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/*
* This file is part of the MicroPython project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2019 Lucian Copeland for Adafruit Industries
* Uses code from Micropython, Copyright (c) 2013-2016 Damien P. George
*
* 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 THE
* AUTHORS OR COPYRIGHT HOLDERS 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.
*/
#include <math.h>
#include "common-hal/pulseio/PWMOut.h"
#include "shared-bindings/pulseio/PWMOut.h"
#include "py/runtime.h"
#include "driver/ledc.h"
#define INDEX_EMPTY 0xFF
STATIC uint32_t reserved_timer_freq[LEDC_TIMER_MAX];
STATIC uint8_t reserved_channels[LEDC_CHANNEL_MAX];
STATIC bool never_reset_tim[LEDC_TIMER_MAX];
STATIC bool never_reset_chan[LEDC_CHANNEL_MAX];
void pwmout_reset(void) {
for (size_t i = 0; i < LEDC_CHANNEL_MAX; i++ ) {
ledc_stop(LEDC_LOW_SPEED_MODE, i, 0);
if (!never_reset_chan[i]) {
reserved_channels[i] = INDEX_EMPTY;
}
}
for (size_t i = 0; i < LEDC_TIMER_MAX; i++ ) {
ledc_timer_rst(LEDC_LOW_SPEED_MODE, i);
if (!never_reset_tim[i]) {
reserved_timer_freq[i] = 0;
}
}
}
pwmout_result_t common_hal_pulseio_pwmout_construct(pulseio_pwmout_obj_t* self,
const mcu_pin_obj_t* pin,
uint16_t duty,
uint32_t frequency,
bool variable_frequency) {
// Calculate duty cycle
uint32_t duty_bits = 0;
uint32_t interval = LEDC_APB_CLK_HZ/frequency;
for (size_t i = 0; i < 32; i++) {
if(!(interval >> i)) {
duty_bits = i - 1;
break;
}
}
if (duty_bits < 1) {
mp_raise_ValueError(translate("Invalid frequency"));
} else if (duty_bits >= LEDC_TIMER_14_BIT) {
duty_bits = LEDC_TIMER_13_BIT;
}
// Find a viable timer
size_t timer_index = INDEX_EMPTY;
size_t channel_index = INDEX_EMPTY;
for (size_t i = 0; i < LEDC_TIMER_MAX; i++) {
if ((reserved_timer_freq[i] == frequency) && !variable_frequency) {
//prioritize matched frequencies so we don't needlessly take slots
timer_index = i;
break;
} else if (reserved_timer_freq[i] == 0) {
timer_index = i;
break;
}
}
if (timer_index == INDEX_EMPTY) {
// Running out of timers isn't pin related on ESP32S2 so we can't re-use error messages
mp_raise_ValueError(translate("No more timers available"));
}
// Find a viable channel
for (size_t i = 0; i < LEDC_CHANNEL_MAX; i++) {
if (reserved_channels[i] == INDEX_EMPTY) {
channel_index = i;
break;
}
}
if (channel_index == INDEX_EMPTY) {
mp_raise_ValueError(translate("No more channels available"));
}
// Run configuration
self->tim_handle.timer_num = timer_index;
self->tim_handle.duty_resolution = duty_bits;
self->tim_handle.freq_hz = frequency;
self->tim_handle.speed_mode = LEDC_LOW_SPEED_MODE;
self->tim_handle.clk_cfg = LEDC_AUTO_CLK;
if (ledc_timer_config(&(self->tim_handle)) != ESP_OK) {
mp_raise_ValueError(translate("Could not initialize timer"));
}
self->chan_handle.channel = channel_index;
self->chan_handle.duty = duty >> (16 - duty_bits);
self->chan_handle.gpio_num = pin->number;
self->chan_handle.speed_mode = LEDC_LOW_SPEED_MODE; // Only LS is allowed on ESP32-S2
self->chan_handle.hpoint = 0;
self->chan_handle.timer_sel = timer_index;
if (ledc_channel_config(&(self->chan_handle))) {
mp_raise_ValueError(translate("Could not initialize channel"));
}
// Make reservations
reserved_timer_freq[timer_index] = frequency;
reserved_channels[channel_index] = timer_index;
self->variable_frequency = variable_frequency;
self->pin_number = pin->number;
self->deinited = false;
self->duty_resolution = duty_bits;
claim_pin(pin);
// Set initial duty
common_hal_pulseio_pwmout_set_duty_cycle(self, duty);
return PWMOUT_OK;
}
void common_hal_pulseio_pwmout_never_reset(pulseio_pwmout_obj_t *self) {
never_reset_tim[self->tim_handle.timer_num] = true;
never_reset_chan[self->chan_handle.channel] = true;
}
void common_hal_pulseio_pwmout_reset_ok(pulseio_pwmout_obj_t *self) {
never_reset_tim[self->tim_handle.timer_num] = false;
never_reset_chan[self->chan_handle.channel] = false;
}
bool common_hal_pulseio_pwmout_deinited(pulseio_pwmout_obj_t* self) {
return self->deinited == true;
}
void common_hal_pulseio_pwmout_deinit(pulseio_pwmout_obj_t* self) {
if (common_hal_pulseio_pwmout_deinited(self)) {
return;
}
ledc_stop(LEDC_LOW_SPEED_MODE, self->chan_handle.channel, 0);
// Search if any other channel is using the timer
bool taken = false;
for (size_t i =0; i < LEDC_CHANNEL_MAX; i++) {
if (reserved_channels[i] == self->tim_handle.timer_num) {
taken = true;
}
}
// Variable frequency means there's only one channel on the timer
if (!taken || self->variable_frequency) {
ledc_timer_rst(LEDC_LOW_SPEED_MODE, self->tim_handle.timer_num);
reserved_timer_freq[self->tim_handle.timer_num] = 0;
}
reset_pin_number(self->pin_number);
reserved_channels[self->chan_handle.channel] = INDEX_EMPTY;
self->deinited = true;
}
void common_hal_pulseio_pwmout_set_duty_cycle(pulseio_pwmout_obj_t* self, uint16_t duty) {
ledc_set_duty(LEDC_LOW_SPEED_MODE, self->chan_handle.channel, duty >> (16 - self->duty_resolution));
ledc_update_duty(LEDC_LOW_SPEED_MODE, self->chan_handle.channel);
}
uint16_t common_hal_pulseio_pwmout_get_duty_cycle(pulseio_pwmout_obj_t* self) {
return ledc_get_duty(LEDC_LOW_SPEED_MODE, self->chan_handle.channel) << (16 - self->duty_resolution);
}
void common_hal_pulseio_pwmout_set_frequency(pulseio_pwmout_obj_t* self, uint32_t frequency) {
ledc_set_freq(LEDC_LOW_SPEED_MODE, self->tim_handle.timer_num, frequency);
}
uint32_t common_hal_pulseio_pwmout_get_frequency(pulseio_pwmout_obj_t* self) {
return ledc_get_freq(LEDC_LOW_SPEED_MODE, self->tim_handle.timer_num);
}
bool common_hal_pulseio_pwmout_get_variable_frequency(pulseio_pwmout_obj_t* self) {
return self->variable_frequency;
}
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