Sterling-LWB5+ WiFi 5 + Bluetooth 5.2 Module / USB Adapter

There are certain patch ranges within kernels 4.4 and 4.9 that need a modification so backports can build, the reason why we cannot fix it in backports is that we cannot track and differentiate between patch versions of the same 'major.minor' version of kernel. To fix this issue, move the function kobject_has_children from linux/kobject.h to drivers/base/core.c in your kernel source, rebuild the kernel and then rebuild backports.

Using the test scripts provided with BlueZ to setup a GATT server:

cd /lib/bluez/test/
./example-gatt-server &

Power on Bluetooth, start advertising and set to pairable:

# bluetoothctl
Agent registered
[bluetooth]# power on
Changing power on succeeded
[bluetooth]# advertise on
[bluetooth]# pairable on

Connect with Nordic's nRF smartphone app and read the fake battery level.

Unfortunately the LWB Series can only be configured for a static region. We do have options with our other radios, please contact support and we can make a recommendation based on your project's needs.

The LWB5+ is an embedded SDIO module and using an external slot may introduce some challenges. The external slot likely starts at 3.3 VIO and steps down to 1.8 VIO. If this is not the case, the following also addresses fixed VIO for both 1v8 and 3v3. As noted below, the M.2 variant only supports 1.8 VIO.

1. Run the LWB5+ at 3.3 VIO SD High Speed mode (module only, not M.2)
   1. Configure the LWB5+ DVK for 3.3 VIO via strapping switches (1,0) and VDDIO switched to 3v3
   2. Add no-1-8-v to the SDIO device node in the device tree
   3. Confirm the voltage step-down is disabled on the host
2. Run the LWB5+ at SDR speed by syncing VIO via jumper wire (module only, not M.2)
   1. If the host board exposes VIO of the external slot, depopulate the VDDIO switch on the LWB5+ DVK and wire the center pin directly to VIO on the host.
      1. An example is TP709 on the i.MX6UL EVK from NXP
   2. The external slot may not be fully capable of SDR104 @200MHz and the bus speed may have to be limited
      1. Example 100MHz device tree property: max-frequency = <100000000>;
3. Force the host to run at 1.8 VIO all the time (module and M.2)
   1. This requires modification to the host and is up to you to weigh the risk and devise a resolution
   2. The LWB5+ M.2 DVK will not need modification
   3. Configure the LWB5+ module DVK for 1.8 VIO via strapping switches (1,1) and VDDIO switched to 1v8
   4. The slot may not be capable of full 200MHz SDR104 operation, see note above about limiting bus speed

In order to be able to leverage the Modular Approval of a wireless module the following requirements have to be met:

• The RF circuitry must be shielded
• The module must have buffered modulation/data inputs. Module must inherently ensure compliance under host fault (watch dog) conditions
• The module must have a regulated power supply
• An antenna needs to be attached permanently or a unique antenna connector must be mounted on the module
• The module must be compliant with the regulations in a stand-alone configuration
• The module must be labeled with its permanently affixed FCC ID label or use an electronic display
• A user manual needs to provide comprehensive instructions to explain compliance requirements.
• The module must comply with RF exposure requirements

Simply log into GitHub, go to the corresponding release packages page and click the "Watch" button (eye icon) in the top right of the page. Some radios (such as the LWB Series) requires you to download firmware separately from the product page; this firmware is updated on the product page in conjunction with GitHub releases.

Release Packages

For the Sterling-LWB5+ Wifi module, Laird does not use the regular CYW4373 chip from Cypress but a version that supports extended temperature range by the name of CYP4373E.

It is best practice to include the source in your build system. If using Yocto, our external layer will do this for you.
Here is an example manually compiling using our SOM60 as a target in a Buildroot environment:

1. Download and extract the Sterling supplicant source.
2. Navigate to the "laird" directory.
3. Edit the config_laird file:
4. Find the following line, uncomment and change the path to your "openssl/include" directory:
   original line:
   #CFLAGS += -I/usr/local/openssl/include
   modified line:
   CFLAGS += -I/wb/buildroot/output/som60sd/build/host-libopenssl-1.1.1d/include
5. Run make with the following flags
   set:
CC="" for your cross-compile binary
PKG_CONFIG="" for your pkg-config binary
PKG_CONFIG_PATH="" for your pkgconfig directory
OBJCOPY="" for your objcopy binary

