iwlwifi: add num_of_sos_stats to statistics counter

When uCode detects number of beacon missed consecutively above the
internal missed beacon threshold (set by uCode), it will reset and
re-tune the radio in order to get out of bad PHY state.

This "num_of_sos_states" counter monitors number of time uCode
encounters this bad condition and has to re-tune the radio.

Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: Zhu Yi <yi.zhu@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/iwlwifi/iwl-commands.h

@@ -3095,7 +3095,12 @@ struct statistics_general {
 	__le32 ttl_timestamp;
 	struct statistics_div div;
 	__le32 rx_enable_counter;
-	__le32 reserved1;
+	/*
+	 * num_of_sos_states:
+	 *  count the number of times we have to re-tune
+	 *  in order to get out of bad PHY status
+	 */
+	__le32 num_of_sos_states;
 	__le32 reserved2;
 	__le32 reserved3;
 } __attribute__ ((packed));

drivers/net/wireless/iwlwifi/iwl-debugfs.c

@@ -1728,7 +1728,7 @@ static ssize_t iwl_dbgfs_ucode_general_stats_read(struct file *file,
 	struct iwl_priv *priv = file->private_data;
 	int pos = 0;
 	char *buf;
-	int bufsz = sizeof(struct statistics_general) * 8 + 250;
+	int bufsz = sizeof(struct statistics_general) * 10 + 300;
 	ssize_t ret;
 	struct statistics_general *general, *accum_general;
 	struct statistics_general *delta_general, *max_general;
@@ -1828,6 +1828,12 @@ static ssize_t iwl_dbgfs_ucode_general_stats_read(struct file *file,
 			 accum_general->rx_enable_counter,
 			 delta_general->rx_enable_counter,
 			 max_general->rx_enable_counter);
+	pos += scnprintf(buf + pos, bufsz - pos, ucode_stats_format,
+			 "num_of_sos_states:",
+			 le32_to_cpu(general->num_of_sos_states),
+			 accum_general->num_of_sos_states,
+			 delta_general->num_of_sos_states,
+			 max_general->num_of_sos_states);
 	ret = simple_read_from_buffer(user_buf, count, ppos, buf, pos);
 	kfree(buf);
 	return ret;