Bluetooth doesn't appear after boot very often in Orange Pi 2W

[sminder]

I've got Orange Pi 2W board and installed Debian 12 Home Assistant image to it (image link). There is a huge problem with it. Very often there is no bluetooth module appeared in system. I need to reboot system for 10-15 timer to make it work. What can be a reason?

I attached 2 boot logs (with good BT appears and no BT appears), I hope it will help to find out the issue.

 

boot_log_bt_good_02.zip

boot_log_bt_bad_02.zip

[IBV]

Hi,

 

without owning this board, chatgpt is pointing out to an initialisation issue of the bluetooth system caused by the GPIO pin not being correctly handled at boot.

 [    6.024062] WCN: marlin chip en dummy pull up -- need manually set GPIO 

The correct solution would be to handle the init in the dtb file, but you can try the following systemd initialisation as a workaround to see if it works.

 

Create (as root) the following service file /etc/systemd/system/bt-gpio.service with the contents:

[Unit]
Description=Enable GPIO for Bluetooth chip
Before=bluetooth.service

[Service]
Type=oneshot
ExecStart=/bin/sh -c 'echo 225 > /sys/class/gpio/export || true; echo out > /sys/class/gpio/gpio225/direction; echo 1 > /sys/class/gpio/gpio225/value'

[Install]
WantedBy=multi-user.target

Then enable it (as root):

systemctl daemon-reexec
systemctl daemon-reload
systemctl enable bt-gpio.service

Reboot and check if the bluetooth starts correctly. Post the boot log if it does not.

 

[Michael Robinson]

Also Check your PSU if the problem is intermittent.

[sminder]

Thank you for the suggestion. Unfortunately, it didn't help. Here is a boot log after your fix:

bt_boot_fail_after_fix.txt

[IBV]

I did not see the bt-gpio service starting on boot.

Can you post the status ?

 

On 6/9/2025 at 8:28 AM, IBV said:

systemctl status bt-gpio.service

 

[sminder]

user@orangepizero2w:~$ systemctl status bt-gpio.service
× bt-gpio.service - Enable GPIO for Bluetooth chip
     Loaded: loaded (/etc/systemd/system/bt-gpio.service; enabled; preset: enabled)
     Active: failed (Result: exit-code) since Tue 2025-06-10 23:18:23 +03; 11h ago
    Process: 489 ExecStart=/bin/sh -c echo 225 > /sys/class/gpio/export || true; echo out > /sys/class/gpio/gpio225/direction; echo 1 > /sys/class/gpio/gpio225/value (code=exited, status=2)
   Main PID: 489 (code=exited, status=2)
        CPU: 5ms

jun 10 23:18:23 orangepizero2w systemd[1]: Starting bt-gpio.service - Enable GPIO for Bluetooth chip...
jun 10 23:18:23 orangepizero2w sh[489]: /bin/sh: 1: echo: echo: I/O error
jun 10 23:18:23 orangepizero2w sh[489]: /bin/sh: 1: cannot create /sys/class/gpio/gpio225/direction: Directory nonexistent
jun 10 23:18:23 orangepizero2w sh[489]: /bin/sh: 1: cannot create /sys/class/gpio/gpio225/value: Directory nonexistent
jun 10 23:18:23 orangepizero2w systemd[1]: bt-gpio.service: Main process exited, code=exited, status=2/INVALIDARGUMENT
jun 10 23:18:23 orangepizero2w systemd[1]: bt-gpio.service: Failed with result 'exit-code'.
jun 10 23:18:23 orangepizero2w systemd[1]: Failed to start bt-gpio.service - Enable GPIO for Bluetooth chip.

 

Also I attached boot log which is connected to that "systemctl status bt-gpio.service" command.

 

bt_fail_boot_log_3.txt

 

 

When the board was boot correctly (BT is working fine) the output looks the same:

user@orangepizero2w:~$ systemctl status bt-gpio.service
× bt-gpio.service - Enable GPIO for Bluetooth chip
     Loaded: loaded (/etc/systemd/system/bt-gpio.service; enabled; preset: enabled)
     Active: failed (Result: exit-code) since Wed 2025-06-11 11:04:21 +03; 1min 30s ago
    Process: 492 ExecStart=/bin/sh -c echo 225 > /sys/class/gpio/export || true; echo out > /sys/class/gpio/gpio225/direction; echo 1 > /sys/class/gpio/gpio225/value (code=exited, status=2)
   Main PID: 492 (code=exited, status=2)
        CPU: 5ms

jun 11 11:04:21 orangepizero2w systemd[1]: Starting bt-gpio.service - Enable GPIO for Bluetooth chip...
jun 11 11:04:21 orangepizero2w sh[492]: /bin/sh: 1: echo: echo: I/O error
jun 11 11:04:21 orangepizero2w sh[492]: /bin/sh: 1: cannot create /sys/class/gpio/gpio225/direction: Directory nonexistent
jun 11 11:04:21 orangepizero2w sh[492]: /bin/sh: 1: cannot create /sys/class/gpio/gpio225/value: Directory nonexistent
jun 11 11:04:21 orangepizero2w systemd[1]: bt-gpio.service: Main process exited, code=exited, status=2/INVALIDARGUMENT
jun 11 11:04:21 orangepizero2w systemd[1]: bt-gpio.service: Failed with result 'exit-code'.
jun 11 11:04:21 orangepizero2w systemd[1]: Failed to start bt-gpio.service - Enable GPIO for Bluetooth chip.

