cfg80211: add debug print when processing a channel

In the worst case you are seeing really odd things you want
more information than what is provided right now, for those
that insist and want debug info through CONFIG_CFG80211_REG_DEBUG
provide a print of when we are processing a channel and with what
regulatory rule.

Cc: Easwar Krishnan <easwar.krishnan@atheros.com>
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: Senthil Balasubramanian <senthilkumar@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

net/wireless/reg.c

@@ -728,6 +728,41 @@ static const char *reg_initiator_name(enum nl80211_reg_initiator initiator)
 		return "Set by bug";
 	}
 }
+
+static void chan_reg_rule_print_dbg(struct ieee80211_channel *chan,
+				    u32 desired_bw_khz,
+				    const struct ieee80211_reg_rule *reg_rule)
+{
+	const struct ieee80211_power_rule *power_rule;
+	const struct ieee80211_freq_range *freq_range;
+	char max_antenna_gain[32];
+
+	power_rule = &reg_rule->power_rule;
+	freq_range = &reg_rule->freq_range;
+
+	if (!power_rule->max_antenna_gain)
+		snprintf(max_antenna_gain, 32, "N/A");
+	else
+		snprintf(max_antenna_gain, 32, "%d", power_rule->max_antenna_gain);
+
+	REG_DBG_PRINT("cfg80211: Updating information on frequency %d MHz "
+		      "for %d a MHz width channel with regulatory rule:\n",
+		      chan->center_freq,
+		      KHZ_TO_MHZ(desired_bw_khz));
+
+	REG_DBG_PRINT("cfg80211: %d KHz - %d KHz @  KHz), (%s mBi, %d mBm)\n",
+		      freq_range->start_freq_khz,
+		      freq_range->end_freq_khz,
+		      max_antenna_gain,
+		      power_rule->max_eirp);
+}
+#else
+static void chan_reg_rule_print_dbg(struct ieee80211_channel *chan,
+				    u32 desired_bw_khz,
+				    const struct ieee80211_reg_rule *reg_rule)
+{
+	return;
+}
 #endif
 
 /*
@@ -790,6 +825,8 @@ static void handle_channel(struct wiphy *wiphy,
 		return;
 	}
 
+	chan_reg_rule_print_dbg(chan, desired_bw_khz, reg_rule);
+
 	power_rule = &reg_rule->power_rule;
 	freq_range = &reg_rule->freq_range;
 
@@ -1134,6 +1171,8 @@ static void handle_channel_custom(struct wiphy *wiphy,
 		return;
 	}
 
+	chan_reg_rule_print_dbg(chan, desired_bw_khz, reg_rule);
+
 	power_rule = &reg_rule->power_rule;
 	freq_range = &reg_rule->freq_range;