tty_port: Add a port level carrier detect operation
This is the first step to generalising the various pieces of waiting logic
duplicated in all sorts of serial drivers.
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/char/stallion.c b/drivers/char/stallion.c
index 963b03f..12aecdaf 100644
--- a/drivers/char/stallion.c
+++ b/drivers/char/stallion.c
@@ -130,6 +130,8 @@
static DEFINE_MUTEX(stl_brdslock);
static struct stlbrd *stl_brds[STL_MAXBRDS];
+static const struct tty_port_operations stl_port_ops;
+
/*
* Per board state flags. Used with the state field of the board struct.
* Not really much here!
@@ -786,6 +788,12 @@
/*****************************************************************************/
+static int stl_carrier_raised(struct tty_port *port)
+{
+ struct stlport *portp = container_of(port, struct stlport, port);
+ return (portp->sigs & TIOCM_CD) ? 1 : 0;
+}
+
/*
* Possibly need to wait for carrier (DCD signal) to come high. Say
* maybe because if we are clocal then we don't need to wait...
@@ -796,6 +804,7 @@
{
unsigned long flags;
int rc, doclocal;
+ struct tty_port *port = &portp->port;
pr_debug("stl_waitcarrier(portp=%p,filp=%p)\n", portp, filp);
@@ -809,32 +818,32 @@
portp->openwaitcnt++;
if (! tty_hung_up_p(filp))
- portp->port.count--;
+ port->count--;
for (;;) {
/* Takes brd_lock internally */
stl_setsignals(portp, 1, 1);
if (tty_hung_up_p(filp) ||
- ((portp->port.flags & ASYNC_INITIALIZED) == 0)) {
- if (portp->port.flags & ASYNC_HUP_NOTIFY)
+ ((port->flags & ASYNC_INITIALIZED) == 0)) {
+ if (port->flags & ASYNC_HUP_NOTIFY)
rc = -EBUSY;
else
rc = -ERESTARTSYS;
break;
}
- if (((portp->port.flags & ASYNC_CLOSING) == 0) &&
- (doclocal || (portp->sigs & TIOCM_CD)))
+ if (((port->flags & ASYNC_CLOSING) == 0) &&
+ (doclocal || tty_port_carrier_raised(port)))
break;
if (signal_pending(current)) {
rc = -ERESTARTSYS;
break;
}
/* FIXME */
- interruptible_sleep_on(&portp->port.open_wait);
+ interruptible_sleep_on(&port->open_wait);
}
if (! tty_hung_up_p(filp))
- portp->port.count++;
+ port->count++;
portp->openwaitcnt--;
spin_unlock_irqrestore(&stallion_lock, flags);
@@ -1776,6 +1785,7 @@
break;
}
tty_port_init(&portp->port);
+ portp->port.ops = &stl_port_ops;
portp->magic = STL_PORTMAGIC;
portp->portnr = i;
portp->brdnr = panelp->brdnr;
@@ -2659,6 +2669,10 @@
.tiocmset = stl_tiocmset,
};
+static const struct tty_port_operations stl_port_ops = {
+ .carrier_raised = stl_carrier_raised,
+};
+
/*****************************************************************************/
/* CD1400 HARDWARE FUNCTIONS */
/*****************************************************************************/