samples: usb: add a sample USB 2.0 Extension Descriptor

Add a sample USB 2.0 Extension Descriptor.

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

Author: jfischer-no

samples/subsys/usb/common/Kconfig.sample_usbd

@@ -45,4 +45,9 @@ config SAMPLE_USBD_MAX_POWER
 	help
 	  bMaxPower value in the sample configuration in 2 mA units.
 
+config SAMPLE_USBD_20_EXTENSION_DESC
+	bool "Use default USB 2.0 Extension Descriptor"
+	help
+	  Set bcdUSB value to 0201 and use default USB 2.0 Extension Descriptor.
+
 endmenu

samples/subsys/usb/common/sample_usbd_init.c

@@ -8,6 +8,7 @@
 
 #include <zephyr/device.h>
 #include <zephyr/usb/usbd.h>
+#include <zephyr/usb/bos.h>
 #include <zephyr/sys/iterable_sections.h>
 
 #include <zephyr/logging/log.h>
@@ -37,6 +38,19 @@ USBD_CONFIGURATION_DEFINE(sample_hs_config,
 			  attributes,
 			  CONFIG_SAMPLE_USBD_MAX_POWER);
 
+/*
+ * This does not yet provide valuable information, but rather serves as an
+ * example, and will be improved in the future.
+ */
+static const struct usb_bos_capability_lpm bos_cap_lpm = {
+	.bLength = sizeof(struct usb_bos_capability_lpm),
+	.bDescriptorType = USB_DESC_DEVICE_CAPABILITY,
+	.bDevCapabilityType = USB_BOS_CAPABILITY_EXTENSION,
+	.bmAttributes = 0UL,
+};
+
+USBD_DESC_BOS_DEFINE(sample_usbext, sizeof(bos_cap_lpm), &bos_cap_lpm);
+
 static int register_fs_classes(struct usbd_contex *uds_ctx)
 {
 	int err = 0;
@@ -169,6 +183,17 @@ struct usbd_contex *sample_usbd_init_device(usbd_msg_cb_t msg_cb)
 		}
 	}
 
+	if (IS_ENABLED(CONFIG_SAMPLE_USBD_20_EXTENSION_DESC)) {
+		(void)usbd_device_set_bcd(&sample_usbd, USBD_SPEED_FS, 0x0201);
+		(void)usbd_device_set_bcd(&sample_usbd, USBD_SPEED_HS, 0x0201);
+
+		err = usbd_add_descriptor(&sample_usbd, &sample_usbext);
+		if (err) {
+			LOG_ERR("Failed to add USB 2.0 Extension Descriptor");
+			return NULL;
+		}
+	}
+
 	err = usbd_init(&sample_usbd);
 	if (err) {
 		LOG_ERR("Failed to initialize device support");