From 8482bcd58530ad5857d7187854132f2b846db681 Mon Sep 17 00:00:00 2001 From: Alan Cox Date: Mon, 30 Nov 2009 13:18:13 +0000 Subject: [PATCH] tty: moxa: Fix modem op locking This is overkill and mostly not needed Signed-off-by: Alan Cox Signed-off-by: Greg Kroah-Hartman --- drivers/char/moxa.c | 25 ++++++++++--------------- 1 file changed, 10 insertions(+), 15 deletions(-) diff --git a/drivers/char/moxa.c b/drivers/char/moxa.c index d180aa965a5a..ac06d0131db5 100644 --- a/drivers/char/moxa.c +++ b/drivers/char/moxa.c @@ -139,7 +139,7 @@ struct moxa_port { int cflag; unsigned long statusflags; - u8 DCDState; + u8 DCDState; /* Protected by the port lock */ u8 lineCtrl; u8 lowChkFlag; }; @@ -1141,9 +1141,9 @@ static int moxa_carrier_raised(struct tty_port *port) struct moxa_port *ch = container_of(port, struct moxa_port, port); int dcd; - spin_lock_bh(&moxa_lock); + spin_lock_irq(&port->lock); dcd = ch->DCDState; - spin_unlock_bh(&moxa_lock); + spin_unlock_irq(&port->lock); return dcd; } @@ -1267,16 +1267,9 @@ static int moxa_chars_in_buffer(struct tty_struct *tty) static int moxa_tiocmget(struct tty_struct *tty, struct file *file) { - struct moxa_port *ch; + struct moxa_port *ch = tty->driver_data; int flag = 0, dtr, rts; - mutex_lock(&moxa_openlock); - ch = tty->driver_data; - if (!ch) { - mutex_unlock(&moxa_openlock); - return -EINVAL; - } - MoxaPortGetLineOut(ch, &dtr, &rts); if (dtr) flag |= TIOCM_DTR; @@ -1289,7 +1282,6 @@ static int moxa_tiocmget(struct tty_struct *tty, struct file *file) flag |= TIOCM_DSR; if (dtr & 4) flag |= TIOCM_CD; - mutex_unlock(&moxa_openlock); return flag; } @@ -1368,15 +1360,20 @@ static void moxa_hangup(struct tty_struct *tty) static void moxa_new_dcdstate(struct moxa_port *p, u8 dcd) { struct tty_struct *tty; + unsigned long flags; dcd = !!dcd; + spin_lock_irqsave(&p->port.lock, flags); if (dcd != p->DCDState) { + p->DCDState = dcd; + spin_unlock_irqrestore(&p->port.lock, flags); tty = tty_port_tty_get(&p->port); if (tty && C_CLOCAL(tty) && !dcd) tty_hangup(tty); tty_kref_put(tty); } - p->DCDState = dcd; + else + spin_unlock_irqrestore(&p->port.lock, flags); } static int moxa_poll_port(struct moxa_port *p, unsigned int handle, @@ -1878,9 +1875,7 @@ static int MoxaPortLineStatus(struct moxa_port *port) val &= 0x0B; if (val & 8) val |= 4; - spin_lock_bh(&moxa_lock); moxa_new_dcdstate(port, val & 8); - spin_unlock_bh(&moxa_lock); val &= 7; return val; } -- 2.20.1