[PATCH testing] mrf24j40: Move INIT_COMPLETION to before the packet is sent

From: Alan Ott
Date: Sun May 19 2013 - 20:05:52 EST

This avoids a race condition where the tx_complete interrupt could happen
before the completion is initialized.


David H,

Try this out and see if it changes anything for you. I put a bunch of
schedule_timeout()s in mrf24j40_tx() to basically guarantee that a reception
will happen during mrf24j40_tx(), and it seems to work. It would not work
before with said schedule_timeout() calls.


drivers/net/ieee802154/mrf24j40.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ieee802154/mrf24j40.c b/drivers/net/ieee802154/mrf24j40.c
index 556151d..0ea2a5a 100644
--- a/drivers/net/ieee802154/mrf24j40.c
+++ b/drivers/net/ieee802154/mrf24j40.c
@@ -345,6 +345,8 @@ static int mrf24j40_tx(struct ieee802154_dev *dev, struct sk_buff *skb)
if (ret)
goto err;

+ INIT_COMPLETION(devrec->tx_complete);
/* Set TXNTRIG bit of TXNCON to send packet */
ret = read_short_reg(devrec, REG_TXNCON, &val);
if (ret)
@@ -355,8 +357,6 @@ static int mrf24j40_tx(struct ieee802154_dev *dev, struct sk_buff *skb)
val |= 0x4;
write_short_reg(devrec, REG_TXNCON, val);

- INIT_COMPLETION(devrec->tx_complete);
/* Wait for the device to send the TX complete interrupt. */
ret = wait_for_completion_interruptible_timeout(

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