i2c.h

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/******************************************************************************
 *  Filename:       i2c.h
 *
 *  Description:    Prototypes and defines for the I2C API.
 *
 *  Copyright (c) 2022 Texas Instruments Incorporated
 *
 *  Redistribution and use in source and binary forms, with or without
 *  modification, are permitted provided that the following conditions are met:
 *
 *  1) Redistributions of source code must retain the above copyright notice,
 *     this list of conditions and the following disclaimer.
 *
 *  2) Redistributions in binary form must reproduce the above copyright notice,
 *     this list of conditions and the following disclaimer in the documentation
 *     and/or other materials provided with the distribution.
 *
 *  3) Neither the name of the copyright holder nor the names of its
 *     contributors may be used to endorse or promote products derived from this
 *     software without specific prior written permission.
 *
 *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 *  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 *  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 *  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
 *  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 *  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 *  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 *  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 *  POSSIBILITY OF SUCH DAMAGE.
 *
 ******************************************************************************/

#ifndef __I2C_H__
#define __I2C_H__

//*****************************************************************************
//
//
//*****************************************************************************

//*****************************************************************************
//
// If building with a C++ compiler, make all of the definitions in this header
// have a C binding.
//
//*****************************************************************************
#ifdef __cplusplus
extern "C" {
#endif

#include <stdbool.h>
#include <stdint.h>
#include "../inc/hw_types.h"
#include "../inc/hw_ints.h"
#include "../inc/hw_memmap.h"
#include "../inc/hw_i2c.h"
#include "debug.h"
#include "interrupt.h"
#include "cpu.h"

//*****************************************************************************
//
// I2C Controller commands
//
//*****************************************************************************
#define I2C_CONTROLLER_CMD_SINGLE_SEND              0x00000007
#define I2C_CONTROLLER_CMD_SINGLE_RECEIVE           0x00000007
#define I2C_CONTROLLER_CMD_BURST_SEND_START         0x00000003
#define I2C_CONTROLLER_CMD_BURST_SEND_CONT          0x00000001
#define I2C_CONTROLLER_CMD_BURST_SEND_FINISH        0x00000005
#define I2C_CONTROLLER_CMD_BURST_SEND_ERROR_STOP    0x00000004
#define I2C_CONTROLLER_CMD_BURST_RECEIVE_START      0x0000000b
#define I2C_CONTROLLER_CMD_BURST_RECEIVE_CONT       0x00000009
#define I2C_CONTROLLER_CMD_BURST_RECEIVE_FINISH     0x00000005
#define I2C_CONTROLLER_CMD_BURST_RECEIVE_ERROR_STOP 0x00000004

//*****************************************************************************
//
// I2C Controller error status
//
//*****************************************************************************
#define I2C_CONTROLLER_ERR_NONE     0
#define I2C_CONTROLLER_ERR_ADDR_ACK 0x00000004
#define I2C_CONTROLLER_ERR_DATA_ACK 0x00000008
#define I2C_CONTROLLER_ERR_ARB_LOST 0x00000010

//*****************************************************************************
//
// I2C Target action requests
//
//*****************************************************************************
#define I2C_TARGET_ACT_NONE     0
#define I2C_TARGET_ACT_RREQ     0x00000001 // Controller has sent data
#define I2C_TARGET_ACT_TREQ     0x00000002 // Controller has requested data
#define I2C_TARGET_ACT_RREQ_FBR 0x00000005 // Controller has sent first byte

//*****************************************************************************
//
// I2C Target interrupts
//
//*****************************************************************************
#define I2C_TARGET_INT_STOP  0x00000004 // Stop Condition Interrupt.
#define I2C_TARGET_INT_START 0x00000002 // Start Condition Interrupt.
#define I2C_TARGET_INT_DATA  0x00000001 // Data Interrupt.

//*****************************************************************************
//
// I2C module clock frequency
//
//*****************************************************************************
#define I2C_CLK_FREQ 48000000 // Clock supplied to I2C periph in Hz

//*****************************************************************************
//
// API Functions and prototypes
//
//*****************************************************************************

#ifdef DRIVERLIB_DEBUG
//*****************************************************************************
//
//
//*****************************************************************************
static bool I2CBaseValid(uint32_t base)
{
    return (base == I2C0_BASE);
}
#endif

//*****************************************************************************
//
//
//*****************************************************************************
extern void I2CControllerInitExpClk(uint32_t base, bool fast);

//*****************************************************************************
//
//
//*****************************************************************************
__STATIC_INLINE void I2CControllerCommand(uint32_t base, uint32_t cmd)
{
    // Check the arguments.
    ASSERT(I2CBaseValid(base));
    ASSERT((cmd == I2C_CONTROLLER_CMD_SINGLE_SEND) ||
           //     (cmd == I2C_CONTROLLER_CMD_SINGLE_RECEIVE) || -> Equal to SINGLE_SEND
           (cmd == I2C_CONTROLLER_CMD_BURST_SEND_START) || (cmd == I2C_CONTROLLER_CMD_BURST_SEND_CONT) ||
           (cmd == I2C_CONTROLLER_CMD_BURST_SEND_FINISH) || (cmd == I2C_CONTROLLER_CMD_BURST_SEND_ERROR_STOP) ||
           (cmd == I2C_CONTROLLER_CMD_BURST_RECEIVE_START) || (cmd == I2C_CONTROLLER_CMD_BURST_RECEIVE_CONT) ||
           (cmd == I2C_CONTROLLER_CMD_BURST_RECEIVE_FINISH) || (cmd == I2C_CONTROLLER_CMD_BURST_RECEIVE_ERROR_STOP));

