Measure Channel State Information (CSI) using iwlwifi

Hi, I trying to measure CSI on NIC AX200/AX210 using iwlwifi driver. I found that it is implemented:

https://patchwork.kernel.org/project...uca@coelho.fi/

https://git.kernel.org/pub/scm/linux...1cef60821acb77

First I enable monitor mode:
Code:sudo iw phy phy0 interface add mon0 type monitor
sudo iw dev wlp4s0 del
sudo ifconfig mon0 up
sudo iw dev mon0 set freq 2437Then enable CSI:
Code:echo 1 > /sys/kernel/debug/iwlwifi/0000\:04\:00.0/iwlmvm/csi_enabledBut only once is CSI measured even when I repeat enable CSI command.

I try to add prints to iwlwifi and recompile for debug purpose which method is called:

[ 109.195678] CSI: iwl_mvm_send_csi_cmd
[ 109.415723] CSI: iwl_mvm_rx_csi_chunk
[ 109.415733] CSI: iwl_mvm_rx_csi_chunk
[ 115.763639] CSI: iwl_mvm_send_csi_cmd
[ 119.739798] CSI: iwl_mvm_send_csi_cmd

Here we can saw that I can repeat enable CSI but CSI was measured only once.

After firmware restart / iwlwifi module reload it work again only once at first time run command CSI enable.

Expecting continous measurement of CSI, not only once. Did I something wrong? Should I reset some NIC registers using driver or clear some variables?