adc_hal.c

/*
 * SPDX-FileCopyrightText: 2019-2022 Espressif Systems (Shanghai) CO LTD
 *
 * SPDX-License-Identifier: Apache-2.0
 */

#include <sys/param.h>
#include "sdkconfig.h"
#include "hal/adc_hal.h"
#include "hal/adc_hal_conf.h"
#include "hal/assert.h"
#include "soc/lldesc.h"
#include "soc/soc_caps.h"

#if CONFIG_IDF_TARGET_ESP32
//ADC utilises I2S0 DMA on ESP32
#include "hal/i2s_hal.h"
#include "hal/i2s_ll.h"
#include "hal/i2s_types.h"
#include "soc/i2s_struct.h"
#endif

#if CONFIG_IDF_TARGET_ESP32S2
//ADC utilises SPI3 DMA on ESP32S2
#include "hal/spi_ll.h"
#include "soc/spi_struct.h"
#endif

#if SOC_ADC_DIG_CTRL_SUPPORTED && !SOC_ADC_RTC_CTRL_SUPPORTED
/*---------------------------------------------------------------
                    Single Read
---------------------------------------------------------------*/
/**
 * For chips without RTC controller, Digital controller is used to trigger an ADC single read.
 */
#include "esp_rom_sys.h"

typedef enum {
    ADC_EVENT_ADC1_DONE = BIT(0),
    ADC_EVENT_ADC2_DONE = BIT(1),
} adc_hal_event_t;
#endif  //SOC_ADC_DIG_CTRL_SUPPORTED && !SOC_ADC_RTC_CTRL_SUPPORTED

/*---------------------------------------------------------------
            Define all ADC DMA required operations here
---------------------------------------------------------------*/
#if SOC_GDMA_SUPPORTED
#define adc_dma_ll_rx_clear_intr(dev, chan, mask)       gdma_ll_rx_clear_interrupt_status(dev, chan, mask)
#define adc_dma_ll_rx_enable_intr(dev, chan, mask)      gdma_ll_rx_enable_interrupt(dev, chan, mask, true)
#define adc_dma_ll_rx_disable_intr(dev, chan, mask)     gdma_ll_rx_enable_interrupt(dev, chan, mask, false)
#define adc_dma_ll_rx_reset_channel(dev, chan)          gdma_ll_rx_reset_channel(dev, chan)
#define adc_dma_ll_rx_stop(dev, chan)                   gdma_ll_rx_stop(dev, chan)
#define adc_dma_ll_rx_start(dev, chan, addr) do { \
            gdma_ll_rx_set_desc_addr(dev, chan, (uint32_t)addr); \
            gdma_ll_rx_start(dev, chan); \
        } while (0)
#define adc_ll_digi_dma_set_eof_num(dev, num)           adc_ll_digi_dma_set_eof_num(num)
#define adc_ll_digi_reset(dev)                          adc_ll_digi_reset()
#define adc_ll_digi_trigger_enable(dev)                 adc_ll_digi_trigger_enable()
#define adc_ll_digi_trigger_disable(dev)                adc_ll_digi_trigger_disable()

//ADC utilises SPI3 DMA on ESP32S2
#elif CONFIG_IDF_TARGET_ESP32S2
#define adc_dma_ll_rx_get_intr(dev, mask)               spi_ll_get_intr(dev, mask)
#define adc_dma_ll_rx_clear_intr(dev, chan, mask)       spi_ll_clear_intr(dev, mask)
#define adc_dma_ll_rx_enable_intr(dev, chan, mask)      spi_ll_enable_intr(dev, mask)
#define adc_dma_ll_rx_disable_intr(dev, chan, mask)     spi_ll_disable_intr(dev, mask)
#define adc_dma_ll_rx_reset_channel(dev, chan)          spi_dma_ll_rx_reset(dev, chan)
#define adc_dma_ll_rx_stop(dev, chan)                   spi_dma_ll_rx_stop(dev, chan)
#define adc_dma_ll_rx_start(dev, chan, addr)            spi_dma_ll_rx_start(dev, chan, addr)
#define adc_dma_ll_get_in_suc_eof_desc_addr(dev, chan)  spi_dma_ll_get_in_suc_eof_desc_addr(dev, chan)
#define adc_ll_digi_dma_set_eof_num(dev, num)           adc_ll_digi_dma_set_eof_num(num)
#define adc_ll_digi_reset(dev)                          adc_ll_digi_reset()
#define adc_ll_digi_trigger_enable(dev)                 adc_ll_digi_trigger_enable()
#define adc_ll_digi_trigger_disable(dev)                adc_ll_digi_trigger_disable()

