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/* ----------------------------------------------------------------------------

 *         ATMEL Microcontroller Software Support

 * ----------------------------------------------------------------------------

 * Copyright (c) 2008, Atmel Corporation

 *

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions are met:

 *

 * - Redistributions of source code must retain the above copyright notice,

 * this list of conditions and the disclaimer below.

 *

 * Atmel's name may not be used to endorse or promote products derived from

 * this software without specific prior written permission.

 *

 * DISCLAIMER: THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR

 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF

 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE

 * DISCLAIMED. IN NO EVENT SHALL ATMEL 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.

 * ----------------------------------------------------------------------------

 */

//------------------------------------------------------------------------------

//         Headers

//------------------------------------------------------------------------------

#include "pio.h"

#include <board.h>

//------------------------------------------------------------------------------

//         Internal definitions

//------------------------------------------------------------------------------

/// \internal Returns the current value of a register.

#define READ(peripheral, register)          (peripheral->register)

/// \internal Modifies the current value of a register.

#define WRITE(peripheral, register, value)  (peripheral->register = value)

//------------------------------------------------------------------------------

//         Internal functions

//------------------------------------------------------------------------------

//------------------------------------------------------------------------------

/// Configures one or more pin(s) of a PIO controller as being controlled by

/// peripheral A. Optionally, the corresponding internal pull-up(s) can be

/// enabled.

/// \param pio  Pointer to a PIO controller.

/// \param mask  Bitmask of one or more pin(s) to configure.

/// \param enablePullUp  Indicates if the pin(s) internal pull-up shall be

///                      configured.

//------------------------------------------------------------------------------

static void PIO_SetPeripheralA(AT91S_PIO *pio,

                               unsigned int mask,

                               unsigned char enablePullUp)

{

    // Disable interrupts on the pin(s)

    WRITE(pio, PIO_IDR, mask);

    // Enable the pull-up(s) if necessary

    if (enablePullUp) {

        WRITE(pio, PIO_PPUER, mask);

    }

    else {

        WRITE(pio, PIO_PPUDR, mask);

    }

    // Configure pin

    WRITE(pio, PIO_ASR, mask);

    WRITE(pio, PIO_PDR, mask);

}

//------------------------------------------------------------------------------

/// Configures one or more pin(s) of a PIO controller as being controlled by

/// peripheral A. Optionally, the corresponding internal pull-up(s) can be

/// enabled.

/// \param pio  Pointer to a PIO controller.

/// \param mask  Bitmask of one or more pin(s) to configure.

/// \param enablePullUp  Indicates if the pin(s) internal pull-up shall be

///                      configured.

//------------------------------------------------------------------------------

static void PIO_SetPeripheralB(AT91S_PIO *pio,

                               unsigned int mask,

                               unsigned char enablePullUp)

{

    // Disable interrupts on the pin(s)

    WRITE(pio, PIO_IDR, mask);

    // Enable the pull-up(s) if necessary

    if (enablePullUp) {

        WRITE(pio, PIO_PPUER, mask);

    }

    else {

        WRITE(pio, PIO_PPUDR, mask);

    }

    // Configure pin

    WRITE(pio, PIO_BSR, mask);

    WRITE(pio, PIO_PDR, mask);

}

//------------------------------------------------------------------------------

/// Configures one or more pin(s) or a PIO controller as inputs. Optionally,

/// the corresponding internal pull-up(s) and glitch filter(s) can be

/// enabled.

/// \param pio  Pointer to a PIO controller.

/// \param mask  Bitmask indicating which pin(s) to configure as input(s).

/// \param enablePullUp  Indicates if the internal pull-up(s) must be enabled.

/// \param enableFilter  Indicates if the glitch filter(s) must be enabled.

//------------------------------------------------------------------------------

static void PIO_SetInput(AT91S_PIO *pio,

                         unsigned int mask,

                         unsigned char enablePullUp,

                         unsigned char enableFilter)

{

    // Disable interrupts

    WRITE(pio, PIO_IDR, mask);

    // Enable pull-up(s) if necessary

    if (enablePullUp) {

        WRITE(pio, PIO_PPUER, mask);

    }

    else {

        WRITE(pio, PIO_PPUDR, mask);

    }

    // Enable filter(s) if necessary

    if (enableFilter) {

        WRITE(pio, PIO_IFER, mask);

    }

    else {

        WRITE(pio, PIO_IFDR, mask);

    }

    // Configure pin as input

    WRITE(pio, PIO_ODR, mask);

    WRITE(pio, PIO_PER, mask);

}

//------------------------------------------------------------------------------

/// Configures one or more pin(s) of a PIO controller as outputs, with the

/// given default value. Optionally, the multi-drive feature can be enabled

/// on the pin(s).

/// \param pio  Pointer to a PIO controller.

/// \param mask  Bitmask indicating which pin(s) to configure.

/// \param defaultValue  Default level on the pin(s).

/// \param enableMultiDrive  Indicates if the pin(s) shall be configured as

///                          open-drain.

/// \param enablePullUp  Indicates if the pin shall have its pull-up activated.

