summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
-rw-r--r--drivers/staging/et131x/et1310_rx.c20
1 files changed, 14 insertions, 6 deletions
diff --git a/drivers/staging/et131x/et1310_rx.c b/drivers/staging/et131x/et1310_rx.c
index 8f2e91fa0a86..10e21db57ac3 100644
--- a/drivers/staging/et131x/et1310_rx.c
+++ b/drivers/staging/et131x/et1310_rx.c
@@ -1177,12 +1177,20 @@ void et131x_handle_recv_interrupt(struct et131x_adapter *etdev)
static inline u32 bump_fbr(u32 *fbr, u32 limit)
{
- u32 v = *fbr;
- add_10bit(&v, 1);
- if (v > limit)
- v = (*fbr & ~ET_DMA10_MASK) ^ ET_DMA10_WRAP;
- *fbr = v;
- return v;
+ u32 v = *fbr;
+ v++;
+ /* This works for all cases where limit < 1024. The 1023 case
+ works because 1023++ is 1024 which means the if condition is not
+ taken but the carry of the bit into the wrap bit toggles the wrap
+ value correctly */
+ if ((v & ET_DMA10_MASK) > limit) {
+ v &= ~ET_DMA10_MASK;
+ v ^= ET_DMA10_WRAP;
+ }
+ /* For the 1023 case */
+ v &= (ET_DMA10_MASK|ET_DMA10_WRAP);
+ *fbr = v;
+ return v;
}
/**