tty: Add carrier processing on close to the tty_port core

Some drivers implement this internally, others miss it out. Push the
behaviour into the core code as that way everyone will do it consistently.

Update the dtr rts method to raise or lower depending upon flags. Having a
single method in this style fits most of the implementations more cleanly than
two funtions.

We need this in place before we tackle the USB side

Signed-off-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 9 insertions, 4 deletions

diff --git a/drivers/char/rocket.c b/drivers/char/rocket.c
index f59fc5cea067..7399188049d8 100644
--- a/drivers/char/rocket.c
+++ b/drivers/char/rocket.c
@@ -872,11 +872,16 @@ static int carrier_raised(struct tty_port *port)
         return (sGetChanStatusLo(&info->channel) & CD_ACT) ? 1 : 0;
 }
 
-static void raise_dtr_rts(struct tty_port *port)
+static void dtr_rts(struct tty_port *port, int on)
 {
         struct r_port *info = container_of(port, struct r_port, port);
-        sSetDTR(&info->channel);
-        sSetRTS(&info->channel);
+        if (on) {
+                sSetDTR(&info->channel);
+                sSetRTS(&info->channel);
+        } else {
+                sClrDTR(&info->channel);
+                sClrRTS(&info->channel);
+        }
 }
 
 /*
@@ -2250,7 +2255,7 @@ static const struct tty_operations rocket_ops = {
 
 static const struct tty_port_operations rocket_port_ops = {
         .carrier_raised = carrier_raised,
-        .raise_dtr_rts = raise_dtr_rts,
+        .dtr_rts = dtr_rts,
 };
 
 /*