[BPI-M4] Problem with Bluetooth after recompile kernel

Hello. I had a problem after recompile Kernel (it need for enable spi). The OS can’t see Wifi and Bluetooth. How I can fix this problem? I follow this instruction - https://github.com/BPI-SINOVOIP/BPI-M4-bsp Thanks a lot for any kind help.

 lsmod
Module                  Size  Used by
8821cu               2645413  0
rtkbt_usb              72994  0


hcitool dev
Devices:

bluetoothctl scan on
No default controller available

 dmesg | grep -Ei 'blue|firm'
[    1.622005] dmi: Firmware registration failed.
[    1.623613] Bluetooth: Core ver 2.22
[    1.623714] Bluetooth: HCI device and connection manager initialized
[    1.623748] Bluetooth: HCI socket layer initialized
[    1.623778] Bluetooth: L2CAP socket layer initialized
[    1.623837] Bluetooth: SCO socket layer initialized
[    5.428471] Bluetooth: RFCOMM TTY layer initialized
[    5.428483] Bluetooth: RFCOMM socket layer initialized
[    5.428517] Bluetooth: RFCOMM ver 1.11
[    5.428530] Bluetooth: BNEP (Ethernet Emulation) ver 1.3
[    5.428533] Bluetooth: BNEP filters: protocol multicast
[    5.428545] Bluetooth: BNEP socket layer initialized
[    5.428549] Bluetooth: HIDP (Human Interface Emulation) ver 1.2
[    5.428558] Bluetooth: HIDP socket layer initialized
[    5.557955] -->rfkill_bluetooth_init
[    5.558197] -->rfkill_bluetooth_probe
[    5.558487] bluetooth_set_power: block=1
[    5.558495] <--rfkill_bluetooth_probe
[   20.801248] bluetooth_set_power: block=1
[  255.594954] rtk_btusb: Realtek Bluetooth USB driver ver 3.1.a2fd257.20190620-164204
[  255.617839] rtk_btusb: load_firmware start
[  255.619028] usb 1-2: Direct firmware load for rtl8821cu_config failed with error -2
[  255.620661] usb 1-2: Direct firmware load for rtl8821cu_fw failed with error -2
[  255.622357] rtk_btusb: load firmware failed!
[  312.645594] RTW: rtl8821c_fw_dl Download Firmware from array success
[  400.967308] bluetooth_set_power: block=0'

If I correctly understand problem with BT_HCI_UART. In basic image BT_HCI_UART was present, after kernel rebuild it was absent. When I tried enable it in config i recive an error.

Make sure 8821cu bluetooth firmware exist in /lib/firmware/