Lancaster University's (short term!) clone of mbed-src for micro:bit. This is a copy of the github branch https://github.com/lancaster-university/mbed-classic
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Diff: hal/i2c_api.h
- Revision:
- 525:c320967f86b9
- Parent:
- 470:07f8455214b5
- Child:
- 563:536c9fb088a0
--- a/hal/i2c_api.h Mon Apr 27 09:45:08 2015 +0100 +++ b/hal/i2c_api.h Tue Apr 28 11:45:12 2015 +0100 @@ -1,5 +1,5 @@ /* mbed Microcontroller Library - * Copyright (c) 2006-2013 ARM Limited + * Copyright (c) 2006-2015 ARM Limited * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. @@ -17,40 +17,203 @@ #define MBED_I2C_API_H #include "device.h" +#include "buffer.h" #if DEVICE_I2C -#ifdef __cplusplus -extern "C" { +/** + * @defgroup I2CEvents I2C Events Macros + * + * @{ + */ +#define I2C_EVENT_ERROR (1 << 1) +#define I2C_EVENT_ERROR_NO_SLAVE (1 << 2) +#define I2C_EVENT_TRANSFER_COMPLETE (1 << 3) +#define I2C_EVENT_TRANSFER_EARLY_NACK (1 << 4) +#define I2C_EVENT_ALL (I2C_EVENT_ERROR | I2C_EVENT_TRANSFER_COMPLETE | I2C_EVENT_ERROR_NO_SLAVE | I2C_EVENT_TRANSFER_EARLY_NACK) + +/**@}*/ + +#if DEVICE_I2C_ASYNCH +/** Asynch i2c hal structure + */ +typedef struct { + struct i2c_s i2c; /**< Target specific i2c structure */ + struct buffer_s tx_buff; /**< Tx buffer */ + struct buffer_s rx_buff; /**< Rx buffer */ +} i2c_t; + +#else +/** Non-asynch i2c hal structure + */ +typedef struct i2c_s i2c_t; + #endif -typedef struct i2c_s i2c_t; - enum { I2C_ERROR_NO_SLAVE = -1, I2C_ERROR_BUS_BUSY = -2 }; -void i2c_init (i2c_t *obj, PinName sda, PinName scl); -void i2c_frequency (i2c_t *obj, int hz); -int i2c_start (i2c_t *obj); -int i2c_stop (i2c_t *obj); -int i2c_read (i2c_t *obj, int address, char *data, int length, int stop); -int i2c_write (i2c_t *obj, int address, const char *data, int length, int stop); -void i2c_reset (i2c_t *obj); -int i2c_byte_read (i2c_t *obj, int last); -int i2c_byte_write (i2c_t *obj, int data); +#ifdef __cplusplus +extern "C" { +#endif + +/** + * \defgroup GeneralI2C I2C Configuration Functions + * @{ + */ + +/** Initialize the I2C peripheral. It sets the default parameters for I2C + * peripheral, and configure its specifieds pins. + * @param obj The i2c object + * @param sda The sda pin + * @param scl The scl pin + */ +void i2c_init(i2c_t *obj, PinName sda, PinName scl); + +/** Configure the I2C frequency. + * @param obj The i2c object + * @param hz Frequency in Hz + */ +void i2c_frequency(i2c_t *obj, int hz); + +/** Send START command. + * @param obj The i2c object + */ +int i2c_start(i2c_t *obj); + +/** Send STOP command. + * @param obj The i2c object + */ +int i2c_stop(i2c_t *obj); + +/** Blocking reading data. + * @param obj The i2c object + * @param address 7-bit address (last bit is 1) + * @param data The buffer for receiving + * @param length Number of bytes to read + * @param stop Stop to be generated after the transfer is done + * @return Number of read bytes + */ +int i2c_read(i2c_t *obj, int address, char *data, int length, int stop); + +/** Blocking sending data. + * @param obj The i2c object + * @param address 7-bit address (last bit is 0) + * @param data The buffer for sending + * @param length Number of bytes to wrte + * @param stop Stop to be generated after the transfer is done + * @return Number of written bytes + */ +int i2c_write(i2c_t *obj, int address, const char *data, int length, int stop); + +/** Reset I2C peripheral. TODO: The action here. Most of the implementation sends stop(). + * @param obj The i2c object + */ +void i2c_reset(i2c_t *obj); + +/** Read one byte. + * @param obj The i2c object + * @param last Acknoledge + * @return The read byte + */ +int i2c_byte_read(i2c_t *obj, int last); + +/** Write one byte. + * @param obj The i2c object + * @param data Byte to be written + * @return 1 if NAK was received, 0 if ACK was received, 2 for timeout. + */ +int i2c_byte_write(i2c_t *obj, int data); + +/**@}*/ #if DEVICE_I2CSLAVE -void i2c_slave_mode (i2c_t *obj, int enable_slave); + +/** + * \defgroup SynchI2C Synchronous I2C Hardware Abstraction Layer for slave + * @{ + */ + +/** Configure I2C as slave or master. + * @param obj The I2C object + * @return non-zero if a value is available + */ +void i2c_slave_mode(i2c_t *obj, int enable_slave); + +/** Check to see if the I2C slave has been addressed. + * @param obj The I2C object + * @return The status - 1 - read addresses, 2 - write to all slaves, + * 3 write addressed, 0 - the slave has not been addressed + */ int i2c_slave_receive(i2c_t *obj); -int i2c_slave_read (i2c_t *obj, char *data, int length); -int i2c_slave_write (i2c_t *obj, const char *data, int length); -int i2c_slave_byte_read(i2c_t *obj, int last); -int i2c_slave_byte_write(i2c_t *obj, int data); + +/** Configure I2C as slave or master. + * @param obj The I2C object + * @return non-zero if a value is available + */ +int i2c_slave_read(i2c_t *obj, char *data, int length); + +/** Configure I2C as slave or master. + * @param obj The I2C object + * @return non-zero if a value is available + */ +int i2c_slave_write(i2c_t *obj, const char *data, int length); + +/** Configure I2C address. + * @param obj The I2C object + * @param idx Currently not used + * @param address The address to be set + * @param mask Currently not used + */ void i2c_slave_address(i2c_t *obj, int idx, uint32_t address, uint32_t mask); + #endif +/**@}*/ + +#if DEVICE_I2C_ASYNCH + +/** + * \defgroup AsynchI2C Asynchronous I2C Hardware Abstraction Layer + * @{ + */ + +/** Start i2c asynchronous transfer. + * @param obj The I2C object + * @param tx The buffer to send + * @param tx_length The number of words to transmit + * @param rx The buffer to receive + * @param rx_length The number of words to receive + * @param address The address to be set - 7bit or 9 bit + * @param stop If true, stop will be generated after the transfer is done + * @param handler The I2C IRQ handler to be set + * @param hint DMA hint usage + */ +void i2c_transfer_asynch(i2c_t *obj, void *tx, size_t tx_length, void *rx, size_t rx_length, uint32_t address, uint32_t stop, uint32_t handler, uint32_t event, DMAUsage hint); + +/** The asynchronous IRQ handler + * @param obj The I2C object which holds the transfer information + * @return event flags if a transfer termination condition was met or 0 otherwise. + */ +uint32_t i2c_irq_handler_asynch(i2c_t *obj); + +/** Attempts to determine if I2C peripheral is already in use. + * @param obj The I2C object + * @return non-zero if the I2C module is active or zero if it is not + */ +uint8_t i2c_active(i2c_t *obj); + +/** Abort ongoing asynchronous transaction. + * @param obj The I2C object + */ +void i2c_abort_asynch(i2c_t *obj); + +#endif + +/**@}*/ + #ifdef __cplusplus } #endif