Merge branch 'xmega-twi' of github.com:jamuraa/lufa into xmega-twi-integration

3 files changed, 490 insertions, 0 deletions

diff --git a/LUFA/Drivers/Peripheral/TWI.h b/LUFA/Drivers/Peripheral/TWI.h
index 7782f619a..b17ace95b 100644
--- a/LUFA/Drivers/Peripheral/TWI.h
+++ b/LUFA/Drivers/Peripheral/TWI.h
@@ -66,6 +66,8 @@
 	/* Includes: */
 		#if (ARCH == ARCH_AVR8)
 			#include "AVR8/TWI_AVR8.h"
+		#elif (ARCH == ARCH_XMEGA)
+			#include "XMEGA/TWI_XMEGA.h"
 		#else
 			#error The TWI peripheral driver is not currently available for your selected architecture.
 		#endif
diff --git a/LUFA/Drivers/Peripheral/XMEGA/TWI_XMEGA.c b/LUFA/Drivers/Peripheral/XMEGA/TWI_XMEGA.c
new file mode 100644
index 000000000..81fbd0784
--- /dev/null
+++ b/LUFA/Drivers/Peripheral/XMEGA/TWI_XMEGA.c
@@ -0,0 +1,190 @@
+/*
+             LUFA Library
+     Copyright (C) Dean Camera, 2013.
+
+  dean [at] fourwalledcubicle [dot] com
+           www.lufa-lib.org
+*/
+
+/*
+  Copyright 2013  Dean Camera (dean [at] fourwalledcubicle [dot] com)
+
+  Permission to use, copy, modify, distribute, and sell this
+  software and its documentation for any purpose is hereby granted
+  without fee, provided that the above copyright notice appear in
+  all copies and that both that the copyright notice and this
+  permission notice and warranty disclaimer appear in supporting
+  documentation, and that the name of the author not be used in
+  advertising or publicity pertaining to distribution of the
+  software without specific, written prior permission.
+
+  The author disclaims all warranties with regard to this
+  software, including all implied warranties of merchantability
+  and fitness.  In no event shall the author be liable for any
+  special, indirect or consequential damages or any damages
+  whatsoever resulting from loss of use, data or profits, whether
+  in an action of contract, negligence or other tortious action,
+  arising out of or in connection with the use or performance of
+  this software.
+*/
+
+#include "../../../Common/Common.h"
+#if (ARCH == ARCH_XMEGA)
+
+#define  __INCLUDE_FROM_TWI_C
+#include "../TWI.h"
+
+static inline bool bitmask_is_set(uint8_t byte, uint8_t mask) {
+  return (byte & mask) == mask;
+}
+
+uint8_t TWI_StartTransmission(TWI_t *twi,
+                              const uint8_t SlaveAddress,
+                              const uint8_t TimeoutMS)
+{
+  uint16_t TimeoutRemaining;
+
+  twi->MASTER.ADDR = SlaveAddress;
+
+  TimeoutRemaining = (TimeoutMS * 100);
+  while (TimeoutRemaining)
+  {
+    uint8_t status = twi->MASTER.STATUS;
+    if (bitmask_is_set(status, TWI_MASTER_WIF_bm | TWI_MASTER_ARBLOST_bm))
+    {
+      // Case 1: Arbitration lost.  Try again. (or error)
+      twi->MASTER.ADDR = SlaveAddress;
+    }
+    else if (bitmask_is_set(status, TWI_MASTER_WIF_bm | TWI_MASTER_RXACK_bm))
+    {
+      // Case 2: No response from slave.
+      // We need to release the bus.
+      TWI_StopTransmission(twi);
+      return TWI_ERROR_SlaveResponseTimeout;
+    }
+    else if (status & TWI_MASTER_WIF_bm)
+    {
+      // Case 3: Slave ACK the Write. Ready!
+      return TWI_ERROR_NoError;
+    }
+    else if (status & TWI_MASTER_RIF_bm)
+    {
+      // Case 4: Slave ACK the Read. Ready! (a byte will be read)
+      return TWI_ERROR_NoError;
+    }
+    // Still waiting..
