USBSerial fix add USBSerialEmu

I was workign on some other USBHost extensions and found I needed debug information that was
being generated by a Teensy plugged into the USB host port that was output using Serial Emulation
to be available.  Likewise I wanted the ability to feed data back to that other Teensy.

So I decided to create USBHost_t36 implemention to handle the USB types that include Serial Emulation
USBSerialEmu class.

The USBSerialEmu code was based on the USBSerial code as well as RAWHID.  I found that there was a bug
in the Receiving of data that was sent by the remote SEREMU output, I would miss the first character
Fixed.

USBSerial fixed same bug in reading first character

SerEMU.cpp

+/* USB EHCI Host for Teensy 3.6
+ * Copyright 2017 Paul Stoffregen (paul@pjrc.com)
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+ * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+ * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+ * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+ * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#include <Arduino.h>
+#include "USBHost_t36.h"  // Read this header first for key info
+
+//#define  SEREMU_PRINT_DEBUG
+
+
+void USBSerialEmu::init()
+{
+	USBHost::contribute_Transfers(mytransfers, sizeof(mytransfers)/sizeof(Transfer_t));
+	USBHIDParser::driver_ready_for_hid_collection(this);	
+}
+
+hidclaim_t USBSerialEmu::claim_collection(USBHIDParser *driver, Device_t *dev, uint32_t topusage)
+{
+	// only claim SerEMU devices currently: 16c0:0486
+#ifdef SEREMU_PRINT_DEBUG
+	USBHDBGSerial.printf("SerEMU Claim: %x:%x usage: %x\n", dev->idVendor, dev->idProduct, topusage);
+#endif
+
+	if (dev->idVendor != 0x16c0) return CLAIM_NO;  //  NOT PJRC
+	if (mydevice != NULL && dev != mydevice) return CLAIM_NO;
+	if (usage_) return CLAIM_NO;			// Only claim one
+
+	// make sure it is the SEREMU usage
+	if (topusage != 0xffc90004) return CLAIM_NO; 			// Not the SEREMU
+
+	mydevice = dev;
+	collections_claimed++;
+	usage_ = topusage;
+	driver_ = driver;	// remember the driver. 
+	rx_head_ = 0;// receive head
+	rx_tail_ = 0;// receive tail
+	tx_head_ = 0;
+	rx_pipe_size_ = driver->inSize();
+	tx_pipe_size_ = driver->outSize();
+	tx_out_data_pending_ = 0;
+
+
+	//if (setup.word1 == 0x03000921 && setup.word2 == ((4<<16)|SEREMU_INTERFACE)) {
+	tx_buffer_[0] = 0;
+	tx_buffer_[1] = 0;
+	tx_buffer_[2] = 0;
+	tx_buffer_[3] = 0;
+	driver_->sendControlPacket( 0x21, 0x9, 0x300, driver_->interfaceNumber(), 4, tx_buffer_);
+
+	return CLAIM_INTERFACE;  // We wa
+}
+
+void USBSerialEmu::disconnect_collection(Device_t *dev)
+{
+	if (--collections_claimed == 0) {
+		mydevice = NULL;
+		usage_ = 0;
+	}
+}
+
+bool USBSerialEmu::hid_process_in_data(const Transfer_t *transfer) 
+{
+	uint16_t len = transfer->length;
+	const uint8_t *buffer = (const uint8_t *)transfer->buffer;
+#ifdef SEREMU_PRINT_DEBUG
+	USBHDBGSerial.printf("USBSerialEmu::hid_process_in_data: %x %d: %x %x %x\n", usage_, len, buffer[0], buffer[1], buffer[2]);
+#endif
+	const uint8_t *buffer_end = buffer + len -1;
+	while ((buffer_end > buffer) && (*buffer_end == 0))buffer_end--;
+	// lets trim off the trailing null characters.
+
+	// Now lets move the bytes onto our queue. 
+	uint16_t tail = rx_tail_;
+	while (buffer <= buffer_end) {
+		uint16_t new_head = rx_head_ + 1;
+		if (new_head == RX_BUFFER_SIZE) new_head = 0;
+		if (new_head == tail) break; // we don't have room so bail out. 
+		rx_buffer_[rx_head_] = *buffer++;
+		rx_head_ = new_head;	// point off to the new next head.
+	}
+	return true;
