[PATCH] Fix CTS handling in pmac-zilog.c

From: Paul Mackerras <paulus@samba.org>

This patch fixes a bug in the pmac-zilog driver where if you enable
CRTSCTS mode, it won't output data when CTS is asserted.  On
powermacs, the CTS input is inverted.  It also fixes a logic bug in
testing for CTS and DCD changes.

diff --git a/drivers/serial/pmac_zilog.c b/drivers/serial/pmac_zilog.c
index 67854b129203f35f97533fcb904bf7b89634bbd1..5df209699de041d7c41e689cebfd38ae62ecc864 100644 (file)
--- a/drivers/serial/pmac_zilog.c
+++ b/drivers/serial/pmac_zilog.c
@@ -352,13 +352,14 @@ static void pmz_status_handle(struct uart_pmac_port *uap, struct pt_regs *regs)
                /* The Zilog just gives us an interrupt when DCD/CTS/etc. change.
                 * But it does not tell us which bit has changed, we have to keep
                 * track of this ourselves.
+                * The CTS input is inverted for some reason.  -- paulus
                 */
-               if ((status & DCD) ^ uap->prev_status)
+               if ((status ^ uap->prev_status) & DCD)
                        uart_handle_dcd_change(&uap->port,
                                               (status & DCD));
-               if ((status & CTS) ^ uap->prev_status)
+               if ((status ^ uap->prev_status) & CTS)
                        uart_handle_cts_change(&uap->port,
-                                              (status & CTS));
+                                              !(status & CTS));
 
                wake_up_interruptible(&uap->port.info->delta_msr_wait);
        }
@@ -595,7 +596,7 @@ static unsigned int pmz_get_mctrl(struct uart_port *port)
                ret |= TIOCM_CAR;
        if (status & SYNC_HUNT)
                ret |= TIOCM_DSR;
-       if (status & CTS)
+       if (!(status & CTS))
                ret |= TIOCM_CTS;
 
        return ret;