//ADC utilises I2S0 DMA on ESP32
#else //CONFIG_IDF_TARGET_ESP32
#define adc_dma_ll_rx_get_intr(dev, mask)               ({i2s_ll_get_intr_status(dev) & mask;})
#define adc_dma_ll_rx_clear_intr(dev, chan, mask)       i2s_ll_clear_intr_status(dev, mask)
#define adc_dma_ll_rx_enable_intr(dev, chan, mask)      do {((i2s_dev_t *)(dev))->int_ena.val |= mask;} while (0)
#define adc_dma_ll_rx_disable_intr(dev, chan, mask)     do {((i2s_dev_t *)(dev))->int_ena.val &= ~mask;} while (0)
#define adc_dma_ll_rx_reset_channel(dev, chan)          i2s_ll_rx_reset_dma(dev)
#define adc_dma_ll_rx_stop(dev, chan)                   i2s_ll_rx_stop_link(dev)
#define adc_dma_ll_rx_start(dev, chan, address) do { \
            ((i2s_dev_t *)(dev))->in_link.addr = (uint32_t)(address); \
            i2s_ll_enable_dma(dev, 1); \
            ((i2s_dev_t *)(dev))->in_link.start = 1; \
        } while (0)
#define adc_dma_ll_get_in_suc_eof_desc_addr(dev, chan)  ({uint32_t addr; i2s_ll_rx_get_eof_des_addr(dev, &addr); addr;})
#define adc_ll_digi_dma_set_eof_num(dev, num)            do {((i2s_dev_t *)(dev))->rx_eof_num = num;} while (0)
#define adc_ll_digi_reset(dev) do { \
            i2s_ll_rx_reset(dev); \
            i2s_ll_rx_reset_fifo(dev); \
        } while (0)
#define adc_ll_digi_trigger_enable(dev)                 i2s_ll_rx_start(dev)
#define adc_ll_digi_trigger_disable(dev)                i2s_ll_rx_stop(dev)
#define adc_ll_digi_dma_enable()                        adc_ll_digi_set_data_source(1)  //Will this influence I2S0
#define adc_ll_digi_dma_disable()                       adc_ll_digi_set_data_source(0)

//ESP32 ADC uses the DMA through I2S. The I2S needs to be configured.
#define I2S_BASE_CLK                                    (2*APB_CLK_FREQ)
#define SAMPLE_BITS                                     16
#define ADC_LL_CLKM_DIV_NUM_DEFAULT                     2
#define ADC_LL_CLKM_DIV_B_DEFAULT                       0
#define ADC_LL_CLKM_DIV_A_DEFAULT                       1

#endif


void adc_hal_init(void)
{
    // Set internal FSM wait time, fixed value.
    adc_ll_digi_set_fsm_time(SOC_ADC_FSM_RSTB_WAIT_DEFAULT, SOC_ADC_FSM_START_WAIT_DEFAULT,
                             SOC_ADC_FSM_STANDBY_WAIT_DEFAULT);
    adc_ll_set_sample_cycle(ADC_FSM_SAMPLE_CYCLE_DEFAULT);
    adc_hal_pwdet_set_cct(SOC_ADC_PWDET_CCT_DEFAULT);
    adc_ll_digi_output_invert(ADC_NUM_1, SOC_ADC_DIGI_DATA_INVERT_DEFAULT(ADC_NUM_1));
    adc_ll_digi_output_invert(ADC_NUM_2, SOC_ADC_DIGI_DATA_INVERT_DEFAULT(ADC_NUM_2));
    adc_ll_digi_set_clk_div(SOC_ADC_DIGI_SAR_CLK_DIV_DEFAULT);
}

