USB Host: integrate class API [2: helpers]

include/zephyr/drivers/usb/uhc.h

@@ -54,11 +54,16 @@ enum usb_device_speed {
 #define UHC_INTERFACES_MAX 32
 
 struct usb_host_interface {
+	/** Pointer to the interface descriptor */
 	struct usb_desc_header *dhp;
+	/** Pointer to the association interface descriptor, if any */
+	struct usb_association_descriptor *iad;
+	/** Alternate setting selected for this interface */
 	uint8_t alternate;
 };
 
 struct usb_host_ep {
+	/** Pointer to the endpoint descriptor */
 	struct usb_ep_descriptor *desc;
 };
 

include/zephyr/usb/usbh.h

@@ -1,6 +1,6 @@
 /*
- * Copyright (c) 2022 Nordic Semiconductor ASA
- *
+ * SPDX-FileCopyrightText: Copyright Nordic Semiconductor ASA
+ * SPDX-FileCopyrightText: Copyright 2025 NXP
  * SPDX-License-Identifier: Apache-2.0
  */
 
@@ -17,6 +17,7 @@
 #include <stdint.h>
 #include <zephyr/device.h>
 #include <zephyr/net_buf.h>
+#include <zephyr/sys/util.h>
 #include <zephyr/sys/dlist.h>
 #include <zephyr/sys/bitarray.h>
 #include <zephyr/drivers/usb/uhc.h>
@@ -33,6 +34,16 @@ extern "C" {
  * @{
  */
 
+/**
+ * USB host support status
+ */
+struct usbh_status {
+	/** USB host support is initialized */
+	unsigned int initialized : 1;
+	/** USB host support is enabled */
+	unsigned int enabled : 1;
+};
+
 /**
  * USB host support runtime context
  */
@@ -43,6 +54,8 @@ struct usbh_context {
 	struct k_mutex mutex;
 	/** Pointer to UHC device struct */
 	const struct device *dev;
+	/** Status of the USB host support */
+	struct usbh_status status;
 	/** USB device list */
 	sys_dlist_t udevs;
 	/** USB root device */
@@ -60,47 +73,120 @@ struct usbh_context {
 		.addr_ba = &ba_##device_name,				\
 	}
 
+struct usbh_class_data;
+
 /**
- * @brief USB Class Code triple
+ * @brief Information about a device, which is relevant for matching a particular class.
  */
-struct usbh_code_triple {
-	/** Device Class Code */
-	uint8_t dclass;
-	/** Class Subclass Code */
+struct usbh_class_filter {
+	/** Vendor ID */
+	uint16_t vid;
+	/** Product ID */
+	uint16_t pid;
+	/** Class Code */
+	uint8_t class;
+	/** Subclass Code */
 	uint8_t sub;
-	/** Class Protocol Code */
+	/** Protocol Code */
 	uint8_t proto;
+	/** Flags that tell which field to match */
+	uint8_t flags;
 };
 
 /**
- * @brief USB host class data and class instance API
+ * @brief USB host class instance API
+ */
+struct usbh_class_api {
+	/** Host initialization handler, before any device is connected */
+	int (*init)(struct usbh_class_data *const c_data,
+		    struct usbh_context *const uhs_ctx);
+	/** Request completion handler */
+	int (*completion_cb)(struct usbh_class_data *const c_data,
+			     struct uhc_transfer *const xfer);
+	/** Device connection handler */
+	int (*probe)(struct usbh_class_data *const c_data,
+		     struct usb_device *const udev,
+		     const uint8_t iface);
+	/** Device removal handler */
+	int (*removed)(struct usbh_class_data *const c_data);
+	/** Bus suspended handler (optional) */
+	int (*suspended)(struct usbh_class_data *const c_data);
+	/** Bus resumed handler (optional) */
+	int (*resumed)(struct usbh_class_data *const c_data);
+};
+
+/**
+ * @brief USB host class instance data
  */
 struct usbh_class_data {
-	/** Class code supported by this instance */
-	struct usbh_code_triple code;
-
-	/** Initialization of the class implementation */
-	/* int (*init)(struct usbh_context *const uhs_ctx); */
-	/** Request completion event handler */
-	int (*request)(struct usbh_context *const uhs_ctx,
-			struct uhc_transfer *const xfer, int err);
-	/** Device connected handler  */
-	int (*connected)(struct usbh_context *const uhs_ctx);
-	/** Device removed handler  */
-	int (*removed)(struct usbh_context *const uhs_ctx);
-	/** Bus remote wakeup handler  */
-	int (*rwup)(struct usbh_context *const uhs_ctx);
-	/** Bus suspended handler  */
-	int (*suspended)(struct usbh_context *const uhs_ctx);
-	/** Bus resumed handler  */
-	int (*resumed)(struct usbh_context *const uhs_ctx);
+	/** Name of the USB host class instance */
+	const char *name;
+	/** Pointer to USB host stack context structure */
+	struct usbh_context *uhs_ctx;
+	/** Pointer to USB device this class is used for */
+	struct usb_device *udev;
+	/** First interface number or claimed function */
+	uint8_t iface;
+	/** Pointer to host support class API */
+	struct usbh_class_api *api;
+	/** Pointer to private data */
+	void *priv;
 };
 
