Add hub characteristics to BOS descriptor

Adds the following hub charcteristics to a new platform capability
in the BOS Descriptor:

 * Software version
 * Protocol version
 * Hub feature flags
 * Max program size

We reuse {A5C44A4C-53D4-4389-9821-AE95051908A1}, the value of the
DeviceInterfaceGUID, as the platform capability UUID.

lib/pbio/drv/usb/stm32_usbd/usbd_desc.c

@@ -47,6 +47,13 @@
 #include "usbd_conf.h"
 #include "usbd_pybricks.h"
 
+#include "pbio/protocol.h"
+#include "pbio/version.h"
+#include "pbsys/app.h"
+#include "pbsys/program_load.h"
+#include "pbdrvconfig.h"
+#include "sys/config.h"
+
 /* Private typedef -----------------------------------------------------------*/
 /* Private define ------------------------------------------------------------*/
 #define USBD_VID                      0x0483
@@ -62,7 +69,7 @@
 #define         DEVICE_ID3          (0x1FFF7A18)
 
 #define  USB_SIZ_STRING_SERIAL       0x1A
-#define  USB_SIZ_BOS_DESC            33
+#define  USB_SIZ_BOS_DESC            (5 + 28 + 34)
 
 /* USB Standard Device Descriptor */
 __ALIGN_BEGIN uint8_t USBD_DeviceDesc[USB_LEN_DEV_DESC] __ALIGN_END = {
@@ -98,12 +105,14 @@ __ALIGN_BEGIN uint8_t USBD_DeviceDesc[USB_LEN_DEV_DESC] __ALIGN_END = {
 #endif /* defined ( __ICCARM__ ) */
 __ALIGN_BEGIN uint8_t USBD_BOSDesc[USB_SIZ_BOS_DESC] __ALIGN_END =
 {
+  /* --- BOS Decriptor --- */
   5,                          /* bLength */
   USB_DESC_TYPE_BOS,          /* bDescriptorType = BOS */
   LOBYTE(USB_SIZ_BOS_DESC),   /* wTotalLength */
   HIBYTE(USB_SIZ_BOS_DESC),   /* wTotalLength */
-  0x01,                       /* bNumDeviceCaps = 1 */
+  0x02,                       /* bNumDeviceCaps = 2 */
 
+  /* --- Platform Capability --- */
   28,                         /* bLength */
   USB_DEVICE_CAPABITY_TYPE,   /* bDescriptorType = Device Capability */
   0x05,                       /* bDevCapabilityType = Platform */
@@ -124,7 +133,44 @@ __ALIGN_BEGIN uint8_t USBD_BOSDesc[USB_SIZ_BOS_DESC] __ALIGN_END =
   LOBYTE(USB_SIZ_MS_OS_DSCRPTR_SET),  /* wMSOSDescriptorSetTotalLength */
   HIBYTE(USB_SIZ_MS_OS_DSCRPTR_SET),  /* wMSOSDescriptorSetTotalLength */
   USB_MS_VENDOR_CODE,                 /* bMS_VendorCode */
-  0x00                                /* bAltEnumCode = Does not support alternate enumeration */
+  0x00,                               /* bAltEnumCode = Does not support alternate enumeration */
+
+  /* --- Platform Capability --- */
+  34,                                 /* bLength */
+  USB_DEVICE_CAPABITY_TYPE,           /* bDescriptorType = Device Capability */
+  0x05,                               /* bDevCapabilityType = Platform */
+  0x00,                               /* bReserved */
+
+  /*
+   * PlatformCapabilityUUID
+   * Pybricks
+   * A5C44A4C-53D4-4389-9821-AE95051908A1
+   */
+  0x4C, 0x4A, 0xC4, 0xA5,
+  0xD4, 0x53,
+  0x89, 0x43,
+  0x98, 0x21,
+  0xAE, 0x95, 0x05, 0x19, 0x08, 0xA1,
+
+  PBIO_VERSION_MAJOR,                 /* Firmware version (major) */
+  PBIO_VERSION_MINOR,                 /* Firmware version (minor) */
+  PBIO_VERSION_MICRO,                 /* Firmware version (micro) */
+
+  PBIO_PROTOCOL_VERSION_MAJOR,        /* Protocol version (major) */
+  PBIO_PROTOCOL_VERSION_MINOR,        /* Protocol version (minor) */
+  PBIO_PROTOCOL_VERSION_PATCH,        /* Protocol version (patch) */
+
+  /* Hub feature flags */
+  (PBSYS_APP_HUB_FEATURE_FLAGS)       & 0xFF,
+  (PBSYS_APP_HUB_FEATURE_FLAGS >> 8)  & 0xFF,
+  (PBSYS_APP_HUB_FEATURE_FLAGS >> 16) & 0xFF,
+  (PBSYS_APP_HUB_FEATURE_FLAGS >> 24) & 0xFF,
+
+  /* Program size */
+  (PBSYS_PROGRAM_LOAD_MAX_PROGRAM_SIZE)       & 0xFF,
+  (PBSYS_PROGRAM_LOAD_MAX_PROGRAM_SIZE >> 8)  & 0xFF,
+  (PBSYS_PROGRAM_LOAD_MAX_PROGRAM_SIZE >> 16) & 0xFF,
+  (PBSYS_PROGRAM_LOAD_MAX_PROGRAM_SIZE >> 24) & 0xFF,
 };
 #endif /* (USBD_LPM_ENABLED == 1) || (USBD_CLASS_BOS_ENABLED == 1) */