Amit Gandhi
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Diff: targets/TARGET_Maxim/TARGET_MAX32625/mxc/i2cm.c
- Revision:
- 150:02e0a0aed4ec
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/targets/TARGET_Maxim/TARGET_MAX32625/mxc/i2cm.c Tue Nov 08 17:45:16 2016 +0000
@@ -0,0 +1,880 @@
+/*******************************************************************************
+ * Copyright (C) 2016 Maxim Integrated Products, Inc., All Rights Reserved.
+ *
+ * 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 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 MAXIM INTEGRATED 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.
+ *
+ * Except as contained in this notice, the name of Maxim Integrated
+ * Products, Inc. shall not be used except as stated in the Maxim Integrated
+ * Products, Inc. Branding Policy.
+ *
+ * The mere transfer of this software does not imply any licenses
+ * of trade secrets, proprietary technology, copyrights, patents,
+ * trademarks, maskwork rights, or any other form of intellectual
+ * property whatsoever. Maxim Integrated Products, Inc. retains all
+ * ownership rights.
+ *
+ * $Date: 2016-06-01 08:51:23 -0500 (Wed, 01 Jun 2016) $
+ * $Revision: 23131 $
+ *
+ ******************************************************************************/
+
+/**
+ * @file i2cm.c
+ * @brief I2C Master driver source.
+ */
+
+/***** Includes *****/
+#include <string.h>
+#include <math.h>
+#include "mxc_assert.h"
+#include "mxc_lock.h"
+#include "mxc_errors.h"
+#include "mxc_sys.h"
+#include "i2cm.h"
+
+/***** Definitions *****/
+
+#ifndef MXC_I2CM_TX_TIMEOUT
+#define MXC_I2CM_TX_TIMEOUT 0x5000
+#endif
+
+#ifndef MXC_I2CM_RX_TIMEOUT
+#define MXC_I2CM_RX_TIMEOUT 0x5000
+#endif
+
+#define I2CM_READ_BIT 0x0001
+#define I2CM_FIFO_DEPTH_3Q ((3 * MXC_I2CM_FIFO_DEPTH) / 4)
+#define I2CM_FIFO_DEPTH_2Q (MXC_I2CM_FIFO_DEPTH / 2)
+
+/***** Globals *****/
+
+// Saves the state of the non-blocking requests
+typedef enum {
+ I2CM_STATE_READING = 0,
+ I2CM_STATE_WRITING = 1
+} i2cm_state_t;
+
+typedef struct {
+ i2cm_req_t *req;
+ i2cm_state_t state;
+} i2cm_req_state_t;
+static i2cm_req_state_t states[MXC_CFG_I2CM_INSTANCES];
+
+/***** Functions *****/
+
+//static void I2CM_Recover(mxc_i2cm_regs_t *i2cm);
+//static int I2CM_WriteTxFifo(mxc_i2cm_regs_t *regs, mxc_i2cm_fifo_regs_t *fifo, const uint16_t data);
+//static int I2CM_TxInProgress(mxc_i2cm_regs_t *i2cm);
+static void I2CM_FreeCallback(int i2cm_num, int error);
+//static int I2CM_Tx(mxc_i2cm_regs_t *i2cm, mxc_i2cm_fifo_regs_t *fifo, uint8_t addr,
+// const uint8_t *data, uint32_t len, uint8_t stop);
+
+//static int I2CM_Rx(mxc_i2cm_regs_t *i2cm, mxc_i2cm_fifo_regs_t *fifo, uint8_t addr,
+// uint8_t *data, uint32_t len);
+
+static int I2CM_CmdHandler(mxc_i2cm_regs_t *i2cm, mxc_i2cm_fifo_regs_t *fifo, i2cm_req_t *req);
+static int I2CM_ReadHandler(mxc_i2cm_regs_t *i2cm, i2cm_req_t *req, int i2cm_num);
