net: wifi: shell: only process scan events during requested scan

[EricNRS]

The scan events are always enabled which means if another software component requests a scan, then the WiFi shell scan printouts will also be sent to the shell. This change only enables the network management scan events when a user has requested a scan.

Without the change when my application does a scan to find the best channel:

uart> config wifi_channel
Scanning for best channels
SSID IoT, Channel 11, RSSI -46 dBm
SSID IoT, Channel 11, RSSI -63 dBm
SSID IoT, Channel 6, RSSI -77 dBm
SSID IoT, Channel 1, RSSI -81 dBm
Scan completed
Best Channel: 11, Max RSSI: -46 dBm

# These are printed from the WiFi Shell even though it wasn't requested:
Num  | SSID                             (len) | Chan (Band)   | RSSI | Security        | BSSID             | MFP     
1    | IoT                              3     | 11   (2.4GHz) | -46  | WPA2-PSK        | -------------------- | Disable 
2    | IoT                              3     | 11   (2.4GHz) | -63  | WPA2-PSK        | --------------------  | Disable 
3    | IoT                              3     | 6    (2.4GHz) | -77  | WPA2-PSK        | --------------------  | Disable 
4    | IoT                              3     | 1    (2.4GHz) | -81  | WPA2-PSK        | --------------------  | Disable 
Scan request done

[EricNRS]

The change is ready to merge, but marking as a draft since I have not discussed it with anyone yet.

[MaochenWang1]

In you case, how your software component triggers scan? Call the net_mgmt(NET_REQUEST_WIFI_SCAN, iface, &params, sizeof(params))?
The wifi shell print log contains more detailed information than your component log, why not just use the wifi shell log directly？

[EricNRS]

In you case, how your software component triggers scan? Call the net_mgmt(NET_REQUEST_WIFI_SCAN, iface, &params, sizeof(params))? The wifi shell print log contains more detailed information than your component log, why not just use the wifi shell log directly？

Correct, I use net_mgmt(NET_REQUEST_WIFI_SCAN, iface, &params, sizeof(params)) to trigger the scan every 30 seconds which is then sorted to determine the best channel and perform a reconnect operation. This is all done automatically in software, so the logging output is just a nuisance. In addition, logging is kept to a minimum due to OTA costs.

[krish2718]

In you case, how your software component triggers scan? Call the net_mgmt(NET_REQUEST_WIFI_SCAN, iface, &params, sizeof(params))? The wifi shell print log contains more detailed information than your component log, why not just use the wifi shell log directly？

Correct, I use net_mgmt(NET_REQUEST_WIFI_SCAN, iface, &params, sizeof(params)) to trigger the scan every 30 seconds which is then sorted to determine the best channel and perform a reconnect operation. This is all done automatically in software, so the logging output is just a nuisance. In addition, logging is kept to a minimum due to OTA costs.

The change itself it fine, but can't you just disable Wi-Fi shell CONFIG_NET_L2_WIFI_SHELL=n? Shell is only for development.

[EricNRS]

In you case, how your software component triggers scan? Call the net_mgmt(NET_REQUEST_WIFI_SCAN, iface, &params, sizeof(params))? The wifi shell print log contains more detailed information than your component log, why not just use the wifi shell log directly？

Correct, I use net_mgmt(NET_REQUEST_WIFI_SCAN, iface, &params, sizeof(params)) to trigger the scan every 30 seconds which is then sorted to determine the best channel and perform a reconnect operation. This is all done automatically in software, so the logging output is just a nuisance. In addition, logging is kept to a minimum due to OTA costs.

The change itself it fine, but can't you just disable Wi-Fi shell CONFIG_NET_L2_WIFI_SHELL=n? Shell is only for development.

Yes, I am in field trials at the moment, so just wanted to keep some of the shell commands such as wifi connect and wifi disconnect, but I can reimplement them and disable the WiFi shell entirely. If nobody else sees any value in this change, then I am happy to abandon it.

[krish2718]

In you case, how your software component triggers scan? Call the net_mgmt(NET_REQUEST_WIFI_SCAN, iface, &params, sizeof(params))? The wifi shell print log contains more detailed information than your component log, why not just use the wifi shell log directly？

Correct, I use net_mgmt(NET_REQUEST_WIFI_SCAN, iface, &params, sizeof(params)) to trigger the scan every 30 seconds which is then sorted to determine the best channel and perform a reconnect operation. This is all done automatically in software, so the logging output is just a nuisance. In addition, logging is kept to a minimum due to OTA costs.

The change itself it fine, but can't you just disable Wi-Fi shell CONFIG_NET_L2_WIFI_SHELL=n? Shell is only for development.

Yes, I am in field trials at the moment, so just wanted to keep some of the shell commands such as wifi connect and wifi disconnect, but I can reimplement them and disable the WiFi shell entirely. If nobody else sees any value in this change, then I am happy to abandon it.

The change itself LGTM, only impact to shell is that (re)adding callback for every scan, but IMHO that should be fine.