Revert "Wire library to the 1.5 format"

This reverts commit a318576.

Author: cmaglie

libraries/Wire/Wire.cpp

@@ -0,0 +1,384 @@
+/*
+ * TwoWire.h - TWI/I2C library for Arduino Due
+ * Copyright (c) 2011 Cristian Maglie <[email protected]>.
+ * All rights reserved.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+extern "C" {
+#include <string.h>
+}
+
+#include "Wire.h"
+
+static inline bool TWI_FailedAcknowledge(Twi *pTwi) {
+	return pTwi->TWI_SR & TWI_SR_NACK;
+}
+
+static inline bool TWI_WaitTransferComplete(Twi *_twi, uint32_t _timeout) {
+	while (!TWI_TransferComplete(_twi)) {
+		if (TWI_FailedAcknowledge(_twi))
+			return false;
+		if (--_timeout == 0)
+			return false;
+	}
+	return true;
+}
+
+static inline bool TWI_WaitByteSent(Twi *_twi, uint32_t _timeout) {
+	while (!TWI_ByteSent(_twi)) {
+		if (TWI_FailedAcknowledge(_twi))
+			return false;
+		if (--_timeout == 0)
+			return false;
+	}
+	return true;
+}
+
+static inline bool TWI_WaitByteReceived(Twi *_twi, uint32_t _timeout) {
+	while (!TWI_ByteReceived(_twi)) {
+		if (TWI_FailedAcknowledge(_twi))
+			return false;
+		if (--_timeout == 0)
+			return false;
+	}
+	return true;
+}
+
+static inline bool TWI_STATUS_SVREAD(uint32_t status) {
+	return (status & TWI_SR_SVREAD) == TWI_SR_SVREAD;
+}
+
+static inline bool TWI_STATUS_SVACC(uint32_t status) {
+	return (status & TWI_SR_SVACC) == TWI_SR_SVACC;
+}
+
+static inline bool TWI_STATUS_GACC(uint32_t status) {
+	return (status & TWI_SR_GACC) == TWI_SR_GACC;
+}
+
+static inline bool TWI_STATUS_EOSACC(uint32_t status) {
+	return (status & TWI_SR_EOSACC) == TWI_SR_EOSACC;
+}
+
+static inline bool TWI_STATUS_NACK(uint32_t status) {
+	return (status & TWI_SR_NACK) == TWI_SR_NACK;
+}
+
+TwoWire::TwoWire(Twi *_twi, void(*_beginCb)(void)) :
+	twi(_twi), rxBufferIndex(0), rxBufferLength(0), txAddress(0),
+			txBufferLength(0), srvBufferIndex(0), srvBufferLength(0), status(
+					UNINITIALIZED), onBeginCallback(_beginCb) {
+	// Empty
+}
+
+void TwoWire::begin(void) {
+	if (onBeginCallback)
+		onBeginCallback();
+
+	// Disable PDC channel
+	twi->TWI_PTCR = UART_PTCR_RXTDIS | UART_PTCR_TXTDIS;
+
+	TWI_ConfigureMaster(twi, TWI_CLOCK, VARIANT_MCK);
+	status = MASTER_IDLE;
+}
+
+void TwoWire::begin(uint8_t address) {
+	if (onBeginCallback)
+		onBeginCallback();
+
+	// Disable PDC channel
+	twi->TWI_PTCR = UART_PTCR_RXTDIS | UART_PTCR_TXTDIS;
+
+	TWI_ConfigureSlave(twi, address);
+	status = SLAVE_IDLE;
+	TWI_EnableIt(twi, TWI_IER_SVACC);
+	//| TWI_IER_RXRDY | TWI_IER_TXRDY	| TWI_IER_TXCOMP);
+}
+
+void TwoWire::begin(int address) {
+	begin((uint8_t) address);
+}
+
+uint8_t TwoWire::requestFrom(uint8_t address, uint8_t quantity, uint8_t sendStop) {
+	if (quantity > BUFFER_LENGTH)
+		quantity = BUFFER_LENGTH;
+
+	// perform blocking read into buffer
+	int readed = 0;
+	TWI_StartRead(twi, address, 0, 0);
+	do {
+		// Stop condition must be set during the reception of last byte
+		if (readed + 1 == quantity)
+			TWI_SendSTOPCondition( twi);
+
+		TWI_WaitByteReceived(twi, RECV_TIMEOUT);
+		rxBuffer[readed++] = TWI_ReadByte(twi);
+	} while (readed < quantity);
+	TWI_WaitTransferComplete(twi, RECV_TIMEOUT);
+
+	// set rx buffer iterator vars
+	rxBufferIndex = 0;
+	rxBufferLength = readed;
+
+	return readed;
+}
+
+uint8_t TwoWire::requestFrom(uint8_t address, uint8_t quantity) {
+	return requestFrom((uint8_t) address, (uint8_t) quantity, (uint8_t) true);
+}
+
+uint8_t TwoWire::requestFrom(int address, int quantity) {
+	return requestFrom((uint8_t) address, (uint8_t) quantity, (uint8_t) true);
+}
+
+uint8_t TwoWire::requestFrom(int address, int quantity, int sendStop) {
+	return requestFrom((uint8_t) address, (uint8_t) quantity, (uint8_t) sendStop);
+}
+
+void TwoWire::beginTransmission(uint8_t address) {
+	status = MASTER_SEND;
+
+	// save address of target and empty buffer
+	txAddress = address;
+	txBufferLength = 0;
+}
+
+void TwoWire::beginTransmission(int address) {
+	beginTransmission((uint8_t) address);
+}
+
+//
+//	Originally, 'endTransmission' was an f(void) function.
