It is not straightforward to the newcomer that a single skb can be sent at a time and that the internal process is to stop the queue when processing a frame before re-enabling it. Make this clear by documenting the ieee802154_wake/stop_queue() helpers. Signed-off-by: Miquel Raynal <miquel.raynal@xxxxxxxxxxx> --- include/net/mac802154.h | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/include/net/mac802154.h b/include/net/mac802154.h index d524ffb9eb25..94b2e3008e77 100644 --- a/include/net/mac802154.h +++ b/include/net/mac802154.h @@ -464,6 +464,12 @@ void ieee802154_rx_irqsafe(struct ieee802154_hw *hw, struct sk_buff *skb, * ieee802154_wake_queue - wake ieee802154 queue * @hw: pointer as obtained from ieee802154_alloc_hw(). * + * Tranceivers have either one transmit framebuffer or one framebuffer for both + * transmitting and receiving. Hence, the core only handles one frame at a time + * for each phy, which means we had to stop the queue to avoid new skb to come + * during the transmission. The queue then needs to be woken up after the + * operation. + * * Drivers should use this function instead of netif_wake_queue. */ void ieee802154_wake_queue(struct ieee802154_hw *hw); @@ -472,6 +478,12 @@ void ieee802154_wake_queue(struct ieee802154_hw *hw); * ieee802154_stop_queue - stop ieee802154 queue * @hw: pointer as obtained from ieee802154_alloc_hw(). * + * Tranceivers have either one transmit framebuffer or one framebuffer for both + * transmitting and receiving. Hence, the core only handles one frame at a time + * for each phy, which means we need to tell upper layers to stop giving us new + * skbs while we are busy with the transmitted one. The queue must then be + * stopped before transmitting. + * * Drivers should use this function instead of netif_stop_queue. */ void ieee802154_stop_queue(struct ieee802154_hw *hw); -- 2.27.0