LUFA/Drivers/Peripheral/AVR32/SPI.h

   1 /*
   2              LUFA Library
   3      Copyright (C) Dean Camera, 2010.
   4
   5   dean [at] fourwalledcubicle [dot] com
   6       www.fourwalledcubicle.com
   7 */
   8
   9 /*
  10   Copyright 2010  Dean Camera (dean [at] fourwalledcubicle [dot] com)
  11
  12   Permission to use, copy, modify, distribute, and sell this
  13   software and its documentation for any purpose is hereby granted
  14   without fee, provided that the above copyright notice appear in
  15   all copies and that both that the copyright notice and this
  16   permission notice and warranty disclaimer appear in supporting
  17   documentation, and that the name of the author not be used in
  18   advertising or publicity pertaining to distribution of the
  19   software without specific, written prior permission.
  20
  21   The author disclaim all warranties with regard to this
  22   software, including all implied warranties of merchantability
  23   and fitness.  In no event shall the author be liable for any
  24   special, indirect or consequential damages or any damages
  25   whatsoever resulting from loss of use, data or profits, whether
  26   in an action of contract, negligence or other tortious action,
  27   arising out of or in connection with the use or performance of
  28   this software.
  29 */
  30
  31 /** \file
  32  *
  33  *  SPI driver for the 32-bit AVRs.
  34  *
  35  *  \note This file should not be included directly. It is automatically included as needed by the SPI driver
  36  *        dispatch header located in LUFA/Drivers/Peripheral/SPI.h.
  37  */
  38
  39 /** \ingroup Group_SPI
  40  *  @defgroup Group_SPI_AVR32 32-Bit AVR SPI Driver
  41  *
  42  *  SPI driver for the 32-bit AVRs.
  43  *
  44  *  \note This file should not be included directly. It is automatically included as needed by the ADC driver
  45  *        dispatch header located in LUFA/Drivers/Peripheral/SPI.h.
  46  *
  47  *  @{
  48  */
  49
  50 #ifndef __SPI_AVR32_H__
  51 #define __SPI_AVR32_H__
  52
  53         /* Includes: */
  54                 #include <avr32/io.h>
  55                 #include <stdbool.h>
  56
  57         /* Preprocessor Checks: */
  58                 #if !defined(__INCLUDE_FROM_SPI_H)
  59                         #error Do not include this file directly. Include LUFA/Drivers/Peripheral/SPI.h instead.
  60                 #endif
  61
  62         /* Enable C linkage for C++ Compilers: */
  63                 #if defined(__cplusplus)
  64                         extern "C" {
  65                 #endif
  66
  67         /* Public Interface - May be used in end-application: */
  68                 /* Macros: */
  69                         /** SPI prescaler mask for SPI_Init(). Divides the system clock by a factor of 1. */
  70                         #define SPI_SPEED_FCPU_DIV_1           0
  71
  72                         /** SPI prescaler mask for SPI_Init(). Divides the system clock by a factor of 32. */
  73                         #define SPI_SPEED_FCPU_DIV_32          AVR32_SPI_MR_FDIV_MASK
  74
  75                         /** SPI mode mask for SPI_Init(). Indicates that the SPI interface should be initialized into slave mode. */
  76                         #define SPI_MODE_SLAVE                 0
  77
  78                         /** SPI mode mask for SPI_Init(). Indicates that the SPI interface should be initialized into master mode. */
  79                         #define SPI_MODE_MASTER                AVR32_SPI_MR_MSTR_MASK
  80
  81                 /* Inline Functions: */
  82                         /** Initialises the SPI subsystem, ready for transfers. Must be called before calling any other
  83                          *  SPI routines.
  84                          *
  85                          *  \param[in] SPIOptions  SPI Options, a mask consisting of one of each of the SPI_SPEED_*
  86                          *                         and SPI_MODE_* masks
  87                          */
  88                         static inline void SPI_Init(const uint8_t SPIOptions)
  89                         {
  90                                 AVR32_SPI.cr = AVR32_SPI_CR_SPIEN_MASK | AVR32_SPI_CR_SWRST_MASK;
  91                                 AVR32_SPI.mr = SPIOptions;
  92                         }
  93
  94                         /** Turns off the SPI driver, disabling and returning used hardware to their default configuration. */
  95                         static inline void SPI_ShutDown(void)
  96                         {
  97                                 AVR32_SPI.cr = AVR32_SPI_CR_SPIDIS_MASK;
  98                         }
  99
 100                         /** Sends and receives a byte through the SPI interface, blocking until the transfer is complete.
 101                          *
 102                          *  \param[in] Byte  Byte to send through the SPI interface
 103                          *
 104                          *  \return Response byte from the attached SPI device
 105                          */
 106                         static inline uint8_t SPI_TransferByte(const uint8_t Byte) ATTR_ALWAYS_INLINE;
 107                         static inline uint8_t SPI_TransferByte(const uint8_t Byte)
 108                         {
 109                                 AVR32_SPI.tdr = Byte;
 110                                 // TODO: Wait for receive
 111                                 return AVR32_SPI.rdr;
 112                         }
 113
 114                         /** Sends a byte through the SPI interface, blocking until the transfer is complete. The response
 115                          *  byte sent to from the attached SPI device is ignored.
 116                          *
 117                          *  \param[in] Byte Byte to send through the SPI interface
 118                          */
 119                         static inline void SPI_SendByte(const uint8_t Byte) ATTR_ALWAYS_INLINE;
 120                         static inline void SPI_SendByte(const uint8_t Byte)
 121                         {
 122                                 AVR32_SPI.tdr = Byte;
 123                                 // TODO: Wait for receive
 124                         }
 125
 126                         /** Sends a dummy byte through the SPI interface, blocking until the transfer is complete. The response
 127                          *  byte from the attached SPI device is returned.
 128                          *
 129                          *  \return The response byte from the attached SPI device
 130                          */
 131                         static inline uint8_t SPI_ReceiveByte(void) ATTR_ALWAYS_INLINE ATTR_WARN_UNUSED_RESULT;
 132                         static inline uint8_t SPI_ReceiveByte(void)
 133                         {
 134                                 AVR32_SPI.tdr = 0x00;
 135                                 // TODO: Wait for receive
 136                                 return AVR32_SPI.rdr;
 137                         }
 138
 139         /* Disable C linkage for C++ Compilers: */
 140                 #if defined(__cplusplus)
 141                         }
 142                 #endif
 143
 144 #endif
 145
 146 /** @} */