mbed-os/targets/TARGET_Maxim/TARGET_MAX32620C/i2c_api.c

233 lines
7.1 KiB
C

/*******************************************************************************
* 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.
*******************************************************************************
*/
#include "mbed_assert.h"
#include "i2c_api.h"
#if DEVICE_I2C
#include "i2cm_regs.h"
#include "i2cm.h"
#include "pinmap.h"
#include "PeripheralPins.h"
#ifndef MXC_I2CM_RX_TIMEOUT
#define MXC_I2CM_RX_TIMEOUT 0x5000
#endif
#define MBED_NAK 0
#define MBED_ACK 1
#define MBED_TIMEOUT 2
//******************************************************************************
void i2c_init(i2c_t *obj, PinName sda, PinName scl)
{
// SDA and SCL must map to same peripheral instance
I2CName i2c_sda = (I2CName)pinmap_peripheral(sda, PinMap_I2C_SDA);
I2CName i2c_scl = (I2CName)pinmap_peripheral(scl, PinMap_I2C_SCL);
mxc_i2cm_regs_t *i2c = (mxc_i2cm_regs_t*)pinmap_merge(i2c_sda, i2c_scl);
MBED_ASSERT((int)i2c != NC);
obj->i2c = i2c;
obj->fifo = MXC_I2CM_GET_FIFO(MXC_I2CM_GET_IDX(i2c));
obj->start_pending = 0;
// Merge pin function requests for use with CMSIS init func
ioman_req_t io_req;
pin_function_t *pin_func;
pin_func = (pin_function_t *)pinmap_find_function(sda, PinMap_I2C_SDA);
io_req.value = pin_func->req_val;
pin_func = (pin_function_t *)pinmap_find_function(scl, PinMap_I2C_SCL);
io_req.value |= pin_func->req_val;
obj->sys_cfg.io_cfg.req_reg = pin_func->reg_req;
obj->sys_cfg.io_cfg.ack_reg = pin_func->reg_ack;
obj->sys_cfg.io_cfg.req_val = io_req;
obj->sys_cfg.clk_scale = CLKMAN_SCALE_DIV_1;
I2CM_Init(obj->i2c, &obj->sys_cfg, I2CM_SPEED_100KHZ);
}
//******************************************************************************
void i2c_frequency(i2c_t *obj, int hz)
{
I2CM_Init(obj->i2c, &obj->sys_cfg, (i2cm_speed_t)hz);
}
//******************************************************************************
int i2c_start(i2c_t *obj)
{
obj->start_pending = 1;
return 0;
}
//******************************************************************************
int i2c_stop(i2c_t *obj)
{
obj->start_pending = 0;
I2CM_WriteTxFifo(obj->i2c, obj->fifo, MXC_S_I2CM_TRANS_TAG_STOP);
I2CM_TxInProgress(obj->i2c);
return 0;
}
//******************************************************************************
int i2c_read(i2c_t *obj, int address, char *data, int length, int stop)
{
return I2CM_Read(obj->i2c, address >> 1, NULL, 0, (uint8_t *)data, length, stop);
}
//******************************************************************************
int i2c_write(i2c_t *obj, int address, const char *data, int length, int stop)
{
mxc_i2cm_regs_t *i2cm = obj->i2c;
mxc_i2cm_fifo_regs_t *fifo = obj->fifo;
if (stop) {
return I2CM_Write(i2cm, address >> 1, NULL, 0, (uint8_t *)data, length);
}
i2cm->inten = 0;
i2cm->intfl = i2cm->intfl;
if (I2CM_Tx(i2cm, fifo, address >> 1, (uint8_t *)data, length, 0) == E_NO_ERROR) {
return length;
} else {
return -1;
}
}
//******************************************************************************
void i2c_reset(i2c_t *obj)
{
I2CM_Recover(obj->i2c);
}
//******************************************************************************
int i2c_byte_read(i2c_t *obj, int last)
{
mxc_i2cm_regs_t *i2cm = obj->i2c;
mxc_i2cm_fifo_regs_t *fifo = obj->fifo;
int tmp;
// 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;
}
if (last) {
// NACK the last read byte
if (I2CM_WriteTxFifo(i2cm, fifo, MXC_S_I2CM_TRANS_TAG_RXDATA_NACK) != E_NO_ERROR) {
goto byte_read_err;
}
} else {
if (I2CM_WriteTxFifo(i2cm, fifo, MXC_S_I2CM_TRANS_TAG_RXDATA_COUNT) != E_NO_ERROR) {
goto byte_read_err;
}
}
do {
// Wait for data in RX FIFO
int 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)) {
goto byte_read_err;
}
if (i2cm->trans & (MXC_F_I2CM_TRANS_TX_LOST_ARBITR | MXC_F_I2CM_TRANS_TX_NACKED)) {
goto byte_read_err;
}
}
i2cm->intfl = MXC_F_I2CM_INTFL_RX_FIFO_NOT_EMPTY;
} while ((tmp = fifo->rx) & MXC_S_I2CM_RSTLS_TAG_EMPTY);
return (uint8_t)tmp;
byte_read_err:
i2c_reset(obj);
return -1;
}
//******************************************************************************
int i2c_byte_write(i2c_t *obj, int data)
{
mxc_i2cm_regs_t *i2cm = obj->i2c;
mxc_i2cm_fifo_regs_t *fifo = obj->fifo;
int result;
if (obj->start_pending) {
obj->start_pending = 0;
data |= MXC_S_I2CM_TRANS_TAG_START;
} else {
data |= MXC_S_I2CM_TRANS_TAG_TXDATA_ACK;
}
if ((result = I2CM_WriteTxFifo(i2cm, fifo, data)) != E_NO_ERROR) {
i2c_reset(obj);
if (result == E_COMM_ERR) {
return MBED_NAK;
}
return MBED_TIMEOUT;
}
// 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;
}
return MBED_ACK;
}
const PinMap *i2c_master_sda_pinmap()
{
return PinMap_I2C_SDA;
}
const PinMap *i2c_master_scl_pinmap()
{
return PinMap_I2C_SCL;
}
const PinMap *i2c_slave_sda_pinmap()
{
return PinMap_I2C_SDA;
}
const PinMap *i2c_slave_scl_pinmap()
{
return PinMap_I2C_SCL;
}
#endif // #if DEVICE_I2C