host/trxcon/l1ctl.c: share primitive management code

This change introduces shared primitive management functions,
exposed from the l1ctl_rx_data_req() implementation:

  - sched_trx_init_prim() - allocates memory for a new primitive
    and its payload. Initializes primitive's header, setting
    the logical channel type and the payload length. After
    initialization, the talloc context of a primitive is
    a trx instance, which passed as the first argument.

  - sched_trx_push_prim() - decodes the timeslot index from
    chan_nr and pushes a primitive to its transimt queue.
    The talloc context of primitive is changed to the
    parent trx_ts instance after queuing.

Both functions will be used for handling both L1CTL_TRAFFIC_REQ
and L1CTL_RACH_REQ.

Change-Id: I8169a1ef4ef54d91b50f3e213e4842f54af8b499

3 files changed, 90 insertions, 44 deletions

diff --git a/src/host/trxcon/l1ctl.c b/src/host/trxcon/l1ctl.c
index f193a7a5..f125948d 100644
--- a/src/host/trxcon/l1ctl.c
+++ b/src/host/trxcon/l1ctl.c
@@ -589,17 +589,13 @@ static int l1ctl_rx_dm_rel_req(struct l1ctl_link *l1l, struct msgb *msg)
 
 static int l1ctl_rx_data_req(struct l1ctl_link *l1l, struct msgb *msg)
 {
-	struct trx_ts *ts;
-	struct trx_ts_prim *prim;
 	struct l1ctl_info_ul *ul;
-	struct l1ctl_data_ind *data_ind;
-	enum trx_lchan_type lchan_type;
-	uint8_t chan_nr, link_id, tn;
-	size_t len;
-	int rc = 0;
+	struct trx_ts_prim *prim;
+	uint8_t chan_nr, link_id;
+	int rc;
 
+	/* Extract UL frame header */
 	ul = (struct l1ctl_info_ul *) msg->l1h;
-	data_ind = (struct l1ctl_data_ind *) ul->payload;
 
 	/* Obtain channel description */
 	chan_nr = ul->chan_nr;
@@ -608,48 +604,21 @@ static int l1ctl_rx_data_req(struct l1ctl_link *l1l, struct msgb *msg)
 	LOGP(DL1D, LOGL_DEBUG, "Recv Data Req (chan_nr=0x%02x, "
 		"link_id=0x%02x)\n", chan_nr, link_id);
 
-	/* Determine TS index */
-	tn = chan_nr & 0x7;
-	if (tn > 7) {
-		LOGP(DL1D, LOGL_ERROR, "Incorrect TS index %u\n", tn);
-		rc = -EINVAL;
+	/* Init a new primitive */
+	rc = sched_trx_init_prim(l1l->trx, &prim, 23,
+		chan_nr, link_id);
+	if (rc)
 		goto exit;
-	}
 
-	/* Determine lchan type */
-	lchan_type = sched_trx_chan_nr2lchan_type(chan_nr, link_id);
-	if (!lchan_type) {
-		LOGP(DL1D, LOGL_ERROR, "Couldn't determine lchan type "
-			"for chan_nr=%02x and link_id=%02x\n", chan_nr, link_id);
-		rc = -EINVAL;
-		goto exit;
-	}
-
-	/* Check whether required timeslot is allocated and configured */
-	ts = l1l->trx->ts_list[tn];
-	if (ts == NULL || ts->mf_layout == NULL) {
-		LOGP(DL1D, LOGL_ERROR, "Timeslot %u isn't configured\n", tn);
-		rc = -EINVAL;
-		goto exit;
-	}
-
-	/* Allocate a new primitive */
-	len = sizeof(struct trx_ts_prim) + sizeof(struct l1ctl_info_ul) + 23;
-	prim = talloc_zero_size(ts, len);
-	if (prim == NULL) {
-		LOGP(DL1D, LOGL_ERROR, "Failed to allocate memory\n");
-		rc = -ENOMEM;
+	/* Push this primitive to transmit queue */
+	rc = sched_trx_push_prim(l1l->trx, prim, chan_nr);
+	if (rc) {
+		talloc_free(prim);
 		goto exit;
 	}
 
