sx driver, DCD-HylaFAX problem solved

[Heinz-Ado Arnolds]

Rogier Wolff wrote:
>
...
> Please Email Marcello, Linus and linux-kernel with this patch, and
> state that you are submitting this patch on my request for inclusion
> in the standard kernel.
>
>                         Roger.

Hi Marcelo, hi Linus, hi Alan,

I'm sending you this patch to the specialix sx driver on the request
of Roger E. Wolf. It fixes a long outstanding problem with hangup when
a DCD change is detected by the driver. The CLOCAL in c_cflag was
ignored. The problem shows up in connection with HylaFAX and gettys.

Please insert this patch into the next available kernel releases.
The patch is to linux-2.4.16, but this section of the sx driver
didn't change at least since 2.2.19.

Thanks a lot for your attention.

Ado

-------------------------------------------------------------------------

--- linux/drivers/char/sx.c.~1~	Fri Nov  9 23:01:21 2001
+++ linux/drivers/char/sx.c	Thu Dec 20 17:22:53 2001
@@ -1160,7 +1160,8 @@
 				/* DCD went UP */
 				if( (~(port->gs.flags & ASYNC_NORMAL_ACTIVE) || 
 						 ~(port->gs.flags & ASYNC_CALLOUT_ACTIVE)) &&
-						(sx_read_channel_byte(port, hi_hstat) != HS_IDLE_CLOSED)) {
+						(sx_read_channel_byte(port, hi_hstat) != HS_IDLE_CLOSED) &&
+						!(port->gs.tty->termios->c_cflag & CLOCAL) ) {
 					/* Are we blocking in open?*/
 					sx_dprintk (SX_DEBUG_MODEMSIGNALS, "DCD active, unblocking
open\n");
 					wake_up_interruptible(&port->gs.open_wait);
@@ -1170,7 +1171,8 @@
 			} else {
 				/* DCD went down! */
 				if (!((port->gs.flags & ASYNC_CALLOUT_ACTIVE) &&
-				      (port->gs.flags & ASYNC_CALLOUT_NOHUP))) {
+				      (port->gs.flags & ASYNC_CALLOUT_NOHUP)) &&
+				    !(port->gs.tty->termios->c_cflag & CLOCAL) ) {
 					sx_dprintk (SX_DEBUG_MODEMSIGNALS, "DCD dropped. hanging
up....\n");
 					tty_hangup (port->gs.tty);
 				} else {

-- 
------------------------------------------------------------------------
  Heinz-Ado Arnolds                        [e-mail]
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