ath5k: fix setup for CAB queue

The beacon sent gating doesn't seem to work with any combination
of flags.  Thus, buffered frames tend to stay buffered forever,
using up tx descriptors.

Instead, use the DBA gating and hold transmission of the buffered
frames until 80% of the beacon interval has elapsed using the ready
time.  This fixes the following error in AP mode:

   ath5k phy0: no further txbuf available, dropping packet

Add a comment to acknowledge that this isn't the best solution.

Signed-off-by: Bob Copeland <me@bobcopeland.com>
Acked-by: Nick Kossifidis <mickflemm@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 3 insertions, 2 deletions

diff --git a/drivers/net/wireless/ath/ath5k/qcu.c b/drivers/net/wireless/ath/ath5k/qcu.c
index abe36c0d139..9122a8556f4 100644
--- a/drivers/net/wireless/ath/ath5k/qcu.c
+++ b/drivers/net/wireless/ath/ath5k/qcu.c
@@ -408,12 +408,13 @@ int ath5k_hw_reset_tx_queue(struct ath5k_hw *ah, unsigned int queue)
                         break;
 
                 case AR5K_TX_QUEUE_CAB:
+                        /* XXX: use BCN_SENT_GT, if we can figure out how */
                         AR5K_REG_ENABLE_BITS(ah, AR5K_QUEUE_MISC(queue),
-                                AR5K_QCU_MISC_FRSHED_BCN_SENT_GT |
+                                AR5K_QCU_MISC_FRSHED_DBA_GT |
                                 AR5K_QCU_MISC_CBREXP_DIS |
                                 AR5K_QCU_MISC_CBREXP_BCN_DIS);
 
-                        ath5k_hw_reg_write(ah, ((AR5K_TUNE_BEACON_INTERVAL -
+                        ath5k_hw_reg_write(ah, ((tq->tqi_ready_time -
                                 (AR5K_TUNE_SW_BEACON_RESP -
                                 AR5K_TUNE_DMA_BEACON_RESP) -
                                 AR5K_TUNE_ADDITIONAL_SWBA_BACKOFF) * 1024) |