+static int I2CM_WriteHandler(mxc_i2cm_regs_t *i2cm, i2cm_req_t *req, int i2cm_num);
+
+/******************************************************************************/
+int I2CM_Init(mxc_i2cm_regs_t *i2cm, const sys_cfg_i2cm_t *sys_cfg, i2cm_speed_t speed)
+{
+ int err;
+
+ // Check the base pointer
+ MXC_ASSERT(MXC_I2CM_GET_IDX(i2cm) >= 0);
+
+ // Set system level configurations
+ if ((err = SYS_I2CM_Init(i2cm, sys_cfg)) != E_NO_ERROR) {
+ return err;
+ }
+
+ I2CM_SetFrequency(i2cm,speed);
+
+ // Reset module
+ i2cm->ctrl = MXC_F_I2CM_CTRL_MSTR_RESET_EN;
+ i2cm->ctrl = 0;
+
+ // Set timeout to 255 ms and turn on the auto-stop option
+ i2cm->timeout = (MXC_F_I2CM_TIMEOUT_TX_TIMEOUT | MXC_F_I2CM_TIMEOUT_AUTO_STOP_EN);
+
+ // Enable tx_fifo and rx_fifo
+ i2cm->ctrl |= (MXC_F_I2CM_CTRL_TX_FIFO_EN | MXC_F_I2CM_CTRL_RX_FIFO_EN);
+
+ return E_NO_ERROR;
+}
+
+/******************************************************************************/
+int I2CM_Shutdown(mxc_i2cm_regs_t *i2cm)
+{
+ int i2cm_num, err;
+
+ // Check the base pointer
+ i2cm_num = MXC_I2CM_GET_IDX(i2cm);
+ MXC_ASSERT(i2cm_num >= 0);
+
+ // Disable and clear interrupts
+ i2cm->inten = 0;
+ i2cm->intfl = i2cm->intfl;
+
+ // Call all of the pending callbacks for this I2CM
+ if(states[i2cm_num].req != NULL) {
+ I2CM_Recover(i2cm);
+ I2CM_FreeCallback(i2cm_num, E_SHUTDOWN);
+ }
+
+ // Clears system level configurations
+ if ((err = SYS_I2CM_Shutdown(i2cm)) != E_NO_ERROR) {
+ return err;
+ }
+
+ return E_NO_ERROR;
+}
+
+
+/******************************************************************************/
+int I2CM_Read(mxc_i2cm_regs_t *i2cm, uint8_t addr, const uint8_t *cmd_data,
+ uint32_t cmd_len, uint8_t* data, uint32_t len)
+{
+ int i2cm_num;
+ int error = E_NO_ERROR;
+ int retval = E_NO_ERROR;
+ mxc_i2cm_fifo_regs_t *fifo;
+
+ if(data == NULL) {
+ return E_NULL_PTR;
+ }
+
+ // Make sure the I2CM has been initialized
+ if(i2cm->ctrl == 0) {
+ return E_UNINITIALIZED;
+ }
+
+ if(!(len > 0)) {
+ return E_NO_ERROR;
+ }
+
+ // Lock this I2CM
+ i2cm_num = MXC_I2CM_GET_IDX(i2cm);
+ while(mxc_get_lock((uint32_t*)&states[i2cm_num].req,1) != E_NO_ERROR) {}
+
+ // Get the FIFO pointer for this I2CM
+ fifo = MXC_I2CM_GET_FIFO(i2cm_num);
+
+ // Disable and clear the interrupts
+ i2cm->inten = 0;
+ i2cm->intfl = i2cm->intfl;
+
+ // Transmit the command if there is command data and length
+ if((cmd_data != NULL) && (cmd_len > 0)) {
+ retval = I2CM_Tx(i2cm, fifo, addr, cmd_data, cmd_len, 0);
+ }
+
+ // Read data from the slave if we don't have any errors
+ if(retval == E_NO_ERROR) {
+ retval = I2CM_Rx(i2cm, fifo, addr, data, len);
+ }
+
+ // Wait for the transaction to complete
+ if((error = I2CM_TxInProgress(i2cm)) != E_NO_ERROR) {
+ retval = error;
+ }
+
+ // Unlock this I2CM
+ mxc_free_lock((uint32_t*)&states[i2cm_num].req);
+
+ if(retval != E_NO_ERROR) {
+ return retval;
+ }
+
+ return len;
+}
+