#if SOC_ADC_ARBITER_SUPPORTED
void adc_hal_arbiter_config(adc_arbiter_t *config)
{
    adc_ll_set_arbiter_work_mode(config->mode);
    adc_ll_set_arbiter_priority(config->rtc_pri, config->dig_pri, config->pwdet_pri);
}
#endif  // #if SOC_ADC_ARBITER_SUPPORTED

void adc_hal_digi_deinit(adc_hal_context_t *hal)
{
    adc_ll_digi_trigger_disable(hal->dev);
    adc_ll_digi_dma_disable();
    adc_ll_digi_clear_pattern_table(ADC_NUM_1);
    adc_ll_digi_clear_pattern_table(ADC_NUM_2);
    adc_ll_digi_reset(hal->dev);
    adc_ll_digi_controller_clk_disable();
}

/*---------------------------------------------------------------
                    Controller Setting
---------------------------------------------------------------*/
static adc_ll_controller_t get_controller(adc_ll_num_t unit, adc_hal_work_mode_t work_mode)
{
    if (unit == ADC_NUM_1) {
        switch (work_mode) {
#if SOC_ULP_SUPPORTED
            case ADC_HAL_ULP_MODE:
                return ADC_LL_CTRL_ULP;
#endif
            case ADC_HAL_SINGLE_READ_MODE:
#if SOC_ADC_DIG_CTRL_SUPPORTED && !SOC_ADC_RTC_CTRL_SUPPORTED
                return ADC_LL_CTRL_DIG;
#elif SOC_ADC_RTC_CTRL_SUPPORTED
                return ADC_LL_CTRL_RTC;
#endif
            case ADC_HAL_CONTINUOUS_READ_MODE:
                return ADC_LL_CTRL_DIG;
            default:
                abort();
        }
    } else {
        switch (work_mode) {
#if SOC_ULP_SUPPORTED
            case ADC_HAL_ULP_MODE:
                return ADC_LL_CTRL_ULP;
#endif
#if !SOC_ADC_ARBITER_SUPPORTED                  //No ADC2 arbiter on ESP32
            case ADC_HAL_SINGLE_READ_MODE:
                return ADC_LL_CTRL_RTC;
            case ADC_HAL_CONTINUOUS_READ_MODE:
                return ADC_LL_CTRL_DIG;
            case ADC_HAL_PWDET_MODE:
                return ADC_LL_CTRL_PWDET;
            default:
                abort();
#else
            default:
                return ADC_LL_CTRL_ARB;
#endif
        }
    }
}

void adc_hal_set_controller(adc_ll_num_t unit, adc_hal_work_mode_t work_mode)
{
    adc_ll_controller_t ctrlr = get_controller(unit, work_mode);
    adc_ll_set_controller(unit, ctrlr);
}

/*---------------------------------------------------------------
                    DMA read
---------------------------------------------------------------*/
static adc_ll_digi_convert_mode_t get_convert_mode(adc_digi_convert_mode_t convert_mode)
{
#if CONFIG_IDF_TARGET_ESP32
    return ADC_LL_DIGI_CONV_ONLY_ADC1;
#endif
#if (SOC_ADC_DIGI_CONTROLLER_NUM == 1)
    return ADC_LL_DIGI_CONV_ALTER_UNIT;
#elif (SOC_ADC_DIGI_CONTROLLER_NUM >= 2)
    switch (convert_mode) {
        case ADC_CONV_SINGLE_UNIT_1:
            return ADC_LL_DIGI_CONV_ONLY_ADC1;
        case ADC_CONV_SINGLE_UNIT_2:
            return ADC_LL_DIGI_CONV_ONLY_ADC2;
        case ADC_CONV_BOTH_UNIT:
            return ADC_LL_DIGI_CONV_BOTH_UNIT;
        case ADC_CONV_ALTER_UNIT:
            return ADC_LL_DIGI_CONV_ALTER_UNIT;
        default:
            abort();
    }
#endif
}

