From 1edde90d91fff21343bdb8560eafcba6d5cf1331 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=C5=81ukasz=20Duda?= <lukasz.duda@nordicsemi.no>
Date: Mon, 10 Feb 2020 02:12:17 +0100
Subject: [PATCH] [sub-mac] fix incorrect timer configuration for energy
 scanning (#4538)

This fixes the implementation of Energy Scanning in case the platform
does not support it, but uses timer with microsecond resolution. This
is not the case with nRF528xx but found it during code inspection.

I've verified that after removing OT_RADIO_CAPS_ENERGY_SCAN
capability, the Energy Scan now works correctly.
---
 src/core/mac/sub_mac.cpp | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/core/mac/sub_mac.cpp b/src/core/mac/sub_mac.cpp
index c5c05ac1d..8ff1b0da6 100644
--- a/src/core/mac/sub_mac.cpp
+++ b/src/core/mac/sub_mac.cpp
@@ -431,6 +431,8 @@ exit:
 
 void SubMac::SampleRssi(void)
 {
+    assert(!RadioSupportsEnergyScan());
+
     int8_t rssi = GetRssi();
 
     if (rssi != kInvalidRssiValue)
@@ -443,7 +445,11 @@ void SubMac::SampleRssi(void)
 
     if (TimerMilli::GetNow() < mEnergyScanEndTime)
     {
+#if OPENTHREAD_CONFIG_PLATFORM_USEC_TIMER_ENABLE
+        mTimer.StartAt(mTimer.GetFireTime(), kEnergyScanRssiSampleInterval * 1000UL);
+#else
         mTimer.StartAt(mTimer.GetFireTime(), kEnergyScanRssiSampleInterval);
+#endif
     }
     else
     {