5.11: Bluetooth adapter doesn't get up

On 5.11, the Bluetooth adapter never gets up:

purism@dogwood:~$ sudo hciconfig
hci0:   Type: Primary  Bus: SDIO
        BD Address: XX:XX:XX:XX:XX:XX  ACL MTU: 1021:3  SCO MTU: 64:3
        DOWN 
        RX bytes:1118 acl:0 sco:0 events:56 errors:0
        TX bytes:0 acl:0 sco:0 commands:56 errors:0

purism@dogwood:~$ sudo hciconfig hci0 up
Can't init device hci0: Invalid request code (56)

[   13.898879] redpine_91x: rsi_send_bt_reg_params: Sending BT reg frame
[   13.905411] BT REG PARAMS: (length = 21)
[   13.913202] 05 60 00 00 00 00 00 00 00 00 00 00 00 00 55 00 
[   13.919241] 00 00 01 1e 02 
[   13.922919] redpine_91x:  HCI module init done...
[   13.930868] redpine_91x: RSI HCI DEVICE "hci0" open
[   14.949940] redpine_91x: RSI `hci0' flush
[   14.957680] redpine_91x: RSI HCI DEVICE "hci0" closed
[   14.962896] redpine_91x: rsi_hci_close: device `hci0' not running

Note that this does not seem related to the updated driver: it works fine on 5.9 with the same driver applied.