+//	It has been modified to take one parameter indicating
+//	whether or not a STOP should be performed on the bus.
+//	Calling endTransmission(false) allows a sketch to
+//	perform a repeated start.
+//
+//	WARNING: Nothing in the library keeps track of whether
+//	the bus tenure has been properly ended with a STOP. It
+//	is very possible to leave the bus in a hung state if
+//	no call to endTransmission(true) is made. Some I2C
+//	devices will behave oddly if they do not see a STOP.
+//
+uint8_t TwoWire::endTransmission(uint8_t sendStop) {
+	// transmit buffer (blocking)
+	TWI_StartWrite(twi, txAddress, 0, 0, txBuffer[0]);
+	TWI_WaitByteSent(twi, XMIT_TIMEOUT);
+	int sent = 1;
+	while (sent < txBufferLength) {
+		TWI_WriteByte(twi, txBuffer[sent++]);
+		TWI_WaitByteSent(twi, XMIT_TIMEOUT);
+	}
+	TWI_Stop( twi);
+	TWI_WaitTransferComplete(twi, XMIT_TIMEOUT);
+
+	// empty buffer
+	txBufferLength = 0;
+
+	status = MASTER_IDLE;
+	return sent;
+}
+
+//	This provides backwards compatibility with the original
+//	definition, and expected behaviour, of endTransmission
+//
+uint8_t TwoWire::endTransmission(void)
+{
+	return endTransmission(true);
+}
+
+size_t TwoWire::write(uint8_t data) {
+	if (status == MASTER_SEND) {
+		if (txBufferLength >= BUFFER_LENGTH)
+			return 0;
+		txBuffer[txBufferLength++] = data;
+		return 1;
+	} else {
+		if (srvBufferLength >= BUFFER_LENGTH)
+			return 0;
+		srvBuffer[srvBufferLength++] = data;
+		return 1;
+	}
+}
+
+size_t TwoWire::write(const uint8_t *data, size_t quantity) {
+	if (status == MASTER_SEND) {
+		for (size_t i = 0; i < quantity; ++i) {
+			if (txBufferLength >= BUFFER_LENGTH)
+				return i;
+			txBuffer[txBufferLength++] = data[i];
+		}
+	} else {
+		for (size_t i = 0; i < quantity; ++i) {
+			if (srvBufferLength >= BUFFER_LENGTH)
+				return i;
+			srvBuffer[srvBufferLength++] = data[i];
+		}
+	}
+	return quantity;
+}
+
+int TwoWire::available(void) {
+	return rxBufferLength - rxBufferIndex;
+}
+
+int TwoWire::read(void) {
+	if (rxBufferIndex < rxBufferLength)
+		return rxBuffer[rxBufferIndex++];
+	return -1;
+}
+
+int TwoWire::peek(void) {
+	if (rxBufferIndex < rxBufferLength)
+		return rxBuffer[rxBufferIndex];
+	return -1;
+}
+
+void TwoWire::flush(void) {
+	// Do nothing, use endTransmission(..) to force
+	// data transfer.
