spd_warp kludge...
* Die! Die! Die!
*/
- if (baud == 38400)
+ if (try == 0 && baud == 38400)
baud = altbaud;
/*
@@ -435,11 +436,10 @@ uart_get_divisor(struct uart_port *port, unsigned int baud)
EXPORT_SYMBOL(uart_get_divisor);
-/* FIXME: Consistent locking policy */
+/* Caller holds port mutex */
static void uart_change_speed(struct tty_struct *tty, struct uart_state *state,
struct ktermios *old_termios)
{
- struct tty_port *port = &state->port;
struct uart_port *uport = state->uart_port;
struct ktermios *termios;
@@ -454,17 +454,19 @@ static void uart_change_speed(struct tty_struct *tty, struct uart_state *state,
uport->ops->set_termios(uport, termios, old_termios);
/*
- * Set flags based on termios cflag
+ * Set modem status enables based on termios cflag
*/
+ spin_lock_irq(&uport->lock);
if (termios->c_cflag & CRTSCTS)
- set_bit(ASYNCB_CTS_FLOW, &port->flags);
+ uport->status |= UPSTAT_CTS_ENABLE;
else
- clear_bit(ASYNCB_CTS_FLOW, &port->flags);
+ uport->status &= ~UPSTAT_CTS_ENABLE;
if (termios->c_cflag & CLOCAL)
- clear_bit(ASYNCB_CHECK_CD, &port->flags);
+ uport->status &= ~UPSTAT_DCD_ENABLE;
else
- set_bit(ASYNCB_CHECK_CD, &port->flags);
+ uport->status |= UPSTAT_DCD_ENABLE;
+ spin_unlock_irq(&uport->lock);
}
static inline int __uart_put_char(struct uart_port *port,
@@ -535,9 +537,10 @@ static int uart_write(struct tty_struct *tty,
count -= c;
ret += c;
}
+
+ __uart_start(tty);
spin_unlock_irqrestore(&port->lock, flags);
- uart_start(tty);
return ret;
}
@@ -604,12 +607,11 @@ static void uart_send_xchar(struct tty_struct *tty, char ch)
if (port->ops->send_xchar)
port->ops->send_xchar(port, ch);
else {
+ spin_lock_irqsave(&port->lock, flags);
port->x_char = ch;
- if (ch) {
- spin_lock_irqsave(&port->lock, flags);
+ if (ch)
port->ops->start_tx(port);
- spin_unlock_irqrestore(&port->lock, flags);
- }
+ spin_unlock_irqrestore(&port->lock, flags);
}
}
@@ -617,7 +619,7 @@ static void uart_throttle(struct tty_struct *tty)
{
struct uart_state *state = tty->driver_data;
struct uart_port *port = state->uart_port;
- uint32_t mask = 0;
+ upf_t mask = 0;
if (I_IXOFF(tty))
mask |= UPF_SOFT_FLOW;
@@ -640,7 +642,7 @@ static void uart_unthrottle(struct tty_struct *tty)
{
struct uart_state *state = tty->driver_data;
struct uart_port *port = state->uart_port;
- uint32_t mask = 0;
+ upf_t mask = 0;
if (I_IXOFF(tty))
mask |= UPF_SOFT_FLOW;
@@ -652,12 +654,8 @@ static void uart_unthrottle(struct tty_struct *tty)
mask &= ~port->flags;
}
- if (mask & UPF_SOFT_FLOW) {
- if (port->x_char)
