Comment 5 for bug 1885663

iw dev info *reports* the same default txpower (20.00 dBm) for all kernels. It is only the actual received signal (at the access point) that varies. I paste the output of `iw dev wlo1 info` below for 5.4 and 5.8; 5.3 is the almost the same except it lacks the multicast TXQ lines:

Interface wlo1
 ifindex 2
 wdev 0x1
 addr 74:40:bb:2e:b8:c1
 ssid nullfarm
 type managed
 wiphy 0
 channel 6 (2437 MHz), width: 40 MHz, center1: 2447 MHz
 txpower 20.00 dBm
 multicast TXQ:
  qsz-byt qsz-pkt flows drops marks overlmt hashcol tx-bytes tx-packets
  0 0 0 0 0 0 0 0 0

On 5.8, `set txpower auto` sets it to be 30.00 dBm (as reported by rerunning `iw dev wlo1 info`). However, this does not noticeably change the received signal strength (as there is variation in received signal, a small difference in the mean would be hard to detect). I also tried `set txpower 100` to 1.00 dBm; this also does not appear to change the received signal strength. So I suspect the txpower setting must not be getting through to the hardware.

On 5.4, `set txpower auto` sets it to be 20.00 dBm (i.e., no change). Attempting to match 5.8 auto by `set txpower 3000` actually sets it to be 20.00. `set txpower 100` works but none of these changes to txpower affect the received signal strength.

On 5.3, `set txpower auto` sets it to be 30.00 dBm (same as 5.8). `set txpower 100` also works but again, none of these changes affect the received signal strength.

I am conducting these tests ~5m away from the access point, although through walls/floor. The 5.3 and 5.8 received signal strength is generally between -61 and -65 dBm while on 5.4 it is generally between -78 and -80 dBm.

A cold boot into 5.4 does not change the behavior.