ath5k: Disable interrupts in ath5k_hw_get_tsf64

The code in ath5k_hw_get_tsf64() is time critical and will return wrong results
if we get interrupted, so disable local interrupts.

Signed-off-by: Bruno Randolf <br1@einfach.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/drivers/net/wireless/ath/ath5k/pcu.c b/drivers/net/wireless/ath/ath5k/pcu.c
index 604114fb34b1..095d30b50ec7 100644
--- a/drivers/net/wireless/ath/ath5k/pcu.c
+++ b/drivers/net/wireless/ath/ath5k/pcu.c
@@ -495,6 +495,10 @@ u64 ath5k_hw_get_tsf64(struct ath5k_hw *ah)
 {
         u32 tsf_lower, tsf_upper1, tsf_upper2;
         int i;
+        unsigned long flags;
+
+        /* This code is time critical - we don't want to be interrupted here */
+        local_irq_save(flags);
 
         /*
          * While reading TSF upper and then lower part, the clock is still
@@ -517,6 +521,8 @@ u64 ath5k_hw_get_tsf64(struct ath5k_hw *ah)
                 tsf_upper1 = tsf_upper2;
         }
 
+        local_irq_restore(flags);
+
         WARN_ON( i == ATH5K_MAX_TSF_READ );
 
         return (((u64)tsf_upper1 << 32) | tsf_lower);