+    _delay_us(10);
+    TimeoutRemaining--;
+  }
+
+  if (!(TimeoutRemaining)) {
+    if (twi->MASTER.STATUS & TWI_MASTER_CLKHOLD_bm) {
+      // Release the bus if we're holding it.
+      TWI_StopTransmission(twi);
+    }
+  }
+  return TWI_ERROR_BusCaptureTimeout;
+}
+
+bool TWI_SendByte(TWI_t *twi, const uint8_t Byte)
+{
+  // We assume we're ready to write!
+  twi->MASTER.DATA = Byte;
+  while (!(twi->MASTER.STATUS & TWI_MASTER_WIF_bm));
+  return (twi->MASTER.STATUS & TWI_MASTER_WIF_bm) && !(twi->MASTER.STATUS & TWI_MASTER_RXACK_bm);
+}
+
+bool TWI_ReceiveByte(TWI_t *twi, uint8_t* const Byte,
+					 const bool LastByte)
+{
+  // If we're here, we should already be reading.  Wait if we haven't read yet.
+  if (bitmask_is_set(twi->MASTER.STATUS, TWI_MASTER_BUSERR_bm | TWI_MASTER_ARBLOST_bm)) {
+    return false;
+  }
+  while (!(twi->MASTER.STATUS & TWI_MASTER_RIF_bm));
+  *Byte = twi->MASTER.DATA;
+  if (LastByte)
+    twi->MASTER.CTRLC = TWI_MASTER_ACKACT_bm | TWI_MASTER_CMD_STOP_gc;
+  else
+    twi->MASTER.CTRLC = TWI_MASTER_CMD_RECVTRANS_gc;
+  return true;
+}
+
+uint8_t TWI_ReadPacket(TWI_t *twi,
+                       const uint8_t SlaveAddress,
+                       const uint8_t TimeoutMS,
+                       const uint8_t* InternalAddress,
+                       uint8_t InternalAddressLen,
+                       uint8_t* Buffer,
+                       uint8_t Length)
+{
+	uint8_t ErrorCode;
+
+	if ((ErrorCode = TWI_StartTransmission(twi, (SlaveAddress & TWI_DEVICE_ADDRESS_MASK) | TWI_ADDRESS_WRITE,
+	                                       TimeoutMS)) == TWI_ERROR_NoError)
+	{
+		while (InternalAddressLen--)
+		{
+			if (!(TWI_SendByte(twi, *(InternalAddress++))))
+			{
+				ErrorCode = TWI_ERROR_SlaveNAK;
+				break;
+			}
+		}
+
+		if ((ErrorCode = TWI_StartTransmission(twi, (SlaveAddress & TWI_DEVICE_ADDRESS_MASK) | TWI_ADDRESS_READ,
+											   TimeoutMS)) == TWI_ERROR_NoError)
+		{
+			while (Length--)
+			{
+				if (!(TWI_ReceiveByte(twi, Buffer++, (Length == 0))))
+				{
+					ErrorCode = TWI_ERROR_SlaveNAK;
+					break;
+				}
+			}
+
+		}
+    TWI_StopTransmission(twi);
+	}
+
+	return ErrorCode;
+}
+
+uint8_t TWI_WritePacket(TWI_t *twi,
+                        const uint8_t SlaveAddress,
+                        const uint8_t TimeoutMS,
+                        const uint8_t* InternalAddress,
+                        uint8_t InternalAddressLen,
+                        const uint8_t* Buffer,
+                        uint8_t Length)
+{
+	uint8_t ErrorCode;
+	if ((ErrorCode = TWI_StartTransmission(twi, (SlaveAddress & TWI_DEVICE_ADDRESS_MASK) | TWI_ADDRESS_WRITE,
+	                                       TimeoutMS)) == TWI_ERROR_NoError)
+	{
+		while (InternalAddressLen--)
+		{
+			if (!(TWI_SendByte(twi, *(InternalAddress++))))
+			{
+				ErrorCode = TWI_ERROR_SlaveNAK;
+				break;
+			}
+		}
+
+		while (Length--)
+		{
+			if (!(TWI_SendByte(twi, *(Buffer++))))
+			{
+				ErrorCode = TWI_ERROR_SlaveNAK;
+				break;
+			}
+		}
+
+		TWI_StopTransmission(twi);
+	}
+
+	return ErrorCode;
+}
+
+#endif
diff --git a/LUFA/Drivers/Peripheral/XMEGA/TWI_XMEGA.h b/LUFA/Drivers/Peripheral/XMEGA/TWI_XMEGA.h
new file mode 100644
index 000000000..0a5d477b2
--- /dev/null
+++ b/LUFA/Drivers/Peripheral/XMEGA/TWI_XMEGA.h
@@ -0,0 +1,298 @@
+/*
+             LUFA Library
+     Copyright (C) Dean Camera, 2013.
