Commit 48473802 authored by Daniel Starke's avatar Daniel Starke Committed by Greg Kroah-Hartman
Browse files

tty: n_gsm: fix missing update of modem controls after DLCI open 



Currently the peer is not informed about the initial state of the modem
control lines after a new DLCI has been opened.
Fix this by sending the initial modem control line states after DLCI open.

Fixes: e1eaea46 ("tty: n_gsm line discipline")
Cc: stable@vger.kernel.org
Signed-off-by: default avatarDaniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20220420101346.3315-1-daniel.starke@siemens.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent cc994bb9

drivers/tty/n_gsm.c

+4 −0
Original line number Diff line number Diff line
@@ -370,6 +370,7 @@ static const u8 gsm_fcs8[256] = { 
#define GOOD_FCS	0xCF



static int gsmld_output(struct gsm_mux *gsm, u8 *data, int len);

static int gsmtty_modem_update(struct gsm_dlci *dlci, u8 brk);



/**

 *	gsm_fcs_add	-	update FCS
@@ -1483,6 +1484,9 @@ static void gsm_dlci_open(struct gsm_dlci *dlci) 
		pr_debug("DLCI %d goes open.\n", dlci->addr);

	/* Register gsmtty driver,report gsmtty dev add uevent for user */

	tty_register_device(gsm_tty_driver, dlci->addr, NULL);

	/* Send current modem state */

	if (dlci->addr)

		gsmtty_modem_update(dlci, 0);

	wake_up(&dlci->gsm->event);

}