+/******************************************************************************/
+int I2CM_Write(mxc_i2cm_regs_t *i2cm, uint8_t addr, const uint8_t *cmd_data,
+ uint32_t cmd_len, uint8_t* data, uint32_t len)
+{
+ int i2cm_num;
+ int error = E_NO_ERROR;
+ int retval = E_NO_ERROR;
+ mxc_i2cm_fifo_regs_t *fifo;
+
+ if(data == NULL) {
+ return E_NULL_PTR;
+ }
+
+ // Make sure the I2CM has been initialized
+ if(i2cm->ctrl == 0) {
+ return E_UNINITIALIZED;
+ }
+
+ if(!(len > 0)) {
+ return E_NO_ERROR;
+ }
+
+ // Lock this I2CM
+ i2cm_num = MXC_I2CM_GET_IDX(i2cm);
+ while(mxc_get_lock((uint32_t*)&states[i2cm_num].req,1) != E_NO_ERROR) {}
+
+ // Get the FIFO pointer for this I2CM
+ fifo = MXC_I2CM_GET_FIFO(i2cm_num);
+
+ // Disable and clear the interrupts
+ i2cm->inten = 0;
+ i2cm->intfl = i2cm->intfl;
+
+ // Transmit the command if there is command data and length, don't send stop bit
+ if((cmd_data != NULL) && (cmd_len > 0)) {
+ retval = I2CM_Tx(i2cm, fifo, addr, cmd_data, cmd_len, 0);
+ }
+
+ // Write data to the slave, send the stop bit
+ if(retval == E_NO_ERROR) {
+ retval = I2CM_Tx(i2cm, fifo, addr, data, len, 1);
+ }
+
+ // Wait for the transaction to complete
+ if((error = I2CM_TxInProgress(i2cm)) != E_NO_ERROR) {
+ retval = error;
+ }
+
+ // Unlock this I2CM
+ mxc_free_lock((uint32_t*)&states[i2cm_num].req);
+
+ if(retval != E_NO_ERROR) {
+ return retval;
+ }
+
+ return len;
+}
+
+/******************************************************************************/
+int I2CM_ReadAsync(mxc_i2cm_regs_t *i2cm, i2cm_req_t *req)
+{
+ int i2cm_num, error;
+
+ if(req->data == NULL) {
+ return E_NULL_PTR;
+ }
+
+ // Make sure the I2CM has been initialized
+ if(i2cm->ctrl == 0) {
+ return E_UNINITIALIZED;
+ }
+
+ if(!(req->data_len > 0)) {
+ return E_NO_ERROR;
+ }
+
+ i2cm_num = MXC_I2CM_GET_IDX(i2cm);
+
+ // Attempt to register this request
+ if(mxc_get_lock((uint32_t*)&states[i2cm_num].req, (uint32_t)req) != E_NO_ERROR) {
+ return E_BUSY;
+ }
+
+ states[i2cm_num].state = I2CM_STATE_READING;
+
+ // Clear the number of bytes counter
+ req->cmd_num = 0;
+ req->data_num = 0;
+
+ // Disable and clear the interrupts
+ i2cm->inten = 0;
+ i2cm->intfl = i2cm->intfl;
+
+ // Start the read
+ if((error = I2CM_ReadHandler(i2cm, req, i2cm_num)) != E_NO_ERROR) {
+ I2CM_Recover(i2cm);
+ I2CM_FreeCallback(i2cm_num, error);
+ return error;
+ }
+
+ return E_NO_ERROR;
+}
+
+/******************************************************************************/
+int I2CM_WriteAsync(mxc_i2cm_regs_t *i2cm, i2cm_req_t *req)
+{
+ int i2cm_num, error;
+
+ if(req->data == NULL) {
+ return E_NULL_PTR;
+ }
+
+ // Make sure the I2CM has been initialized
+ if(i2cm->ctrl == 0) {
+ return E_UNINITIALIZED;
+ }
+
+ if(!(req->data_len > 0)) {
+ return E_NO_ERROR;
+ }
+
+ i2cm_num = MXC_I2CM_GET_IDX(i2cm);
+
+ // Attempt to register this request
+ if(mxc_get_lock((uint32_t*)&states[i2cm_num].req, (uint32_t)req) != E_NO_ERROR) {
