esp32-hal-dac.c

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

#include "esp32-hal-dac.h"

#if SOC_DAC_SUPPORTED
#include "esp32-hal.h"
#include "esp32-hal-periman.h"
#include "soc/dac_channel.h"
#include "driver/dac_oneshot.h"

static bool dacDetachBus(void *bus) {
  esp_err_t err = dac_oneshot_del_channel((dac_oneshot_handle_t)bus);
  if (err != ESP_OK) {
    log_e("dac_oneshot_del_channel failed with error: %d", err);
    return false;
  }
  return true;
}

bool __dacWrite(uint8_t pin, uint8_t value) {
  esp_err_t err = ESP_OK;
  if (pin != DAC_CHAN0_GPIO_NUM && pin != DAC_CHAN1_GPIO_NUM) {
    log_e("pin %u is not a DAC pin", pin);
    return false;  //not dac pin
  }

  dac_oneshot_handle_t bus = (dac_oneshot_handle_t)perimanGetPinBus(pin, ESP32_BUS_TYPE_DAC_ONESHOT);
  if (bus == NULL) {
    perimanSetBusDeinit(ESP32_BUS_TYPE_DAC_ONESHOT, dacDetachBus);
    if (!perimanClearPinBus(pin)) {
      return false;
    }
    dac_channel_t channel = (pin == DAC_CHAN0_GPIO_NUM) ? DAC_CHAN_0 : DAC_CHAN_1;
    dac_oneshot_config_t config = {.chan_id = channel};
    err = dac_oneshot_new_channel(&config, &bus);
    if (err != ESP_OK) {
      log_e("dac_oneshot_new_channel failed with error: %d", err);
      return false;
    }
    if (!perimanSetPinBus(pin, ESP32_BUS_TYPE_DAC_ONESHOT, (void *)bus, -1, channel)) {
      dacDetachBus((void *)bus);
      return false;
    }
  }

  err = dac_oneshot_output_voltage(bus, value);
  if (err != ESP_OK) {
    log_e("dac_oneshot_output_voltage failed with error: %d", err);
    return false;
  }
  return true;
}

bool __dacDisable(uint8_t pin) {
  if (pin != DAC_CHAN0_GPIO_NUM && pin != DAC_CHAN1_GPIO_NUM) {
    log_e("pin %u is not a DAC pin", pin);
    return false;  //not dac pin
  }
  void *bus = perimanGetPinBus(pin, ESP32_BUS_TYPE_DAC_ONESHOT);
  if (bus != NULL) {
    // will call dacDetachBus
    return perimanClearPinBus(pin);
  } else {
    log_e("pin %u is not attached to DAC", pin);
  }
  return false;
}

extern bool dacWrite(uint8_t pin, uint8_t value) __attribute__((weak, alias("__dacWrite")));
extern bool dacDisable(uint8_t pin) __attribute__((weak, alias("__dacDisable")));

#endif