 /**
+ * @cond INTERNAL_HIDDEN
+ *
+ * Internal state of an USB class. Not corresponding to an USB protocol state,
+ * but instead software life cycle.
  */
-#define USBH_DEFINE_CLASS(name) \
-	static STRUCT_SECTION_ITERABLE(usbh_class_data, name)
+enum usbh_class_state {
+	/** The class is available to be associated to an USB device function. */
+	USBH_CLASS_STATE_IDLE,
+	/** The class got bound to an USB function of a particular device on the bus. */
+	USBH_CLASS_STATE_BOUND,
+	/** The class failed to initialize and cannot be used. */
+	USBH_CLASS_STATE_ERROR,
+};
+/* @endcond */
 
+/**
+ * @cond INTERNAL_HIDDEN
+ *
+ * Variables used by the USB host stack but not exposed to the class
+ * through the class API.
+ */
+struct usbh_class_node {
+	/** Class information exposed to host class implementations (drivers). */
+	struct usbh_class_data *const c_data;
+	/** Filter rules to match this USB host class instance against a device class **/
+	const struct usbh_class_filter *filters;
+	/** State of the USB class instance */
+	enum usbh_class_state state;
+};
+/* @endcond */
+
+/**
+ * @brief Define USB host support class data
+ *
+ * Macro defines class (function) data, as well as corresponding node
+ * structures used internally by the stack.
+ *
+ * @param[in] class_name Class name
+ * @param[in] class_api  Pointer to struct usbh_class_api
+ * @param[in] class_priv Class private data
+ * @param[in] filt Array of @ref usbh_class_filter to match this class or NULL to match everything.
+ *                 When non-NULL, then it has to be terminated by an entry with @c flags set to 0.
+ */
+#define USBH_DEFINE_CLASS(class_name, class_api, class_priv, filt)		\
+	static struct usbh_class_data UTIL_CAT(class_data_, class_name) = {	\
+		.name = STRINGIFY(class_name),					\
+		.api = class_api,						\
+		.priv = class_priv,						\
+	};									\
+	static STRUCT_SECTION_ITERABLE(usbh_class_node, class_name) = {		\
+		.c_data = &UTIL_CAT(class_data_, class_name),			\
+		.filters = filt,						\
+	};
 
 /**
  * @brief Initialize the USB host support;

subsys/usb/CMakeLists.txt

@@ -5,3 +5,4 @@ add_subdirectory_ifdef(CONFIG_USB_DEVICE_STACK device)
 add_subdirectory_ifdef(CONFIG_USB_DEVICE_STACK_NEXT device_next)
 add_subdirectory_ifdef(CONFIG_USB_HOST_STACK host)
 add_subdirectory_ifdef(CONFIG_USBC_STACK usb_c)
+add_subdirectory(common)

subsys/usb/common/CMakeLists.txt

@@ -0,0 +1,4 @@
+# SPDX-FileCopyrightText: Copyright Nordic Semiconductor ASA
+# SPDX-License-Identifier: Apache-2.0
+
+zephyr_include_directories(include)

subsys/usb/device_next/class/usbd_uvc.c

@@ -23,7 +23,8 @@
 #include <zephyr/sys/util.h>
 #include <zephyr/usb/class/usbd_uvc.h>
 
-#include "usbd_uvc.h"
+#include "usb_uvc.h"
+
 #include "../../../drivers/video/video_ctrls.h"
 #include "../../../drivers/video/video_device.h"
 

subsys/usb/host/CMakeLists.txt

@@ -1,14 +1,17 @@
-# Copyright (c) 2022 Nordic Semiconductor ASA
+# SPDX-FileCopyrightText: Copyright Nordic Semiconductor ASA
 # SPDX-License-Identifier: Apache-2.0
 
 zephyr_library()
 zephyr_library_include_directories(${CMAKE_CURRENT_SOURCE_DIR})
 
 zephyr_library_sources(
   usbh_ch9.c
+  usbh_class.c
   usbh_core.c
   usbh_api.c
   usbh_device.c
+  usbh_desc.c
+  usbh_class.c
 )
 
 zephyr_library_sources_ifdef(