Note the following example is a single line command:
make CC="/wb/buildroot/output/som60sd/host/bin/arm-buildroot-linux-gnueabihf-gcc" PKG_CONFIG="/wb/buildroot/output/som60sd/host/bin/pkg-config" OBJCOPY="/wb/buildroot/output/som60sd/host/arm-buildroot-linux-gnueabihf/bin/objcopy" PKG_CONFIG_PATH="/wb/buildroot/output/som60sd/host/arm-buildroot-linux-gnueabihf/sysroot/usr/lib/pkgconfig"

In order to enable LPM mode on the Sterling-LWB, Sterling-LWB5 and Sterling-LWB5+ modules the options --enable_lpm and --enable_hci need to be added to the patchram command line expression:

# patchram -d --patchram /lib/firmware/brcm/4343w.hcd --enable_lpm --enable_hci --no2bytes  --tosleep 1000 /dev/ttyS1 c1 &

This also enables BT_HOST_WAKE (output) and BT_DEV_WAKE (input).
BT_DEV_WAKE needs to be asserted for the module to respond.

To activate BT, list controller information and scan for BT/BLE devices:

# bluetoothctl
Agent registered
[bluetooth]# power on
Changing power on succeeded
[bluetooth]# list
Controller C0:EE:40:50:00:00 summit [default]
[bluetooth]# scan on

To connect to a device acting as a peripheral:

[bluetooth]# scan on
Discovery started
[CHG] Controller C0:EE:40:50:00:00 Discovering: yes
[NEW] Device 4C:90:DE:92:00:00 Pixel XL
[CHG] Device 4C:90:DE:92:00:00 RSSI: -68
[CHG] Device 4C:90:DE:92:00:00 RSSI: -58
...
[NEW] Device 4C:90:DE:92:00:00 Pixel XL
[bluetooth]# scan off
Discovery stopped
[CHG] Controller C0:EE:40:50:00:00 Discovering: no
[CHG] Device 4C:90:DE:92:00:00 TxPower is nil
[CHG] Device 4C:90:DE:92:00:00 RSSI is nil
[bluetooth]# pair 4C:90:DE:92:00:00
Attempting to pair with 4C:90:DE:92:00:00
[CHG] Device 4C:90:DE:92:00:00 Connected: yes
[NEW] Primary Service
        /org/bluez/hci0/dev_4C_90_DE_92_00_00/service0001
        00001801-0000-1000-8000-00805f9b34fb
        Generic Attribute Profile
[NEW] Characteristic
        /org/bluez/hci0/dev_4C_90_DE_92_00_00/service0001/char0002
        00002a05-0000-1000-8000-00805f9b34fb
...
[NEW] Characteristic
        /org/bluez/hci0/dev_4C_90_DE_92_00_00/service003a/char003b
        00002a8a-0000-1000-8000-00805f9b34fb
        First Name
[NEW] Characteristic
        /org/bluez/hci0/dev_4C_90_DE_92_00_00/service003a/char003d
        00002a90-0000-1000-8000-00805f9b34fb
        Last Name
[NEW] Characteristic
        /org/bluez/hci0/dev_4C_90_DE_92_00_00/service003a/char003f
        00002a8c-0000-1000-8000-00805f9b34fb
        Gender
...
[CHG] Device 4C:90:DE:92:00:00 UUIDs: 0000181c-0000-1000-8000-00805f9b34fb
[CHG] Device 4C:90:DE:92:00:00 UUIDs: 0000aaa0-0000-1000-8000-aabbccddeeff
[CHG] Device 4C:90:DE:92:00:00 ServicesResolved: yes
Request confirmation
[agent] Confirm passkey 210165 (yes/no): yes
[Pixel XL]# trust 4C:90:DE:92:00:00
[CHG] Device 4C:90:DE:92:00:00 Trusted: yes
Changing 4C:90:DE:92:00:00 trust succeeded

The peripheral device is a Google Pixel XL running Android 10 using Nordic’s nRF app with an advertising profile setup with dummy information. If you pair with a device that does not have some kind of service running, it will disconnect, as BT/BLE has nothing to do.

We provide driver support via our fork of the backports package and integrate releases from Cypress/Infineon. Backports replaces the kernel-side Bluetooth stack and Wi-Fi stack including cfg80211 and driver. We regularly perform a kernel rebase to keep up with LTS releases which provides the benefit of running a modern stack on a range of kernels. We perform build verification regression testing including popular silicon vendor kernels such as Xilinx, nVidia, ST Micro, TI and NXP. All releases are QA validated in our automated testing system.

