usb: device_next: add BT HCI USB transport layer

Add Bluetooth HCI USB transport layer implementation for the new
experimental USB device support based on the existing implementation
subsys/usb/device/class/bluetooth.c.

This implementation, unlike existing one, contains the interface
descriptors for isochronous endpoints. Since we do not support voice
channels, these are just there to avoid issues with Linux kernel btusb
driver when this implementation is part of a composite configuration.

Signed-off-by: Johann Fischer <[email protected]>

Author: jfischer-no

subsys/usb/device_next/CMakeLists.txt

@@ -31,4 +31,9 @@ zephyr_library_sources_ifdef(
 	class/usbd_cdc_acm.c
 )
 
+zephyr_library_sources_ifdef(
+	CONFIG_USBD_BT_HCI
+	class/bt_hci.c
+)
+
 zephyr_linker_sources(DATA_SECTIONS usbd_data.ld)

subsys/usb/device_next/class/Kconfig

@@ -4,3 +4,4 @@
 
 rsource "Kconfig.loopback"
 rsource "Kconfig.cdc_acm"
+rsource "Kconfig.bt"

subsys/usb/device_next/class/Kconfig.bt

@@ -0,0 +1,35 @@
+# Copyright (c) 2023 Nordic Semiconductor ASA
+# SPDX-License-Identifier: Apache-2.0
+
+config USBD_BT_HCI
+	bool "Bluetooth HCI USB Transport Layer"
+	select BT
+	select BT_HCI_RAW
+	help
+	  Bluetooth HCI USB Transport Layer
+
+if USBD_BT_HCI
+
+config USBD_BT_HCI_TX_THREAD_PRIORITY
+	int "TX thread priority"
+	default 8
+	help
+	  Bluetooth HCI USB Transport Layer TX thread priority.
+
+config USBD_BT_HCI_TX_STACK_SIZE
+	int "TX thread stack size"
+	default 512
+	help
+	  Bluetooth HCI USB Transport Layer TX thread stack size.
+
+config USBD_BT_HCI_RX_THREAD_PRIORITY
+	int "RX thread priority"
+	default 8
+	help
+	  Bluetooth HCI USB Transport Layer RX thread priority.
+
+module = USBD_BT_HCI
+module-str = usbd bt hci
+source "subsys/logging/Kconfig.template.log_config"
+
+endif