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/* Original files PwmOut.h and pwmout_api.h contained the following copyright */
/* mbed Microcontroller Library
 * Copyright (c) 2006-2013 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.
 */
 /* Original files PwmOut.h and pwmout_api.h combined and modified:
    23 April 2018 Maxim Integrated Products, Inc.
 */
  
#ifndef _MAX326XXFTHR_PWMOUT_H_
#define _MAX326XXFTHR_PWMOUT_H_

#include "mbed.h"
#include "PinNames.h"
#include "platform/mbed_critical.h"
#include "platform/mbed_power_mgmt.h"
#include "tmr_regs.h"

/**
 * @brief Timer based PWM output for the MAX326XXFTHR platform
 *
 * @details This library provides PWM output using the MAX326XX 32-bit timers.
 * The mbed PwmOut API implementation uses the MAX326XX Pulse Train peripherals.
 * The table below contains the available GPIO pins that can be connected to the
 * six 32-bit timers (TMR0-5).  Timer 0 is used for the microsecond ticker API
 * and is not available for PWM output.  On the MAX32630FTHR platform, 
 * timer 5 is used by the BLE API and will not be available for PWM output if 
 * the BLE API is used.
 *
 * MAX32620FTHR 32-Bit Timer PWM Mapping
 *
 * Timer | GPIO Port and Pin                                                <br>
 * TMR1  | P0_1, P0_7, P1_5,       P3_1,       P4_5, P5_3                   <br>
 * TMR2  | P0_2, P1_0, P1_6, P2_4, P3_2, P4_0, P4_6, P5_4                   <br>
 * TMR3  | P0_3  P1_1  P1_7, P2_5, P3_3,       P4_7, P5_5                   <br>
 * TMR4  | P0_4  P1_2        P2_6, P3_4,       P5_0, P5_6                   <br>
 * TMR5  | P0_5  P1_3        P2_7, P3_5,       P5_1, P5_7                   <br>
 * 
 * MAX32630FTHR 32-Bit Timer PWM Mapping
 *
 * Timer | GPIO Port and Pin                                                <br>
 * TMR1  |       P3_1,              P5_3                                    <br>
 * TMR2  | P2_4, P3_2,  P4_0,       P5_4                                    <br>
 * TMR3  | P2_5, P3_3,              P5_5                                    <br>
 * TMR4  | P2_6, P3_4,        P5_0, P5_6                                    <br>
 * TMR5  |       P3_5,        P5_1                                          <br>
 *
 * Note that for MAX32620FTHR and MAX32630FTHR GPIOs P2_4, P2_5 and P2_6 are 
 * connected to onboard LEDs 1, 2 and 3.
 *
 * @code
 * #include "mbed.h"
 * #include "MAX326XXFTHR_PwmOut.h"
 * 
 * MAX326XXFTHR_PwmOut led[] = {
 *     MAX326XXFTHR_PwmOut(LED1),
 *     MAX326XXFTHR_PwmOut(LED2),
 *     MAX326XXFTHR_PwmOut(LED3)
 * };
 * 
 * int main()
 * {
 *     float dc;
 *     unsigned int idx = 0;
 * 
 *     while (1) {
 *         for (dc = 0.0f; dc <= 1.0f; dc += 0.01f) {
 *             led[idx % 3].write(dc);
 *             led[(idx + 1) % 3].write(1.0f - dc);
 *             wait_ms(20);
 *         }
 *         idx++;
 *     }
 * }
 * @endcode
 */

class MAX326XXFTHR_PwmOut
{
public:
    
    /** Create a PwmOut connected to the specified pin
     *
     *  @param pin PwmOut pin to connect to
     */
    MAX326XXFTHR_PwmOut(PinName pin) : _deep_sleep_locked(false) {
        core_util_critical_section_enter();
        pwmout_init(pin);
        core_util_critical_section_exit();
    }

    ~MAX326XXFTHR_PwmOut() {
        core_util_critical_section_enter();
        unlock_deep_sleep();
        core_util_critical_section_exit();
    }

    /** Set the ouput duty-cycle, specified as a percentage (float)
     *
     *  @param value A floating-point value representing the output duty-cycle,
     *    specified as a percentage. The value should lie between
     *    0.0f (representing on 0%) and 1.0f (representing on 100%).
     *    Values outside this range will be saturated to 0.0f or 1.0f.
     */
    void write(float value) {
        core_util_critical_section_enter();
        lock_deep_sleep();
        pwmout_write(value);
        core_util_critical_section_exit();
    }

    /** Return the current output duty-cycle setting, measured as a percentage (float)
     *
     *  @returns
     *    A floating-point value representing the current duty-cycle being output on the pin,
     *    measured as a percentage. The returned value will lie between
     *    0.0f (representing on 0%) and 1.0f (representing on 100%).
     *
     *  @note
     *  This value may not match exactly the value set by a previous write().
     */
    float read() {
        core_util_critical_section_enter();
        float val = pwmout_read();
        core_util_critical_section_exit();
        return val;
    }

    /** Set the PWM period, specified in seconds (float), keeping the duty cycle the same.
     *
     *  @param seconds Change the period of a PWM signal in seconds (float) without modifying the duty cycle
     *  @note
     *   The resolution is currently in microseconds; periods smaller than this
     *   will be set to zero.
     */
    void period(float seconds) {
        core_util_critical_section_enter();
        pwmout_period(seconds);
        core_util_critical_section_exit();
    }