+ return E_BUSY;
+ }
+
+ states[i2cm_num].state = I2CM_STATE_WRITING;
+
+ // Clear the number of bytes counter
+ req->cmd_num = 0;
+ req->data_num = 0;
+
+ // Disable and clear the interrupts
+ i2cm->inten = 0;
+ i2cm->intfl = i2cm->intfl;
+
+ // Start the Write
+ if((error = I2CM_WriteHandler(i2cm, req, i2cm_num)) != E_NO_ERROR) {
+ I2CM_Recover(i2cm);
+ I2CM_FreeCallback(i2cm_num, error);
+ return error;
+ }
+
+ return E_NO_ERROR;
+}
+
+/******************************************************************************/
+int I2CM_AbortAsync(i2cm_req_t *req)
+{
+ int i2cm_num;
+ mxc_i2cm_regs_t *i2cm;
+
+ // Find the request, set to NULL
+ for(i2cm_num = 0; i2cm_num < MXC_CFG_I2CM_INSTANCES; i2cm_num++) {
+ if(req == states[i2cm_num].req) {
+
+ i2cm = MXC_I2CM_GET_I2CM(i2cm_num);
+ I2CM_Recover(i2cm);
+ I2CM_FreeCallback(i2cm_num, E_ABORT);
+
+ return E_NO_ERROR;
+ }
+ }
+
+ return E_BAD_PARAM;
+}
+
+/******************************************************************************/
+void I2CM_Handler(mxc_i2cm_regs_t *i2cm)
+{
+ uint32_t intfl;
+ int i2cm_num, error;
+
+ // Save and clear the interrupts
+ intfl = i2cm->intfl;
+ i2cm->intfl = intfl;
+
+ // Mask the disabled interrupts
+ intfl &= i2cm->inten;
+
+ i2cm_num = MXC_I2CM_GET_IDX(i2cm);
+
+ // Check for errors
+ if ((intfl & MXC_F_I2CM_INTFL_TX_NACKED) || (intfl & MXC_F_I2CM_INTFL_TX_LOST_ARBITR)) {
+ I2CM_Recover(i2cm);
+ I2CM_FreeCallback(i2cm_num, E_COMM_ERR);
+ return;
+ }
+
+ if(intfl & MXC_F_I2CM_INTFL_TX_TIMEOUT) {
+ I2CM_Recover(i2cm);
+ I2CM_FreeCallback(i2cm_num, E_TIME_OUT);
+ return;
+ }
+
+ // Read or write
+ if(states[i2cm_num].state == I2CM_STATE_READING) {
+ if((error = I2CM_ReadHandler(i2cm, states[i2cm_num].req, i2cm_num)) != E_NO_ERROR) {
+ I2CM_Recover(i2cm);
+ I2CM_FreeCallback(i2cm_num, error);
+ return;
+ }
+
+ } else if(states[i2cm_num].state == I2CM_STATE_WRITING) {
+ if((error = I2CM_WriteHandler(i2cm, states[i2cm_num].req, i2cm_num)) != E_NO_ERROR) {
+ I2CM_Recover(i2cm);
+ I2CM_FreeCallback(i2cm_num, error);
+ return;
+ }
+ }
+
+ // Done with the transaction
+ if(intfl & MXC_F_I2CM_INTFL_TX_DONE) {
+ I2CM_Recover(i2cm);
+ I2CM_FreeCallback(i2cm_num, E_NO_ERROR);
+ }
+
+}
+
+/******************************************************************************/
+int I2CM_Busy(mxc_i2cm_regs_t *i2cm)
+{
+ // Check to see if there are any ongoing transactions
+ if((states[MXC_I2CM_GET_IDX(i2cm)].req == NULL) &&
+ !(i2cm->trans & MXC_F_I2CM_TRANS_TX_IN_PROGRESS)) {
+
+ return E_NO_ERROR;
+ }
+
+ return E_BUSY;
+}
+
+/******************************************************************************/
+int I2CM_PrepForSleep(mxc_i2cm_regs_t *i2cm)
+{
+ if(I2CM_Busy(i2cm) != E_NO_ERROR) {
+ return E_BUSY;
+ }
+
+ // Disable interrupts
+ i2cm->inten = 0;
+ return E_NO_ERROR;
+}
+
+/******************************************************************************/
+int I2CM_BusCheck(mxc_i2cm_regs_t *i2cm)