    // Send the command.
    HWREG(base + I2C_O_CCTL) = cmd;

    // Delay minimum four cycles in order to ensure that the I2C_O_CCTL
    // register has been correctly updated before function exit
    CPUDelay(2);
}

//*****************************************************************************
//
//
//*****************************************************************************
__STATIC_INLINE void I2CControllerSetTargetAddr(uint32_t base, uint8_t targetAddr, bool receive)
{
    // Check the arguments.
    ASSERT(I2CBaseValid(base));
    ASSERT(!(targetAddr & 0x80));

    // Set the address of the target with which the controller will communicate.
    HWREG(base + I2C_O_CTA) = (targetAddr << 1) | receive;
}

//*****************************************************************************
//
//
//*****************************************************************************
__STATIC_INLINE void I2CControllerEnable(uint32_t base)
{
    // Check the arguments.
    ASSERT(I2CBaseValid(base));

    // Enable the clock for the controller.
    HWREG(base + I2C_O_CCR) |= I2C_CCR_CFE_M;

    // Enable the controller module.
    HWREG(base + I2C_O_CCTL) = I2C_CCTL_RUN_EN;
}

//*****************************************************************************
//
//
//*****************************************************************************
__STATIC_INLINE void I2CControllerDisable(uint32_t base)
{
    // Check the arguments.
    ASSERT(I2CBaseValid(base));

    // Disable the controller module.
    HWREG(base + I2C_O_CCTL) = 0;

    // Disable the clock for the controller.
    HWREG(base + I2C_O_CCR) &= ~I2C_CCR_CFE_M;
}

//*****************************************************************************
//
//
//*****************************************************************************
__STATIC_INLINE bool I2CControllerBusy(uint32_t base)
{
    // Check the arguments.
    ASSERT(I2CBaseValid(base));

    // Return the busy status.
    if (HWREG(base + I2C_O_CSTA) & I2C_CSTA_BUSY_M)
    {
        return (true);
    }
    else
    {
        return (false);
    }
}

//*****************************************************************************
//
//
//*****************************************************************************
__STATIC_INLINE bool I2CControllerBusBusy(uint32_t base)
{
    // Check the arguments.
    ASSERT(I2CBaseValid(base));

    // Return the bus busy status.
    if (HWREG(base + I2C_O_CSTA) & I2C_CSTA_BUSBSY_M)
    {
        return (true);
    }
    else
    {
        return (false);
    }
}

//*****************************************************************************
//
//
//*****************************************************************************
__STATIC_INLINE uint32_t I2CControllerGetData(uint32_t base)
{
    // Check the arguments.
    ASSERT(I2CBaseValid(base));

    // Read a byte.
    return (HWREG(base + I2C_O_CDR));
}

//*****************************************************************************
//
//
//*****************************************************************************
__STATIC_INLINE void I2CControllerPutData(uint32_t base, uint8_t data)
{
    // Check the arguments.
    ASSERT(I2CBaseValid(base));

    // Write the byte.
    HWREG(base + I2C_O_CDR) = data;
}

//*****************************************************************************
//
//
//*****************************************************************************
extern uint32_t I2CControllerError(uint32_t base);

//*****************************************************************************
//
//
//*****************************************************************************
__STATIC_INLINE void I2CControllerEnableInt(uint32_t base)
{
    // Check the arguments.
    ASSERT(I2CBaseValid(base));

    // Enable the controller interrupt.
    HWREG(base + I2C_O_CIMR) = I2C_CIMR_IM;
}

//*****************************************************************************
//
//
//*****************************************************************************
__STATIC_INLINE void I2CControllerDisableInt(uint32_t base)
{
    // Check the arguments.
    ASSERT(I2CBaseValid(base));

    // Disable the controller interrupt.
    HWREG(base + I2C_O_CIMR) = 0;
}

//*****************************************************************************
//
//
//*****************************************************************************
__STATIC_INLINE void I2CControllerClearInt(uint32_t base)
{
    // Check the arguments.
    ASSERT(I2CBaseValid(base));

    // Clear the I2C controller interrupt source.
    HWREG(base + I2C_O_CICR) = I2C_CICR_IC;
}

//*****************************************************************************
//
//
//*****************************************************************************
__STATIC_INLINE bool I2CControllerIntStatus(uint32_t base, bool masked)
{
    // Check the arguments.
    ASSERT(I2CBaseValid(base));

