mwl8k: fix pci dma mapping leak in mwl8k_post_cmd() error path

Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/mwl8k.c

@@ -1439,8 +1439,11 @@ static int mwl8k_post_cmd(struct ieee80211_hw *hw, struct mwl8k_cmd_pkt *cmd)
 		return -ENOMEM;
 
 	rc = mwl8k_fw_lock(hw);
-	if (rc)
+	if (rc) {
+		pci_unmap_single(priv->pdev, dma_addr, dma_size,
+						PCI_DMA_BIDIRECTIONAL);
 		return rc;
+	}
 
 	priv->hostcmd_wait = &cmd_wait;
 	iowrite32(dma_addr, regs + MWL8K_HIU_GEN_PTR);