Diff: i2c_api.h

Revision:

3:768173a57492

Parent:

0:e1a608bb55e8

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/i2c_api.h	Wed Jul 13 15:12:06 2016 +0100
@@ -0,0 +1,223 @@
+/* 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