+}
+
+bool USBSerialEmu::hid_process_out_data(const Transfer_t *transfer) 
+{
+#ifdef SEREMU_PRINT_DEBUG
+	USBHDBGSerial.printf("USBSerialEmu::hid_process_out_data: %x\n", usage_);
+#endif
+	if (tx_out_data_pending_) {
+		tx_out_data_pending_--;
+
+	}
+	return true;
+}
+
+bool USBSerialEmu::sendPacket() 
+{
+	USBHDBGSerial.printf("SEMU: SendPacket\n");
+
+	if (!driver_) return false;
+	if (!driver_->sendPacket(tx_buffer_)) return false;
+	tx_out_data_pending_++;
+	tx_head_ = 0;
+	return true;
+}
+
+
+int USBSerialEmu::available(void)
+{
+	if (!driver_) return 0;
+	uint32_t head = rx_head_;
+	uint32_t tail = rx_tail_;
+	if (head >= tail) return head - tail;
+	return RX_BUFFER_SIZE + head - tail;
+}
+
+int USBSerialEmu::peek(void)
+{
+	if (!driver_) return -1;
+	if (rx_head_ == rx_tail_) return -1;
+	return rx_buffer_[rx_tail_];
+}
+
+int USBSerialEmu::read(void)
+{
+	if (!driver_) return -1;
+	if (rx_head_ == rx_tail_) return -1;
+	int c = rx_buffer_[rx_tail_];
+	if (++rx_tail_ >= RX_BUFFER_SIZE) rx_tail_ = 0;
+
+	return c;
+}
+
+int USBSerialEmu::availableForWrite()
+{
+	if (!driver_) return 0;
+	return tx_pipe_size_ - tx_head_ + (2-tx_out_data_pending_)*tx_pipe_size_;
+}
+
+size_t USBSerialEmu::write(uint8_t c)
+{
+	// Single buffer, as our HID device has double buffers. 
+	if (c >= ' ') USBHDBGSerial.printf("SEMU: %c\n", c);
+	else USBHDBGSerial.printf("SEMU: 0x%x\n", c);
+
+
+	if (!driver_) return 0;
+
+	if (tx_head_ == tx_pipe_size_) {
+		while (!sendPacket()) yield();	// wait until the device above queues this packet 
+	}
+	tx_buffer_[tx_head_++] = c;
+
+	// if this character filled it. then try to queue it again
+	if (tx_head_ == tx_pipe_size_) sendPacket();
+	driver_->stopTimer();
+	driver_->startTimer(write_timeout_);
+	return 1;
+}
+
+void USBSerialEmu::flush(void) 
+{
+	if (!driver_) return;
+
+	USBHDBGSerial.printf("SEMU: flush\n");
+	driver_->stopTimer();  		// Stop longer timer.
+	driver_->startTimer(100);		// Start a mimimal timeout
+	if (tx_head_) sendPacket();
+
+	// And wait for HID to say they were all sent.
+	elapsedMillis em = 0;
+	while (tx_out_data_pending_ &&  (em < 10000)) yield(); // wait up to 10 seconds?
+}
+
+void USBSerialEmu::hid_timer_event(USBDriverTimer *whichTimer)
+{
+	USBHDBGSerial.printf("SEMU: Timer\n");
+	if (!driver_) return;
+	driver_->stopTimer();
+	if (tx_head_) {
+		memset(tx_buffer_ + tx_head_, 0, tx_pipe_size_ - tx_head_);	// clear the rest of bytes in buffer.
+		sendPacket();
+	}
+}
+
+void USBSerialEmu::hid_input_begin(uint32_t topusage, uint32_t type, int lgmin, int lgmax)
+{
+	// These should not be called as we are claiming the whole interface and not
+	// allowing the parse to happen
+#ifdef SEREMU_PRINT_DEBUG
+	USBHDBGSerial.printf("SerEMU::hid_input_begin %x %x %x %x\n", topusage, type, lgmin, lgmax);
+#endif
+	//hid_input_begin_ = true;
+}
+
+void USBSerialEmu::hid_input_data(uint32_t usage, int32_t value)
+{
+	// These should not be called as we are claiming the whole interface and not
+	// allowing the parse to happen
+#ifdef SEREMU_PRINT_DEBUG
+	USBHDBGSerial.printf("SerEMU: usage=%X, value=%d", usage, value);
+	if ((value >= ' ') && (value <='~')) USBHDBGSerial.printf("(%c)", value);
+	USBHDBGSerial.println();
+#endif
+}
+
+void USBSerialEmu::hid_input_end()
+{
+	// These should not be called as we are claiming the whole interface and not
+	// allowing the parse to happen
+#ifdef SEREMU_PRINT_DEBUG
+	USBHDBGSerial.println("SerEMU::hid_input_end");
+#endif
+//	if (hid_input_begin_) {
+//		hid_input_begin_ = false;
+//	}
+}

