ath9k: Fix bug in TX DMA termination

Removing the module was slow because ath9k_hw_stopdma()
was looping for a long time quantum. Use reasonable
values now to fix this issue.

Signed-off-by: Sujith <Sujith.Manoharan@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 25 insertions, 6 deletions

diff --git a/drivers/net/wireless/ath9k/mac.c b/drivers/net/wireless/ath9k/mac.c
index af32d091dc38..ef832a5ebbd8 100644
--- a/drivers/net/wireless/ath9k/mac.c
+++ b/drivers/net/wireless/ath9k/mac.c
@@ -107,14 +107,32 @@ bool ath9k_hw_updatetxtriglevel(struct ath_hal *ah, bool bIncTrigLevel)
 
 bool ath9k_hw_stoptxdma(struct ath_hal *ah, u32 q)
 {
+#define ATH9K_TX_STOP_DMA_TIMEOUT       4000    /* usec */
+#define ATH9K_TIME_QUANTUM              100     /* usec */
+
+        struct ath_hal_5416 *ahp = AH5416(ah);
+        struct ath9k_hw_capabilities *pCap = &ah->ah_caps;
+        struct ath9k_tx_queue_info *qi;
         u32 tsfLow, j, wait;
+        u32 wait_time = ATH9K_TX_STOP_DMA_TIMEOUT / ATH9K_TIME_QUANTUM;
+
+        if (q >= pCap->total_queues) {
+                DPRINTF(ah->ah_sc, ATH_DBG_QUEUE, "invalid queue num %u\n", q);
+                return false;
+        }
+
+        qi = &ahp->ah_txq[q];
+        if (qi->tqi_type == ATH9K_TX_QUEUE_INACTIVE) {
+                DPRINTF(ah->ah_sc, ATH_DBG_QUEUE, "inactive queue\n");
+                return false;
+        }
 
         REG_WRITE(ah, AR_Q_TXD, 1 << q);
 
-        for (wait = 1000; wait != 0; wait--) {
+        for (wait = wait_time; wait != 0; wait--) {
                 if (ath9k_hw_numtxpending(ah, q) == 0)
                         break;
-                udelay(100);
+                udelay(ATH9K_TIME_QUANTUM);
         }
 
         if (ath9k_hw_numtxpending(ah, q)) {
@@ -144,8 +162,7 @@ bool ath9k_hw_stoptxdma(struct ath_hal *ah, u32 q)
                 udelay(200);
                 REG_CLR_BIT(ah, AR_TIMER_MODE, AR_QUIET_TIMER_EN);
 
-                wait = 1000;
-
+                wait = wait_time;
                 while (ath9k_hw_numtxpending(ah, q)) {
                         if ((--wait) == 0) {
                                 DPRINTF(ah->ah_sc, ATH_DBG_XMIT,
@@ -153,15 +170,17 @@ bool ath9k_hw_stoptxdma(struct ath_hal *ah, u32 q)
                                         "msec after killing last frame\n");
                                 break;
                         }
-                        udelay(100);
+                        udelay(ATH9K_TIME_QUANTUM);
                 }
 
                 REG_CLR_BIT(ah, AR_DIAG_SW, AR_DIAG_FORCE_CH_IDLE_HIGH);
         }
 
         REG_WRITE(ah, AR_Q_TXD, 0);
-
         return wait != 0;
+
+#undef ATH9K_TX_STOP_DMA_TIMEOUT
+#undef ATH9K_TIME_QUANTUM
 }
 
 bool ath9k_hw_filltxdesc(struct ath_hal *ah, struct ath_desc *ds,