usb: device: remove USB H4 Bluetooth function and sample

The Bluetooth HCI USB transport layer implementation is provided by
"subsys/usb/device/class/bluetooth.c". The USB H4 Bluetooth function
implements a non-standard transport layer. There is no known host-side
equivalent that uses this protocol.

Note that the H4 protocol functionality is also provided by the
"subsys/usb/device/class/bluetooth.c".

Since that there are no real USB H4 Bluetooth users, remove the
implementation and sample without deprecation.

Signed-off-by: Johann Fischer <johann.fischer@nordicsemi.no>

doc/connectivity/usb/device/usb_device.rst

@@ -596,7 +596,7 @@ The following Product IDs are currently used:
 +----------------------------------------------------+--------+
 | :zephyr:code-sample:`bluetooth_hci_usb`            | 0x000B |
 +----------------------------------------------------+--------+
-| :zephyr:code-sample:`bluetooth_hci_usb_h4`         | 0x000C |
+| Reserved (previously: bluetooth_hci_usb_h4)        | 0x000C |
 +----------------------------------------------------+--------+
 | Reserved (previously: wpan-usb)                    | 0x000D |
 +----------------------------------------------------+--------+

samples/bluetooth/hci_usb_h4/CMakeLists.txt

@@ -1,7 +0,0 @@
-# SPDX-License-Identifier: Apache-2.0
-
-cmake_minimum_required(VERSION 3.20.0)
-find_package(Zephyr REQUIRED HINTS $ENV{ZEPHYR_BASE})
-project(hci_usb_h4)
-
-target_sources(app PRIVATE src/main.c)

samples/bluetooth/hci_usb_h4/README.rst

@@ -1,25 +0,0 @@
-.. zephyr:code-sample:: bluetooth_hci_usb_h4
-   :name: HCI H4 over USB
-   :relevant-api: hci_raw bluetooth _usb_device_core_api usbd_api
-
-   Turn a Zephyr board into a USB H4 Bluetooth dongle (Linux/BlueZ only).
-
-Overview
-********
-
-Make a USB H4 Bluetooth dongle out of Zephyr. Requires USB device support from
-the board it runs on (e.g. :ref:`nrf52840dk_nrf52840` supports both Bluetooth LE and
-USB).
-
-Requirements
-************
-
-* Bluetooth stack running on the host (e.g. BlueZ)
-* A board with Bluetooth and USB support in Zephyr
-
-Building and Running
-********************
-This sample can be found under :zephyr_file:`samples/bluetooth/hci_usb_h4` in
-the Zephyr tree.
-
-See :zephyr:code-sample-category:`bluetooth` samples for details.

samples/bluetooth/hci_usb_h4/prj.conf

@@ -1,13 +0,0 @@
-CONFIG_STDOUT_CONSOLE=y
-CONFIG_GPIO=y
-CONFIG_SERIAL=y
-CONFIG_UART_INTERRUPT_DRIVEN=y
-CONFIG_USB_DEVICE_INITIALIZE_AT_BOOT=n
-
-CONFIG_USB_DEVICE_STACK=y
-CONFIG_USB_DEVICE_PID=0x000C
-CONFIG_USB_DEVICE_BT_H4=y
-
-# Workaround: Unable to allocate command buffer when using K_NO_WAIT since
-# Host number of completed commands does not follow normal flow control.
-CONFIG_BT_BUF_CMD_TX_COUNT=10

samples/bluetooth/hci_usb_h4/sample.yaml

@@ -1,15 +0,0 @@
-sample:
-  name: Bluetooth over USB sample
-tests:
-  sample.bluetooth.hci_usb_h4:
-    harness: bluetooth
-    depends_on:
-      - usb_device
-      - ble
-    tags:
-      - usb
-      - bluetooth
-    # FIXME: exclude due to build error
-    platform_exclude:
-      - 96b_carbon/stm32f401xe
-      - stm32l562e_dk

