Zephyr bluetooth central sample fails with error -EAGAIN

[AndyM]

BT central sample has the following code

bt_enable(NULL);

bt_le_scan_start(SCAN_PASSIVE, device_found);    

I ran the sample on my custom board based on nRF52840 and it always returns -EAGAIN even if I put the bt_le_scan_start in a loop and wait 1000 ms between attempts

I looked in the bt_le_scan_start function in scan.c

It returns -EAGAIN if BT_DEV_READY flag is not set:

if (!atomic_test_bit(bt_dev.flags, BT_DEV_READY)) {

        return -EAGAIN;

    }

Any ideas why this flag is never set? bt_enable does not return an error and is called synchronously

Project settings
-------------------------

CONFIG_BT=y

CONFIG_BT_CENTRAL=y

CONFIG_BT_OBSERVER=y

CONFIG_BT_BROADCASTER=y

CONFIG_BT_MESH=y

CONFIG_BT_MESH_RELAY=y

CONFIG_BT_MESH_SUBNET_COUNT=1

CONFIG_BT_MESH_APP_KEY_COUNT=1

CONFIG_BT_MESH_MODEL_GROUP_COUNT=2

CONFIG_BT_MESH_ADV_BUF_COUNT=10

CONFIG_BT_MESH_LABEL_COUNT=0

CONFIG_BT_MESH_PB_ADV=n

CONFIG_BT_MESH_CFG_CLI=y

CONFIG_BT_MESH_LOOPBACK_BUFS=8

CONFIG_BT_SETTINGS=y

CONFIG_FLASH=y

CONFIG_FLASH_PAGE_LAYOUT=y

CONFIG_FLASH_MAP=y

CONFIG_NVS=y

CONFIG_SETTINGS=y

CONFIG_BT_MESH_RPL_STORE_TIMEOUT=600

--------------------------------------------------------

Thank you

Andy

[AndyM]

Update2

This appears that this has to do with calling bt_enable() from a thread other than main. When bt_enable is called from main the error is gone and all 3 threads that I have run without problems

[Hung Bui]

Hi Andy, 

In my example code I provided you can see that the bt_enable() was called from a thread. So it's pretty strange that in your code it's causing trouble. Maybe you can try to strip down the application to make it more simple to narrow down what may cause the issue ?