+}
+
+void TwoWire::onReceive(void(*function)(int)) {
+	onReceiveCallback = function;
+}
+
+void TwoWire::onRequest(void(*function)(void)) {
+	onRequestCallback = function;
+}
+
+void TwoWire::onService(void) {
+	// Retrieve interrupt status
+	uint32_t sr = TWI_GetStatus(twi);
+
+	if (status == SLAVE_IDLE && TWI_STATUS_SVACC(sr)) {
+		TWI_DisableIt(twi, TWI_IDR_SVACC);
+		TWI_EnableIt(twi, TWI_IER_RXRDY | TWI_IER_GACC | TWI_IER_NACK
+				| TWI_IER_EOSACC | TWI_IER_SCL_WS | TWI_IER_TXCOMP);
+
+		srvBufferLength = 0;
+		srvBufferIndex = 0;
+
+		// Detect if we should go into RECV or SEND status
+		// SVREAD==1 means *master* reading -> SLAVE_SEND
+		if (!TWI_STATUS_SVREAD(sr)) {
+			status = SLAVE_RECV;
+		} else {
+			status = SLAVE_SEND;
+
+			// Alert calling program to generate a response ASAP
+			if (onRequestCallback)
+				onRequestCallback();
+			else
+				// create a default 1-byte response
+				write((uint8_t) 0);
+		}
+	}
+
+	if (status != SLAVE_IDLE) {
+		if (TWI_STATUS_TXCOMP(sr) && TWI_STATUS_EOSACC(sr)) {
+			if (status == SLAVE_RECV && onReceiveCallback) {
+				// Copy data into rxBuffer
+				// (allows to receive another packet while the
+				// user program reads actual data)
+				for (uint8_t i = 0; i < srvBufferLength; ++i)
+					rxBuffer[i] = srvBuffer[i];
+				rxBufferIndex = 0;
+				rxBufferLength = srvBufferLength;
+
+				// Alert calling program
+				onReceiveCallback( rxBufferLength);
+			}
+
+			// Transfer completed
+			TWI_EnableIt(twi, TWI_SR_SVACC);
+			TWI_DisableIt(twi, TWI_IDR_RXRDY | TWI_IDR_GACC | TWI_IDR_NACK
+					| TWI_IDR_EOSACC | TWI_IDR_SCL_WS | TWI_IER_TXCOMP);
+			status = SLAVE_IDLE;
+		}
+	}
+
+	if (status == SLAVE_RECV) {
+		if (TWI_STATUS_RXRDY(sr)) {
+			if (srvBufferLength < BUFFER_LENGTH)
+				srvBuffer[srvBufferLength++] = TWI_ReadByte(twi);
+		}
+	}
+
+	if (status == SLAVE_SEND) {
+		if (TWI_STATUS_TXRDY(sr) && !TWI_STATUS_NACK(sr)) {
+			uint8_t c = 'x';
+			if (srvBufferIndex < srvBufferLength)
+				c = srvBuffer[srvBufferIndex++];
+			TWI_WriteByte(twi, c);
+		}
+	}
+}
+
+#if WIRE_INTERFACES_COUNT > 0
+static void Wire_Init(void) {
+	pmc_enable_periph_clk(WIRE_INTERFACE_ID);
+	PIO_Configure(
+			g_APinDescription[PIN_WIRE_SDA].pPort,
+			g_APinDescription[PIN_WIRE_SDA].ulPinType,
+			g_APinDescription[PIN_WIRE_SDA].ulPin,
+			g_APinDescription[PIN_WIRE_SDA].ulPinConfiguration);
+	PIO_Configure(
+			g_APinDescription[PIN_WIRE_SCL].pPort,
+			g_APinDescription[PIN_WIRE_SCL].ulPinType,
+			g_APinDescription[PIN_WIRE_SCL].ulPin,
+			g_APinDescription[PIN_WIRE_SCL].ulPinConfiguration);
+
+	NVIC_DisableIRQ(TWI1_IRQn);
+	NVIC_ClearPendingIRQ(TWI1_IRQn);
+	NVIC_SetPriority(TWI1_IRQn, 0);
+	NVIC_EnableIRQ(TWI1_IRQn);
+}
+
+TwoWire Wire = TwoWire(WIRE_INTERFACE, Wire_Init);
+
+void WIRE_ISR_HANDLER(void) {
+	Wire.onService();
+}
+#endif
+
+#if WIRE_INTERFACES_COUNT > 1
+static void Wire1_Init(void) {
+	pmc_enable_periph_clk(WIRE1_INTERFACE_ID);
+	PIO_Configure(
+			g_APinDescription[PIN_WIRE1_SDA].pPort,
+			g_APinDescription[PIN_WIRE1_SDA].ulPinType,
+			g_APinDescription[PIN_WIRE1_SDA].ulPin,
+			g_APinDescription[PIN_WIRE1_SDA].ulPinConfiguration);
+	PIO_Configure(
+			g_APinDescription[PIN_WIRE1_SCL].pPort,
+			g_APinDescription[PIN_WIRE1_SCL].ulPinType,
+			g_APinDescription[PIN_WIRE1_SCL].ulPin,
+			g_APinDescription[PIN_WIRE1_SCL].ulPinConfiguration);
+
+	NVIC_DisableIRQ(TWI0_IRQn);
+	NVIC_ClearPendingIRQ(TWI0_IRQn);
+	NVIC_SetPriority(TWI0_IRQn, 0);
+	NVIC_EnableIRQ(TWI0_IRQn);
+}
+
+TwoWire Wire1 = TwoWire(WIRE1_INTERFACE, Wire1_Init);
+
+void WIRE1_ISR_HANDLER(void) {
+	Wire1.onService();
+}
+#endif