samples/bluetooth/hci_usb_h4/src/main.c

@@ -1,23 +0,0 @@
-/*
- * Copyright (c) 2020 Intel Corporation
- *
- * SPDX-License-Identifier: Apache-2.0
- */
-
-#include <zephyr/kernel.h>
-#include <zephyr/sys/printk.h>
-#include <zephyr/usb/usb_device.h>
-
-int main(void)
-{
-	int ret;
-
-	ret = usb_enable(NULL);
-	if (ret != 0) {
-		printk("Failed to enable USB");
-		return 0;
-	}
-
-	printk("Bluetooth H:4 over USB sample\n");
-	return 0;
-}

subsys/usb/device/class/CMakeLists.txt

@@ -3,7 +3,6 @@
 zephyr_sources_ifdef(CONFIG_USB_CDC_ACM cdc_acm.c)
 zephyr_sources_ifdef(CONFIG_USB_MASS_STORAGE msc.c)
 zephyr_sources_ifdef(CONFIG_USB_DEVICE_BLUETOOTH bluetooth.c)
-zephyr_sources_ifdef(CONFIG_USB_DEVICE_BT_H4 bt_h4.c)
 zephyr_sources_ifdef(CONFIG_USB_DEVICE_LOOPBACK loopback.c)
 
 add_subdirectory_ifdef(CONFIG_USB_DEVICE_AUDIO audio)

subsys/usb/device/class/Kconfig.bt

@@ -16,12 +16,3 @@ config USB_DEVICE_BLUETOOTH_VS_H4
 	help
 	  Enables vendor command to switch to H:4 transport using the bulk
 	  endpoint.
-
-config USB_DEVICE_BT_H4
-	bool "USB Bluetooth H4 Device Class support"
-	select BT
-	select BT_HCI_RAW
-	select BT_HCI_RAW_H4
-	select BT_HCI_RAW_H4_ENABLE
-	help
-	  USB Bluetooth H4 device class support

