net: l2: ieee802154: simplify/fix ACK procedure

Removes redundant ACK state from `struct ieee802154_context` and simplifies the ACK procedure. Signed-off-by: Florian Grandel <fgrandel@code-for-humans.de>
zephyrproject-rtos · Jul 6, 2023 · 3724f46 · 3724f46
1 parent a7612f7
commit 3724f46
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Showing 3 changed files with 17 additions and 14 deletions.
diff --git a/include/zephyr/net/ieee802154.h b/include/zephyr/net/ieee802154.h
@@ -156,9 +156,8 @@ struct ieee802154_context {
  */
  uint8_t sequence;
 
- uint8_t _unused : 6;
+ uint8_t _unused : 7;
 
- uint8_t ack_received : 1; /* guarded by ack_lock */
  uint8_t ack_requested : 1; /* guarded by ack_lock */
  uint8_t ack_seq; /* guarded by ack_lock */
  struct k_sem ack_lock;

diff --git a/subsys/net/l2/ieee802154/ieee802154.c b/subsys/net/l2/ieee802154/ieee802154.c
@@ -110,8 +110,9 @@ inline bool ieee802154_prepare_for_ack(struct net_if *iface, struct net_pkt *pkt
  struct ieee802154_context *ctx = net_if_l2_data(iface);
 
  ctx->ack_seq = fs->sequence;
- ctx->ack_received = false;
- k_sem_init(&ctx->ack_lock, 0, K_SEM_MAX_LIMIT);
+ if (k_sem_count_get(&ctx->ack_lock) == 1U) {
+ k_sem_take(&ctx->ack_lock, K_NO_WAIT);
+ }
 
  return true;
  }
@@ -139,7 +140,6 @@ enum net_verdict ieee802154_handle_ack(struct net_if *iface, struct net_pkt *pkt
  return NET_CONTINUE;
  }
 
- ctx->ack_received = true;
  k_sem_give(&ctx->ack_lock);
 
  /* TODO: Release packet in L2 as we're taking ownership. */
@@ -152,23 +152,26 @@ enum net_verdict ieee802154_handle_ack(struct net_if *iface, struct net_pkt *pkt
 inline int ieee802154_wait_for_ack(struct net_if *iface, bool ack_required)
 {
  struct ieee802154_context *ctx = net_if_l2_data(iface);
+ int ret;
 
  if (!ack_required ||
  (ieee802154_radio_get_hw_capabilities(iface) & IEEE802154_HW_TX_RX_ACK)) {
  __ASSERT_NO_MSG(ctx->ack_seq == 0U);
  return 0;
  }
 
- if (k_sem_take(&ctx->ack_lock, K_MSEC(10)) == 0) {
- /* We reinit the semaphore in case ieee802154_handle_ack()
- * got called multiple times.
- */
- k_sem_init(&ctx->ack_lock, 0, K_SEM_MAX_LIMIT);
+ ret = k_sem_take(&ctx->ack_lock, K_MSEC(10));
+ if (ret == 0) {
+ /* no-op */
+ } else if (ret == -EAGAIN) {
+ ret = -ETIME;
+ } else {
+ NET_ERR("Error while waiting for ACK.");
+ ret = -EFAULT;
  }
 
  ctx->ack_seq = 0U;
-
- return ctx->ack_received ? 0 : -ETIME;
+ return ret;
 }
 
 int ieee802154_radio_send(struct net_if *iface, struct net_pkt *pkt, struct net_buf *frag)
@@ -619,6 +622,7 @@ void ieee802154_init(struct net_if *iface)
  NET_DBG("Initializing IEEE 802.15.4 stack on iface %p", iface);
 
  k_sem_init(&ctx->ctx_lock, 1, 1);
+ k_sem_init(&ctx->ack_lock, 0, 1);
 
  /* no need to lock the context here as it has
  * not been published yet.

diff --git a/subsys/net/l2/ieee802154/ieee802154_frame.c b/subsys/net/l2/ieee802154/ieee802154_frame.c
@@ -914,8 +914,8 @@ bool ieee802154_create_ack_frame(struct net_if *iface, struct net_pkt *pkt, uint
 
  fs = generate_fcf_grounds(&p_buf, false);
 
- fs->fc.dst_addr_mode = 0U;
- fs->fc.src_addr_mode = 0U;
+ fs->fc.dst_addr_mode = IEEE802154_ADDR_MODE_NONE;
+ fs->fc.src_addr_mode = IEEE802154_ADDR_MODE_NONE;
 
  fs->fc.frame_type = IEEE802154_FRAME_TYPE_ACK;
  fs->sequence = seq;