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, 13 insertions, 6 deletions

diff --git a/drivers/char/isicom.c b/drivers/char/isicom.c
index a59eac584d16..4d745a89504f 100644
--- a/drivers/char/isicom.c
+++ b/drivers/char/isicom.c
@@ -329,7 +329,7 @@ static inline void drop_rts(struct isi_port *port)
 
 /* card->lock MUST NOT be held */
 
-static void isicom_raise_dtr_rts(struct tty_port *port)
+static void isicom_dtr_rts(struct tty_port *port, int on)
 {
         struct isi_port *ip = container_of(port, struct isi_port, port);
         struct isi_board *card = ip->card;
@@ -339,10 +339,17 @@ static void isicom_raise_dtr_rts(struct tty_port *port)
         if (!lock_card(card))
                 return;
 
-        outw(0x8000 | (channel << card->shift_count) | 0x02, base);
-        outw(0x0f04, base);
-        InterruptTheCard(base);
-        ip->status |= (ISI_DTR | ISI_RTS);
+        if (on) {
+                outw(0x8000 | (channel << card->shift_count) | 0x02, base);
+                outw(0x0f04, base);
+                InterruptTheCard(base);
+                ip->status |= (ISI_DTR | ISI_RTS);
+        } else {
+                outw(0x8000 | (channel << card->shift_count) | 0x02, base);
+                outw(0x0C04, base);
+                InterruptTheCard(base);
+                ip->status &= ~(ISI_DTR | ISI_RTS);
+        }
         unlock_card(card);
 }
 
@@ -1339,7 +1346,7 @@ static const struct tty_operations isicom_ops = {
 
 static const struct tty_port_operations isicom_port_ops = {
         .carrier_raised         = isicom_carrier_raised,
-        .raise_dtr_rts          = isicom_raise_dtr_rts,
+        .dtr_rts                = isicom_dtr_rts,
 };
 
 static int __devinit reset_card(struct pci_dev *pdev,