- port->x_char = 0;
- else
- uart_send_xchar(tty, START_CHAR(tty));
- }
+ if (mask & UPF_SOFT_FLOW)
+ uart_send_xchar(tty, START_CHAR(tty));
if (mask & UPF_HARD_FLOW)
uart_set_mctrl(port, TIOCM_RTS);
@@ -892,10 +890,11 @@ static int uart_set_info(struct tty_struct *tty, struct tty_port *port,
*/
if (uport->flags & UPF_SPD_MASK) {
char buf[64];
- printk(KERN_NOTICE
- "%s sets custom speed on %s. This "
- "is deprecated.\n", current->comm,
- tty_name(port->tty, buf));
+
+ dev_notice(uport->dev,
+ "%s sets custom speed on %s. This is deprecated.\n",
+ current->comm,
+ tty_name(port->tty, buf));
}
uart_change_speed(tty, state, NULL);
}
@@ -952,7 +951,7 @@ static int uart_get_lsr_info(struct tty_struct *tty,
*/
if (uport->x_char ||
((uart_circ_chars_pending(&state->xmit) > 0) &&
- !tty->stopped && !tty->hw_stopped))
+ !uart_tx_stopped(uport)))
result &= ~TIOCSER_TEMT;
return put_user(result, value);
@@ -1153,6 +1152,47 @@ static int uart_get_icount(struct tty_struct *tty,
return 0;
}
+static int uart_get_rs485_config(struct uart_port *port,
+ struct serial_rs485 __user *rs485)
+{
+ unsigned long flags;
+ struct serial_rs485 aux;
+
+ spin_lock_irqsave(&port->lock, flags);
+ aux = port->rs485;
+ spin_unlock_irqrestore(&port->lock, flags);
+
+ if (copy_to_user(rs485, &aux, sizeof(aux)))
+ return -EFAULT;
+
+ return 0;
+}
+
+static int uart_set_rs485_config(struct uart_port *port,
+ struct serial_rs485 __user *rs485_user)
+{
+ struct serial_rs485 rs485;
+ int ret;
+ unsigned long flags;
+
+ if (!port->rs485_config)
+ return -ENOIOCTLCMD;
+
+ if (copy_from_user(&rs485, rs485_user, sizeof(*rs485_user)))
+ return -EFAULT;
+
+ spin_lock_irqsave(&port->lock, flags);
+ ret = port->rs485_config(port, &rs485);
+ spin_unlock_irqrestore(&port->lock, flags);
+ if (ret)
+ return ret;
+
+ if (copy_to_user(rs485_user, &port->rs485, sizeof(port->rs485)))
+ return -EFAULT;
+
+ return 0;
+}
+
/*
* Called via sys_ioctl. We can use spin_lock_irq() here.
*/
@@ -1175,11 +1215,15 @@ uart_ioctl(struct tty_struct *tty, unsigned int cmd,
break;
case TIOCSSERIAL:
+ down_write(&tty->termios_rwsem);
ret = uart_set_info_user(tty, state, uarg);
+ up_write(&tty->termios_rwsem);
break;
case TIOCSERCONFIG:
+ down_write(&tty->termios_rwsem);
ret = uart_do_autoconfig(tty, state);
+ up_write(&tty->termios_rwsem);
break;
case TIOCSERGWILD: /* obsolete */
@@ -1219,11 +1263,19 @@ uart_ioctl(struct tty_struct *tty, unsigned int cmd,
* All these rely on hardware being present and need to be
* protected against the tty being hung up.
