n_gsm: fix UIH control byte : P bit should be 0
* the GSM 07.10 specification says in 5.4.3.1 that
'both stations shall set the P bit to 0'
thanks to Alan Cox for finding this explanation in the spec
* without this fix, on Telit & Sim.com modems, opening a new DLC
randomly fails. Not setting PF bit of the control byte gives a
reliable behaviour on these modems.
Signed-off-by: Eric Bénard <eric@eukrea.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c
index 0d90be4..176f632 100644
--- a/drivers/tty/n_gsm.c
+++ b/drivers/tty/n_gsm.c
@@ -1250,8 +1250,7 @@
static void gsm_control_transmit(struct gsm_mux *gsm, struct gsm_control *ctrl)
{
- struct gsm_msg *msg = gsm_data_alloc(gsm, 0, ctrl->len + 1,
- gsm->ftype|PF);
+ struct gsm_msg *msg = gsm_data_alloc(gsm, 0, ctrl->len + 1, gsm->ftype);
if (msg == NULL)
return;
msg->data[0] = (ctrl->cmd << 1) | 2 | EA; /* command */