/**
 * For esp32s2 and later chips
 * - Set ADC digital controller clock division factor. The clock is divided from `APLL` or `APB` clock.
 *   Expression: controller_clk = APLL/APB * (div_num  + div_a / div_b + 1).
 * - Enable clock and select clock source for ADC digital controller.
 * For esp32, use I2S clock
 */
static void adc_hal_digi_sample_freq_config(adc_hal_context_t *hal, uint32_t freq)
{
#if !CONFIG_IDF_TARGET_ESP32
    uint32_t interval = APB_CLK_FREQ / (ADC_LL_CLKM_DIV_NUM_DEFAULT + ADC_LL_CLKM_DIV_A_DEFAULT / ADC_LL_CLKM_DIV_B_DEFAULT + 1) / 2 / freq;
    //set sample interval
    adc_ll_digi_set_trigger_interval(interval);
    //Here we set the clock divider factor to make the digital clock to 5M Hz
    adc_ll_digi_controller_clk_div(ADC_LL_CLKM_DIV_NUM_DEFAULT, ADC_LL_CLKM_DIV_B_DEFAULT, ADC_LL_CLKM_DIV_A_DEFAULT);
    adc_ll_digi_clk_sel(0);   //use APB
#else
    i2s_ll_rx_clk_set_src(hal->dev, I2S_CLK_D2CLK);    /*!< Clock from PLL_D2_CLK(160M)*/
    uint32_t bclk_div = 16;
    uint32_t bclk = freq * 2;
    uint32_t mclk = bclk * bclk_div;
    uint32_t mclk_div = I2S_BASE_CLK / mclk;
    i2s_hal_clock_cfg_t i2s_hal_clk_cfg = {
        .sclk = I2S_BASE_CLK,
        .bclk = bclk,
        .bclk_div = bclk_div,
        .mclk = mclk ,
        .mclk_div = mclk_div,
    };
    i2s_ll_mclk_div_t mclk_set = {};
    i2s_hal_mclk_div_decimal_cal(&i2s_hal_clk_cfg, &mclk_set);
    i2s_ll_rx_set_clk(hal->dev, &mclk_set);
    i2s_ll_rx_set_bck_div_num(hal->dev, i2s_hal_clk_cfg.bclk_div);
#endif
}

void adc_hal_digi_controller_config(adc_hal_context_t *hal, const adc_hal_digi_ctrlr_cfg_t *cfg)
{
#if (SOC_ADC_DIGI_CONTROLLER_NUM == 1)
    //Only one pattern table, this variable is for readability
    const int pattern_both = 0;

    adc_ll_digi_clear_pattern_table(pattern_both);
    adc_ll_digi_set_pattern_table_len(pattern_both, cfg->adc_pattern_len);
    for (int i = 0; i < cfg->adc_pattern_len; i++) {
        adc_ll_digi_set_pattern_table(pattern_both, i, cfg->adc_pattern[i]);
    }

#elif (SOC_ADC_DIGI_CONTROLLER_NUM >= 2)
    uint32_t adc1_pattern_idx = 0;
    uint32_t adc2_pattern_idx = 0;

    adc_ll_digi_clear_pattern_table(ADC_NUM_1);
    adc_ll_digi_clear_pattern_table(ADC_NUM_2);

    for (int i = 0; i < cfg->adc_pattern_len; i++) {
        if (cfg->adc_pattern[i].unit == ADC_NUM_1) {
            adc_ll_digi_set_pattern_table(ADC_NUM_1, adc1_pattern_idx, cfg->adc_pattern[i]);
            adc1_pattern_idx++;
        } else if (cfg->adc_pattern[i].unit == ADC_NUM_2) {
            adc_ll_digi_set_pattern_table(ADC_NUM_2, adc2_pattern_idx, cfg->adc_pattern[i]);
            adc2_pattern_idx++;
        } else {
            abort();
        }
    }
    adc_ll_digi_set_pattern_table_len(ADC_NUM_1, adc1_pattern_idx);
    adc_ll_digi_set_pattern_table_len(ADC_NUM_2, adc2_pattern_idx);

#endif

    if (cfg->conv_limit_en) {
        adc_ll_digi_set_convert_limit_num(cfg->conv_limit_num);
        adc_ll_digi_convert_limit_enable();
    } else {
        adc_ll_digi_convert_limit_disable();
    }

    adc_ll_digi_set_convert_mode(get_convert_mode(cfg->conv_mode));

