I would like to know if in the PSoC® 4 BLE if the host part could be disable and use the device just as a BLE controller (Link Layer only). I have a host in a second device and it expects to communicate with the controller via HCI.
Use the DTM mode from the BLE Component. The controller can then be accessed over UART using the HCI commands. The PSoC_4_BLE_DTM/PRoC_BLE_DTM example projects in the BLE Pioneer kit content (www.cypress.com/CY8CKIT-042-BLE) demonstrates this. Refer the user guide of the kit for more details.