From: Daniel Starke <daniel.starke@xxxxxxxxxxx> Add an enumeration for the gsm mux encoding types to improve code readability and to avoid invalid values. Only two values are defined by the standard: - basic option mode - advanced option mode (uses ISO HDLC standard transparency mechanism) Signed-off-by: Daniel Starke <daniel.starke@xxxxxxxxxxx> --- drivers/tty/n_gsm.c | 30 +++++++++++++++++------------- 1 file changed, 17 insertions(+), 13 deletions(-) Incorporated review comments from Jiri Slaby since v2: - removed exlicit cast from enum to int - removed unrelated removal of redundant assignment of gsm->encoding in gsmld_open() Link: https://lore.kernel.org/all/3801995e-1eb5-1184-a9ba-2cec1d19bc58@xxxxxxxxxx/ diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c index caa5c14ed57f..3fa859a29317 100644 --- a/drivers/tty/n_gsm.c +++ b/drivers/tty/n_gsm.c @@ -184,6 +184,11 @@ struct gsm_control { int error; /* Error if any */ }; +enum gsm_encoding { + GSM_BASIC_OPT, + GSM_ADV_OPT, +}; + enum gsm_mux_state { GSM_SEARCH, GSM_START, @@ -230,7 +235,7 @@ struct gsm_mux { unsigned int address; unsigned int count; bool escape; - int encoding; + enum gsm_encoding encoding; u8 control; u8 fcs; u8 *txframe; /* TX framing buffer */ @@ -694,7 +699,7 @@ static int gsm_send(struct gsm_mux *gsm, int addr, int cr, int control) *dp++ = (addr << 2) | (ocr << 1) | EA; *dp++ = control; - if (gsm->encoding == 0) + if (gsm->encoding == GSM_BASIC_OPT) *dp++ = EA; /* Length of data = 0 */ *dp = 0xFF - gsm_fcs_add_block(INIT_FCS, msg->data, dp - msg->data); @@ -813,7 +818,7 @@ static int gsm_send_packet(struct gsm_mux *gsm, struct gsm_msg *msg) int len, ret; - if (gsm->encoding == 0) { + if (gsm->encoding == GSM_BASIC_OPT) { gsm->txframe[0] = GSM0_SOF; memcpy(gsm->txframe + 1, msg->data, msg->len); gsm->txframe[msg->len + 1] = GSM0_SOF; @@ -965,7 +970,7 @@ static void __gsm_data_queue(struct gsm_dlci *dlci, struct gsm_msg *msg) u8 *fcs = dp + msg->len; /* Fill in the header */ - if (gsm->encoding == 0) { + if (gsm->encoding == GSM_BASIC_OPT) { if (msg->len < 128) *--dp = (msg->len << 1) | EA; else { @@ -2508,7 +2513,7 @@ static int gsm_activate_mux(struct gsm_mux *gsm) spin_lock_init(&gsm->control_lock); spin_lock_init(&gsm->tx_lock); - if (gsm->encoding == 0) + if (gsm->encoding == GSM_BASIC_OPT) gsm->receive = gsm0_receive; else gsm->receive = gsm1_receive; @@ -2618,7 +2623,7 @@ static struct gsm_mux *gsm_alloc_mux(void) gsm->n2 = N2; gsm->ftype = UIH; gsm->adaption = 1; - gsm->encoding = 1; + gsm->encoding = GSM_ADV_OPT; gsm->mru = 64; /* Default to encoding 1 so these should be 64 */ gsm->mtu = 64; gsm->dead = true; /* Avoid early tty opens */ @@ -2719,7 +2724,7 @@ static int gsm_config(struct gsm_mux *gsm, struct gsm_config *c) gsm->initiator = c->initiator; gsm->mru = c->mru; gsm->mtu = c->mtu; - gsm->encoding = c->encapsulation; + gsm->encoding = c->encapsulation ? GSM_ADV_OPT : GSM_BASIC_OPT; gsm->adaption = c->adaption; gsm->n2 = c->n2; @@ -2942,8 +2947,7 @@ static int gsmld_open(struct tty_struct *tty) tty->receive_room = 65536; /* Attach the initial passive connection */ - gsm->encoding = 1; - + gsm->encoding = GSM_ADV_OPT; gsmld_attach_gsm(tty, gsm); timer_setup(&gsm->kick_timer, gsm_kick_timer, 0); @@ -3345,7 +3349,7 @@ static int gsm_modem_upd_via_msc(struct gsm_dlci *dlci, u8 brk) struct gsm_control *ctrl; int len = 2; - if (dlci->gsm->encoding != 0) + if (dlci->gsm->encoding != GSM_BASIC_OPT) return 0; modembits[0] = (dlci->addr << 2) | 2 | EA; /* DLCI, Valid, EA */ @@ -3374,7 +3378,7 @@ static int gsm_modem_update(struct gsm_dlci *dlci, u8 brk) /* Send convergence layer type 2 empty data frame. */ gsm_modem_upd_via_data(dlci, brk); return 0; - } else if (dlci->gsm->encoding == 0) { + } else if (dlci->gsm->encoding == GSM_BASIC_OPT) { /* Send as MSC control message. */ return gsm_modem_upd_via_msc(dlci, brk); } @@ -3398,8 +3402,8 @@ static int gsm_carrier_raised(struct tty_port *port) * Basic mode with control channel in ADM mode may not respond * to CMD_MSC at all and modem_rx is empty. */ - if (gsm->encoding == 0 && gsm->dlci[0]->mode == DLCI_MODE_ADM && - !dlci->modem_rx) + if (gsm->encoding == GSM_BASIC_OPT && + gsm->dlci[0]->mode == DLCI_MODE_ADM && !dlci->modem_rx) return 1; return dlci->modem_rx & TIOCM_CD; -- 2.34.1