zephyr/subsys/bluetooth/controller/coex
Gerard Marull-Paretas 4f80e50b55 bluetooth: controller: coex: convert to DT device
Convert the driver to a dt-based device. Also update Kconfig so that it
depends on the right compatible being enabled, initialize in POST_KERNEL
(APPLICATION should not be used for devices) and remove one redundant
include.

Signed-off-by: Gerard Marull-Paretas <gerard@teslabs.com>
2023-09-15 16:04:19 +02:00
..
CMakeLists.txt
Kconfig
coex_ticker.c
readme.rst

readme.rst

******************************
Bluetooth co-existence drivers
******************************

Co-existence Ticker
###################

Implementation :file:`coex_ticker.c` is designed to utilize co-existence with another transmitter. Chips such as nordic nRF9160 provide a 1-wire co-existence interface, which allows the Bluetooth controller to suspend its activity until the other transceiver suspends its operation.

Nordic connect SDK provides detailed description of the 1-wire and 3-wire co-existence interface for the `SoftDevice Bluetooth controller <https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/nrfxlib/mpsl/doc/bluetooth_coex.html>`_

Similarly, as in the nordic implementation of the 1-wire interface, the coexistence ticker utilizes a single pin called BLE_GRANT, which active level (high or low) is programmable by the device tree definition.

.. code-block:: DTS

    coex_gpio: coex {
        compatible = "gpio-radio-coex";
        grant-gpios = <&gpio0 0 (GPIO_PULL_DOWN | GPIO_ACTIVE_HIGH)>;
        grant-delay-us = <150>;
    };

Whenever the grant pin transitions into non-active (such as 1 for the nRF9160). state the implementation starts a ticker job, which in predefined intervals cancels any radio events. This way all advertisements and other radioactivities are suspended until the grant pin transitions into an active state.