    //clock and sample frequency
    adc_hal_digi_sample_freq_config(hal, cfg->sample_freq_hz);
}

void adc_hal_context_config(adc_hal_context_t *hal, const adc_hal_config_t *config)
{
    hal->desc_dummy_head.next = hal->rx_desc;
    hal->dev = config->dev;
    hal->eof_desc_num = config->eof_desc_num;
    hal->eof_step = config->eof_step;
    hal->dma_chan = config->dma_chan;
    hal->eof_num = config->eof_num;
}

void adc_hal_digi_init(adc_hal_context_t *hal)
{
    adc_dma_ll_rx_clear_intr(hal->dev, hal->dma_chan, ADC_HAL_DMA_INTR_MASK);
    adc_dma_ll_rx_enable_intr(hal->dev, hal->dma_chan, ADC_HAL_DMA_INTR_MASK);
    adc_ll_digi_dma_set_eof_num(hal->dev, hal->eof_num);
#if CONFIG_IDF_TARGET_ESP32
    i2s_ll_rx_set_sample_bit(hal->dev, SAMPLE_BITS, SAMPLE_BITS);
    i2s_ll_rx_enable_mono_mode(hal->dev, 1);
    i2s_ll_rx_force_enable_fifo_mod(hal->dev, 1);
    i2s_ll_enable_builtin_adc(hal->dev, 1);
#endif
#if CONFIG_IDF_TARGET_ESP32C3
    adc_ll_onetime_sample_enable(ADC_NUM_1, false);
    adc_ll_onetime_sample_enable(ADC_NUM_2, false);
#endif
}

static void adc_hal_digi_dma_link_descriptors(dma_descriptor_t *desc, uint8_t *data_buf, uint32_t per_eof_size, uint32_t eof_step, uint32_t eof_num)
{
    HAL_ASSERT(((uint32_t)data_buf % 4) == 0);
    HAL_ASSERT((per_eof_size % 4) == 0);
    uint32_t n = 0;
    dma_descriptor_t *desc_head = desc;

    while (eof_num--) {
        uint32_t eof_size = per_eof_size;

        for (int i = 0; i < eof_step; i++) {
            uint32_t this_len = eof_size;
            if (this_len > DMA_DESCRIPTOR_BUFFER_MAX_SIZE_4B_ALIGNED) {
                this_len = DMA_DESCRIPTOR_BUFFER_MAX_SIZE_4B_ALIGNED;
            }

            desc[n] = (dma_descriptor_t) {
                .dw0.size = this_len,
                .dw0.length = 0,
                .dw0.suc_eof = 0,
                .dw0.owner = 1,
                .buffer = data_buf,
                .next = &desc[n+1]
            };
            eof_size -= this_len;
            data_buf += this_len;
            n++;
        }
    }
    desc[n-1].next = desc_head;
}

void adc_hal_digi_start(adc_hal_context_t *hal, uint8_t *data_buf)
{
    //stop peripheral and DMA
    adc_hal_digi_stop(hal);

    //reset DMA
    adc_dma_ll_rx_reset_channel(hal->dev, hal->dma_chan);
    //reset peripheral
    adc_ll_digi_reset(hal->dev);

    //reset the current descriptor address
    hal->cur_desc_ptr = &hal->desc_dummy_head;
    adc_hal_digi_dma_link_descriptors(hal->rx_desc, data_buf, hal->eof_num * SOC_ADC_DIGI_DATA_BYTES_PER_CONV, hal->eof_step, hal->eof_desc_num);

    //start DMA
    adc_dma_ll_rx_start(hal->dev, hal->dma_chan, (lldesc_t *)hal->rx_desc);
    //connect DMA and peripheral
    adc_ll_digi_dma_enable();
    //start ADC
    adc_ll_digi_trigger_enable(hal->dev);
}

