> gsm->received_fcs is not used for GSM1 mode. Thus we put an
> additional byte to CRC calculation. As result we get a wrong CRC
> and reject incoming frame.
That much is true except that it was originally tested with gsm encoding
1 on various modems for a while and not seen the problem. So I am trying
to work out why or whether some of the GSM0 patches broke GSM1 somewhere.
What hardware was it tested on ?
It looks right - probably the code wants pushing into
gsm0_receive/gsm1_receive appropriately so no special cases leak into
gsm_queue.
>
> Signed-off-by: Mikhail Kshevetskiy <mikhail.kshevetskiy@xxxxxxxxx>
> ---
> drivers/tty/n_gsm.c | 8 ++++++--
> 1 files changed, 6 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c
> index 176f632..4806276 100644
> --- a/drivers/tty/n_gsm.c
> +++ b/drivers/tty/n_gsm.c
> @@ -1658,8 +1658,12 @@ static void gsm_queue(struct gsm_mux *gsm)
>
> if ((gsm->control & ~PF) == UI)
> gsm->fcs = gsm_fcs_add_block(gsm->fcs, gsm->buf, gsm->len);
> - /* generate final CRC with received FCS */
> - gsm->fcs = gsm_fcs_add(gsm->fcs, gsm->received_fcs);
> + if (gsm->encoding == 0){
> + /* WARNING: gsm->received_fcs is used for gsm->encoding = 0 only.
> + In this case it contain the last piece of data
> + required to generate final CRC */
> + gsm->fcs = gsm_fcs_add(gsm->fcs, gsm->received_fcs);
> + }
> if (gsm->fcs != GOOD_FCS) {
> gsm->bad_fcs++;
> if (debug & 4)
--
--
"Alan, I'm getting a bit worried about you."
-- Linus Torvalds
--
To unsubscribe from this list: send the line "unsubscribe linux-serial" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