    // Return either the interrupt status or the raw interrupt status as
    // requested.
    if (masked)
    {
        return ((HWREG(base + I2C_O_CMIS)) ? true : false);
    }
    else
    {
        return ((HWREG(base + I2C_O_CRIS)) ? true : false);
    }
}

//*****************************************************************************
//
//
//*****************************************************************************
__STATIC_INLINE void I2CTargetEnable(uint32_t base)
{
    // Check the arguments.
    ASSERT(I2CBaseValid(base));

    // Enable the clock to the target module.
    HWREG(base + I2C_O_CCR) |= I2C_CCR_TFE_M;

    // Enable the target.
    HWREG(base + I2C_O_TCTL) = I2C_TCTL_DA_EN;
}

//*****************************************************************************
//
//
//*****************************************************************************
__STATIC_INLINE void I2CTargetInit(uint32_t base, uint8_t targetAddr)
{
    // Check the arguments.
    ASSERT(I2CBaseValid(base));
    ASSERT(!(targetAddr & 0x80));

    // Must enable the device before doing anything else.
    I2CTargetEnable(base);

    // Set up the target address.
    HWREG(base + I2C_O_TOAR) = targetAddr;
}

//*****************************************************************************
//
//
//*****************************************************************************
__STATIC_INLINE void I2CTargetSetAddress(uint32_t base, uint8_t targetAddr)
{
    // Check the arguments.
    ASSERT(I2CBaseValid(base));
    ASSERT(!(targetAddr & 0x80));

    // Set up the primary target address.
    HWREG(base + I2C_O_TOAR) = targetAddr;
}

//*****************************************************************************
//
//
//*****************************************************************************
__STATIC_INLINE void I2CTargetDisable(uint32_t base)
{
    // Check the arguments.
    ASSERT(I2CBaseValid(base));

    // Disable the target.
    HWREG(base + I2C_O_TCTL) = 0x0;

    // Disable the clock to the target module.
    HWREG(base + I2C_O_CCR) &= ~I2C_CCR_TFE_M;
}

//*****************************************************************************
//
//
//*****************************************************************************
__STATIC_INLINE uint32_t I2CTargetStatus(uint32_t base)
{
    // Check the arguments.
    ASSERT(I2CBaseValid(base));

    // Return the target status.
    return (HWREG(base + I2C_O_TSTA));
}

//*****************************************************************************
//
//
//*****************************************************************************
__STATIC_INLINE uint32_t I2CTargetGetData(uint32_t base)
{
    // Check the arguments.
    ASSERT(I2CBaseValid(base));

    // Read a byte.
    return (HWREG(base + I2C_O_TDR));
}

//*****************************************************************************
//
//
//*****************************************************************************
__STATIC_INLINE void I2CTargetPutData(uint32_t base, uint8_t data)
{
    // Check the arguments.
    ASSERT(I2CBaseValid(base));

    // Write the byte.
    HWREG(base + I2C_O_TDR) = data;
}

//*****************************************************************************
//
//
//*****************************************************************************
__STATIC_INLINE void I2CTargetEnableInt(uint32_t base, uint32_t intFlags)
{
    uint32_t val;

    // Check the arguments.
    ASSERT(I2CBaseValid(base));
    ASSERT(intFlags & (I2C_TARGET_INT_STOP | I2C_TARGET_INT_START | I2C_TARGET_INT_DATA));

    // Enable the target interrupt.
    val = HWREG(base + I2C_O_TIMR);
    val |= intFlags;
    HWREG(base + I2C_O_TIMR) = val;
}

//*****************************************************************************
//
//
//*****************************************************************************
__STATIC_INLINE void I2CTargetDisableInt(uint32_t base, uint32_t intFlags)
{
    uint32_t val;

    // Check the arguments.
    ASSERT(I2CBaseValid(base));
    ASSERT(intFlags & (I2C_TARGET_INT_STOP | I2C_TARGET_INT_START | I2C_TARGET_INT_DATA));

    // Disable the target interrupt.
    val = HWREG(base + I2C_O_TIMR);
    val &= ~intFlags;
    HWREG(base + I2C_O_TIMR) = val;
}

//*****************************************************************************
//
//
//*****************************************************************************
__STATIC_INLINE void I2CTargetClearInt(uint32_t base, uint32_t intFlags)
{
    // Check the arguments.
    ASSERT(I2CBaseValid(base));

    // Clear the I2C target interrupt source.
    HWREG(base + I2C_O_TICR) = intFlags;
}

//*****************************************************************************
//
//
//*****************************************************************************
__STATIC_INLINE uint32_t I2CTargetIntStatus(uint32_t base, bool masked)
{
    // Check the arguments.
    ASSERT(I2CBaseValid(base));

    // Return either the interrupt status or the raw interrupt status as
    // requested.
    if (masked)
    {
        return (HWREG(base + I2C_O_TMIS));
    }
    else
    {
        return (HWREG(base + I2C_O_TRIS));
    }
}

//*****************************************************************************
//
// Mark the end of the C bindings section for C++ compilers.
//
//*****************************************************************************
#ifdef __cplusplus
}
#endif

//*****************************************************************************
//
//
//*****************************************************************************

#endif // __I2C_H__