+{
+ // If SCL is low, we don't have the bus
+ if(!(i2cm->bb & MXC_F_I2CM_BB_BB_SCL_IN_VAL)) {
+ return E_BUSY;
+ }
+
+ // If SDA is low, we don't have the bus
+ if(!(i2cm->bb & MXC_F_I2CM_BB_BB_SDA_IN_VAL)) {
+ return E_BUSY;
+ }
+
+ return E_NO_ERROR;
+}
+
+/******************************************************************************/
+static void I2CM_FreeCallback(int i2cm_num, int error)
+{
+ // Save the request
+ i2cm_req_t *temp_req = states[i2cm_num].req;
+
+ // Unlock this UART to write
+ mxc_free_lock((uint32_t*)&states[i2cm_num].req);
+
+ // Callback if not NULL
+ if(temp_req->callback != NULL) {
+ temp_req->callback(temp_req, error);
+ }
+}
+
+/******************************************************************************/
+void I2CM_Recover(mxc_i2cm_regs_t *i2cm)
+{
+ // Disable and clear interrupts
+ i2cm->inten = 0;
+ i2cm->intfl = i2cm->intfl;
+ i2cm->ctrl = MXC_F_I2CM_CTRL_MSTR_RESET_EN;
+ i2cm->ctrl = MXC_F_I2CM_CTRL_TX_FIFO_EN | MXC_F_I2CM_CTRL_RX_FIFO_EN;
+}
+
+/******************************************************************************/
+int I2CM_WriteTxFifo(mxc_i2cm_regs_t *i2cm, mxc_i2cm_fifo_regs_t *fifo, const uint16_t data)
+{
+ int32_t timeout = MXC_I2CM_TX_TIMEOUT;
+
+ // Read the TX FIFO to determine if it's full
+ do {
+
+ // Wait for the TX FIFO to have room and check for errors
+ if (i2cm->intfl & (MXC_F_I2CM_INTFL_TX_NACKED |
+ MXC_F_I2CM_INTFL_TX_LOST_ARBITR)) {
+
+ return E_COMM_ERR;
+ }
+
+ if((i2cm->intfl & MXC_F_I2CM_INTFL_TX_TIMEOUT) || !timeout--) {
+ return E_TIME_OUT;
+ }
+
+ } while (fifo->tx);
+
+ fifo->tx = data;
+
+ return E_NO_ERROR;
+}
+
+/******************************************************************************/
+int I2CM_TxInProgress(mxc_i2cm_regs_t *i2cm)
+{
+ int32_t timeout = MXC_I2CM_TX_TIMEOUT;
+
+ while ((i2cm->trans & MXC_F_I2CM_TRANS_TX_IN_PROGRESS) && --timeout);
+
+ if (i2cm->intfl & (MXC_F_I2CM_INTFL_TX_NACKED |
+ MXC_F_I2CM_INTFL_TX_LOST_ARBITR)) {
+
+ I2CM_Recover(i2cm);
+ return E_COMM_ERR;
+ }
+
+ if((i2cm->intfl & MXC_F_I2CM_INTFL_TX_TIMEOUT) && !timeout--) {
+ I2CM_Recover(i2cm);
+ return E_TIME_OUT;
+ }
+
+ return E_NO_ERROR;
+}
+
+/******************************************************************************/
+int I2CM_Tx(mxc_i2cm_regs_t *i2cm, mxc_i2cm_fifo_regs_t *fifo, uint8_t addr,
+ const uint8_t *data, uint32_t len, uint8_t stop)
+{
+ uint32_t i;
+ int error;
+
+ // Write the address to the TXFIFO
+ if((error = I2CM_WriteTxFifo(i2cm, fifo, (MXC_S_I2CM_TRANS_TAG_START | (addr << 1)))) != E_NO_ERROR) {
+ return error;
+ }
+
+ // Start the transaction if it is not currently ongoing
+ if (!(i2cm->trans & MXC_F_I2CM_TRANS_TX_IN_PROGRESS)) {
+ i2cm->trans |= MXC_F_I2CM_TRANS_TX_START;
+ }
+
+ // Fill the FIFO
+ for (i = 0; i < len; i++) {
+ if((error = I2CM_WriteTxFifo(i2cm, fifo, (MXC_S_I2CM_TRANS_TAG_TXDATA_ACK | data[i]))) != E_NO_ERROR) {
+ return error;
+ }
+ }
