Why calling btmgmt conn-info on a connected device returns with: status 0x02 (Not Connected)

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Im trying to read the RSSI values of a connected BLE device using btmgmt rust library, and always getting 127.

    pub fn get_rssi(&self) -> Result<i8, Box<std::error::Error>> {
        let btmgmt = btmgmt::BTMgmt::new()?;
        let address = btmgmt::address::Address::from_string(
            self.addr.as_str(),
            btmgmt::address::AddressType::LeRandom,
        )
        .ok_or("invalid address")?;

        let ci = btmgmt.get_connection_info(u16::from(self.adapter_id), &address)?;

        Ok(ci.rssi)
    }

I know for sure that the device is connected, and had services resolved, here’s bluetoothctl output:

Device DA:A4:58:46:AE:9F (random)
    Name: Device_name
    Alias: Device_name
    Paired: no
    Trusted: yes
    Blocked: no
    Connected: yes #<------------------------------- Connecter yey 🙂
    LegacyPairing: no
    UUID: Vendor specific           (********-****-****-****-************)
    UUID: Generic Access Profile    (00001800-0000-1000-8000-00805f9b34fb)
    UUID: Generic Attribute Profile (00001801-0000-1000-8000-00805f9b34fb)
    RSSI: -33 #<------------------------------------ We even have RSSI here.
    AdvertisingFlags:

I’ve tryied to call btmgmt using cli, yet it complains that the devices is not connected:

$ sudo btmgmt conn-info DA:A4:58:46:AE:9F                                  
Get Conn Info for DA:A4:58:46:AE:9F (BR/EDR) failed. status 0x02 (Not Connected)

Just for sanity check, I’ve compared to my connected Bose QC3’s (Also BLE device) output:

$ sudo btmgmt conn-info 4C:87:5D:0C:B5:FC                                 
Connection Information for 4C:87:5D:0C:B5:FC (BR/EDR)
    RSSI 0  TX power -3 maximum TX power 12
  1. What am I missing?
  2. Why btmgmt cant get connection info, while it seems everything is resolved as expected by the output of bluetoothctl?

Bluez – 5.53
Kernel – 5.15.0-83-generic

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