From c6d93d1a28518e06eeef7cd33ca69975a132cce3 Mon Sep 17 00:00:00 2001
From: geeksville <kevinh@geeksville.com>
Date: Tue, 15 Sep 2020 18:54:50 -0700
Subject: [PATCH] fix #346 limit tx power in japan

---
 src/mesh/RF95Interface.cpp   |  2 ++
 src/mesh/RadioInterface.cpp  | 19 +++++++++++++++++++
 src/mesh/RadioInterface.h    |  6 ++++++
 src/mesh/SX1262Interface.cpp |  3 +++
 4 files changed, 30 insertions(+)

diff --git a/src/mesh/RF95Interface.cpp b/src/mesh/RF95Interface.cpp
index 3d03e403bc..594cec91f3 100644
--- a/src/mesh/RF95Interface.cpp
+++ b/src/mesh/RF95Interface.cpp
@@ -41,6 +41,8 @@ bool RF95Interface::init()
     if (power > MAX_POWER) // This chip has lower power limits than some
         power = MAX_POWER;
 
+    limitPower();
+    
     iface = lora = new RadioLibRF95(&module);
 
 #ifdef RF95_TCXO
diff --git a/src/mesh/RadioInterface.cpp b/src/mesh/RadioInterface.cpp
index 0cdd4da683..4d43d22ff1 100644
--- a/src/mesh/RadioInterface.cpp
+++ b/src/mesh/RadioInterface.cpp
@@ -136,6 +136,25 @@ void RadioInterface::applyModemConfig()
               power);
 }
 
+/**
+ * Some regulatory regions limit xmit power.
+ * This function should be called by subclasses after setting their desired power.  It might lower it
+ */
+void RadioInterface::limitPower()
+{
+    uint8_t maxPower = 255; // No limit
+
+#ifdef HW_VERSION_JP
+    maxPower = 13; // See https://github.com/meshtastic/Meshtastic-device/issues/346
+#endif
+    if (power > maxPower) {
+        DEBUG_MSG("Lowering transmit power because of regulatory limits\n");
+        power = maxPower;
+    }
+
+    DEBUG_MSG("Set radio: final power level=%d\n", power);
+}
+
 ErrorCode SimRadio::send(MeshPacket *p)
 {
     DEBUG_MSG("SimRadio.send\n");
diff --git a/src/mesh/RadioInterface.h b/src/mesh/RadioInterface.h
index b8cba208d2..645ee5c057 100644
--- a/src/mesh/RadioInterface.h
+++ b/src/mesh/RadioInterface.h
@@ -119,6 +119,12 @@ class RadioInterface : protected concurrency::NotifiedWorkerThread
 
     virtual void loop() {} // Idle processing
 
+    /**
+     * Some regulatory regions limit xmit power.
+     * This function should be called by subclasses after setting their desired power.  It might lower it
+     */
+    void limitPower();
+
     /**
      * Convert our modemConfig enum into wf, sf, etc...
      *
diff --git a/src/mesh/SX1262Interface.cpp b/src/mesh/SX1262Interface.cpp
index 75a84034dc..130f340c3b 100644
--- a/src/mesh/SX1262Interface.cpp
+++ b/src/mesh/SX1262Interface.cpp
@@ -43,6 +43,9 @@ bool SX1262Interface::init()
 
     if (power > 22) // This chip has lower power limits than some
         power = 22;
+
+    limitPower();
+
     int res = lora.begin(freq, bw, sf, cr, syncWord, power, currentLimit, preambleLength, tcxoVoltage, useRegulatorLDO);
     DEBUG_MSG("SX1262 init result %d\n", res);