USBHost_t36.h

 // USBHost.
 class USBDriver;
 class USBDriverTimer;
+class USBHIDInput;
 
 /************************************************/
 /*  Added Defines                               */
 public:
 	USBDriverTimer() { }
 	USBDriverTimer(USBDriver *d) : driver(d) { }
+	USBDriverTimer(USBHIDInput *hd) : driver(nullptr), hidinput(hd) { }
+
 	void init(USBDriver *d) { driver = d; };
 	void start(uint32_t microseconds);
 	void stop();
 	uint32_t started_micros; // testing only
 private:
 	USBDriver      *driver;
+	USBHIDInput	   *hidinput;
 	uint32_t       usec;
 	USBDriverTimer *next;
 	USBDriverTimer *prev;
 	const uint8_t *serialNumber()
 		{  return  ((mydevice == nullptr) || (mydevice->strbuf == nullptr)) ? nullptr : &mydevice->strbuf->buffer[mydevice->strbuf->iStrings[strbuf_t::STR_ID_SERIAL]]; }
 
+
 private:
 	virtual hidclaim_t claim_collection(USBHIDParser *driver, Device_t *dev, uint32_t topusage);
 	virtual bool hid_process_in_data(const Transfer_t *transfer) {return false;}
 	virtual void hid_input_data(uint32_t usage, int32_t value);
 	virtual void hid_input_end();
 	virtual void disconnect_collection(Device_t *dev);
+	virtual void hid_timer_event(USBDriverTimer *whichTimer) { }
 	void add_to_list();
 	USBHIDInput *next = NULL;
 	friend class USBHIDParser;
 
 class USBHIDParser : public USBDriver {
 public:
-	USBHIDParser(USBHost &host) { init(); }
+	USBHIDParser(USBHost &host) : hidTimer(this) { init(); }
 	static void driver_ready_for_hid_collection(USBHIDInput *driver);
 	bool sendPacket(const uint8_t *buffer, int cb=-1);
 	void setTXBuffers(uint8_t *buffer1, uint8_t *buffer2, uint8_t cb);
 
 	bool sendControlPacket(uint32_t bmRequestType, uint32_t bRequest,
 			uint32_t wValue, uint32_t wIndex, uint32_t wLength, void *buf);
+
+	// Atempt for RAWhid and SEREMU to take over processing of data 
+	// 
+	uint16_t inSize(void) {return in_size;}
+	uint16_t outSize(void) {return out_size;}
+	void startTimer(uint32_t microseconds) {hidTimer.start(microseconds);}
+	void stopTimer() {hidTimer.stop();}
+	uint8_t interfaceNumber() { return bInterfaceNumber;}
 protected:
 	enum { TOPUSAGE_LIST_LEN = 4 };
 	enum { USAGE_LIST_LEN = 24 };
 	virtual void disconnect();
 	static void in_callback(const Transfer_t *transfer);
 	static void out_callback(const Transfer_t *transfer);
+	virtual void timer_event(USBDriverTimer *whichTimer);
 	void in_data(const Transfer_t *transfer);
 	void out_data(const Transfer_t *transfer);
 	bool check_if_using_report_id();
 	void parse(uint16_t type_and_report_id, const uint8_t *data, uint32_t len);
 	void init();
 
