ath9k: Add debugfs file for RX errors

This file can be used to track frame reception errors.
PHY error counts are also added.

Location: ath9k/phy#/recv

Signed-off-by: Sujith <Sujith.Manoharan@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/ath/ath9k/debug.h b/drivers/net/wireless/ath/ath9k/debug.h
index 536663e..86780e6 100644
--- a/drivers/net/wireless/ath/ath9k/debug.h
+++ b/drivers/net/wireless/ath/ath9k/debug.h
@@ -116,10 +116,35 @@
 	u32 delim_underrun;
 };
 
+/**
+ * struct ath_rx_stats - RX Statistics
+ * @crc_err: No. of frames with incorrect CRC value
+ * @decrypt_crc_err: No. of frames whose CRC check failed after
+	decryption process completed
+ * @phy_err: No. of frames whose reception failed because the PHY
+	encountered an error
+ * @mic_err: No. of frames with incorrect TKIP MIC verification failure
+ * @pre_delim_crc_err: Pre-Frame delimiter CRC error detections
+ * @post_delim_crc_err: Post-Frame delimiter CRC error detections
+ * @decrypt_busy_err: Decryption interruptions counter
+ * @phy_err_stats: Individual PHY error statistics
+ */
+struct ath_rx_stats {
+	u32 crc_err;
+	u32 decrypt_crc_err;
+	u32 phy_err;
+	u32 mic_err;
+	u32 pre_delim_crc_err;
+	u32 post_delim_crc_err;
+	u32 decrypt_busy_err;
+	u32 phy_err_stats[ATH9K_PHYERR_MAX];
+};
+
 struct ath_stats {
 	struct ath_interrupt_stats istats;
 	struct ath_rc_stats rcstats[RATE_TABLE_SIZE];
 	struct ath_tx_stats txstats[ATH9K_NUM_TX_QUEUES];
+	struct ath_rx_stats rxstats;
 };
 
 struct ath9k_debug {
@@ -130,6 +155,7 @@
 	struct dentry *debugfs_rcstat;
 	struct dentry *debugfs_wiphy;
 	struct dentry *debugfs_xmit;
+	struct dentry *debugfs_recv;
 	struct ath_stats stats;
 };
 
@@ -142,6 +168,7 @@
 void ath_debug_stat_rc(struct ath_softc *sc, int final_rate);
 void ath_debug_stat_tx(struct ath_softc *sc, struct ath_txq *txq,
 		       struct ath_buf *bf);
+void ath_debug_stat_rx(struct ath_softc *sc, struct ath_buf *bf);
 void ath_debug_stat_retries(struct ath_softc *sc, int rix,
 			    int xretries, int retries, u8 per);
 
@@ -181,6 +208,11 @@
 {
 }
 
+static inline void ath_debug_stat_rx(struct ath_softc *sc,
+				     struct ath_buf *bf)
+{
+}
+
 static inline void ath_debug_stat_retries(struct ath_softc *sc, int rix,
 					  int xretries, int retries, u8 per)
 {