*/
+
switch (cmd) {
case TIOCSERGETLSR: /* Get line status register */
ret = uart_get_lsr_info(tty, state, uarg);
break;
+ case TIOCGRS485:
+ ret = uart_get_rs485_config(state->uart_port, uarg);
+ break;
+
+ case TIOCSRS485:
+ ret = uart_set_rs485_config(state->uart_port, uarg);
+ break;
default: {
struct uart_port *uport = state->uart_port;
if (uport->ops->ioctl)
@@ -1242,8 +1294,11 @@ static void uart_set_ldisc(struct tty_struct *tty)
struct uart_state *state = tty->driver_data;
struct uart_port *uport = state->uart_port;
- if (uport->ops->set_ldisc)
- uport->ops->set_ldisc(uport, tty->termios.c_line);
+ if (uport->ops->set_ldisc) {
+ mutex_lock(&state->port.mutex);
+ uport->ops->set_ldisc(uport, &tty->termios);
+ mutex_unlock(&state->port.mutex);
+ }
}
static void uart_set_termios(struct tty_struct *tty,
@@ -1251,7 +1306,6 @@ static void uart_set_termios(struct tty_struct *tty,
{
struct uart_state *state = tty->driver_data;
struct uart_port *uport = state->uart_port;
- unsigned long flags;
unsigned int cflag = tty->termios.c_cflag;
unsigned int iflag_mask = IGNBRK|BRKINT|IGNPAR|PARMRK|INPCK;
bool sw_changed = false;
@@ -1281,7 +1335,9 @@ static void uart_set_termios(struct tty_struct *tty,
return;
}
+ mutex_lock(&state->port.mutex);
uart_change_speed(tty, state, old_termios);
+ mutex_unlock(&state->port.mutex);
/* reload cflag from termios; port driver may have overriden flags */
cflag = tty->termios.c_cflag;
@@ -1291,34 +1347,33 @@ static void uart_set_termios(struct tty_struct *tty,
/* Handle transition away from B0 status */
else if (!(old_termios->c_cflag & CBAUD) && (cflag & CBAUD)) {
unsigned int mask = TIOCM_DTR;
- if (!(cflag & CRTSCTS) ||
- !test_bit(TTY_THROTTLED, &tty->flags))
+ if (!(cflag & CRTSCTS) || !test_bit(TTY_THROTTLED, &tty->flags))
mask |= TIOCM_RTS;
uart_set_mctrl(uport, mask);
}
/*
* If the port is doing h/w assisted flow control, do nothing.
- * We assume that tty->hw_stopped has never been set.
+ * We assume that port->hw_stopped has never been set.
*/
if (uport->flags & UPF_HARD_FLOW)
return;
/* Handle turning off CRTSCTS */
if ((old_termios->c_cflag & CRTSCTS) && !(cflag & CRTSCTS)) {
- spin_lock_irqsave(&uport->lock, flags);
- tty->hw_stopped = 0;
+ spin_lock_irq(&uport->lock);
+ uport->hw_stopped = 0;
__uart_start(tty);
- spin_unlock_irqrestore(&uport->lock, flags);
+ spin_unlock_irq(&uport->lock);
}
/* Handle turning on CRTSCTS */
else if (!(old_termios->c_cflag & CRTSCTS) && (cflag & CRTSCTS)) {
- spin_lock_irqsave(&uport->lock, flags);
+ spin_lock_irq(&uport->lock);
if (!(uport->ops->get_mctrl(uport) & TIOCM_CTS)) {
- tty->hw_stopped = 1;
+ uport->hw_stopped = 1;
uport->ops->stop_tx(uport);
}
- spin_unlock_irqrestore(&uport->lock, flags);
+ spin_unlock_irq(&uport->lock);
}
}
@@ -1335,8 +1390,16 @@ static void uart_close(struct tty_struct *tty, struct file *filp)
struct uart_port *uport;
unsigned long flags;
- if (!state)
+ if (!state) {
+ struct uart_driver *drv = tty->driver->driver_state;
+
+ state = drv->state + tty->index;
+ port = &state->port;
+ spin_lock_irq(&port->lock);
+ --port->count;
+ spin_unlock_irq(&port->lock);
return;
+ }
uport = state->uart_port;
port = &state->port;
@@ -1365,10 +1428,6 @@ static void uart_close(struct tty_struct *tty, struct file *filp)
mutex_lock(&port->mutex);
