diff options
| -rw-r--r-- | src/gsm/lapdm.c | 23 |
1 files changed, 21 insertions, 2 deletions
diff --git a/src/gsm/lapdm.c b/src/gsm/lapdm.c index e5fbaf0d..fa928c5e 100644 --- a/src/gsm/lapdm.c +++ b/src/gsm/lapdm.c @@ -380,7 +380,21 @@ static int tx_ph_data_enqueue(struct lapdm_datalink *dl, struct msgb *msg, return le->l1_prim_cb(&pp.oph, le->l1_ctx); } -static struct msgb *tx_dequeue_msgb(struct lapdm_entity *le) +/* Dequeue a Downlink message for DCCH (dedicated channel) */ +static struct msgb *tx_dequeue_dcch_msgb(struct lapdm_entity *le) +{ + struct msgb *msg; + + /* SAPI=0 always has higher priority than SAPI=3 */ + msg = msgb_dequeue(&le->datalink[DL_SAPI0].dl.tx_queue); + if (msg == NULL) /* no SAPI=0 messages, dequeue SAPI=3 (if any) */ + msg = msgb_dequeue(&le->datalink[DL_SAPI3].dl.tx_queue); + + return msg; +} + +/* Dequeue a Downlink message for ACCH (associated channel) */ +static struct msgb *tx_dequeue_acch_msgb(struct lapdm_entity *le) { struct lapdm_datalink *dl; int last = le->last_tx_dequeue; @@ -411,7 +425,12 @@ int lapdm_phsap_dequeue_prim(struct lapdm_entity *le, struct osmo_phsap_prim *pp struct msgb *msg; uint8_t pad; - msg = tx_dequeue_msgb(le); + /* Dequeue depending on channel type: DCCH or ACCH. + * See 3GPP TS 44.005, section 4.2.2 "Priority". */ + if (le == &le->lapdm_ch->lapdm_dcch) + msg = tx_dequeue_dcch_msgb(le); + else + msg = tx_dequeue_acch_msgb(le); if (!msg) return -ENODEV; |