diff options
Diffstat (limited to 'wirish/comm/HardwareSPI.h')
| -rw-r--r-- | wirish/comm/HardwareSPI.h | 178 |
1 files changed, 153 insertions, 25 deletions
diff --git a/wirish/comm/HardwareSPI.h b/wirish/comm/HardwareSPI.h index 7241d0b..3a6def5 100644 --- a/wirish/comm/HardwareSPI.h +++ b/wirish/comm/HardwareSPI.h @@ -3,60 +3,188 @@ * * Copyright (c) 2010 Perry Hung. * - * 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 + * 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 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. + * 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. *****************************************************************************/ /** - * @brief HardwareSPI definitions + * @file HardwareSPI.h + * @brief High-level SPI interface + * + * This is a "bare essentials" polling driver for now. */ +/* TODO [0.1.0] Remove deprecated methods. */ + +#include "libmaple_types.h" +#include "spi.h" + +#include "boards.h" + #ifndef _HARDWARESPI_H_ #define _HARDWARESPI_H_ /** - * Defines the possible SPI communication speeds. + * @brief Defines the possible SPI communication speeds. */ typedef enum SPIFrequency { SPI_18MHZ = 0, /**< 18 MHz */ SPI_9MHZ = 1, /**< 9 MHz */ SPI_4_5MHZ = 2, /**< 4.5 MHz */ - SPI_2_25MHZ = 3, /**< 2.25 MHZ */ + SPI_2_25MHZ = 3, /**< 2.25 MHz */ SPI_1_125MHZ = 4, /**< 1.125 MHz */ SPI_562_500KHZ = 5, /**< 562.500 KHz */ SPI_281_250KHZ = 6, /**< 281.250 KHz */ SPI_140_625KHZ = 7, /**< 140.625 KHz */ - MAX_SPI_FREQS = 8, /**< The number of SPI frequencies. */ } SPIFrequency; -/* Documented by hand in docs/source/lang/api/hardwarespi.rst; if you - make any changes, make sure to update this document. */ +#define MAX_SPI_FREQS 8 + +#if CYCLES_PER_MICROSECOND != 72 +/* TODO [0.2.0?] something smarter than this */ +#warn "Unexpected clock speed; SPI frequency calculation will be incorrect" +#endif + +/** + * @brief Wirish SPI interface. + * + * This implementation uses software slave management, so the caller + * is responsible for controlling the slave select line. + */ class HardwareSPI { - private: - uint32 spi_num; +public: + /** + * @param spiPortNumber Number of the SPI port to manage. + */ + HardwareSPI(uint32 spiPortNumber); + + /** + * @brief Turn on a SPI port and set its GPIO pin modes for use as master. + * + * SPI port is enabled in full duplex mode, with software slave management. + * + * @param frequency Communication frequency + * @param bitOrder Either LSBFIRST (little-endian) or MSBFIRST (big-endian) + * @param mode SPI mode to use, one of SPI_MODE_0, SPI_MODE_1, + * SPI_MODE_2, and SPI_MODE_3. + */ + void begin(SPIFrequency frequency, uint32 bitOrder, uint32 mode); - public: - HardwareSPI(uint32 spi_num); + /** + * @brief Equivalent to begin(SPI_1_125MHZ, MSBFIRST, 0). + */ void begin(void); - void begin(SPIFrequency freq, uint32 endianness, uint32 mode); + + /** + * @brief Turn on a SPI port and set its GPIO pin modes for use as a slave. + * + * SPI port is enabled in full duplex mode, with software slave management. + * + * @param bitOrder Either LSBFIRST (little-endian) or MSBFIRST(big-endian) + * @param mode SPI mode to use + */ + void beginSlave(uint32 bitOrder, uint32 mode); + + /** + * @brief Equivalent to beginSlave(MSBFIRST, 0). + */ + void beginSlave(void); + + /** + * @brief Disables the SPI port, but leaves its GPIO pin modes unchanged. + */ + void end(void); + + /** + * @brief Return the next unread byte. + * + * If there is no unread byte waiting, this function will block + * until one is received. + */ + uint8 read(void); + + /** + * @brief Read length bytes, storing them into buffer. + * @param buffer Buffer to store received bytes into. + * @param length Number of bytes to store in buffer. This + * function will block until the desired number of + * bytes have been read. + */ + void read(uint8 *buffer, uint32 length); + + /** + * @brief Transmit a byte. + * @param data Byte to transmit. + */ + void write(uint8 data); + + /** + * @brief Transmit multiple bytes. + * @param buffer Bytes to transmit. + * @param length Number of bytes in buffer to transmit. + */ + void write(const uint8 *buffer, uint32 length); + + /** + * @brief Transmit a byte, then return the next unread byte. + * + * This function transmits before receiving. + * + * @param data Byte to transmit. + * @return Next unread byte. + */ + uint8 transfer(uint8 data); + + /* -- The following methods are deprecated --------------------------- */ + + /** + * @brief Deprecated. + * + * Use HardwareSPI::transfer() instead. + * + * @see HardwareSPI::transfer() + */ uint8 send(uint8 data); + + /** + * @brief Deprecated. + * + * Use HardwareSPI::write() in combination with + * HardwareSPI::read() (or HardwareSPI::transfer()) instead. + * + * @see HardwareSPI::write() + * @see HardwareSPI::read() + * @see HardwareSPI::transfer() + */ uint8 send(uint8 *data, uint32 length); + + /** + * @brief Deprecated. + * + * Use HardwareSPI::read() instead. + * + * @see HardwareSPI::read() + */ uint8 recv(void); +private: + spi_dev *spi_d; }; #endif |