SX1261 radio and IN865 region, shall IN865_DEFAULT_MAX_EIRP be modified

[dagerlandsson]

When building a IN865 device and using SX1261 radio, shall IN865_DEFAULT_MAX_EIRP be changed to 15 + the antenna gain?

As I have understand it SX1261 can only output 15dBm and default antenna gain is 2.15 so the device will not be able to produce higher EIRP than 17.15dBm. When running now I can see that the mac and region layer tries to set power higher than radio layer can handle so it is clamped in SX126xSetTxParams.

Additional question is, in SX126xSetTxParams shall it be if(power >= 15) instead of (power==15)? In current code the result is that if higher layers of code want to have power > 15, chip will be configured for 14 (not 15 as expected)

Background:
We have problems to pass the TxPower test in LCTT. Device tries to use power 28 for high power, 28 is then limited down to 14 in radio layer.
In low power step it uses power 8 (30-antennagain-20). The difference in power between 14 and 8 is not enough to get 6db difference in RSSI so the test case fails.