We support our customers integrating backports in different Linux build environments including Yocto, Buildroot and PetaLinux. Please contact support if integration assistance is needed.

CVEs that have been addressed are referenced in our release notes. If there is a new CVE or one that is not listed in our release notes, please submit a ticket using our support portal and we will provide the status.

Radio-specific release notes can be found in the corresponding GitHub repo: https://github.com/LairdCP/Release-Packages

If the binary returns "not found" or does not work after confirming the executable bit is set with chmod +x <filename>, then you will need to create a symlink pointing to the system's interpreter. The file tool will show the expected interpreter and architecture of a binary, readelf is a lot more verbose and is used to discover the expected "sonames" of shared libraries. These utilities do not have to be used on the target system and is convenient to use on a common x86 Linux machine. These utilities can be installed on Ubuntu with sudo apt install binutils.

Example output from the file command:
sterling_supplicant-arm-7.0.0.139/usr/sbin$ file wpa_supplicant
wpa_supplicant: ELF 32-bit LSB executable, ARM, EABI5 version 1 (SYSV), dynamically linked, interpreter /lib/ld-linux.so.3, for GNU/Linux 3.0.0, stripped

Example output from the readelf command:
sterling_supplicant-arm-7.0.0.139/usr/sbin$ readelf -ld wpa_supplicant Elf file type is EXEC (Executable file)
Entry point 0xba28
There are 10 program headers, starting at offset 52 Program Headers:
...
<edited>
...
      [Requesting program interpreter: /lib/ld-linux.so.3]
...
<edited>
...
Dynamic section at offset 0x176ee8 contains 30 entries:
  Tag        Type                         Name/Value
 0x00000001 (NEEDED)                     Shared library: [librt.so.1]
 0x00000001 (NEEDED)                     Shared library: [libnl-3.so.200]
 0x00000001 (NEEDED)                     Shared library: [libnl-genl-3.so.200]
 0x00000001 (NEEDED)                     Shared library: [libdl.so.2]
 0x00000001 (NEEDED)                     Shared library: [libdbus-1.so.3]
 0x00000001 (NEEDED)                     Shared library: [libgcc_s.so.1]
 0x00000001 (NEEDED)                     Shared library: [libc.so.6]
...
<edited>
...

To use this binary, we will have to confirm this symlink exists or create a new symlink pointing to the interpreter on the target filesystem:
cd /lib/
ls -l ld-*
-rwxr-xr-x    1 root     root        158772 Dec  2  2019 /lib/ld-2.26.so
ln -sf ld-2.26.so ld-linux.so.3
ls -l ld-*
-rwxr-xr-x    1 root     root        158772 Dec  2  2019 /lib/ld-2.26.so
lrwxrwxrwx    1 root     root            10 Dec 21 18:55 /lib/ld-linux.so.3 -> ld-2.26.so

If the binary now reports that a library is not found when executed, repeat the steps shown above for creating a library symlink/soname pointing to it's real name. This may require you to use the find command to discover the location of the library. Example for libnl-genl-3:
find / -name 'libnl-genl-3*' -exec ls -l {} 2>/dev/null \;
-rwxr-xr-x    1 root     root         18524 Feb 14 23:42 /usr/lib/libnl-genl-3.so.200.26.0
cd /usr/lib/
ln -sf libnl-genl-3.so.200.26.0 libnl-genl-3.so.200
ls -l libnl-genl-3*
-rwxr-xr-x    1 root     root         18524 Feb 14 23:42 /usr/lib/libnl-genl-3.so.200.26.0
lrwxrwxrwx    1 root     root            24 Feb 14 23:37 /usr/lib/libnl-genl-3.so.200 -> libnl-genl-3.so.200.26.0

If the library does not exist, you will have to include that package in your build. For instance if the above example libnl was missing, include the libnl package when building your filesystem.

The Sterling supplicant is based on the open-source wpa_supplicant and is also provided as an open-source package.

We update the source and patch as needed to make sure we are up to date on the latest CVEs.