    /** Set the PWM period, specified in milli-seconds (int), keeping the duty cycle the same.
     *  @param ms Change the period of a PWM signal in milli-seconds without modifying the duty cycle
     */
    void period_ms(int ms) {
        core_util_critical_section_enter();
        pwmout_period_ms(ms);
        core_util_critical_section_exit();
    }

    /** Set the PWM period, specified in micro-seconds (int), keeping the duty cycle the same.
     *  @param us Change the period of a PWM signal in micro-seconds without modifying the duty cycle
     */
    void period_us(int us) {
        core_util_critical_section_enter();
        pwmout_period_us(us);
        core_util_critical_section_exit();
    }

    /** Set the PWM pulsewidth, specified in seconds (float), keeping the period the same.
     *  @param seconds Change the pulse width of a PWM signal specified in seconds (float)
     */
    void pulsewidth(float seconds) {
        core_util_critical_section_enter();
        pwmout_pulsewidth(seconds);
        core_util_critical_section_exit();
    }

    /** Set the PWM pulsewidth, specified in milli-seconds (int), keeping the period the same.
     *  @param ms Change the pulse width of a PWM signal specified in milli-seconds
     */
    void pulsewidth_ms(int ms) {
        core_util_critical_section_enter();
        pwmout_pulsewidth_ms(ms);
        core_util_critical_section_exit();
    }

    /** Set the PWM pulsewidth, specified in micro-seconds (int), keeping the period the same.
     *  @param us Change the pulse width of a PWM signal specified in micro-seconds
     */
    void pulsewidth_us(int us) {
        core_util_critical_section_enter();
        pwmout_pulsewidth_us(us);
        core_util_critical_section_exit();
    }

    /** A operator shorthand for write()
     *  \sa PwmOut::write()
     */
    MAX326XXFTHR_PwmOut& operator= (float value) {
        // Underlying call is thread safe
        write(value);
        return *this;
    }

    /** A operator shorthand for write()
     * \sa PwmOut::write()
     */
    MAX326XXFTHR_PwmOut& operator= (PwmOut& rhs) {
        // Underlying call is thread safe
        write(rhs.read());
        return *this;
    }

    /** An operator shorthand for read()
     * \sa PwmOut::read()
     */
    operator float() {
        // Underlying call is thread safe
        return read();
    }

protected:
    /** Lock deep sleep only if it is not yet locked */
    void lock_deep_sleep() {
        if (_deep_sleep_locked == false) {
            sleep_manager_lock_deep_sleep();
            _deep_sleep_locked = true;
        }
    }

    /** Unlock deep sleep in case it is locked */
    void unlock_deep_sleep() {
        if (_deep_sleep_locked == true) {
            sleep_manager_unlock_deep_sleep();
            _deep_sleep_locked = false;
        }
    }

    bool _deep_sleep_locked;

private:
    /** Initialize the pwm out peripheral and configure the pin
     *
     * @param obj The pwmout object to initialize
     * @param pin The pwmout pin to initialize
     */
    void pwmout_init(PinName pin);

    /** Deinitialize the pwmout object
     *
     * @param obj The pwmout object
     */
    void pwmout_free();

    /** Set the output duty-cycle in range <0.0f, 1.0f>
     *
     * Value 0.0f represents 0 percentage, 1.0f represents 100 percent.
     * @param obj     The pwmout object
     * @param percent The floating-point percentage number
     */
    void pwmout_write(float percent);

    /** Read the current float-point output duty-cycle
     *
     * @param obj The pwmout object
     * @return A floating-point output duty-cycle
     */
    float pwmout_read();

    /** Set the PWM period specified in seconds, keeping the duty cycle the same
     *
     * Periods smaller than microseconds (the lowest resolution) are set to zero.
     * @param obj     The pwmout object
     * @param seconds The floating-point seconds period
     */
    void pwmout_period(float seconds);

    /** Set the PWM period specified in miliseconds, keeping the duty cycle the same
     *
     * @param obj The pwmout object
     * @param ms  The milisecond period
     */
    void pwmout_period_ms(int ms);

    /** Set the PWM period specified in microseconds, keeping the duty cycle the same
     *
     * @param obj The pwmout object
     * @param us  The microsecond period
     */
    void pwmout_period_us(int us);

    /** Set the PWM pulsewidth specified in seconds, keeping the period the same.
     *
     * @param obj     The pwmout object
     * @param seconds The floating-point pulsewidth in seconds
     */
    void pwmout_pulsewidth(float seconds);

    /** Set the PWM pulsewidth specified in miliseconds, keeping the period the same.
     *
     * @param obj The pwmout object
     * @param ms  The floating-point pulsewidth in miliseconds
     */
    void pwmout_pulsewidth_ms(int ms);

    /** Set the PWM pulsewidth specified in microseconds, keeping the period the same.
     *
     * @param obj The pwmout object
     * @param us  The floating-point pulsewidth in microseconds
     */
    void pwmout_pulsewidth_us(int us);


    PinName pin;
    mxc_tmr_regs_t *tmr;
    int tmr_idx;
    int pwm_period;
    int pulse_width;
    int last_pulse_width;
    void pwmout_update(void);
};

#endif