From 5ae63817b957949d6521eb0f3e795d93b28abf59 Mon Sep 17 00:00:00 2001
From: Denis Kenzior <denkenz@gmail.com>
Date: Wed, 10 Jun 2015 15:31:13 -0500
Subject: [PATCH] scan: Add scan_freq_to_channel

---
 src/scan.c | 49 +++++++++++++++++++++++++++++++++++++++++++++++++
 src/scan.h |  7 +++++++
 2 files changed, 56 insertions(+)

diff --git a/src/scan.c b/src/scan.c
index 873f4bf2..263ba699 100644
--- a/src/scan.c
+++ b/src/scan.c
@@ -615,6 +615,55 @@ static void scan_notify(struct l_genl_msg *msg, void *user_data)
 	}
 }
 
+uint8_t scan_freq_to_channel(uint32_t freq, enum scan_band *out_band)
+{
+	uint32_t channel = 0;
+
+	if (freq >= 2412 && freq <= 2484) {
+		if (freq == 2484)
+			channel = 14;
+		else {
+			channel = freq - 2407;
+
+			if (channel % 5)
+				return 0;
+
+			channel /= 5;
+		}
+
+		if (out_band)
+			*out_band = SCAN_BAND_2_4_GHZ;
+
+		return channel;
+	}
+
+	if (freq >= 5005 && freq < 5900) {
+		if (channel % 5)
+			return 0;
+
+		channel = (freq - 5000) / 5;
+
+		if (out_band)
+			*out_band = SCAN_BAND_5_GHZ;
+
+		return channel;
+	}
+
+	if (freq >= 4905 && freq < 5000) {
+		if (channel % 5)
+			return 0;
+
+		channel = (freq - 4000) / 5;
+
+		if (out_band)
+			*out_band = SCAN_BAND_5_GHZ;
+
+		return channel;
+	}
+
+	return 0;
+}
+
 bool scan_init(struct l_genl_family *in, scan_notify_func_t func)
 {
 	nl80211 = in;
diff --git a/src/scan.h b/src/scan.h
index d237b822..76bddd2e 100644
--- a/src/scan.h
+++ b/src/scan.h
@@ -27,6 +27,11 @@ enum scan_ssid_security {
 	SCAN_SSID_SECURITY_8021X,
 };
 
+enum scan_band {
+	SCAN_BAND_2_4_GHZ,
+	SCAN_BAND_5_GHZ,
+};
+
 typedef void (*scan_func_t)(struct l_genl_msg *msg, void *user_data);
 typedef bool (*scan_notify_func_t)(uint32_t wiphy, uint32_t ifindex,
 					struct l_queue *bss_list);
@@ -63,5 +68,7 @@ void bss_get_supported_ciphers(struct scan_bss *bss,
 				uint16_t *pairwise_ciphers,
 				uint16_t *group_ciphers);
 
+uint8_t scan_freq_to_channel(uint32_t freq, enum scan_band *out_band);
+
 bool scan_init(struct l_genl_family *in, scan_notify_func_t func);
 bool scan_free();