+
+ // Send the stop condition
+ if(stop) {
+ if ((error = I2CM_WriteTxFifo(i2cm, fifo, MXC_S_I2CM_TRANS_TAG_STOP)) != E_NO_ERROR) {
+ return error;
+ }
+ }
+
+ return E_NO_ERROR;
+}
+
+/******************************************************************************/
+int I2CM_Rx(mxc_i2cm_regs_t *i2cm, mxc_i2cm_fifo_regs_t *fifo, uint8_t addr,
+ uint8_t *data, uint32_t len)
+{
+ uint32_t i = len;
+ int32_t timeout;
+ uint16_t temp;
+ int error;
+
+ // Write the address to the TXFIFO
+ if((error = I2CM_WriteTxFifo(i2cm, fifo, (MXC_S_I2CM_TRANS_TAG_START |
+ (addr << 1) | I2CM_READ_BIT))) != E_NO_ERROR) {
+
+ return error;
+ }
+
+ // Write to the TXFIFO the number of bytes we want to read
+ while(i > 256) {
+ if((error = I2CM_WriteTxFifo(i2cm, fifo, (MXC_S_I2CM_TRANS_TAG_RXDATA_COUNT | 255))) != E_NO_ERROR) {
+ return error;
+ }
+
+ i -= 256;
+ }
+
+ if(i > 1) {
+ if((error = I2CM_WriteTxFifo(i2cm, fifo, (MXC_S_I2CM_TRANS_TAG_RXDATA_COUNT | (i-2)))) != E_NO_ERROR) {
+ return error;
+ }
+ }
+
+ // Start the transaction if it is not currently ongoing
+ if (!(i2cm->trans & MXC_F_I2CM_TRANS_TX_IN_PROGRESS)) {
+ i2cm->trans |= MXC_F_I2CM_TRANS_TX_START;
+ }
+
+
+ // NACK the last read byte
+ if((error = I2CM_WriteTxFifo(i2cm, fifo, (MXC_S_I2CM_TRANS_TAG_RXDATA_NACK))) != E_NO_ERROR) {
+ return error;
+ }
+
+ // Send the stop condition
+ if ((error = I2CM_WriteTxFifo(i2cm, fifo, MXC_S_I2CM_TRANS_TAG_STOP)) != E_NO_ERROR) {
+ return error;
+ }
+
+ // Get the data from the RX FIFO
+ i = 0;
+ while (i < len) {
+
+ // Wait for there to be data in the RX FIFO
+ timeout = MXC_I2CM_RX_TIMEOUT;
+ while (!(i2cm->intfl & MXC_F_I2CM_INTFL_RX_FIFO_NOT_EMPTY) &&
+ ((i2cm->bb & MXC_F_I2CM_BB_RX_FIFO_CNT) == 0)) {
+
+ if((timeout-- < 0) || (i2cm->trans & MXC_F_I2CM_TRANS_TX_TIMEOUT)) {
+ return E_TIME_OUT;
+ }
+
+ if (i2cm->trans & (MXC_F_I2CM_TRANS_TX_LOST_ARBITR | MXC_F_I2CM_TRANS_TX_NACKED)) {
+ return E_COMM_ERR;
+ }
+ }
+ i2cm->intfl = MXC_F_I2CM_INTFL_RX_FIFO_NOT_EMPTY;
+
+ // Save the data from the RX FIFO
+ temp = fifo->rx;
+ if (temp & MXC_S_I2CM_RSTLS_TAG_EMPTY) {
+ continue;
+ }
+ data[i++] = (uint8_t)temp;
+ }
+
+ return E_NO_ERROR;
+}
+
+/******************************************************************************/
+static int I2CM_CmdHandler(mxc_i2cm_regs_t *i2cm, mxc_i2cm_fifo_regs_t *fifo, i2cm_req_t *req)
+{
+ int error;
+
+ // Start of the command
+ if(req->cmd_num == 0) {
+
+ // Write the address to the TXFIFO
+ if((error = I2CM_WriteTxFifo(i2cm, fifo, (MXC_S_I2CM_TRANS_TAG_START | (req->addr << 1)))) != E_NO_ERROR) {
+ return error;
+ }
+
+ // Start the transaction if it is not currently ongoing
+ if (!(i2cm->trans & MXC_F_I2CM_TRANS_TX_IN_PROGRESS)) {
+ i2cm->trans |= MXC_F_I2CM_TRANS_TX_START;
+ }
+ }
+
+ // Write to the FIFO until it is full or we run out of command bytes
+ while((req->cmd_num < req->cmd_len) && (!fifo->tx)) {
