Most of the bluetooth and wifi chips appear to need external firmware, and the 43438 is no exception. Fortunately, since Cypress got involved, these are much more straightforward to obtain and are shipped as part of their SDK, which is downloadable from their website. Those firmwares are already provided as C arrays, so their names just need updating to;
const unsigned char bt_firmware_hcd -> The bt firmware array.
const int bt_firmware_len = sizeof(bt_firmware_hcd);
Squashed commit of the following:
drivers/bluetooth: Re-architect Bluetooth UART driver to follow upper/lower half model. Completely untested.
drivers/bluetooth: Grr.. Another band-aid commit to stay in sync with master. Why is this so difficult
drivers/bluetooth: Band-aid commit to stay in sync with master. Lost it somehow.
drivers/wireless/bluetooth: A few changes, mostly thought experiments.
drivers/wireless/bluetooth: UART-based Bluetooth driver ported from the Intel/Zephyr arduino101_firmware_source-v1.tar package. This initial commit is the original files in the NuttX build environment with changes to conform with the coding standard. It should not even build.