ser_gigaset: turn nonsense checks into WARN_ON

These checks do nothing useful to protect the code from races. On the
other hand if the old code has been masking a real bug we would like to
know about it.

The check for tiocmset is kept because it is valid for a tty driver to
have a NULL tiocmset method. That in itself is probably a mistake given
modern coding practices - but needs fixing in the tty layer.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Acked-by: Tilman Schmidt <tilman@imap.cc>
Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/isdn/gigaset/ser-gigaset.c b/drivers/isdn/gigaset/ser-gigaset.c
index d8771b5..8e21f6a 100644 (file)
--- a/drivers/isdn/gigaset/ser-gigaset.c
+++ b/drivers/isdn/gigaset/ser-gigaset.c
@@ -67,8 +67,7 @@ static int write_modem(struct cardstate *cs)
        struct sk_buff *skb = bcs->tx_skb;
        int sent = -EOPNOTSUPP;
 
-       if (!tty || !tty->ops || !skb)
-               return -EINVAL;
+       WARN_ON(!tty || !tty->ops || !skb);
 
        if (!skb->len) {
                dev_kfree_skb_any(skb);
@@ -109,8 +108,7 @@ static int send_cb(struct cardstate *cs)
        unsigned long flags;
        int sent = 0;
 
-       if (!tty || !tty->ops)
-               return -EFAULT;
+       WARN_ON(!tty || !tty->ops);
 
        cb = cs->cmdbuf;
        if (!cb)
@@ -432,7 +430,9 @@ static int gigaset_set_modem_ctrl(struct cardstate *cs, unsigned old_state,
        struct tty_struct *tty = cs->hw.ser->tty;
        unsigned int set, clear;
 
-       if (!tty || !tty->ops || !tty->ops->tiocmset)
+       WARN_ON(!tty || !tty->ops);
+       /* tiocmset is an optional tty driver method */
+       if (!tty->ops->tiocmset)
                return -EINVAL;
        set = new_state & ~old_state;
        clear = old_state & ~new_state;