Clean up bandwidth usage info when deleting a pipe

USBHost_t36.h

 	void     (*callback_function)(const Transfer_t *);
 	uint16_t periodic_interval;
 	uint16_t periodic_offset;
+	uint16_t bandwidth_interval;
+	uint16_t bandwidth_offset;
+	uint16_t bandwidth_shift;
+	uint8_t  bandwidth_stime;
+	uint8_t  bandwidth_ctime;
 	uint32_t unused1;
 	uint32_t unused2;
 	uint32_t unused3;
 	uint32_t unused4;
 	uint32_t unused5;
-	uint32_t unused6;
-	uint32_t unused7;
 };
 
 // Transfer_t represents a single transaction on the USB bus.
 public:
 	static void begin();
 	static void Task();
+	static void countFree(uint32_t &devices, uint32_t &pipes, uint32_t &trans, uint32_t &strs);
 protected:
 	static Pipe_t * new_Pipe(Device_t *dev, uint32_t type, uint32_t endpoint,
 		uint32_t direction, uint32_t maxlen, uint32_t interval=0);

ehci.cpp

 		// a 125 us micro frame can fit 7500 bytes, or 234 of our 32-byte units
 		// fail if the best found needs more than 80% (234 * 0.8) in any uframe
 		if (best_bandwidth > 187) return false;
+		// save essential bandwidth specs, for cleanup in delete_Pipe
+		pipe->bandwidth_interval = interval;
+		pipe->bandwidth_offset = best_offset;
+		pipe->bandwidth_stime = stime;
 		for (uint32_t i=best_offset; i < PERIODIC_LIST_SIZE*8; i += interval) {
 			uframe_bandwidth[i] += stime;
 		}
 		// a 125 us micro frame can fit 7500 bytes, or 234 of our 32-byte units
 		// fail if the best found needs more than 80% (234 * 0.8) in any uframe
 		if (best_bandwidth > 187) return false;
+		// save essential bandwidth specs, for cleanup in delete_Pipe
+		pipe->bandwidth_interval = interval;
+		pipe->bandwidth_offset = best_offset;
+		pipe->bandwidth_shift = best_shift;
+		pipe->bandwidth_stime = stime;
+		pipe->bandwidth_ctime = ctime;
 		for (uint32_t i=best_offset; i < PERIODIC_LIST_SIZE; i += interval) {
 			uint32_t n = (i << 3) + best_shift;
 			uframe_bandwidth[n+0] += stime;
 				prev = node;
 			}
 		}
-		// TODO: subtract bandwidth from uframe_bandwidth array
+		// subtract bandwidth from uframe_bandwidth array
+		if (pipe->device->speed == 2) {
+			uint32_t interval = pipe->bandwidth_interval;
+			uint32_t offset = pipe->bandwidth_offset;
+			uint32_t stime = pipe->bandwidth_stime;
+			for (uint32_t i=offset; i < PERIODIC_LIST_SIZE*8; i += interval) {
+				uframe_bandwidth[i] -= stime;
+			}
+		} else {
+			uint32_t interval = pipe->bandwidth_interval;
+			uint32_t offset = pipe->bandwidth_offset;
+			uint32_t shift = pipe->bandwidth_shift;
+			uint32_t stime = pipe->bandwidth_stime;
+			uint32_t ctime = pipe->bandwidth_ctime;
+			for (uint32_t i=offset; i < PERIODIC_LIST_SIZE; i += interval) {
+				uint32_t n = (i << 3) + shift;
+				uframe_bandwidth[n+0] -= stime;
+				uframe_bandwidth[n+2] -= ctime;
+				uframe_bandwidth[n+3] -= ctime;
+				uframe_bandwidth[n+4] -= ctime;
+			}
+		}
 
 		// find & free all the transfers which completed
 		println("  Free transfers");

memory.cpp

 	}
 }
 
-
+// for debugging, hopefully never needed...
+void USBHost::countFree(uint32_t &devices, uint32_t &pipes, uint32_t &transfers, uint32_t &strs)
+{
+	uint32_t ndev=0, npipe=0, ntransfer=0, nstr=0;
+	__disable_irq();
+	Device_t *dev = free_Device_list;
+	while (dev) {
+		ndev++;
+		dev = *(Device_t **)dev;
+	}
+	Pipe_t *pipe = free_Pipe_list;
+	while (pipe) {
+		npipe++;
+		pipe = *(Pipe_t **)pipe;
+	}
+	Transfer_t *transfer = free_Transfer_list;
+	while (transfer) {
+		ntransfer++;
+		transfer = *(Transfer_t **)transfer;
+	}
+	strbuf_t *str = free_strbuf_list;
+	while (str) {
+		nstr++;
+		str = *(strbuf_t **)str;
+	}
+	__enable_irq();
+	devices = ndev;
+	pipes = npipe;
+	transfers = ntransfer;
+	strs = nstr;
+}