+
+  dean [at] fourwalledcubicle [dot] com
+           www.lufa-lib.org
+*/
+
+/*
+  Copyright 2013  Dean Camera (dean [at] fourwalledcubicle [dot] com)
+
+  Permission to use, copy, modify, distribute, and sell this
+  software and its documentation for any purpose is hereby granted
+  without fee, provided that the above copyright notice appear in
+  all copies and that both that the copyright notice and this
+  permission notice and warranty disclaimer appear in supporting
+  documentation, and that the name of the author not be used in
+  advertising or publicity pertaining to distribution of the
+  software without specific, written prior permission.
+
+  The author disclaims all warranties with regard to this
+  software, including all implied warranties of merchantability
+  and fitness.  In no event shall the author be liable for any
+  special, indirect or consequential damages or any damages
+  whatsoever resulting from loss of use, data or profits, whether
+  in an action of contract, negligence or other tortious action,
+  arising out of or in connection with the use or performance of
+  this software.
+*/
+
+/** \file
+ *  \brief TWI Peripheral Driver (XMEGA)
+ *
+ *  On-chip TWI driver for the XMEGA Family of AVR microcontrollers.
+ *
+ *  \note This file should not be included directly. It is automatically included as needed by the TWI driver
+ *        dispatch header located in LUFA/Drivers/Peripheral/TWI.h.
+ */
+
+/** \ingroup Group_TWI
+ *  \defgroup Group_TWI_XMEGA TWI Peripheral Driver (XMEGA)
+ *
+ *  \section Sec_TWI_XMEGA_ModDescription Module Description
+ *  Master mode TWI driver for the 8-bit AVR microcontrollers which contain a hardware TWI module.
+ *
+ *  \note This file should not be included directly. It is automatically included as needed by the TWI driver
+ *        dispatch header located in LUFA/Drivers/Peripheral/TWI.h.
+ *
+ *  \section Sec_TWI_XMEGA_ExampleUsage Example Usage
+ *  The following snippet is an example of how this module may be used within a typical
+ *  application.
