ath5k: Check RXE when setting RXDP

 * Make sure we are not trying to set RXDP while RX is active,
 for now ignore the return value.

 Signed-off-by: Nick Kossifidis <mickflemm@gmail.com>

Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/ath/ath5k/ath5k.h b/drivers/net/wireless/ath/ath5k/ath5k.h
index 629a5ee..b36d3a5 100644
--- a/drivers/net/wireless/ath/ath5k/ath5k.h
+++ b/drivers/net/wireless/ath/ath5k/ath5k.h
@@ -1168,7 +1168,7 @@
 void ath5k_hw_start_rx_dma(struct ath5k_hw *ah);
 int ath5k_hw_stop_rx_dma(struct ath5k_hw *ah);
 u32 ath5k_hw_get_rxdp(struct ath5k_hw *ah);
-void ath5k_hw_set_rxdp(struct ath5k_hw *ah, u32 phys_addr);
+int ath5k_hw_set_rxdp(struct ath5k_hw *ah, u32 phys_addr);
 int ath5k_hw_start_tx_dma(struct ath5k_hw *ah, unsigned int queue);
 int ath5k_hw_stop_tx_dma(struct ath5k_hw *ah, unsigned int queue);
 u32 ath5k_hw_get_txdp(struct ath5k_hw *ah, unsigned int queue);
diff --git a/drivers/net/wireless/ath/ath5k/dma.c b/drivers/net/wireless/ath/ath5k/dma.c
index bfdfcff..3fe634f 100644
--- a/drivers/net/wireless/ath/ath5k/dma.c
+++ b/drivers/net/wireless/ath/ath5k/dma.c
@@ -95,11 +95,18 @@
  * @ah: The &struct ath5k_hw
  * @phys_addr: RX descriptor address
  *
- * XXX: Should we check if rx is enabled before setting rxdp ?
+ * Returns -EIO if rx is active
  */
-void ath5k_hw_set_rxdp(struct ath5k_hw *ah, u32 phys_addr)
+int ath5k_hw_set_rxdp(struct ath5k_hw *ah, u32 phys_addr)
 {
+	if (ath5k_hw_reg_read(ah, AR5K_CR) & AR5K_CR_RXE) {
+		ATH5K_DBG(ah->ah_sc, ATH5K_DEBUG_DMA,
+				"tried to set RXDP while rx was active !\n");
+		return -EIO;
+	}
+
 	ath5k_hw_reg_write(ah, phys_addr, AR5K_RXDP);
+	return 0;
 }