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Linux Mastering Development

8812au driver – power parameters

i’m trying to understand the behavior of my Alpha wlan card, generally it works fine, but my questions are related to more advanced subjects.

Runs on ubuntu 16.04

kernel version:
4.4.0-131-generic #157-Ubuntu SMP Thu Jul 12 15:51:36 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux

lshw -C network:
configuration: broadcast=yes driver=8812au multicast=yes wireless=IEEE 802.11abg

modinfo 8812au:

parm:           rtw_tx_pwr_lmt_enable:0:Disable, 1:Enable, 2: Depend on efuse (int)
parm:           rtw_tx_pwr_by_rate:0:Disable, 1:Enable, 2: Depend on efuse (int)

parm:           rtw_target_tx_pwr_2g_a:2.4G target tx power (unit:dBm) of RF path A for each rate section, should match the real calibrate power, -1: undefined (array of int)
parm:           rtw_target_tx_pwr_2g_b:2.4G target tx power (unit:dBm) of RF path B for each rate section, should match the real calibrate power, -1: undefined (array of int)
parm:           rtw_target_tx_pwr_2g_c:2.4G target tx power (unit:dBm) of RF path C for each rate section, should match the real calibrate power, -1: undefined (array of int)
parm:           rtw_target_tx_pwr_2g_d:2.4G target tx power (unit:dBm) of RF path D for each rate section, should match the real calibrate power, -1: undefined (array of int)
parm:           rtw_target_tx_pwr_5g_a:5G target tx power (unit:dBm) of RF path A for each rate section, should match the real calibrate power, -1: undefined (array of int)
parm:           rtw_target_tx_pwr_5g_b:5G target tx power (unit:dBm) of RF path B for each rate section, should match the real calibrate power, -1: undefined (array of int)
parm:           rtw_target_tx_pwr_5g_c:5G target tx power (unit:dBm) of RF path C for each rate section, should match the real calibrate power, -1: undefined (array of int)
parm:           rtw_target_tx_pwr_5g_d:5G target tx power (unit:dBm) of RF path D for each rate section, should match the real calibrate power, -1: undefined (array of int)

I’m coming from the wireless chipset validation world, and from my best knowledge I know that most of the wireless chipsets are calibrated at the production stage and those calibrated values are written to eeprom. Trying to understand the pasted lines from modinfo and what is the right configuration.
what is the chosen mode in the first two lines ? 0/1/2?

rtw_tx_pwr_lmt_enable
rtw_tx_pwr_by_rate

and what is the meaning of the rest of the 2g/5g lines ? is the driver is not using the calibrated values ?

The Alpha card works on two bands 2.4 & 5 ghz , one antenna per band, and probably x2 RF paths for each (Tx/Rx) so why ABCD paths per band ? is it real ?

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