+ *
+ *  <b>Low Level API Example:</b>
+ *  \code
+ *      // Initialize the TWI driver before first use at 200KHz
+ *      TWI_Init(&TWIC, TWI_BAUD_FROM_FREQ(200000));
+ *
+ *      // Start a write session to device at device address 0xA0, internal address 0xDC with a 10ms timeout
+ *      if (TWI_StartTransmission(&TWIC, 0xA0 | TWI_ADDRESS_WRITE, 10) == TWI_ERROR_NoError)
+ *      {
+ *          TWI_SendByte(&TWIC, 0xDC);
+ *
+ *          TWI_SendByte(&TWIC, 0x01);
+ *          TWI_SendByte(&TWIC, 0x02);
+ *          TWI_SendByte(&TWIC, 0x03);
+ *
+ *          // Must stop transmission afterwards to release the bus
+ *          TWI_StopTransmission(&TWIC);
+ *      }
+ *
+ *      // Start a read session to device at address 0xA0, internal address 0xDC with a 10ms timeout
+ *      if (TWI_StartTransmission(&TWIC, 0xA0 | TWI_ADDRESS_WRITE, 10) == TWI_ERROR_NoError)
+ *      {
+ *          TWI_SendByte(&TWIC, 0xDC);
+ *          TWI_StopTransmission(&TWIC);
+ *
+ *          if (TWI_StartTransmission(&TWIC, 0xA0 | TWI_ADDRESS_READ, 10) == TWI_ERROR_NoError)
+ *          {
+ *              uint8_t Byte1, Byte2, Byte3;
+ *
+ *              // Read three bytes, acknowledge after the third byte is received
+ *              TWI_ReceiveByte(&TWIC, &Byte1, false);
+ *              TWI_ReceiveByte(&TWIC, &Byte2, false);
+ *              TWI_ReceiveByte(&TWIC, &Byte3, true);
+ *
+ *              // Must stop transmission afterwards to release the bus
+ *              TWI_StopTransmission(&TWIC);
+ *          }
+ *      }
+ *  \endcode
+ *
+ *  <b>High Level API Example:</b>
+ *  \code
+ *      // Initialize the TWI driver before first use at 200KHz
+ *      TWI_Init(&TWIC, TWI_BAUD_FROM_FREQ(200000));
+ *
+ *      // Start a write session to device at device address 0xA0, internal address 0xDC with a 10ms timeout
+ *      uint8_t InternalWriteAddress = 0xDC;
+ *      uint8_t WritePacket[3] = {0x01, 0x02, 0x03};
+ *
+ *      TWI_WritePacket(&TWIC, 0xA0, 10, &InternalWriteAddress, sizeof(InternalWriteAddress),
+ *                      &WritePacket, sizeof(WritePacket);
+ *
+ *      // Start a read session to device at address 0xA0, internal address 0xDC with a 10ms timeout
+ *      uint8_t InternalReadAddress = 0xDC;
+ *      uint8_t ReadPacket[3];
+ *
+ *      TWI_ReadPacket(&TWIC, 0xA0, 10, &InternalReadAddress, sizeof(InternalReadAddress),
+ *                     &ReadPacket, sizeof(ReadPacket);
+ *  \endcode
+ *
+ *  @{
+ */
+
+#ifndef __TWI_XMEGA_H__
+#define __TWI_XMEGA_H__
+
+	/* Includes: */
+		#include "../../../Common/Common.h"
+
+		#include <stdio.h>
+
+	/* Enable C linkage for C++ Compilers: */
+		#if defined(__cplusplus)
+			extern "C" {
+		#endif
+
+	/* Preprocessor Checks: */
+		#if !defined(__INCLUDE_FROM_TWI_H) && !defined(__INCLUDE_FROM_TWI_C)
+			#error Do not include this file directly. Include LUFA/Drivers/Peripheral/TWI.h instead.
+		#endif
+
+	/* Public Interface - May be used in end-application: */
+		/* Macros: */
+			/** TWI slave device address mask for a read session. Mask with a slave device base address to obtain
+			 *  the correct TWI bus address for the slave device when reading data from it.
+			 */
+			#define TWI_ADDRESS_READ         0x01
+
+			/** TWI slave device address mask for a write session. Mask with a slave device base address to obtain
+			 *  the correct TWI bus address for the slave device when writing data to it.
+			 */
+			#define TWI_ADDRESS_WRITE        0x00
+
+			/** Mask to retrieve the base address for a TWI device, which can then be ORed with \ref TWI_ADDRESS_READ
+			 *  or \ref TWI_ADDRESS_WRITE to obtain the device's read and write address respectively.
+			 */
+			#define TWI_DEVICE_ADDRESS_MASK  0xFE
+
+			/** Calculates the length of each bit on the TWI bus for a given target frequency. This may be used with
+			 *  the \ref TWI_Init() function to convert a bus frequency to a number of clocks for the \c BitLength
+			 *  parameter.
+			 *
+			 *  \param[in] Frequency  Desired TWI bus frequency in Hz.
