From: Gregory CLEMENT Date: Tue, 12 May 2020 11:53:22 +0000 (+0200) Subject: tty: n_gsm: Fix SOF skipping X-Git-Tag: v5.15~3665^2~37 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=84d6f81c1fb58b56eba81ff0a36cf31946064b40;p=platform%2Fkernel%2Flinux-starfive.git tty: n_gsm: Fix SOF skipping For at least some modems like the TELIT LE910, skipping SOF makes transfers blocking indefinitely after a short amount of data transferred. Given the small improvement provided by skipping the SOF (just one byte on about 100 bytes), it seems better to completely remove this "feature" than make it optional. Fixes: e1eaea46bb40 ("tty: n_gsm line discipline") Signed-off-by: Gregory CLEMENT Link: https://lore.kernel.org/r/20200512115323.1447922-3-gregory.clement@bootlin.com Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c index 67c8f81..d8d1966 100644 --- a/drivers/tty/n_gsm.c +++ b/drivers/tty/n_gsm.c @@ -667,7 +667,6 @@ static void gsm_data_kick(struct gsm_mux *gsm) { struct gsm_msg *msg, *nmsg; int len; - int skip_sof = 0; list_for_each_entry_safe(msg, nmsg, &gsm->tx_list, list) { if (gsm->constipated && msg->addr) @@ -689,15 +688,10 @@ static void gsm_data_kick(struct gsm_mux *gsm) print_hex_dump_bytes("gsm_data_kick: ", DUMP_PREFIX_OFFSET, gsm->txframe, len); - - if (gsm->output(gsm, gsm->txframe + skip_sof, - len - skip_sof) < 0) + if (gsm->output(gsm, gsm->txframe, len) < 0) break; /* FIXME: Can eliminate one SOF in many more cases */ gsm->tx_bytes -= msg->len; - /* For a burst of frames skip the extra SOF within the - burst */ - skip_sof = 1; list_del(&msg->list); kfree(msg);