uart_shutdown(tty, state);
- uart_flush_buffer(tty);
-
- tty_ldisc_flush(tty);
-
tty_port_tty_set(port, NULL);
tty->closing = 0;
spin_lock_irqsave(&port->lock, flags);
@@ -1376,8 +1435,7 @@ static void uart_close(struct tty_struct *tty, struct file *filp)
if (port->blocked_open) {
spin_unlock_irqrestore(&port->lock, flags);
if (port->close_delay)
- msleep_interruptible(
- jiffies_to_msecs(port->close_delay));
+ msleep_interruptible(jiffies_to_msecs(port->close_delay));
spin_lock_irqsave(&port->lock, flags);
} else if (!uart_console(uport)) {
spin_unlock_irqrestore(&port->lock, flags);
@@ -1395,6 +1453,8 @@ static void uart_close(struct tty_struct *tty, struct file *filp)
wake_up_interruptible(&port->close_wait);
mutex_unlock(&port->mutex);
+
+ tty_ldisc_flush(tty);
}
static void uart_wait_until_sent(struct tty_struct *tty, int timeout)
@@ -1556,6 +1616,10 @@ static int uart_open(struct tty_struct *tty, struct file *filp)
pr_debug("uart_open(%d) called\n", line);
+ spin_lock_irq(&port->lock);
+ ++port->count;
+ spin_unlock_irq(&port->lock);
+
/*
* We take the semaphore here to guarantee that we won't be re-entered
* while allocating the state structure, or while we request any IRQs
@@ -1568,17 +1632,11 @@ static int uart_open(struct tty_struct *tty, struct file *filp)
goto end;
}
- port->count++;
if (!state->uart_port || state->uart_port->flags & UPF_DEAD) {
retval = -ENXIO;
- goto err_dec_count;
+ goto err_unlock;
}
- /*
- * Once we set tty->driver_data here, we are guaranteed that
- * uart_close() will decrement the driver module use count.
- * Any failures from here onwards should not touch the count.
- */
tty->driver_data = state;
state->uart_port->state = state;
state->port.low_latency =
@@ -1599,8 +1657,7 @@ static int uart_open(struct tty_struct *tty, struct file *filp)
end:
return retval;
-err_dec_count:
- port->count--;
+err_unlock:
mutex_unlock(&port->mutex);
goto end;
}
@@ -1975,12 +2032,9 @@ int uart_suspend_port(struct uart_driver *drv, struct uart_port *uport)
for (tries = 3; !ops->tx_empty(uport) && tries; tries--)
msleep(10);
if (!tries)
- printk(KERN_ERR "%s%s%s%d: Unable to drain "
- "transmitter\n",
- uport->dev ? dev_name(uport->dev) : "",
- uport->dev ? ": " : "",
- drv->dev_name,
- drv->tty_driver->name_base + uport->line);
+ dev_err(uport->dev, "%s%d: Unable to drain transmitter\n",
+ drv->dev_name,
+ drv->tty_driver->name_base + uport->line);
if (console_suspend_enabled || !uart_console(uport))
ops->shutdown(uport);
@@ -2099,6 +2153,7 @@ uart_report_port(struct uart_driver *drv, struct uart_port *port)
break;
case UPIO_MEM:
case UPIO_MEM32:
+ case UPIO_MEM32BE:
case UPIO_AU:
case UPIO_TSI:
snprintf(address, sizeof(address),
@@ -2109,9 +2164,7 @@ uart_report_port(struct uart_driver *drv, struct uart_port *port)
break;
}
- printk(KERN_INFO "%s%s%s%d at %s (irq = %d, base_baud = %d) is a %s\n",
- port->dev ? dev_name(port->dev) : "",
- port->dev ? ": " : "",
+ dev_info(port->dev, "%s%d at %s (irq = %d, base_baud = %d) is a %s\n",
drv->dev_name,
drv->tty_driver->name_base + port->line,
address, port->irq, port->uartclk / 16, uart_type(port));
@@ -2348,8 +2401,6 @@ int uart_register_driver(struct uart_driver *drv)
tty_port_init(port);
port->ops = &uart_port_ops;
- port->close_delay = HZ / 2; /* .5 seconds */