#if !SOC_GDMA_SUPPORTED
intptr_t adc_hal_get_desc_addr(adc_hal_context_t *hal)
{
    return adc_dma_ll_get_in_suc_eof_desc_addr(hal->dev, hal->dma_chan);
}

bool adc_hal_check_event(adc_hal_context_t *hal, uint32_t mask)
{
    return adc_dma_ll_rx_get_intr(hal->dev, mask);
}
#endif  //#if !SOC_GDMA_SUPPORTED

adc_hal_dma_desc_status_t adc_hal_get_reading_result(adc_hal_context_t *hal, const intptr_t eof_desc_addr, uint8_t **buffer, uint32_t *len)
{
    HAL_ASSERT(hal->cur_desc_ptr);

    if (!hal->cur_desc_ptr->next) {
        return ADC_HAL_DMA_DESC_NULL;
    }

    if ((intptr_t)hal->cur_desc_ptr == eof_desc_addr) {
        return ADC_HAL_DMA_DESC_WAITING;
    }

    uint8_t *buffer_start = NULL;
    uint32_t eof_len = 0;
    dma_descriptor_t *eof_desc = hal->cur_desc_ptr;

    //Find the eof list start
    eof_desc = eof_desc->next;
    eof_desc->dw0.owner = 1;
    buffer_start = eof_desc->buffer;
    eof_len += eof_desc->dw0.length;
    if ((intptr_t)eof_desc == eof_desc_addr) {
        goto valid;
    }

    //Find the eof list end
    for (int i = 1; i < hal->eof_step; i++) {
        eof_desc = eof_desc->next;
        eof_desc->dw0.owner = 1;
        eof_len += eof_desc->dw0.length;
        if ((intptr_t)eof_desc == eof_desc_addr) {
            goto valid;
        }
    }


valid:
    hal->cur_desc_ptr = eof_desc;
    *buffer = buffer_start;
    *len = eof_len;

    return ADC_HAL_DMA_DESC_VALID;
}

void adc_hal_digi_clr_intr(adc_hal_context_t *hal, uint32_t mask)
{
    adc_dma_ll_rx_clear_intr(hal->dev, hal->dma_chan, mask);
}

void adc_hal_digi_dis_intr(adc_hal_context_t *hal, uint32_t mask)
{
    adc_dma_ll_rx_disable_intr(hal->dev, hal->dma_chan, mask);
}

void adc_hal_digi_stop(adc_hal_context_t *hal)
{
    //stop ADC
    adc_ll_digi_trigger_disable(hal->dev);
    //stop DMA
    adc_dma_ll_rx_stop(hal->dev, hal->dma_chan);
    //disconnect DMA and peripheral
    adc_ll_digi_dma_disable();
}

#if SOC_ADC_DIG_CTRL_SUPPORTED && !SOC_ADC_RTC_CTRL_SUPPORTED
/*---------------------------------------------------------------
                    Single Read
---------------------------------------------------------------*/
/**
 * For chips without RTC controller, Digital controller is used to trigger an ADC single read.
 */

//--------------------INTR-------------------------------//
static adc_ll_intr_t get_event_intr(adc_hal_event_t event)
{
    adc_ll_intr_t intr_mask = 0;
    if (event & ADC_EVENT_ADC1_DONE) {
        intr_mask |= ADC_LL_INTR_ADC1_DONE;
    }
    if (event & ADC_EVENT_ADC2_DONE) {
        intr_mask |= ADC_LL_INTR_ADC2_DONE;
    }
    return intr_mask;
}

static void adc_hal_intr_clear(adc_hal_event_t event)
{
    adc_ll_intr_clear(get_event_intr(event));
}

static bool adc_hal_intr_get_raw(adc_hal_event_t event)
{
    return adc_ll_intr_get_raw(get_event_intr(event));
}


//--------------------Single Read-------------------------------//
static void adc_hal_onetime_start(void)
{
    adc_ll_digi_controller_clk_div(ADC_LL_CLKM_DIV_NUM_DEFAULT, ADC_LL_CLKM_DIV_B_DEFAULT, ADC_LL_CLKM_DIV_A_DEFAULT);
    adc_ll_digi_set_clk_div(SOC_ADC_DIGI_SAR_CLK_DIV_DEFAULT);
    /**
     * There is a hardware limitation. If the APB clock frequency is high, the step of this reg signal: ``onetime_start`` may not be captured by the
     * ADC digital controller (when its clock frequency is too slow). A rough estimate for this step should be at least 3 ADC digital controller
     * clock cycle.
     *
     * This limitation will be removed in hardware future versions.
     *
     */
    uint32_t digi_clk = APB_CLK_FREQ / (ADC_LL_CLKM_DIV_NUM_DEFAULT + ADC_LL_CLKM_DIV_A_DEFAULT / ADC_LL_CLKM_DIV_B_DEFAULT + 1);
    //Convert frequency to time (us). Since decimals are removed by this division operation. Add 1 here in case of the fact that delay is not enough.
    uint32_t delay = (1000 * 1000) / digi_clk + 1;
    //3 ADC digital controller clock cycle
    delay = delay * 3;
    //This coefficient (8) is got from test. When digi_clk is not smaller than ``APB_CLK_FREQ/8``, no delay is needed.
    if (digi_clk >= APB_CLK_FREQ/8) {
        delay = 0;
    }