+			 *
+			 *  \return Bit length in clocks for the given TWI bus frequency at the given prescaler value.
+			 */
+			#define TWI_BAUD_FROM_FREQ(Frequency) ((F_CPU / (2 * Frequency)) - 5)
+
+		/* Enums: */
+			/** Enum for the possible return codes of the TWI transfer start routine and other dependant TWI functions. */
+			enum TWI_ErrorCodes_t
+			{
+				TWI_ERROR_NoError              = 0, /**< Indicates that the command completed successfully. */
+				TWI_ERROR_BusFault             = 1, /**< A TWI bus fault occurred while attempting to capture the bus. */
+				TWI_ERROR_BusCaptureTimeout    = 2, /**< A timeout occurred whilst waiting for the bus to be ready. */
+				TWI_ERROR_SlaveResponseTimeout = 3, /**< No ACK received at the nominated slave address within the timeout period. */
+				TWI_ERROR_SlaveNotReady        = 4, /**< Slave NAKed the TWI bus START condition. */
+				TWI_ERROR_SlaveNAK             = 5, /**< Slave NAKed whilst attempting to send data to the device. */
+			};
+
+		/* Inline Functions: */
+			/** Initializes the TWI hardware into master mode, ready for data transmission and reception. This must be
+			 *  before any other TWI operations.
+			 *
+			 *  The generated SCL frequency will be according to the formula <pre>F_CPU / (2 * (5 + (BAUD)))</pre>.
+			 *
+			 *  \attention The value of the \c BitLength parameter should not be set below 10 or invalid bus conditions may
+			 *             occur, as indicated in the XMEGA microcontroller datasheet.
+			 *
+       *  \param[in] twi        The TWI Peripheral to use
+			 *  \param[in] Baud       Value of the BAUD register of the TWI Master.
+			 */
+			static inline void TWI_Init(TWI_t *twi, const uint8_t Baud) ATTR_ALWAYS_INLINE ATTR_NON_NULL_PTR_ARG(1);
+			static inline void TWI_Init(TWI_t *twi, const uint8_t Baud)
+			{
+        twi->CTRL = 0x00;
+        twi->MASTER.BAUD = Baud;
+        twi->MASTER.CTRLA = TWI_MASTER_ENABLE_bm;
+        twi->MASTER.CTRLB = 0;
+        twi->MASTER.STATUS = TWI_MASTER_BUSSTATE_IDLE_gc;
+			}
+
+			/** Turns off the TWI driver hardware. If this is called, any further TWI operations will require a call to
+			 *  \ref TWI_Init() before the TWI can be used again.
+       *
+       *  \param[in] twi        The TWI Peripheral to use
+			 */
+			static inline void TWI_Disable(TWI_t *twi) ATTR_ALWAYS_INLINE ATTR_NON_NULL_PTR_ARG(1);
+			static inline void TWI_Disable(TWI_t *twi)
+			{
+        twi->MASTER.CTRLA &= ~TWI_MASTER_ENABLE_bm;
+			}
+
+			/** Sends a TWI STOP onto the TWI bus, terminating communication with the currently addressed device. 
+       *
+       *  \param[in] twi        The TWI Peripheral to use
+       */
+			static inline void TWI_StopTransmission(TWI_t *twi) ATTR_ALWAYS_INLINE ATTR_NON_NULL_PTR_ARG(1);
+			static inline void TWI_StopTransmission(TWI_t *twi)
+			{
+        twi->MASTER.CTRLC = TWI_MASTER_ACKACT_bm | TWI_MASTER_CMD_STOP_gc;
+			}
+
+		/* Function Prototypes: */
+			/** Begins a master mode TWI bus communication with the given slave device address.
+			 *
+       *  \param[in] twi                 The TWI Peripheral to use
+			 *  \param[in] SlaveAddress  Address of the slave TWI device to communicate with.
+			 *  \param[in] TimeoutMS     Timeout period within which the slave must respond, in milliseconds.
