Unstable Bluetooth operation

[Jamier]

I am using Yocto Kirkstone, with Bluez5 v5.65 and we see that sometimes the bluetooth adapter (Murata lbee5hy1mw)can't be found after a restart.

When it is found and polling some bluetooth devices those devices lose connection after a few days.

So it seems there is something not configured right, or maybe some other problem.

I see in udevadm monitor some concerning messages, but it is hard to tell if this is a real problem or not.

KERNEL[529805.581096] add      /devices/platform/soc@0/30800000.bus/30800000.spba-bus/30890000.serial/tty/ttymxc1/hci0/hci0:64 (bluetooth)
UDEV  [529805.605363] add      /devices/platform/soc@0/30800000.bus/30800000.spba-bus/30890000.serial/tty/ttymxc1/hci0/hci0:64 (bluetooth)

These messages come out very erratically - every few seconds to every few minutes

We've verified that the uart being used by the bluetooth module isn't conflicted with something else. We've tried to disabled power management. Bluetooth does seems to be initialized properly according to dmesg.

Does anyone have a suggestion on what to check next?

[Zhiming_Liu]

Hello,
We've tried to disabled power management. Bluetooth does seems to be initialized properly according to dmesg.

-->The Murata lbee5hy1mw module could have incompatible power management policy with EVK board, or the power management policy on i.MX is not compatible with this bluetooth module. We can't confirm where this abnormal signal from , it could from module or power design. 

I am using Yocto Kirkstone, with Bluez5 v5.65 and we see that sometimes the bluetooth adapter (Murata lbee5hy1mw)can't be found after a restart

-->You can try to check the clock signals and power signals connected with module and board when it restart to check if there is any mismatch.

Best Regards,
Zhiming