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/* mbed Microcontroller Library
* 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.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef MBED_I2C_API_H
#define MBED_I2C_API_H
#include "device.h"
#include "buffer.h"
#if DEVICE_I2C
/**
* @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
enum {
I2C_ERROR_NO_SLAVE = -1,
I2C_ERROR_BUS_BUSY = -2
};
#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
/**
* \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);
/** 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, const 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
#endif
#endif
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