From fa1f1085bc063da5a44f779c9b655b7026c52d68 Mon Sep 17 00:00:00 2001
From: Arend van Spriel <arend.vanspriel@broadcom.com>
Date: Fri, 2 Aug 2019 13:31:00 +0200
Subject: [PATCH] cfg80211: util: add 6GHz channel to freq conversion and vice versa
Git-commit: fa1f1085bc063da5a44f779c9b655b7026c52d68
Patch-mainline: v5.4-rc1
References: jsc#SLE-13430

Extend the functions ieee80211_channel_to_frequency() and
ieee80211_frequency_to_channel() to support 6GHz band according
specification in 802.11ax D4.1 27.3.22.2.

Reviewed-by: Pieter-Paul Giesberts <pieter-paul.giesberts@broadcom.com>
Reviewed-by: Leon Zegers <leon.zegers@broadcom.com>
Signed-off-by: Arend van Spriel <arend.vanspriel@broadcom.com>
Link: https://lore.kernel.org/r/1564745465-21234-4-git-send-email-arend.vanspriel@broadcom.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 net/wireless/util.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/net/wireless/util.c b/net/wireless/util.c
index d0e35b7b9e35..c18d4fc440f4 100644
--- a/net/wireless/util.c
+++ b/net/wireless/util.c
@@ -91,6 +91,11 @@ int ieee80211_channel_to_frequency(int chan, enum nl80211_band band)
 		else
 			return 5000 + chan * 5;
 		break;
+	case NL80211_BAND_6GHZ:
+		/* see 802.11ax D4.1 27.3.22.2 */
+		if (chan <= 253)
+			return 5940 + chan * 5;
+		break;
 	case NL80211_BAND_60GHZ:
 		if (chan < 7)
 			return 56160 + chan * 2160;
@@ -111,8 +116,11 @@ int ieee80211_frequency_to_channel(int freq)
 		return (freq - 2407) / 5;
 	else if (freq >= 4910 && freq <= 4980)
 		return (freq - 4000) / 5;
-	else if (freq <= 45000) /* DMG band lower limit */
+	else if (freq < 5940)
 		return (freq - 5000) / 5;
+	else if (freq <= 45000) /* DMG band lower limit */
+		/* see 802.11ax D4.1 27.3.22.2 */
+		return (freq - 5940) / 5;
 	else if (freq >= 58320 && freq <= 70200)
 		return (freq - 56160) / 2160;
 	else
-- 
2.16.4