-	/* Set logical channel of primitive */
-	prim->chan = lchan_type;
-
 	/* Fill in the payload */
-	memcpy(prim->payload, data_ind, 23);
-
-	/* Add to TS queue */
-	llist_add_tail(&prim->list, &ts->tx_prims);
+	memcpy(prim->payload, ul->payload, 23);
 
 exit:
 	msgb_free(msg);
diff --git a/src/host/trxcon/sched_trx.c b/src/host/trxcon/sched_trx.c
index 956c261b..7f6729cb 100644
--- a/src/host/trxcon/sched_trx.c
+++ b/src/host/trxcon/sched_trx.c
@@ -417,6 +417,75 @@ void sched_trx_deactivate_all_lchans(struct trx_ts *ts)
 	}
 }
 
+int sched_trx_init_prim(struct trx_instance *trx,
+	struct trx_ts_prim **prim, size_t pl_len,
+	uint8_t chan_nr, uint8_t link_id)
+{
+	enum trx_lchan_type lchan_type;
+	struct trx_ts_prim *new_prim;
+	uint8_t len;
+
+	/* Determine lchan type */
+	lchan_type = sched_trx_chan_nr2lchan_type(chan_nr, link_id);
+	if (!lchan_type) {
+		LOGP(DSCH, LOGL_ERROR, "Couldn't determine lchan type "
+			"for chan_nr=%02x and link_id=%02x\n", chan_nr, link_id);
+		return -EINVAL;
+	}
+
+	/* How much memory do we need? */
+	len  = sizeof(struct trx_ts_prim); /* Primitive header */
+	len += pl_len; /* Requested payload size */
+
+	/* Allocate a new primitive */
+	new_prim = talloc_zero_size(trx, len);
+	if (new_prim == NULL) {
+		LOGP(DSCH, LOGL_ERROR, "Failed to allocate memory\n");
+		return -ENOMEM;
+	}
+
+	/* Init primitive header */
+	new_prim->payload_len = pl_len;
+	new_prim->chan = lchan_type;
+
+	/* Set external pointer */
+	*prim = new_prim;
+
+	return 0;
+}
+
+int sched_trx_push_prim(struct trx_instance *trx,
+	struct trx_ts_prim *prim, uint8_t chan_nr)
+{
+	struct trx_ts *ts;
+	uint8_t tn;
+
+	/* Determine TS index */
+	tn = chan_nr & 0x7;
+	if (tn > 7) {
+		LOGP(DSCH, LOGL_ERROR, "Incorrect TS index %u\n", tn);
+		return -EINVAL;
+	}
+
+	/* Check whether required timeslot is allocated and configured */
+	ts = trx->ts_list[tn];
+	if (ts == NULL || ts->mf_layout == NULL) {
+		LOGP(DSCH, LOGL_ERROR, "Timeslot %u isn't configured\n", tn);
+		return -EINVAL;
+	}
+
+	/**
+	 * Change talloc context of primitive
+	 * from trx to the parent ts
+	 */
+	talloc_steal(ts, prim);
+
+	/* Add primitive to TS transmit queue */
+	llist_add_tail(&prim->list, &ts->tx_prims);
+
+	return 0;
+}
+
 enum gsm_phys_chan_config sched_trx_chan_nr2pchan_config(uint8_t chan_nr)
 {
 	uint8_t cbits = chan_nr >> 3;
diff --git a/src/host/trxcon/sched_trx.h b/src/host/trxcon/sched_trx.h
index 1b74041c..4209f533 100644
--- a/src/host/trxcon/sched_trx.h
+++ b/src/host/trxcon/sched_trx.h
@@ -235,6 +235,8 @@ struct trx_ts_prim {
 	struct llist_head list;
 	/*! \brief Logical channel type */
 	enum trx_lchan_type chan;
+	/*! \brief Payload length */
+	size_t payload_len;
 	/*! \brief Payload */
 	uint8_t payload[0];
 };
@@ -267,5 +269,11 @@ int sched_trx_deactivate_lchan(struct trx_ts *ts, enum trx_lchan_type chan);
 struct trx_lchan_state *sched_trx_find_lchan(struct trx_ts *ts,
 	enum trx_lchan_type chan);
 
+/* Primitive management functions */
+int sched_trx_init_prim(struct trx_instance *trx, struct trx_ts_prim **prim,
+	size_t pl_len, uint8_t chan_nr, uint8_t link_id);
+int sched_trx_push_prim(struct trx_instance *trx,
+	struct trx_ts_prim *prim, uint8_t chan_nr);
+
 int sched_trx_handle_rx_burst(struct trx_instance *trx, uint8_t tn,
 	uint32_t burst_fn, sbit_t *bits, uint16_t nbits, int8_t rssi, float toa);