- some fixes

usb.c

@@ -20,15 +20,15 @@
 // ---------------
 
 static uint8_t tx_assembly_buf[USB_RX_BUF_SIZE] DWORD_ALIGN; ///< Buffer for assembling packets
-static Usb_SetupTransferState stups; ///< Setup transfer state.
+static Usb_SetupTransferState stups;                         ///< Setup transfer state.
-static UsbDrv_DrvIntf *drv; ///< Mutable pointer to the driver interface
+static UsbDrv_DrvIntf *drv;                                  ///< Mutable pointer to the driver interface
 
 // ----------------
 
 /**
  * @fn void usb_event_callback(USB_CallbackEvent *cbevt)
  * Prototype for the USB event callback.
- * 
+ *
  * @param cbevt pointer to the event data
  */
 __attribute__((weak)) void usb_event_callback(Usb_CallbackEvent *cbevt) {
@@ -64,9 +64,25 @@ void usbcore_reset() {
     memset(&stups, 0, sizeof(Usb_SetupTransferState));
 }
 
+/**
+ * Response follow-up if the ful response could not fit in a single packet.
+ *
+ * @param ep endpoint number
+ */
+static void usbcore_response_follow_up(uint8_t ep) {
+    uint32_t armSize = drv->arm_IN(0, stups.fup_data, stups.fup_sz);
+    stups.fup_sz -= armSize;   // calculate remaining follow-up size
+    stups.fup_data += armSize; // advance follow-up data pointer
+
+    if (stups.fup_sz > 0) {      // we need further follow-ups
+    } else {                     // transfer done, remove callback
+        drv->reg_IN_cb(0, NULL); // remove IN callback
+    }
+}
+
 /**
  * Process SETUP packets.
- * 
+ *
  * @param data pointer to the SETUP packet
  * @param size size of the packet
  * @param stage stage of the SETUP transaction
@@ -158,7 +174,12 @@ void usbcore_process_setup_pckt(const uint8_t *data, uint16_t size, uint8_t stag
         }
 
         // arm data transmission
-        drv->arm_IN(0, data, sz);
+        uint32_t armSize = drv->arm_IN(0, data, sz);
+        if (armSize < sz) {                                // if could not arm the full response at once, then hook up a callback
+            stups.fup_sz = sz - armSize;                   // follow-up size
+            stups.fup_data = data + armSize;               // generate follow-up data pointer
+            drv->reg_IN_cb(0, usbcore_response_follow_up); // register follow-up callback
+        }
         break;
     }
 
@@ -205,14 +226,14 @@ void usbcore_process_setup_pckt(const uint8_t *data, uint16_t size, uint8_t stag
 
 /**
  * Process the non-SETUP packets.
- * 
+ *
  * @param cbcpd pointer to callback compound
  */
 void usbcore_process_nonsetup_event(UsbDrv_CallbackCompound *cbcpd) {
     Usb_CallbackEvent cbevt = {0}; // allocate and clear structure...
     cbevt.ep = cbcpd->ep;          // later only fill nonzero fields
 
-    bool discard_event = false; // only discard if event does not fit any category above
+    bool discard_event = false; // only discard if event does not fit any category below
     switch (cbcpd->code) {
     case USB_CBC_OUT: {
         cbevt.type = USB_CBEVT_OUT;

usb.h

@@ -15,6 +15,8 @@ typedef struct {
     USB_SetupRequest setup_req; ///< Setup request
     uint8_t next_stage;         ///< Next expected stage
     bool out_complete;          ///< Signals if transfer's OUT direction is complete, no later data reception is expected
+    uint16_t fup_sz;         ///< Some SETUP response IN data follows
+    const uint8_t * fup_data;         ///< Pointer on follow-up data
 } Usb_SetupTransferState;
 
 // --------------