-	// Atempt for RAWhid to take over processing of data 
-	// 
-	uint16_t inSize(void) {return in_size;}
-	uint16_t outSize(void) {return out_size;}
 
 	uint8_t activeSendMask(void) {return txstate;} 
 
 	uint8_t *tx1 = nullptr;
 	uint8_t *tx2 = nullptr;
 	bool hid_driver_claimed_control_ = false;
+	USBDriverTimer hidTimer;
+	uint8_t bInterfaceNumber = 0;
 };
 
 //--------------------------------------------------------------------------
 
 //--------------------------------------------------------------------------
 
+class USBSerialEmu : public USBHIDInput, public Stream {
+public:
+	USBSerialEmu(USBHost &host) { init(); }
+	uint32_t usage(void) {return usage_;}
+
+	// Stream stuff. 
+	uint32_t writeTimeout() {return write_timeout_;}
+	void writeTimeOut(uint32_t write_timeout) {write_timeout_ = write_timeout;} // Will not impact current ones.
+	virtual int available(void);
+	virtual int peek(void);
+	virtual int read(void);
+	virtual int availableForWrite();
+	virtual size_t write(uint8_t c);
+	virtual void flush(void);
+
+	using Print::write;
+
+
+protected:
+	virtual hidclaim_t claim_collection(USBHIDParser *driver, Device_t *dev, uint32_t topusage);
+	virtual bool hid_process_in_data(const Transfer_t *transfer);
+	virtual bool hid_process_out_data(const Transfer_t *transfer);
+	virtual void hid_input_begin(uint32_t topusage, uint32_t type, int lgmin, int lgmax);
+	virtual void hid_input_data(uint32_t usage, int32_t value);
+	virtual void hid_input_end();
+	virtual void disconnect_collection(Device_t *dev);
+	virtual void hid_timer_event(USBDriverTimer *whichTimer);
+
+	bool sendPacket();
+
+private:
+	void init();
+	USBHIDParser *driver_;
+	enum { MAX_PACKET_SIZE = 64 };
+	bool (*receiveCB)(uint32_t usage, const uint8_t *data, uint32_t len) = nullptr;
+	uint8_t collections_claimed = 0;
+	uint32_t usage_ = 0;
+
+	// We have max of 512 byte packets coming in.  How about enough room for 3+3
+	enum { RX_BUFFER_SIZE=1024, TX_BUFFER_SIZE = 512 };
+	enum { DEFAULT_WRITE_TIMEOUT = 3500};
+
+	uint8_t rx_buffer_[RX_BUFFER_SIZE];
+	uint8_t tx_buffer_[TX_BUFFER_SIZE];
+
+	volatile uint8_t tx_out_data_pending_ = 0;
+
+	volatile uint16_t rx_head_;// receive head
+	volatile uint16_t rx_tail_;// receive tail
+	volatile uint16_t tx_head_;
+	uint16_t rx_pipe_size_;// size of receive circular buffer
+	uint16_t tx_pipe_size_;// size of transmit circular buffer
+	uint32_t write_timeout_ = DEFAULT_WRITE_TIMEOUT;
+
+
+	// See if we can contribute transfers
+	Transfer_t mytransfers[2] __attribute__ ((aligned(32)));
+
+};
+
+//--------------------------------------------------------------------------
+
 class BluetoothController: public USBDriver {
 public:
 	static const uint8_t MAX_CONNECTIONS = 4;
 	bool deviceAvailable = false;
 };
 
-
 #endif

hid.cpp

 	uint32_t numendpoint = descriptors[4];
 	if (numendpoint < 1 || numendpoint > 2) return false;
 	if (descriptors[5] != 3) return false; // bInterfaceClass, 3 = HID
+	println(" bInterfaceNumber =   ", descriptors[2]);
 	println(" bInterfaceClass =    ", descriptors[5]);
 	println(" bInterfaceSubClass = ", descriptors[6]);
 	println(" bInterfaceProtocol = ", descriptors[7]);
 		topusage_drivers[i] = NULL;
 	}
 	// request the HID report descriptor
+	bInterfaceNumber = descriptors[2];	// save away the interface number; 
 	mk_setup(setup, 0x81, 6, 0x2200, descriptors[2], descsize); // get report desc
 	queue_Control_Transfer(dev, &setup, descriptor, this);
 	return true;
 	}
 	USBHDBGSerial.printf("\n"); */
 
