TTY layer buffering revamp broke ia64 in commit
 33f0f88f1c51ae5c2d593d26960c760ea154c2e2
  CC      arch/ia64/hp/sim/simserial.o
arch/ia64/hp/sim/simserial.c: In function `receive_chars':
arch/ia64/hp/sim/simserial.c:170: error: structure has no member named `flip'
 ... and so on ...
make[1]: *** [arch/ia64/hp/sim/simserial.o] Error 1
Patch from Andreas Schwab.
Signed-off-by: Tony Luck <tony.luck@intel.com>
                        }
                }
                seen_esc = 0;
-               if (tty->flip.count >= TTY_FLIPBUF_SIZE) break;
 
-               *tty->flip.char_buf_ptr = ch;
-
-               *tty->flip.flag_buf_ptr = 0;
-
-               tty->flip.flag_buf_ptr++;
-               tty->flip.char_buf_ptr++;
-               tty->flip.count++;
+               if (tty_insert_flip_char(tty, ch, TTY_NORMAL) == 0)
+                       break;
        }
        tty_flip_buffer_push(tty);
 }