[PATCH] tty: n_gsm: Fix CR bit value when initiator=0

From: Zhenguo Zhao <zhenguo6858@gmail.com>
To: zhenguo6858@gmail.com, gregkh@linuxfoundation.org, jirislaby@kernel.org
Cc: linux-kernel@vger.kernel.org
Subject: [PATCH]        tty: n_gsm: Fix CR bit value when initiator=0
Date: Wed, 16 Jun 2021 10:56:39 +0800	[thread overview]
Message-ID: <1623812199-31866-1-git-send-email-zhenguo6858@gmail.com> (raw)

From: Zhenguo Zhao <zhenguo.zhao1@unisoc.com>

	When set initiator=0,switch to Responder,gsmld received dlci SABM/DISC
	frame,CR bit should be 0 by calculation.

	receive DLC0 SABM CMD:
	[69.740263] c1 gsmld_receive: 00000000: f9 03 3f 01 1c f9
	[69.893247] c1 gsm_queue cr:1
	[69.897629] c1 <-- 0) C: SABM(P)
	[69.907516] c1 gsm_queue cr:0

Signed-off-by: Zhenguo Zhao <zhenguo.zhao1@unisoc.com>
---
 drivers/tty/n_gsm.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c
index 5fea02c..becca2c 100644
--- a/drivers/tty/n_gsm.c
+++ b/drivers/tty/n_gsm.c
@@ -1779,7 +1779,7 @@ static void gsm_queue(struct gsm_mux *gsm)
 
 	switch (gsm->control) {
 	case SABM|PF:
-		if (cr == 0)
+		if (cr == 1)
 			goto invalid;
 		if (dlci == NULL)
 			dlci = gsm_dlci_alloc(gsm, address);
@@ -1793,7 +1793,7 @@ static void gsm_queue(struct gsm_mux *gsm)
 		}
 		break;
 	case DISC|PF:
-		if (cr == 0)
+		if (cr == 1)
 			goto invalid;
 		if (dlci == NULL || dlci->state == DLCI_CLOSED) {
 			gsm_response(gsm, address, DM);
-- 
1.9.1

