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Diff: hal/i2c_api.h
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- 0:f269e3021894
diff -r 000000000000 -r f269e3021894 hal/i2c_api.h --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/hal/i2c_api.h Sun Oct 23 15:10:02 2016 +0000 @@ -0,0 +1,246 @@ + +/** \addtogroup hal */ +/** @{*/ +/* 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 "hal/buffer.h" + +#if DEVICE_I2C_ASYNCH +#include "hal/dma_api.h" +#endif + +#if DEVICE_I2C + +/** + * @defgroup hal_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 hal_GeneralI2C I2C Configuration Functions + * @{ + */ + +/** Initialize the I2C peripheral. It sets the default parameters for I2C + * peripheral, and configures 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 write + * @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 0 if NAK was received, 1 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 hal_AsynchI2C Asynchronous I2C Hardware Abstraction Layer + * @{ + */ + +/** Start I2C asynchronous transfer + * + * @param obj The I2C object + * @param tx The transmit buffer + * @param tx_length The number of bytes to transmit + * @param rx The receive buffer + * @param rx_length The number of bytes to receive + * @param address The address to be set - 7bit or 9bit + * @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, otherwise return 0. + */ +uint32_t i2c_irq_handler_asynch(i2c_t *obj); + +/** Attempts to determine if the 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 asynchronous transfer + * + * This function does not perform any check - that should happen in upper layers. + * @param obj The I2C object + */ +void i2c_abort_asynch(i2c_t *obj); + +#endif + +/**@}*/ + +#ifdef __cplusplus +} +#endif + +#endif + +#endif + +/** @}*/