+ fifo->tx = MXC_S_I2CM_TRANS_TAG_TXDATA_ACK | req->cmd_data[req->cmd_num++];
+ }
+
+ return E_NO_ERROR;
+}
+
+/******************************************************************************/
+static int I2CM_ReadHandler(mxc_i2cm_regs_t *i2cm, i2cm_req_t *req, int i2cm_num)
+{
+ int error, cmd_remain, data_remain;
+ uint16_t data;
+ uint32_t temp_len, inten;
+ mxc_i2cm_fifo_regs_t *fifo;
+
+ // Get the FIFO pointer for this I2CM
+ fifo = MXC_I2CM_GET_FIFO(i2cm_num);
+
+ cmd_remain = req->cmd_len - req->cmd_num;
+ data_remain = req->data_len - req->data_num;
+
+ // Process the command portion
+ if((cmd_remain) && (req->cmd_data != NULL)) {
+ if((error = I2CM_CmdHandler(i2cm, fifo, req)) != E_NO_ERROR) {
+ return error;
+ }
+
+ cmd_remain = req->cmd_len - req->cmd_num;
+ }
+
+ // Process the data portion
+ if((cmd_remain == 0) && (data_remain)) {
+
+ // Save the data from the RXFIFO
+ data = fifo->rx;
+ while((req->data_num < req->data_len) && !(data & MXC_S_I2CM_RSTLS_TAG_EMPTY)) {
+ req->data[req->data_num++] = data;
+ data = fifo->rx;
+ }
+
+ // Start of the data portion
+ if(req->data_num == 0) {
+
+ temp_len = req->data_len;
+
+ // Write the address to the TXFIFO
+ if((error = I2CM_WriteTxFifo(i2cm, fifo, (MXC_S_I2CM_TRANS_TAG_START |
+ (req->addr << 1) | I2CM_READ_BIT))) != E_NO_ERROR) {
+
+ return error;
+ }
+
+ // Write to the TXFIFO the number of bytes we want to read
+ while(temp_len > 256) {
+ if((error = I2CM_WriteTxFifo(i2cm, fifo, (MXC_S_I2CM_TRANS_TAG_RXDATA_COUNT | 255))) != E_NO_ERROR) {
+ return error;
+ }
+
+ temp_len -= 256;
+ }
+
+ if(temp_len > 1) {
+ if((error = I2CM_WriteTxFifo(i2cm, fifo, (MXC_S_I2CM_TRANS_TAG_RXDATA_COUNT | (temp_len-2)))) != E_NO_ERROR) {
+ return error;
+ }
+ }
+
+ // Start the transaction if it is not currently ongoing
+ if (!(i2cm->trans & MXC_F_I2CM_TRANS_TX_IN_PROGRESS)) {
+ i2cm->trans |= MXC_F_I2CM_TRANS_TX_START;
+ }
+
+ // NACK the last read byte
+ if((error = I2CM_WriteTxFifo(i2cm, fifo, (MXC_S_I2CM_TRANS_TAG_RXDATA_NACK))) != E_NO_ERROR) {
+ return error;
+ }
+
+ // Send the stop condition
+ if ((error = I2CM_WriteTxFifo(i2cm, fifo, MXC_S_I2CM_TRANS_TAG_STOP)) != E_NO_ERROR) {
+ return error;
+ }
+ }
+ }
+
+ // Enable the required interrupts
+ inten = MXC_F_I2CM_INTEN_TX_DONE | MXC_F_I2CM_INTEN_TX_NACKED |
+ MXC_F_I2CM_INTEN_TX_LOST_ARBITR | MXC_F_I2CM_INTEN_TX_TIMEOUT;
+
+ if (cmd_remain) {
+ inten |= (MXC_F_I2CM_INTEN_TX_FIFO_EMPTY | MXC_F_I2CM_INTEN_TX_FIFO_3Q_EMPTY);
+ }
+
+ data_remain = req->data_len - req->data_num;
+ if (data_remain > I2CM_FIFO_DEPTH_3Q) {
+ inten |= MXC_F_I2CM_INTEN_RX_FIFO_3Q_FULL;
+
+ } else if (data_remain > I2CM_FIFO_DEPTH_2Q) {
+ inten |= MXC_F_I2CM_INTEN_RX_FIFO_2Q_FULL;
+
+ } else if (data_remain > 0) {
+ inten |= MXC_F_I2CM_INTEN_RX_FIFO_NOT_EMPTY;
+ }
+
+ i2cm->inten = inten;
+
+ return E_NO_ERROR;
+}
+
+/******************************************************************************/