 

[IBV]

Can you post your /boot/armbianEnv.txt ?

[sminder]

Sure.

 

armbianEnv.txt

[IBV]

sudo armbian-config

Are you able to see the below overlays ? If yes, activate them.

System → Hardware/Kernel → Activate UART0, UART1, BT overlays

[sminder]

I don't see such interfaces. Could you point me if one of these are suitable?

 

[IBV]

Difficult to see like this, better list the overlay directory:

 

ls /boot/dtb/overlays

 

[sminder]

ls: unable to get access to '/boot/dtb/overlays': No such file or directory.

 

Despite this, I attached full tree of "boot" directory.

 

boot_dir_content.txt

Edited yesterday at 01:23 PM by sminder

[IBV]

Ok,

 

if you want we can try one more thing. According to AI, the correct way to always enable the bluetooth is to do it via a custom overlay, which is not done.

 

First, remove the bt-gpio.service, it does not help:

sudo sytemctl disable bt-gpio.service
sudo rm /etc/systemd/system/bt-gpio.service
sudo systemctl daemon-reload 

 

Then, create the custom overlay file /boot/overlay-user/bt_enable_ph1.dts with the following content:

/dts-v1/;
/plugin/;

&pio {
    bt_en_pin: bt_en_pin {
        pins = "PH1";
        function = "gpio_out";
        bias-pull-up;
        output-high;
    };
};

&uart0 {
    pinctrl-names = "default";
    pinctrl-0 = <&uart0_pins>;
    status = "okay";
};

&wcn_bt {
    compatible = "wcn,bt";
    uart = <&uart0>;
    enable-gpios = <&pio 7 1 GPIO_ACTIVE_HIGH>;  // PH1 = GPIO 225
    status = "okay";
};

Then we can try to compile and install it:

sudo armbian-add-overlay /boot/overlay-user/bt_enable_ph1.dts

Then activate it in /boot/armbianEnv.txt, add the following line:

user_overlays=bt_enable_ph1

If all works well try to reboot and see what happens.

 

[sminder]

sudo armbian-add-overlay /boot/overlay-user/bt_enable_ph1.dts
Compiling the overlay
Error: /boot/overlay-user/bt_enable_ph1.dts:22.30-31 syntax error
FATAL ERROR: Unable to parse input tree
Error compiling the overlay

 

Unfortunately, I didn't understand what the error is.

[IBV]

Ok, replace the contents of the dts file with this:

/dts-v1/;
/plugin/;

/ {
    fragment@0 {
        target = <&pio>;
        __overlay__ {
            bt_enable_pin: bt_enable_pin {
                pins = "PH1";
                function = "gpio_out";
                bias-pull-up;
                output-high;
            };
        };
    };
};

And try again the steps

[sminder]

That was successful. Unfortunately, the fail rate not too much better than as I added new service: one boot was good, one was bad. Here is a log of the fail boot.

 

bt_boot_fail_after_new_devicetree.txt

[IBV]

Ok,

 

create a new dts /boot/overlay-user/bt_enable_full.dts

 

/dts-v1/;
/plugin/;

&pio {
    bt_en_pin: bt_en_pin {
        pins = "PH1";
        function = "gpio_out";
        bias-pull-up;
        output-high;
    };

    bt_wake_pin: bt_wake_pin {
        pins = "PH0";
        function = "gpio_in";
        bias-pull-up;
    };
};

&{/soc} {
    wcn_bt: wcn_bt@0 {
        compatible = "wcn,bt";
        status = "okay";
        enable-gpios = <&pio 7 1 GPIO_ACTIVE_HIGH>; // PH1 = GPIO225
        wake-gpios = <&pio 7 0 GPIO_ACTIVE_HIGH>;   // PH0 = GPIO224 (if connected)
    };
};

And compile it:

sudo armbian-add-overlay /boot/overlay-user/bt_enable_full.dts

Then enable it in /boot/armbianEnv.txt

user_overlays=bt_enable_full

See if there's an improvement on boot.

[sminder]

sudo armbian-add-overlay /boot/overlay-user/bt_enable_full.dts
Compiling the overlay
Error: /boot/overlay-user/bt_enable_full.dts:23.34-35 syntax error
FATAL ERROR: Unable to parse input tree
Error compiling the overlay

 

 Ok, I guess the problem was in "GPIO_ACTIVE_HIGH" macros. So I changed them to "1". File has compiled and I begun to test the board.

Two times in row the board booted ok, but next time BT has failed.

[IBV]

Interesting, pls post the failed boot.

[sminder]

bt_boot_fail_04.txt

[IBV]

Ok, try with this dts file /boot/overlay-user/bt_enable_clean.dts

/dts-v1/;
/plugin/;

&pio {
    bt_en_pin: bt_en_pin {
        pins = "PH1";                  // GPIO225
        function = "gpio_out";
        bias-pull-up;
        drive-strength = <20>;
        output-high;
    };
};

Compile it:

sudo armbian-add-overlay /boot/overlay-user/bt_enable_clean.dts

and enable it in /boot/armbianEnv.txt

user_overlays=bt_enable_clean

Then see if better on reboot.