From f17141fdd407de78379222dd59d6f161437db4c8 Mon Sep 17 00:00:00 2001 From: Alan Cox Date: Fri, 26 Aug 2011 11:28:11 +0100 Subject: [PATCH] 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 Tested-by: Michael Lauer Signed-off-by: Greg Kroah-Hartman --- drivers/tty/n_gsm.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c index ed429082304..8d7766bfef8 100644 --- a/drivers/tty/n_gsm.c +++ b/drivers/tty/n_gsm.c @@ -2003,6 +2003,7 @@ void gsm_cleanup_mux(struct gsm_mux *gsm) int i; struct gsm_dlci *dlci = gsm->dlci[0]; struct gsm_msg *txq; + struct gsm_control *gc; gsm->dead = 1; @@ -2016,6 +2017,13 @@ void gsm_cleanup_mux(struct gsm_mux *gsm) 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) { -- 2.46.0