+	/*
 	print("HID: ");
 	print(use_report_id);
 	print(" - ");
 	print_hexbytes(transfer->buffer, transfer->length);
+	*/
 	const uint8_t *buf = (const uint8_t *)transfer->buffer;
 	uint32_t len = transfer->length;
 
 	}
 }
 
+void USBHIDParser::timer_event(USBDriverTimer *whichTimer)
+{
+	if (topusage_drivers[0]) {
+		topusage_drivers[0]->hid_timer_event(whichTimer);
+	}	
+}
+
+
 bool USBHIDParser::sendPacket(const uint8_t *buffer, int cb) {
 	if (!out_size || !out_pipe) return false;	
 	if (!tx1) {

keywords.txt

 MIDIDevice_BigBuffer	KEYWORD1
 USBSerial	KEYWORD1
 USBSerial_BigBuffer	KEYWORD1
+USBSerialEmu	KEYWORD1
 USBSerialBase	KEYWORD1
 AntPlus	KEYWORD1
 JoystickController	KEYWORD1

library.properties

 version=0.1
 author=Paul Stoffregen
 maintainer=Paul Stoffregen
-sentence=Connect USB devices to the USB Host of Teensy 3.6.
+sentence=Connect USB devices to the USB Host of Teensy 3.6 and Teensy 4.x
 paragraph=
 category=Communication
 url=https://github.com/PaulStoffregen/USBHost_t36
 architectures=*
-
+includes=USBHost_t36

rawhid.cpp

 	USBHDBGSerial.printf("Rawhid Claim: %x:%x usage: %x\n", dev->idVendor, dev->idProduct, topusage);
 #endif
 
-	if ((dev->idVendor != 0x16c0 || (dev->idProduct) != 0x486)) return CLAIM_NO;
+	if (dev->idVendor != 0x16c0) return CLAIM_NO;  //  NOT PJRC
 	if (mydevice != NULL && dev != mydevice) return CLAIM_NO;
 	if (usage_) return CLAIM_NO;			// Only claim one
-	if (fixed_usage_  && (fixed_usage_ != topusage)) return CLAIM_NO; 	// See if we want specific one and if so is it this one
+
+	if (fixed_usage_ ) {
+		if (fixed_usage_ != topusage) return CLAIM_NO; 		// See if we want specific one and if so is it this one
+	} else if (dev->idProduct != 0x486) return CLAIM_NO;	// otherwise mainly used for RAWHID Serial type.
+
 	mydevice = dev;
 	collections_claimed++;
 	usage_ = topusage;

serial.cpp

 int USBSerialBase::peek(void)
 {
 	if (!device) return -1;
-	uint32_t head = rxhead;
-	uint32_t tail = rxtail;
-	if (head == tail) return -1;
-	if (++tail >= rxsize) tail = 0;
-	return rxbuf[tail];
+	if (rxhead == rxtail) return -1;
+	return rxbuf[rxtail];
 }
 
 int USBSerialBase::read(void)
 {
 	if (!device) return -1;
-	uint32_t head = rxhead;
-	uint32_t tail = rxtail;
-	if (head == tail) return -1;
-	if (++tail >= rxsize) tail = 0;
-	int c = rxbuf[tail];
-	rxtail = tail;
+	if (rxhead == rxtail) return -1;
+	int c = rxbuf[rxtail];
+	if (++rxtail >= rxsize) rxtail = 0;
 	if ((rxstate & 0x03) != 0x03) {
 		NVIC_DISABLE_IRQ(IRQ_USBHS);
-		rx_queue_packets(head, tail);
+		rx_queue_packets(rxhead, rxtail);
 		NVIC_ENABLE_IRQ(IRQ_USBHS);
 	}
 	return c;