| /* |
| * Copyright (c) 2019 Nordic Semiconductor ASA. |
| * |
| * SPDX-License-Identifier: Apache-2.0 |
| */ |
| |
| #include <zephyr/drivers/gpio.h> |
| #include <zephyr/drivers/uart.h> |
| #include <zephyr/device.h> |
| #include <zephyr/devicetree.h> |
| |
| #define RESET_NODE DT_NODELABEL(nrf52840_reset) |
| |
| #if DT_NODE_HAS_STATUS(RESET_NODE, okay) |
| |
| #define RESET_GPIO_CTRL DT_GPIO_CTLR(RESET_NODE, gpios) |
| #define RESET_GPIO_PIN DT_GPIO_PIN(RESET_NODE, gpios) |
| #define RESET_GPIO_FLAGS DT_GPIO_FLAGS(RESET_NODE, gpios) |
| |
| int bt_hci_transport_setup(const struct device *h4) |
| { |
| int err; |
| char c; |
| const struct device *const port = DEVICE_DT_GET(RESET_GPIO_CTRL); |
| |
| if (!device_is_ready(port)) { |
| return -EIO; |
| } |
| |
| /* Configure pin as output and initialize it to inactive state. */ |
| err = gpio_pin_configure(port, RESET_GPIO_PIN, |
| RESET_GPIO_FLAGS | GPIO_OUTPUT_INACTIVE); |
| if (err) { |
| return err; |
| } |
| |
| /* Reset the nRF52840 and let it wait until the pin is inactive again |
| * before running to main to ensure that it won't send any data until |
| * the H4 device is setup and ready to receive. |
| */ |
| err = gpio_pin_set(port, RESET_GPIO_PIN, 1); |
| if (err) { |
| return err; |
| } |
| |
| /* Wait for the nRF52840 peripheral to stop sending data. |
| * |
| * It is critical (!) to wait here, so that all bytes |
| * on the lines are received and drained correctly. |
| */ |
| k_sleep(K_MSEC(10)); |
| |
| /* Drain bytes */ |
| while (h4 && uart_fifo_read(h4, &c, 1)) { |
| continue; |
| } |
| |
| /* We are ready, let the nRF52840 run to main */ |
| err = gpio_pin_set(port, RESET_GPIO_PIN, 0); |
| if (err) { |
| return err; |
| } |
| |
| return 0; |
| } |
| |
| #endif /* DT_NODE_HAS_STATUS(RESET_NODE, okay) */ |