It also goes through our QA validation process with each production release of backports and firmware. For more information, see the release notes on GitHub:

Open/unsecured Network:

network={
        ssid="myAP"
        key_mgmt=NONE
        scan_ssid=1
}

WPA2-PSK:

network={
        ssid="myAP"
        key_mgmt=WPA-PSK
        psk="password"
        pairwise=CCMP
        group=CCMP
        proto=RSN
        scan_ssid=1
}

WPA2-AES with EAP-TLS

network={
    scan_ssid=1
    ssid="myAP"
    pairwise=CCMP
    group=CCMP
    key_mgmt=WPA-EAP
    proto=RSN
    eap=TLS
    identity="user1"
    private_key="/etc/certs/user1.pem"
    private_key_passwd="user1"
    client_cert="/etc/certs/user1.pem"
}

WPA-TKIP with PEAP MSCHAPv2:

network={
    scan_ssid=1
    ssid="myAP"
    key_mgmt=WPA-EAP
    eap=PEAP
    identity="user1"
    phase1="peaplabel=auto peapver=0 "
    phase2="auth=MSCHAPV2"
    password="user1"
}

For the full documentation provided by the wpa_supplicant maintainers, please visit: https://w1.fi/cgit/hostap/plain/wpa_supplicant/wpa_supplicant.conf

The iw tool can be used to read the status of the device:

# iw dev

phy#0
        Unnamed/non-netdev interface
                wdev 0x2
                addr 7e:4a:78:cc:85:77
                type P2P-device
                txpower 31.00 dBm
        Interface wlan0
                ifindex 7
                wdev 0x1
                addr aa:bb:cc:07:0c:b1
                ssid testAP
                type AP
                channel 11 (2462 MHz), width: 20 MHz, center1: 2462 MHz
                txpower 31.00 dBm

Managed/client mode link information:

# iw wlan0 link

Connected to aa:bb:cc:12:34:56 (on wlan0)
        SSID: testAP
        freq: 2462
        RX: 364 bytes (2 packets)
        TX: 3782 bytes (22 packets)
        signal: -31 dBm
        tx bitrate: 2.0 MBit/s
        bss flags:      short-slot-time
        dtim period:    2
        beacon int:     200

AP mode to read connected client information:

# iw wlan0 station dump

Station aa:bb:cc:8b:6c:fe (on wlan0)
        inactive time:  3000 ms
        rx bytes:       6479
        rx packets:     37
        tx bytes:       9706
        tx packets:     66
        tx failed:      0
        signal:         -44 [-44] dBm
        tx bitrate:     1.0 MBit/s
        rx bitrate:     65.0 MBit/s
        authorized:     yes
        authenticated:  yes
        associated:     yes
        WMM/WME:        yes
        TDLS peer:      no
        DTIM period:    2
        beacon interval:100
        short slot time:yes
        connected time: 20 seconds

In BlueZ, some commands such as l2test or l2ping are able to generate traffic on L2CAP layer. To test performance and reliability, you can use the l2test command:

On the server, run the command:

l2test -I 2000 -r

On the client side, run the command:

l2test -O 2000 -s XX:XX:XX:XX:XX:XX

In order to leverage our modular certifications, you must follow the RF design of the module associated with the chip/SIPT. Design files will be provided upon request so you can reproduce our design on your custom board. We highly suggest you to take advantage of our free design review to prevent any issues when going for certification testing.

Please submit a ticket using our support portal when you are ready to begin the process.

We provide custom firmware from Cypress that includes power tables that are only for the LWB Series modules. Using firmware that is not provided by us will violate the modular certifications.

To use an antenna that is not listed on your wireless modules datasheet, it must be of the same topology (e.g. dipole, PIFA, etc.), equal or lesser gain, and have the same in-band and out of band characteristics.

Note: Japan (MIC) lists applicable antennas on its certificates. If your antenna is not on the approved list, regardless of whether it is comparative, it must be added to the certificate before it can be used in Japan.

If you don't want simultaneous ap/sta, you can run the commands:

nmcli conn add type wifi ifname wlan0 con-name softAP autoconnect no ssid softAP

nmcli conn modify softAP 802-11-wireless.mode ap 802-11-wireless.band bg 802-11d

nmcli conn up softAP

You can also do it via wpa_supplicant .conf files if you do not have nmcli.

When the error "can't set line discipline" occurs when the patchram tool is used to bring up the Bluetooth HCI-UART device it is very likely that the "Bluetooth HCI UART" driver (or module) is not enabled in the Linux kernel configuration as module.

Per our agreement with Infineon, formally Cypress, we are required to distribute the testing tools package on an individual basis. To request access, please submit a technical support ticket on our support portal