staging/fwserial: Only reset port status for attached peers

When a port has been reserved in an attempt to connect to a peer
but that attempt does not succeed, releasing the port should not
reset the port line status. Although resetting is functionally
harmless, it can appear as if a remote peer dropped carrier to a
port it was not attached to (which can be confusing).

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 12 insertions, 9 deletions

diff --git a/drivers/staging/fwserial/fwserial.c b/drivers/staging/fwserial/fwserial.c
index 59e90e666d7b..8db4b41d4f43 100644
--- a/drivers/staging/fwserial/fwserial.c
+++ b/drivers/staging/fwserial/fwserial.c
@@ -1783,10 +1783,11 @@ static struct fwtty_port *fwserial_find_port(struct fwtty_peer *peer)
         return NULL;
 }
 
-static void fwserial_release_port(struct fwtty_port *port)
+static void fwserial_release_port(struct fwtty_port *port, bool reset)
 {
         /* drop carrier (and all other line status) */
-        fwtty_update_port_status(port, 0);
+        if (reset)
+                fwtty_update_port_status(port, 0);
 
         spin_lock_bh(&port->lock);
 
@@ -1816,7 +1817,7 @@ static void fwserial_plug_timeout(unsigned long data)
         spin_unlock_bh(&peer->lock);
 
         if (port)
-                fwserial_release_port(port);
+                fwserial_release_port(port, false);
 }
 
 /**
@@ -1879,7 +1880,7 @@ cancel_timer:
         peer_revert_state(peer);
 release_port:
         spin_unlock_bh(&peer->lock);
-        fwserial_release_port(port);
+        fwserial_release_port(port, false);
 free_pkt:
         kfree(pkt);
         return err;
@@ -2157,7 +2158,7 @@ static void fwserial_remove_peer(struct fwtty_peer *peer)
         spin_unlock_bh(&peer->lock);
 
         if (port)
-                fwserial_release_port(port);
+                fwserial_release_port(port, true);
 
         synchronize_rcu();
         kfree(peer);
@@ -2617,7 +2618,7 @@ static void fwserial_handle_plug_req(struct work_struct *work)
 
         spin_unlock_bh(&peer->lock);
         if (port)
-                fwserial_release_port(port);
+                fwserial_release_port(port, false);
 
         rcode = fwserial_send_mgmt_sync(peer, pkt);
 
@@ -2639,7 +2640,7 @@ static void fwserial_handle_plug_req(struct work_struct *work)
 cleanup:
         spin_unlock_bh(&peer->lock);
         if (port)
-                fwserial_release_port(port);
+                fwserial_release_port(port, false);
         kfree(pkt);
         return;
 }
@@ -2691,7 +2692,7 @@ static void fwserial_handle_unplug_req(struct work_struct *work)
 cleanup:
         spin_unlock_bh(&peer->lock);
         if (port)
-                fwserial_release_port(port);
+                fwserial_release_port(port, true);
         kfree(pkt);
         return;
 }
@@ -2702,6 +2703,7 @@ static int fwserial_parse_mgmt_write(struct fwtty_peer *peer,
                                      size_t len)
 {
         struct fwtty_port *port = NULL;
+        bool reset = false;
         int rcode;
 
         if (addr != fwserial_mgmt_addr_handler.offset || len < sizeof(pkt->hdr))
@@ -2777,6 +2779,7 @@ static int fwserial_parse_mgmt_write(struct fwtty_peer *peer,
                         if (be16_to_cpu(pkt->hdr.code) & FWSC_RSP_NACK)
                                 fwtty_notice(&peer->unit, "NACK unplug?");
                         port = peer_revert_state(peer);
+                        reset = true;
                 }
                 break;
 
@@ -2788,7 +2791,7 @@ static int fwserial_parse_mgmt_write(struct fwtty_peer *peer,
         spin_unlock_bh(&peer->lock);
 
         if (port)
-                fwserial_release_port(port);
+                fwserial_release_port(port, reset);
 
         return rcode;
 }