I2C EEPROM support for OTA using dual Optiboot #802 (#834)

* Added support for I2C EEPROM OTA

* EEPROM OTA now uses extEEPROM as driver

* Compiler warning fix

* Style check fixes

* Fix doxygen warnings of I2CEeprom

* Use bool instead of boolean in I2CEeprom shim

* Fix re-merged style problem

MyConfig.h

@@ -261,6 +261,19 @@
 // requires the MYSBootloader and disabled MY_OTA_FIRMWARE_FEATURE
 //#define MY_OTA_FIRMWARE_FEATURE
 
+// Define or uncomment MY_OTA_USE_I2C_EEPROM below if you want I2C EEPROM instead
+// of a SPI flash. Used EEPROM needs to be large enough, an 24(L)C256 will do as minimum.
+// HW I2C assumed. This will exclude the SPI flash code.
+// Note that you also need an updated DualOptiboot supporting I2C EEPROM!
+//#define MY_OTA_USE_I2C_EEPROM
+
+#ifdef MY_OTA_USE_I2C_EEPROM
+// I2C address of EEPROM. Wire will shift this left, i.e. 0x50->0xA0
+#ifndef MY_OTA_I2C_ADDR
+#define MY_OTA_I2C_ADDR		0x50
+#endif
+#endif
+
 /**
  * @def MY_OTA_FLASH_SS
  * @brief Slave select pin for external flash.

MySensors.h

@@ -172,7 +172,11 @@ MY_DEFAULT_RX_LED_PIN in your sketch instead to enable LEDs
 
 // FLASH
 #if defined(MY_OTA_FIRMWARE_FEATURE)
+#if defined(MY_OTA_USE_I2C_EEPROM)
+#include "drivers/I2CEeprom/I2CEeprom.cpp"
+#else
 #include "drivers/SPIFlash/SPIFlash.cpp"
+#endif
 #include "core/MyOTAFirmwareUpdate.cpp"
 #endif
 

core/MyOTAFirmwareUpdate.cpp

@@ -24,7 +24,11 @@ extern MyMessage _msg;
 extern MyMessage _msgTmp;
 
 // local variables
+#ifdef MY_OTA_USE_I2C_EEPROM
+I2CEeprom _flash(MY_OTA_I2C_ADDR);
+#else
 SPIFlash _flash(MY_OTA_FLASH_SS, MY_OTA_FLASH_JDECID);
+#endif
 nodeFirmwareConfig_t _nodeFirmwareConfig;
 bool _firmwareUpdateOngoing;
 uint32_t _firmwareLastRequest;
@@ -110,6 +114,21 @@ bool firmwareOTAUpdateProcess(void)
 			                   firmwareResponse->data, FIRMWARE_BLOCK_SIZE);
 			// wait until flash written
 			while (_flash.busy()) {}
+#ifdef OTA_EXTRA_FLASH_DEBUG
+			{
+				char prbuf[8];
+				uint32_t addr = ((_firmwareBlock - 1) * FIRMWARE_BLOCK_SIZE) + FIRMWARE_START_OFFSET;
+				OTA_DEBUG(PSTR("OTA:FWP:FL DUMP "));
+				sprintf_P(prbuf,PSTR("%04X:"), (uint16_t)addr);
+				MY_SERIALDEVICE.print(prbuf);
+				for(uint8_t i=0; i<FIRMWARE_BLOCK_SIZE; i++) {
+					uint8_t data = _flash.readByte(addr + i);
+					sprintf_P(prbuf,PSTR("%02X"), (unsigned int)data);
+					MY_SERIALDEVICE.print(prbuf);
+				}
+				OTA_DEBUG(PSTR("\n"));
+			}
+#endif
 			_firmwareBlock--;
 			if (!_firmwareBlock) {
 				// We're done! Do a checksum and reboot.

core/MyOTAFirmwareUpdate.h

@@ -70,6 +70,7 @@
 
 #if defined(MY_DEBUG_VERBOSE_OTA_UPDATE)
 #define OTA_DEBUG(x,...) hwDebugPrint(x, ##__VA_ARGS__)	//!< debug
+//#define OTA_EXTRA_FLASH_DEBUG	//!< Dumps flash after each FW block
 #else
 #define OTA_DEBUG(x,...)	//!< debug NULL
 #endif

drivers/I2CEeprom/I2CEeprom.cpp

@@ -0,0 +1,81 @@
+// Copyright (C) 2016 Krister W. <kisse66@hobbylabs.org>
+//
+// Original SPI flash driver this is based on:
+// Copyright (c) 2013-2015 by Felix Rusu, LowPowerLab.com
+// **********************************************************************************
+// License
+// **********************************************************************************
+// This program is free software; you can redistribute it
+// and/or modify it under the terms of the GNU General
+// Public License as published by the Free Software
+// Foundation; either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will
+// be useful, but WITHOUT ANY WARRANTY; without even the
+// implied warranty of MERCHANTABILITY or FITNESS FOR A
+// PARTICULAR PURPOSE. See the GNU General Public
+// License for more details.
+//
+// You should have received a copy of the GNU General
+// Public License along with this program.
+// If not, see <http://www.gnu.org/licenses/>.
+//
+// Licence can be viewed at
+// http://www.gnu.org/licenses/gpl-3.0.txt
+//
+// Please maintain this license information along with authorship
+// and copyright notices in any redistribution of this code
+
+#include <Wire.h>
+#include "I2CEeprom.h"
+
+I2CEeprom::I2CEeprom(uint8_t addr) : extEEPROM(I2CEEPROM_CHIP_SIZE, 1, I2CEEPROM_PAGE_SIZE)
+{
+	m_addr = addr;    // we only need this for busy()
+}
+
+/// setup
+bool I2CEeprom::initialize()
+{
+	return extEEPROM::begin(I2CEEPROM_TWI_CLK) ? false : true;
+}
+
+/// read 1 byte
+uint8_t I2CEeprom::readByte(uint32_t addr)
+{
+	uint8_t val;
+	readBytes(addr, &val, 1);
+	return val;
+}
+
+/// read multiple bytes
+void I2CEeprom::readBytes(uint32_t addr, void* buf, uint16_t len)
+{
+	extEEPROM::read((unsigned long)addr, (byte *)buf, (unsigned int) len);
+}
+
+/// check if the chip is busy
+bool I2CEeprom::busy()
+{
+	Wire.beginTransmission(m_addr);
+	Wire.write(0);
+	Wire.write(0);
+	if (Wire.endTransmission() == 0) {
+		return false;
+	} else {
+		return true;    // busy
+	}
+}
+
+/// Write 1 byte
+void I2CEeprom::writeByte(uint32_t addr, uint8_t byt)
+{
+	writeBytes(addr, &byt, 1);
+}
+
+/// write multiple bytes
+void I2CEeprom::writeBytes(uint32_t addr, const void* buf, uint16_t len)
+{
+	extEEPROM::write((unsigned long) addr, (byte *)buf, (unsigned int) len);
+}