- port->closing_wait = 30 * HZ;/* 30 seconds */
}
retval = tty_register_driver(normal);
@@ -2598,11 +2649,12 @@ int uart_add_one_port(struct uart_driver *drv, struct uart_port *uport)
goto out;
}
+ /* Link the port to the driver state table and vice versa */
state->uart_port = uport;
- state->pm_state = UART_PM_STATE_UNDEFINED;
+ uport->state = state;
+ state->pm_state = UART_PM_STATE_UNDEFINED;
uport->cons = drv->cons;
- uport->state = state;
/*
* If this port is a console, then the spinlock is already
@@ -2640,7 +2692,7 @@ int uart_add_one_port(struct uart_driver *drv, struct uart_port *uport)
if (likely(!IS_ERR(tty_dev))) {
device_set_wakeup_capable(tty_dev, 1);
} else {
- printk(KERN_ERR "Cannot register tty device on line %d\n",
+ dev_err(uport->dev, "Cannot register tty device on line %d\n",
uport->line);
}
@@ -2675,7 +2727,7 @@ int uart_remove_one_port(struct uart_driver *drv, struct uart_port *uport)
BUG_ON(in_interrupt());
if (state->uart_port != uport)
- printk(KERN_ALERT "Removing wrong port: %p != %p\n",
+ dev_alert(uport->dev, "Removing wrong port: %p != %p\n",
state->uart_port, uport);
mutex_lock(&port_mutex);
@@ -2745,6 +2797,7 @@ int uart_match_port(struct uart_port *port1, struct uart_port *port2)
(port1->hub6 == port2->hub6);
case UPIO_MEM:
case UPIO_MEM32:
+ case UPIO_MEM32BE:
case UPIO_AU:
case UPIO_TSI:
return (port1->mapbase == port2->mapbase);
@@ -2757,22 +2810,29 @@ EXPORT_SYMBOL(uart_match_port);
* uart_handle_dcd_change - handle a change of carrier detect state
* @uport: uart_port structure for the open port
* @status: new carrier detect status, nonzero if active
+ *
+ * Caller must hold uport->lock
*/
void uart_handle_dcd_change(struct uart_port *uport, unsigned int status)
{
struct tty_port *port = &uport->state->port;
struct tty_struct *tty = port->tty;
- struct tty_ldisc *ld = tty ? tty_ldisc_ref(tty) : NULL;
+ struct tty_ldisc *ld;
+
+ lockdep_assert_held_once(&uport->lock);
- if (ld) {
- if (ld->ops->dcd_change)
- ld->ops->dcd_change(tty, status);
- tty_ldisc_deref(ld);
+ if (tty) {
+ ld = tty_ldisc_ref(tty);
+ if (ld) {
+ if (ld->ops->dcd_change)
+ ld->ops->dcd_change(tty, status);
+ tty_ldisc_deref(ld);
+ }
}
uport->icount.dcd++;
- if (port->flags & ASYNC_CHECK_CD) {
+ if (uart_dcd_enabled(uport)) {
if (status)
wake_up_interruptible(&port->open_wait);
else if (tty)
@@ -2785,26 +2845,25 @@ EXPORT_SYMBOL_GPL(uart_handle_dcd_change);
* uart_handle_cts_change - handle a change of clear-to-send state
* @uport: uart_port structure for the open port
* @status: new clear to send status, nonzero if active
+ *
+ * Caller must hold uport->lock
*/
void uart_handle_cts_change(struct uart_port *uport, unsigned int status)
{
- struct tty_port *port = &uport->state->port;
- struct tty_struct *tty = port->tty;
+ lockdep_assert_held_once(&uport->lock);
uport->icount.cts++;
- /* skip below code if the hw flow control is supported */
- if (tty_port_cts_enabled(port) &&
- !(uport->flags & UPF_HARD_FLOW)) {
- if (tty->hw_stopped) {
+ if (uart_cts_enabled(uport)) {
+ if (uport->hw_stopped) {
if (status) {
- tty->hw_stopped = 0;
+ uport->hw_stopped = 0;
uport->ops->start_tx(uport);
uart_write_wakeup(uport);
}
} else {
if (!status) {
- tty->hw_stopped = 1;
+ uport->hw_stopped = 1;
uport->ops->stop_tx(uport);
}
}