//------------------------------------------------------------------------------

static void PIO_SetOutput(AT91S_PIO *pio,

                          unsigned int mask,

                          unsigned char defaultValue,

                          unsigned char enableMultiDrive,

                          unsigned char enablePullUp)

{

    // Disable interrupts

    WRITE(pio, PIO_IDR, mask);

    // Enable pull-up(s) if necessary

    if (enablePullUp) {

        WRITE(pio, PIO_PPUER, mask);

    }

    else {

        WRITE(pio, PIO_PPUDR, mask);

    }

    // Enable multi-drive if necessary

    if (enableMultiDrive) {

        WRITE(pio, PIO_MDER, mask);

    }

    else {

        WRITE(pio, PIO_MDDR, mask);

    }

    // Set default value

    if (defaultValue) {

        WRITE(pio, PIO_SODR, mask);

    }

    else {

        WRITE(pio, PIO_CODR, mask);

    }

    // Configure pin(s) as output(s)

    WRITE(pio, PIO_OER, mask);

    WRITE(pio, PIO_PER, mask);

}

//------------------------------------------------------------------------------

//         Exported functions

//------------------------------------------------------------------------------

//------------------------------------------------------------------------------

/// Configures a list of Pin instances, which can either hold a single pin or a 

/// group of pins, depending on the mask value; all pins are configured by this 

/// function.

/// Returns 1 if the configuration has been performed successfully; otherwise 0.

/// \param list  Pointer to a list of Pin instances.

/// \param size  Size of the Pin list (see <PIO_LISTSIZE>).

//------------------------------------------------------------------------------

unsigned char PIO_Configure(const Pin *list, unsigned int size)

{

    // Configure pins

    while (size > 0) {

        switch (list->type) {

            case PIO_PERIPH_A:

                PIO_SetPeripheralA(list->pio,

                                   list->mask,

                                   (list->attribute & PIO_PULLUP) ? 1 : 0);

                break;

            case PIO_PERIPH_B:

                PIO_SetPeripheralB(list->pio,

                                   list->mask,

                                   (list->attribute & PIO_PULLUP) ? 1 : 0);

                break;

            case PIO_INPUT:

                AT91C_BASE_PMC->PMC_PCER = 1 << list->id;

                PIO_SetInput(list->pio,

                             list->mask,

                             (list->attribute & PIO_PULLUP) ? 1 : 0,

                             (list->attribute & PIO_DEGLITCH)? 1 : 0);

                break;

            case PIO_OUTPUT_0:

            case PIO_OUTPUT_1:

                PIO_SetOutput(list->pio,

                              list->mask,

                              (list->type == PIO_OUTPUT_1),

                              (list->attribute & PIO_OPENDRAIN) ? 1 : 0,

                              (list->attribute & PIO_PULLUP) ? 1 : 0);

                break;

            default: return 0;

        }

        list++;

        size--;

    }

    return 1;

}

//------------------------------------------------------------------------------

/// Sets a high output level on one or more pin(s) (if configured as output(s)).

/// \param pin  Pointer to a Pin instance describing one or more pins.

//------------------------------------------------------------------------------

void PIO_Set(const Pin *pin)

{

    WRITE(pin->pio, PIO_SODR, pin->mask);

}

//------------------------------------------------------------------------------

/// Sets a low output level on one or more pin(s) (if configured as output(s)).

/// \param pin  Pointer to a Pin instance describing one or more pins.

//------------------------------------------------------------------------------

void PIO_Clear(const Pin *pin)

{

    WRITE(pin->pio, PIO_CODR, pin->mask);

}

//------------------------------------------------------------------------------

/// Returns 1 if one or more PIO of the given Pin instance currently have a high

/// level; otherwise returns 0.

/// \param pin  Pointer to a Pin instance describing one or more pins.

//------------------------------------------------------------------------------

unsigned char PIO_Get(const Pin *pin)

{

    unsigned int reg;

    if ((pin->type == PIO_OUTPUT_0) || (pin->type == PIO_OUTPUT_1)) {

        reg = READ(pin->pio, PIO_ODSR);

    }

    else {

        reg = READ(pin->pio, PIO_PDSR);

    }

    if ((reg & pin->mask) == 0) {

        return 0;

    }

    else {

        return 1;

    }

}

//------------------------------------------------------------------------------

/// Returns 1 if one or more PIO of the given Pin data to be driven on the I/O line

/// level; otherwise returns 0.

/// \param pin  Pointer to a Pin instance describing one or more pins.

//------------------------------------------------------------------------------

unsigned char PIO_GetOutputDataStatus(const Pin *pin)

{

    if ((READ(pin->pio, PIO_ODSR) & pin->mask) == 0) {

        return 0;

    }

    else {

        return 1;

    }

}

//------------------------------------------------------------------------------

/// Returns the value of ISR for the PIO controller of the pin.

/// Reading this register acknoledges all the ITs.

/// \param pin  Pointer to a Pin instance describing one or more pins.

//------------------------------------------------------------------------------

unsigned int PIO_GetISR(const Pin *pin)

{

    return (READ(pin->pio, PIO_ISR));

}