subsys/usb/device/class/bt_h4.c

@@ -1,261 +0,0 @@
-/*
- * Wireless / Bluetooth USB class
- *
- * Copyright (c) 2020 Intel Corporation
- *
- * SPDX-License-Identifier: Apache-2.0
- */
-
-#include <zephyr/init.h>
-#include <zephyr/sys/byteorder.h>
-
-#include <zephyr/usb/usb_device.h>
-#include <usb_descriptor.h>
-
-#include <zephyr/net_buf.h>
-
-#include <zephyr/bluetooth/buf.h>
-#include <zephyr/bluetooth/hci_raw.h>
-#include <zephyr/bluetooth/l2cap.h>
-
-#include <zephyr/logging/log.h>
-LOG_MODULE_REGISTER(usb_bt_h4, CONFIG_USB_DEVICE_LOG_LEVEL);
-
-static K_FIFO_DEFINE(rx_queue);
-static K_FIFO_DEFINE(tx_queue);
-
-#define BT_H4_OUT_EP_ADDR               0x01
-#define BT_H4_IN_EP_ADDR                0x81
-
-#define BT_H4_OUT_EP_IDX                0
-#define BT_H4_IN_EP_IDX                 1
-
-/* HCI RX/TX threads */
-static K_KERNEL_STACK_DEFINE(rx_thread_stack, CONFIG_BT_RX_STACK_SIZE);
-static struct k_thread rx_thread_data;
-static K_KERNEL_STACK_DEFINE(tx_thread_stack, CONFIG_BT_HCI_TX_STACK_SIZE);
-static struct k_thread tx_thread_data;
-
-/* HCI USB state flags */
-static bool configured;
-static bool suspended;
-
-struct usb_bt_h4_config {
-	struct usb_if_descriptor if0;
-	struct usb_ep_descriptor if0_out_ep;
-	struct usb_ep_descriptor if0_in_ep;
-} __packed;
-
-USBD_CLASS_DESCR_DEFINE(primary, 0) struct usb_bt_h4_config bt_h4_cfg = {
-	/* Interface descriptor 0 */
-	.if0 = {
-		.bLength = sizeof(struct usb_if_descriptor),
-		.bDescriptorType = USB_DESC_INTERFACE,
-		.bInterfaceNumber = 0,
-		.bAlternateSetting = 0,
-		.bNumEndpoints = 2,
-		.bInterfaceClass = USB_BCC_VENDOR, /* TBD */
-		.bInterfaceSubClass = 0,
-		.bInterfaceProtocol = 0,
-		.iInterface = 0,
-	},
-
-	/* Data Endpoint OUT */
-	.if0_out_ep = {
-		.bLength = sizeof(struct usb_ep_descriptor),
-		.bDescriptorType = USB_DESC_ENDPOINT,
-		.bEndpointAddress = BT_H4_OUT_EP_ADDR,
-		.bmAttributes = USB_DC_EP_BULK,
-		.wMaxPacketSize = sys_cpu_to_le16(USB_MAX_FS_BULK_MPS),
-		.bInterval = 0x01,
-	},
-
-	/* Data Endpoint IN */
-	.if0_in_ep = {
-		.bLength = sizeof(struct usb_ep_descriptor),
-		.bDescriptorType = USB_DESC_ENDPOINT,
-		.bEndpointAddress = BT_H4_IN_EP_ADDR,
-		.bmAttributes = USB_DC_EP_BULK,
-		.wMaxPacketSize = sys_cpu_to_le16(USB_MAX_FS_BULK_MPS),
-		.bInterval = 0x01,
-	},
-};
-
-static struct usb_ep_cfg_data bt_h4_ep_data[] = {
-	{
-		.ep_cb = usb_transfer_ep_callback,
-		.ep_addr = BT_H4_OUT_EP_ADDR,
-	},
-	{
-		.ep_cb = usb_transfer_ep_callback,
-		.ep_addr = BT_H4_IN_EP_ADDR,
-	},
-};
-
-static void bt_h4_read(uint8_t ep, int size, void *priv)
-{
-	static uint8_t data[USB_MAX_FS_BULK_MPS];
-
-	if (size > 0) {
-		struct net_buf *buf;
-
-		buf = bt_buf_get_tx(BT_BUF_H4, K_FOREVER, data, size);
-		if (!buf) {
-			LOG_ERR("Cannot get free TX buffer\n");
-			return;
-		}
-
-		k_fifo_put(&rx_queue, buf);
-	}
-
-	/* Start a new read transfer */
-	usb_transfer(bt_h4_ep_data[BT_H4_OUT_EP_IDX].ep_addr, data,
-		     USB_MAX_FS_BULK_MPS, USB_TRANS_READ, bt_h4_read, NULL);
-}
-
-static void hci_tx_thread(void *p1, void *p2, void *p3)
-{
-	ARG_UNUSED(p1);
-	ARG_UNUSED(p2);
-	ARG_UNUSED(p3);
-
-	LOG_DBG("Start USB Bluetooth thread");
-
-	while (true) {
-		struct net_buf *buf;
-
