n_gsm: Send CLD command on exit
A DISC on DLCI 0 should close down the mux but Michael Lauer reports this
is not the case for some modems. Send a CLD as well.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Tested-by: Michael Lauer
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c
index ed42908..8d7766b 100644
--- a/drivers/tty/n_gsm.c
+++ b/drivers/tty/n_gsm.c
@@ -2003,6 +2003,7 @@
int i;
struct gsm_dlci *dlci = gsm->dlci[0];
struct gsm_msg *txq;
+ struct gsm_control *gc;
gsm->dead = 1;
@@ -2016,6 +2017,13 @@
spin_unlock(&gsm_mux_lock);
WARN_ON(i == MAX_MUX);
+ /* In theory disconnecting DLCI 0 is sufficient but for some
+ modems this is apparently not the case. */
+ if (dlci) {
+ gc = gsm_control_send(gsm, CMD_CLD, NULL, 0);
+ if (gc)
+ gsm_control_wait(gsm, gc);
+ }
del_timer_sync(&gsm->t2_timer);
/* Now we are sure T2 has stopped */
if (dlci) {