drivers/I2CEeprom/I2CEeprom.h

@@ -0,0 +1,116 @@
+// Copyright (C) 2016 Krister W. <kisse66@hobbylabs.org>
+//
+// Original SPI flash driver this is based on:
+// Copyright (c) 2013-2015 by Felix Rusu, LowPowerLab.com
+//
+// I2C EEPROM library for MySensors OTA. Based on SPI Flash memory library for
+// arduino/moteino.
+// This driver is made to look like the SPI flash driver so changes needed to
+// MySensors OTA code is minimized.
+// This works with 32 or 64kB I2C EEPROM like an 24(L)C256. AVR HW I2C is assumed
+// and error handling is quite minimal. Uses extEEPROM as the underlying driver.
+// DEPENDS ON: Arduino Wire library, extEEPROM
+// **********************************************************************************
+// License
+// **********************************************************************************
+// This program is free software; you can redistribute it
+// and/or modify it under the terms of the GNU General
+// Public License as published by the Free Software
+// Foundation; either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will
+// be useful, but WITHOUT ANY WARRANTY; without even the
+// implied warranty of MERCHANTABILITY or FITNESS FOR A
+// PARTICULAR PURPOSE. See the GNU General Public
+// License for more details.
+//
+// You should have received a copy of the GNU General
+// Public License along with this program.
+// If not, see <http://www.gnu.org/licenses/>.
+//
+// Licence can be viewed at
+// http://www.gnu.org/licenses/gpl-3.0.txt
+//
+// Please maintain this license information along with authorship
+// and copyright notices in any redistribution of this code
+
+///
+/// @file I2CEeprom.h
+///
+/// @brief I2CEeprom provides access to a I2C EEPROM IC for OTA update or storing data
+///
+/// This is a wrapper over extEEPROM to make it look like a flash chip.
+///
+#ifndef _I2CEeprom_H_
+#define _I2CEeprom_H_
+
+#include <Arduino.h>
+#include <extEEPROM.h>
+
+/// I2C speed
+// 400kHz clock as default. Use extEEPROM type
+#ifndef I2CEEPROM_TWI_CLK
+#define I2CEEPROM_TWI_CLK twiClock400kHz
+#endif
+
+/// EEPROM page size
+//Typically 64 (see data sheet for your EEPROM)
+// Some 512kbit chips use 128 byte pages (e.g. Atmel AT24C512)
+#ifndef I2CEEPROM_PAGE_SIZE
+#define I2CEEPROM_PAGE_SIZE 64
+#endif
+
+/// EEPROM size
+// 24C256 is 32kB, minimum that fits code for ATmega328
+// Use extEEPROM type
+#ifndef I2CEEPROM_CHIP_SIZE
+#define I2CEEPROM_CHIP_SIZE kbits_256
+#endif
+
+/** I2CEeprom class */
+class I2CEeprom : extEEPROM
+{
+public:
+
+	explicit I2CEeprom(uint8_t addr); //!< Constructor
+	bool initialize(); //!< setup
+	uint8_t readByte(uint32_t addr); //!< read 1 byte from flash memory
+	void readBytes(uint32_t addr, void* buf, uint16_t len); //!< read multiple bytes
+	void writeByte(uint32_t addr, uint8_t byt); //!< Write 1 byte to flash memory
+	void writeBytes(uint32_t addr, const void* buf,
+	                uint16_t len); //!< write multiple bytes to flash memory (up to 64K), if define SPIFLASH_SST25TYPE is set AAI Word Programming will be used
+	bool busy(); //!< check if the chip is busy erasing/writing
+
+	// the rest not needed for EEPROMs, but kept so SPI flash code compiles as is (functions are NOP)
+
+	/// dummy function for SPI flash compatibility
+	uint16_t readDeviceId()
+	{
+		return 0xDEAD;
+	};
+	/// dummy function for SPI flash compatibility
+	void chipErase() {};
+	/// dummy function for SPI flash compatibility
+	void blockErase4K(uint32_t address)
+	{
+		(void)address;
+	};
+	/// dummy function for SPI flash compatibility
+	void blockErase32K(uint32_t address)
+	{
+		(void)address;
+	};
+	/// dummy function for SPI flash compatibility
+	void sleep() {};
+	/// dummy function for SPI flash compatibility
+	void wakeup() {};
+	/// dummy function for SPI flash compatibility
+	void end() {};
+
+protected:
+
+	uint8_t m_addr; ///< I2C address for busy()
+};
+
+#endif