esp32-hal-sigmadelta.c

/*
 * SPDX-FileCopyrightText: 2019-2023 Espressif Systems (Shanghai) CO LTD
 *
 * SPDX-License-Identifier: Apache-2.0
 */

#include "esp32-hal-sigmadelta.h"

#if SOC_SDM_SUPPORTED
#include "esp32-hal.h"
#include "esp32-hal-periman.h"
#include "driver/sdm.h"

static bool sigmaDeltaDetachBus(void *bus) {
  esp_err_t err = sdm_channel_disable((sdm_channel_handle_t)bus);
  if (err != ESP_OK) {
    log_w("sdm_channel_disable failed with error: %d", err);
  }
  err = sdm_del_channel((sdm_channel_handle_t)bus);
  if (err != ESP_OK) {
    log_e("sdm_del_channel failed with error: %d", err);
    return false;
  }
  return true;
}

bool sigmaDeltaAttach(uint8_t pin, uint32_t freq)  //freq 1220-312500
{
  perimanSetBusDeinit(ESP32_BUS_TYPE_SIGMADELTA, sigmaDeltaDetachBus);
  sdm_channel_handle_t bus = NULL;
  // pin may be previously attached to other peripheral -> detach it.
  // if attached to sigmaDelta, detach it and set the new frequency
  if (perimanGetPinBusType(pin) != ESP32_BUS_TYPE_INIT && !perimanClearPinBus(pin)) {
    log_e("Pin %u could not be detached.", pin);
    return false;
  }
  sdm_config_t config = {.gpio_num = (int)pin, .clk_src = SDM_CLK_SRC_DEFAULT, .sample_rate_hz = freq, .flags = {.invert_out = 0, .io_loop_back = 0}};
  esp_err_t err = sdm_new_channel(&config, &bus);
  if (err != ESP_OK) {
    log_e("sdm_new_channel failed with error: %d", err);
    return false;
  }
  err = sdm_channel_enable(bus);
  if (err != ESP_OK) {
    sigmaDeltaDetachBus((void *)bus);
    log_e("sdm_channel_enable failed with error: %d", err);
    return false;
  }
  if (!perimanSetPinBus(pin, ESP32_BUS_TYPE_SIGMADELTA, (void *)bus, -1, -1)) {
    sigmaDeltaDetachBus((void *)bus);
    return false;
  }
  return true;
}

bool sigmaDeltaWrite(uint8_t pin, uint8_t duty)  //chan 0-x according to SOC duty 8 bit
{
  sdm_channel_handle_t bus = (sdm_channel_handle_t)perimanGetPinBus(pin, ESP32_BUS_TYPE_SIGMADELTA);
  if (bus != NULL) {
    int8_t d = duty - 128;
    esp_err_t err = sdm_channel_set_duty(bus, d);
    if (err != ESP_OK) {
      log_e("sdm_channel_set_duty failed with error: %d", err);
      return false;
    }
    return true;
  } else {
    log_e("pin %u is not attached to SigmaDelta", pin);
  }
  return false;
}

bool sigmaDeltaDetach(uint8_t pin) {
  void *bus = perimanGetPinBus(pin, ESP32_BUS_TYPE_SIGMADELTA);
  if (bus != NULL) {
    // will call sigmaDeltaDetachBus
    return perimanClearPinBus(pin);
  } else {
    log_e("pin %u is not attached to SigmaDelta", pin);
  }
  return false;
}
#endif