-		buf = k_fifo_get(&tx_queue, K_FOREVER);
-
-		usb_transfer_sync(bt_h4_ep_data[BT_H4_IN_EP_IDX].ep_addr,
-				  buf->data, buf->len, USB_TRANS_WRITE);
-
-		net_buf_unref(buf);
-	}
-}
-
-static void hci_rx_thread(void *p1, void *p2, void *p3)
-{
-	ARG_UNUSED(p1);
-	ARG_UNUSED(p2);
-	ARG_UNUSED(p3);
-
-	while (true) {
-		struct net_buf *buf;
-
-		buf = k_fifo_get(&rx_queue, K_FOREVER);
-		if (bt_send(buf)) {
-			LOG_ERR("Error sending to driver");
-			net_buf_unref(buf);
-		}
-	}
-}
-
-static void bt_h4_status_cb(struct usb_cfg_data *cfg,
-			    enum usb_dc_status_code status, const uint8_t *param)
-{
-	ARG_UNUSED(cfg);
-
-	/* Check the USB status and do needed action if required */
-	switch (status) {
-	case USB_DC_RESET:
-		LOG_DBG("Device reset detected");
-		suspended = false;
-		configured = false;
-		break;
-	case USB_DC_CONFIGURED:
-		LOG_DBG("Device configured");
-		if (!configured) {
-			configured = true;
-			/* Start reading */
-			bt_h4_read(bt_h4_ep_data[BT_H4_OUT_EP_IDX].ep_addr,
-				   0, NULL);
-		}
-		break;
-	case USB_DC_DISCONNECTED:
-		LOG_DBG("Device disconnected");
-		/* Cancel any transfer */
-		usb_cancel_transfer(bt_h4_ep_data[BT_H4_IN_EP_IDX].ep_addr);
-		usb_cancel_transfer(bt_h4_ep_data[BT_H4_OUT_EP_IDX].ep_addr);
-		suspended = false;
-		configured = false;
-		break;
-	case USB_DC_SUSPEND:
-		suspended = true;
-		break;
-	case USB_DC_RESUME:
-		LOG_DBG("Device resumed");
-		if (suspended) {
-			LOG_DBG("from suspend");
-			suspended = false;
-		} else {
-			LOG_DBG("Spurious resume event");
-		}
-		break;
-	case USB_DC_UNKNOWN:
-	default:
-		LOG_DBG("Unhandled status: %u", status);
-		break;
-	}
-}
-
-static int bt_h4_vendor_handler(struct usb_setup_packet *setup,
-				int32_t *len, uint8_t **data)
-{
-	LOG_DBG("Class request: bRequest 0x%x bmRequestType 0x%x len %d",
-		setup->bRequest, setup->bmRequestType, *len);
-
-	return -ENOTSUP;
-}
-
-static void bt_h4_interface_config(struct usb_desc_header *head,
-				   uint8_t bInterfaceNumber)
-{
-	ARG_UNUSED(head);
-
-	bt_h4_cfg.if0.bInterfaceNumber = bInterfaceNumber;
-}
-
-USBD_DEFINE_CFG_DATA(bt_h4_config) = {
-	.usb_device_description = NULL,
-	.interface_config = bt_h4_interface_config,
-	.interface_descriptor = &bt_h4_cfg.if0,
-	.cb_usb_status = bt_h4_status_cb,
-	.interface = {
-		.class_handler = NULL,
-		.custom_handler = NULL,
-		.vendor_handler = bt_h4_vendor_handler,
-	},
-	.num_endpoints = ARRAY_SIZE(bt_h4_ep_data),
-	.endpoint = bt_h4_ep_data,
-};
-
-static int bt_h4_init(void)
-{
-	int ret;
-
-	LOG_DBG("Initialization");
-
-	ret = bt_enable_raw(&tx_queue);
-	if (ret) {
-		LOG_ERR("Failed to open Bluetooth raw channel: %d", ret);
-		return ret;
-	}
-
-	k_thread_create(&rx_thread_data, rx_thread_stack,
-			K_KERNEL_STACK_SIZEOF(rx_thread_stack),
-			hci_rx_thread, NULL, NULL, NULL,
-			K_PRIO_COOP(8), 0, K_NO_WAIT);
-
-	k_thread_name_set(&rx_thread_data, "usb_bt_h4_rx");
-
-	k_thread_create(&tx_thread_data, tx_thread_stack,
-			K_KERNEL_STACK_SIZEOF(tx_thread_stack),
-			hci_tx_thread, NULL, NULL, NULL,
-			K_PRIO_COOP(8), 0, K_NO_WAIT);
-
-	k_thread_name_set(&tx_thread_data, "usb_bt_h4_tx");
-
-	return 0;
-}
-
-SYS_INIT(bt_h4_init, APPLICATION, CONFIG_KERNEL_INIT_PRIORITY_DEVICE);