+			 *
+			 *  \return A value from the \ref TWI_ErrorCodes_t enum.
+			 */
+			uint8_t TWI_StartTransmission(TWI_t *twi,
+                                    const uint8_t SlaveAddress,
+			                              const uint8_t TimeoutMS) ATTR_NON_NULL_PTR_ARG(1);
+
+			/** Sends a byte to the currently addressed device on the TWI bus.
+			 *
+       *  \param[in] twi                 The TWI Peripheral to use
+			 *  \param[in] Byte  Byte to send to the currently addressed device
+			 *
+			 *  \return Boolean \c true if the recipient ACKed the byte, \c false otherwise
+			 */
+			bool TWI_SendByte(TWI_t *twi, const uint8_t Byte) ATTR_NON_NULL_PTR_ARG(1);
+
+			/** Receives a byte from the currently addressed device on the TWI bus.
+			 *
+       *  \param[in] twi                 The TWI Peripheral to use
+			 *  \param[in] Byte      Location where the read byte is to be stored.
+			 *  \param[in] LastByte  Indicates if the byte should be ACKed if false, NAKed if true.
+			 *
+			 *  \return Boolean \c true if the byte reception successfully completed, \c false otherwise.
+			 */
+			bool TWI_ReceiveByte(TWI_t *twi, uint8_t* const Byte,
+			                     const bool LastByte) ATTR_NON_NULL_PTR_ARG(1, 2);
+
+			/** High level function to perform a complete packet transfer over the TWI bus to the specified
+			 *  device.
+			 *
+       *  \param[in] twi                 The TWI Peripheral to use
+			 *  \param[in] SlaveAddress        Base address of the TWI slave device to communicate with.
+			 *  \param[in] TimeoutMS           Timeout for bus capture and slave START ACK, in milliseconds.
+			 *  \param[in] InternalAddress     Pointer to a location where the internal slave read start address is stored.
+			 *  \param[in] InternalAddressLen  Size of the internal device address, in bytes.
+			 *  \param[in] Buffer              Pointer to a buffer where the read packet data is to be stored.
+			 *  \param[in] Length              Size of the packet to read, in bytes.
+			 *
+			 *  \return A value from the \ref TWI_ErrorCodes_t enum.
+			 */
+			uint8_t TWI_ReadPacket(TWI_t *twi,
+                             const uint8_t SlaveAddress,
+			                       const uint8_t TimeoutMS,
+			                       const uint8_t* InternalAddress,
+			                       uint8_t InternalAddressLen,
+			                       uint8_t* Buffer,
+			                       uint8_t Length) ATTR_NON_NULL_PTR_ARG(1, 4);
+
+			/** High level function to perform a complete packet transfer over the TWI bus from the specified
+			 *  device.
+			 *
+       *  \param[in] twi                 The TWI Peripheral to use
+			 *  \param[in] SlaveAddress        Base address of the TWI slave device to communicate with
+			 *  \param[in] TimeoutMS           Timeout for bus capture and slave START ACK, in milliseconds
+			 *  \param[in] InternalAddress     Pointer to a location where the internal slave write start address is stored
+			 *  \param[in] InternalAddressLen  Size of the internal device address, in bytes
+			 *  \param[in] Buffer              Pointer to a buffer where the packet data to send is stored
+			 *  \param[in] Length              Size of the packet to send, in bytes
+			 *
+			 *  \return A value from the \ref TWI_ErrorCodes_t enum.
+			 */
+			uint8_t TWI_WritePacket(TWI_t *twi,
+                              const uint8_t SlaveAddress,
+			                        const uint8_t TimeoutMS,
+			                        const uint8_t* InternalAddress,
+			                        uint8_t InternalAddressLen,
+			                        const uint8_t* Buffer,
+			                        uint8_t Length) ATTR_NON_NULL_PTR_ARG(1, 4);
+
+	/* Disable C linkage for C++ Compilers: */
+		#if defined(__cplusplus)
+			}
+		#endif
+
+#endif
+
+/** @} */
+