+static int I2CM_WriteHandler(mxc_i2cm_regs_t *i2cm, i2cm_req_t *req, int i2cm_num)
+{
+ int error, cmd_remain, data_remain;
+ uint32_t inten;
+ mxc_i2cm_fifo_regs_t *fifo;
+
+ // Get the FIFO pointer for this I2CM
+ fifo = MXC_I2CM_GET_FIFO(i2cm_num);
+
+ cmd_remain = req->cmd_len - req->cmd_num;
+ data_remain = req->data_len - req->data_num;
+
+ // Process the command portion
+ if((cmd_remain) && (req->cmd_data != NULL)) {
+ if((error = I2CM_CmdHandler(i2cm, fifo, req)) != E_NO_ERROR) {
+ return error;
+ }
+
+ cmd_remain = req->cmd_len - req->cmd_num;
+ }
+
+ // Process the data portion
+ if((cmd_remain == 0) && (data_remain)) {
+
+ // Start of the data portion
+ if(req->data_num == 0) {
+
+ // Write the address to the TXFIFO
+ if((error = I2CM_WriteTxFifo(i2cm, fifo, (MXC_S_I2CM_TRANS_TAG_START |
+ (req->addr << 1)))) != E_NO_ERROR) {
+
+ return error;
+ }
+
+ // Start the transaction if it is not currently ongoing
+ if (!(i2cm->trans & MXC_F_I2CM_TRANS_TX_IN_PROGRESS)) {
+ i2cm->trans |= MXC_F_I2CM_TRANS_TX_START;
+ }
+ }
+
+ // Write bytes to the FIFO until it's full or we run out of bytes
+ while(req->data_num < req->data_len) {
+ fifo->tx = MXC_S_I2CM_TRANS_TAG_TXDATA_ACK | req->data[req->data_num++];
+ }
+
+ // Send the stop condition
+ if ((error = I2CM_WriteTxFifo(i2cm, fifo, MXC_S_I2CM_TRANS_TAG_STOP)) != E_NO_ERROR) {
+ return error;
+ }
+ }
+
+ // Enable the required interrupts
+ data_remain = req->data_len - req->data_num;
+ inten = MXC_F_I2CM_INTEN_TX_DONE | MXC_F_I2CM_INTEN_TX_NACKED |
+ MXC_F_I2CM_INTEN_TX_LOST_ARBITR | MXC_F_I2CM_INTEN_TX_TIMEOUT;
+
+ if(data_remain || cmd_remain) {
+ inten |= (MXC_F_I2CM_INTEN_TX_FIFO_EMPTY | MXC_F_I2CM_INTEN_TX_FIFO_3Q_EMPTY);
+ }
+ i2cm->inten = inten;
+
+ return E_NO_ERROR;
+}
+
+int I2CM_SetFrequency(mxc_i2cm_regs_t *i2cm, int speed)
+{
+ // Speed converted into Khz
+ float i2cSpeed = speed / 1000.0f;
+ //get clk speed into MHz
+ int sClk = SYS_I2CM_GetFreq(i2cm) / 1000000;
+ // duty cycle of .67
+ float dc = 2.0f / 3.0f;
+ //Hold Time
+ float hold = (100.0f / i2cSpeed);
+ int riseTime;
+ //max rise time based on speed according to the I2C specs
+ if (i2cSpeed <= 100) {
+ riseTime = 1000;
+ } else if (i2cSpeed <= 400) {
+ riseTime = 300;
+ } else if (i2cSpeed <= 1000) {
+ riseTime = 120;
+ } else {
+ return E_NOT_SUPPORTED;
+ }
+ // Clock cycles to delay
+ int latency = 4;
+ int filtDev, sclHi, sclLow;
+ filtDev = (hold * sClk) / 2;
+ sclHi = (((dc * sClk * 1000.0f / i2cSpeed) - (((2.5f * filtDev) + (riseTime / 1000.0f * sClk) + latency) * (1.0f + dc))) / (1.0f + dc));
+ sclLow = ((sClk * 1000.0f / i2cSpeed) - (2.5f * filtDev) - (riseTime / 1000.0f * sClk) - latency - sclHi);
+
+ i2cm->fs_clk_div = ((filtDev << MXC_F_I2CM_FS_CLK_DIV_FS_FILTER_CLK_DIV_POS) |
+ (sclHi << MXC_F_I2CM_FS_CLK_DIV_FS_SCL_HI_CNT_POS) |
+ (sclLow << MXC_F_I2CM_FS_CLK_DIV_FS_SCL_LO_CNT_POS));
+ return E_NO_ERROR;
+}
\ No newline at end of file