drivers: bluetooth: hci: add hardware reset for da1453x

Add ability to perform a hardware reset of the DA1453x during setup of
the HCI transport.

Signed-off-by: Ian Morris <ian.d.morris@outlook.com>

drivers/bluetooth/hci/CMakeLists.txt

@@ -29,6 +29,7 @@ if(CONFIG_DT_HAS_INFINEON_CAT1_BLESS_HCI_ENABLED)
 endif()
 zephyr_library_sources_ifdef(CONFIG_SOC_NRF5340_CPUAPP nrf53_support.c)
 zephyr_library_sources_ifdef(CONFIG_BT_AMBIQ_HCI   hci_ambiq.c apollox_blue.c)
+zephyr_library_sources_ifdef(CONFIG_BT_DA1453X     hci_da1453x.c)
 zephyr_library_sources_ifdef(CONFIG_BT_DA1469X     hci_da1469x.c)
 zephyr_library_sources_ifdef(CONFIG_BT_NXP         hci_nxp.c)
 zephyr_library_sources_ifdef(CONFIG_BT_H4_NXP_CTLR hci_nxp_setup.c)

drivers/bluetooth/hci/Kconfig

@@ -160,6 +160,15 @@ config BT_PSOC6_BLESS
 	  PSOC 6 BLESS driver with BLE Controller which operates in
 	  Single CPU mode.
 
+config BT_DA1453X
+	bool "DA1453x HCI driver"
+	default y
+	depends on DT_HAS_RENESAS_BT_HCI_DA1453X_ENABLED
+	select GPIO
+	help
+	  Bluetooth HCI driver for communication with controller
+	  running on DA1453x MCU.
+
 config BT_DA1469X
 	bool
 	default y

drivers/bluetooth/hci/hci_da1453x.c

@@ -0,0 +1,59 @@
+/*
+ * Copyright 2024 Ian Morris
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <zephyr/kernel.h>
+#include <zephyr/device.h>
+#include <zephyr/devicetree.h>
+#include <zephyr/drivers/gpio.h>
+#include <zephyr/drivers/uart.h>
+
+#define LOG_LEVEL CONFIG_BT_HCI_DRIVER_LOG_LEVEL
+#include <zephyr/logging/log.h>
+LOG_MODULE_REGISTER(bt_hci_da1453x);
+
+#define DT_DRV_COMPAT renesas_bt_hci_da1453x
+
+int bt_hci_transport_setup(const struct device *h4)
+{
+	int err = 0;
+
+#if DT_INST_NODE_HAS_PROP(0, reset_gpios)
+	char c;
+	struct gpio_dt_spec bt_reset = GPIO_DT_SPEC_GET(DT_DRV_INST(0), reset_gpios);
+
+	if (!gpio_is_ready_dt(&bt_reset)) {
+		LOG_ERR("Error: failed to configure bt_reset %s pin %d", bt_reset.port->name,
+			bt_reset.pin);
+		return -EIO;
+	}
+
+	/* Set bt_reset as output and activate DA1453x reset */
+	err = gpio_pin_configure_dt(&bt_reset, GPIO_OUTPUT_ACTIVE);
+	if (err) {
+		LOG_ERR("Error %d: failed to configure bt_reset %s pin %d", err,
+			bt_reset.port->name, bt_reset.pin);
+		return err;
+	}
+
+	k_sleep(K_MSEC(DT_INST_PROP_OR(0, reset_assert_duration_ms, 0)));
+
+	/* Release the DA1453x from reset */
+	err = gpio_pin_set_dt(&bt_reset, 0);
+	if (err) {
+		return err;
+	}
+
+	/* Wait for the DA1453x to boot */
+	k_sleep(K_MSEC(DT_INST_PROP(0, boot_duration_ms)));
+
+	/* Drain bytes */
+	while (h4 && uart_fifo_read(h4, &c, 1)) {
+		continue;
+	}
+#endif /* DT_INST_NODE_HAS_PROP(0, reset_gpios) */
+
+	return err;
+}

dts/bindings/bluetooth/renesas,bt-hci-da1453x.yaml

@@ -0,0 +1,28 @@
+# Copyright 2024 Ian Morris
+# SPDX-License-Identifier: Apache-2.0
+
+description: |
+  Extension of the Bluetooth H:4 HCI driver for a Renesas DA1453x based
+  controller, allowing control of the GPIO used to reset the DA1453x.
+
+compatible: "renesas,bt-hci-da1453x"
+
+include: base.yaml
+
+properties:
+  reset-gpios:
+    type: phandle-array
+    description: |
+      This gpio is used to reset the DA1453x.
+
+  reset-assert-duration-ms:
+    type: int
+    description: |
+      Minimum duration to activate the reset-gpios pin.
+      If not specified no delay beyond the code path execution time is guaranteed.
+
+  boot-duration-ms:
+    type: int
+    default: 200
+    description: |
+      Minimum time to wait for the DA1453x to boot following a hardware reset.