[PATCH v2] tty: n_gsm: delete SABM command frame as requester

[Zhenguo Zhao]

From: Zhenguo Zhao <Zhenguo.Zhao1@xxxxxxxxxx>

as initiator,it need to send SABM command ,as requester,there is
no need to send the SABM control frame,it will cause redundant data.

Signed-off-by: Zhenguo Zhao <Zhenguo.Zhao1@xxxxxxxxxx>
---
 drivers/tty/n_gsm.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c
index 5fea02c..41a6501 100644
--- a/drivers/tty/n_gsm.c
+++ b/drivers/tty/n_gsm.c
@@ -2997,6 +2997,7 @@ static int gsmtty_open(struct tty_struct *tty, struct file *filp)
 {
 	struct gsm_dlci *dlci = tty->driver_data;
 	struct tty_port *port = &dlci->port;
+	struct gsm_mux *gsm = dlci->gsm;
 
 	port->count++;
 	tty_port_tty_set(port, tty);
@@ -3005,8 +3006,9 @@ static int gsmtty_open(struct tty_struct *tty, struct file *filp)
 	/* We could in theory open and close before we wait - eg if we get
 	   a DM straight back. This is ok as that will have caused a hangup */
 	tty_port_set_initialized(port, 1);
-	/* Start sending off SABM messages */
-	gsm_dlci_begin_open(dlci);
+	/* Start sending off SABM messages for initiator */
+	if (gsm->initiator)
+		gsm_dlci_begin_open(dlci);
 	/* And wait for virtual carrier */
 	return tty_port_block_til_ready(port, tty, filp);
 }
-- 
1.9.1