tty: rework break handling

Some hardware needs to do break handling itself and may have partial
support only. Make break_ctl return an error code. Add a tty driver flag
so you can indicate driver hardware side break support.

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 4 insertions, 3 deletions

diff --git a/drivers/char/synclink.c b/drivers/char/synclink.c
index 527d220aa4aa..ef6706f09061 100644
--- a/drivers/char/synclink.c
+++ b/drivers/char/synclink.c
@@ -2897,9 +2897,9 @@ static int tiocmset(struct tty_struct *tty, struct file *file,
  *
  * Arguments:           tty             pointer to tty instance data
  *                      break_state     -1=set break condition, 0=clear
- * Return Value:        None
+ * Return Value:        error code
  */
-static void mgsl_break(struct tty_struct *tty, int break_state)
+static int mgsl_break(struct tty_struct *tty, int break_state)
 {
         struct mgsl_struct * info = (struct mgsl_struct *)tty->driver_data;
         unsigned long flags;
@@ -2909,7 +2909,7 @@ static void mgsl_break(struct tty_struct *tty, int break_state)
                          __FILE__,__LINE__, info->device_name, break_state);
                          
         if (mgsl_paranoia_check(info, tty->name, "mgsl_break"))
-                return;
+                return -EINVAL;
 
         spin_lock_irqsave(&info->irq_spinlock,flags);
         if (break_state == -1)
@@ -2917,6 +2917,7 @@ static void mgsl_break(struct tty_struct *tty, int break_state)
         else 
                 usc_OutReg(info,IOCR,(u16)(usc_InReg(info,IOCR) & ~BIT7));
         spin_unlock_irqrestore(&info->irq_spinlock,flags);
+        return 0;
         
 }       /* end of mgsl_break() */