Re: [CFT:PATCH] 2/3: Check status of CTS when using flow control

[Gene Heskett <gene.heskett@verizon.net>]

On Sunday 26 June 2005 18:17, Russell King wrote:
>Fix bugme #4712: read the CTS status and set hw_stopped if CTS
>is not active.
>
>Thanks to Stefan Wolff for spotting this problem.
>
This one needs to make mainline & maybe, after 3 years, I can use a 
pl2303 to talk to an old slow coco.  Twould be very nice if that 
fixed the lack of flow controls the connection apparently fails from.

>Index: drivers/serial/serial_core.c
>===================================================================
>--- a/drivers/serial/serial_core.c  (mode:100644)
>+++ b/drivers/serial/serial_core.c  (mode:100644)
>@@ -180,6 +180,13 @@
>     */
>    if (info->tty->termios->c_cflag & CBAUD)
>     uart_set_mctrl(port, TIOCM_RTS | TIOCM_DTR);
>+
>+   if (info->flags & UIF_CTS_FLOW) {
>+    spin_lock_irq(&port->lock);
>+    if (!(port->ops->get_mctrl(port) & TIOCM_CTS))
>+					info->tty->hw_stopped = 1;
>+				spin_unlock_irq(&port->lock);
>+			}
> 		}
>
> 		info->flags |= UIF_INITIALIZED;
>@@ -1134,6 +1141,16 @@
> 		spin_unlock_irqrestore(&state->port->lock, flags);
> 	}
>
>+	/* Handle turning on CRTSCTS */
>+	if (!(old_termios->c_cflag & CRTSCTS) && (cflag & CRTSCTS)) {
>+		spin_lock_irqsave(&state->port->lock, flags);
>+		if (!(state->port->ops->get_mctrl(state->port) & TIOCM_CTS)) {
>+			tty->hw_stopped = 1;
>+			state->port->ops->stop_tx(state->port, 0);
>+		}
>+		spin_unlock_irqrestore(&state->port->lock, flags);
>+	}
>+
> #if 0
> 	/*
> 	 * No need to wake up processes in open wait, since they
>-
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-- 
Cheers, Gene
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
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