[PATCH 1/3] dt-bindings: net: wireless: mt76: add power-limits node

[Felix Fietkau <nbd@xxxxxxxx>]

This subnode can be used to set per-rate tx power limits either per
country code / regdomain or globally.
These limits are typically provided by the device manufacturers and are
used to limit sideband emissions and stay within regulatory limits

Signed-off-by: Felix Fietkau <nbd@xxxxxxxx>
---
 .../bindings/net/wireless/mediatek,mt76.txt   | 47 +++++++++++++++++++
 1 file changed, 47 insertions(+)

diff --git a/Documentation/devicetree/bindings/net/wireless/mediatek,mt76.txt b/Documentation/devicetree/bindings/net/wireless/mediatek,mt76.txt
index ab7e7a00e534..9d9ace0cfbf9 100644
--- a/Documentation/devicetree/bindings/net/wireless/mediatek,mt76.txt
+++ b/Documentation/devicetree/bindings/net/wireless/mediatek,mt76.txt
@@ -36,6 +36,7 @@ Optional nodes:
 - led: Properties for a connected LED
   Optional properties:
     - led-sources: See Documentation/devicetree/bindings/leds/common.txt
+- power-limits: contains per-regdomain/channel rate power limit subnodes
 
 &pcie {
 	pcie0 {
@@ -76,3 +77,49 @@ wmac: wmac@18000000 {
 
 	power-domains = <&scpsys MT7622_POWER_DOMAIN_WB>;
 };
+
+
+Subnodes of power-limits:
+
+Properties:
+- country: One or more country codes, as used by the cfg80211 regdomain code
+- regdomain: "FCC", "ETSI" or "JP"
+
+If neither country, nor regdomain is specified, the power limits node is used
+as a fallback when no other subnode matches.
+
+Subnodes txpower-2g, txpower-5g:
+
+Properties:
+- channels: pairs of first and last channel number
+- cck: 4 half-dBm per-rate power limit values
+- ofdm: 8 half-dBm per-rate power limit values
+- mcs:
+	sets of per-rate power limit values for 802.11n/802.11ac rates for
+	multiple channel bandwidth settings.
+	Each set starts with the number of channel bandwidth settings for
+	which the rate set applies, followed by either 8 (MT7603/MT7628) or
+	10 (all other chips) power limit values.
+	The order of the channel bandwidth settings is: 20, 40, 80, 160 MHz.
+
+
+power-limit example:
+
+power-limits {
+	r0 {
+		regdomain = "FCC";
+		txpower-5g {
+			r1 {
+				channels = <36 48>;
+				ofdm = <23 23 23 23 23 23 23 23>;
+				mcs = <1 23 23 23 23 23 23 23 23 23 23>,
+					  <3 22 22 22 22 22 22 22 22 22 22>;
+			};
+			r2 {
+				channels = <100 181>;
+				ofdm = <14 14 14 14 14 14 14 14>;
+				mcs = <4 14 14 14 14 14 14 14 14 14 14>;
+			};
+		};
+	};
+};
-- 
2.24.0