    adc_ll_onetime_start(false);
    esp_rom_delay_us(delay);
    adc_ll_onetime_start(true);

    //No need to delay here. Becuase if the start signal is not seen, there won't be a done intr.
}

static esp_err_t adc_hal_single_read(adc_ll_num_t adc_n, int *out_raw)
{
    if (adc_n == ADC_NUM_1) {
        *out_raw = adc_ll_adc1_read();
    } else if (adc_n == ADC_NUM_2) {
        *out_raw = adc_ll_adc2_read();
        if (adc_ll_analysis_raw_data(adc_n, *out_raw)) {
            return ESP_ERR_INVALID_STATE;
        }
    }
    return ESP_OK;
}

esp_err_t adc_hal_convert(adc_ll_num_t adc_n, int channel, int *out_raw)
{
    esp_err_t ret;
    adc_hal_event_t event;

    if (adc_n == ADC_NUM_1) {
        event = ADC_EVENT_ADC1_DONE;
    } else {
        event = ADC_EVENT_ADC2_DONE;
    }

    adc_hal_intr_clear(event);
    adc_ll_onetime_sample_enable(ADC_NUM_1, false);
    adc_ll_onetime_sample_enable(ADC_NUM_2, false);
    adc_ll_onetime_sample_enable(adc_n, true);
    adc_ll_onetime_set_channel(adc_n, channel);

    //Trigger single read.
    adc_hal_onetime_start();
    while (!adc_hal_intr_get_raw(event));
    ret = adc_hal_single_read(adc_n, out_raw);
    //HW workaround: when enabling periph clock, this should be false
    adc_ll_onetime_sample_enable(adc_n, false);

    return ret;
}

#else   // #if SOC_ADC_RTC_CTRL_SUPPORTED
esp_err_t adc_hal_convert(adc_ll_num_t adc_n, int channel, int *out_raw)
{
    adc_ll_rtc_enable_channel(adc_n, channel);
    adc_ll_rtc_start_convert(adc_n, channel);
    while (adc_ll_rtc_convert_is_done(adc_n) != true);
    *out_raw = adc_ll_rtc_get_convert_value(adc_n);

    if ((int)adc_ll_rtc_analysis_raw_data(adc_n, (uint16_t)(*out_raw))) {
        return ESP_ERR_INVALID_STATE;
    }

    return ESP_OK;
}
#endif  //#if SOC_ADC_DIG_CTRL_SUPPORTED && !SOC_ADC_RTC_CTRL_SUPPORTED


/*---------------------------------------------------------------
                    ADC calibration setting
---------------------------------------------------------------*/
#if SOC_ADC_CALIBRATION_V1_SUPPORTED
void adc_hal_calibration_init(adc_ll_num_t adc_n)
{
    adc_ll_calibration_init(adc_n);
}

static uint32_t s_previous_init_code[SOC_ADC_PERIPH_NUM] = {-1, -1};

void adc_hal_set_calibration_param(adc_ll_num_t adc_n, uint32_t param)
{
    if (param != s_previous_init_code[adc_n]) {
        adc_ll_set_calibration_param(adc_n, param);
        s_previous_init_code[adc_n] = param;
    }
}

#if SOC_ADC_RTC_CTRL_SUPPORTED
static void cal_setup(adc_ll_num_t adc_n, adc_channel_t channel, adc_atten_t atten, bool internal_gnd)
{
    adc_hal_set_controller(adc_n, ADC_HAL_SINGLE_READ_MODE);    //Set controller

    /* Enable/disable internal connect GND (for calibration). */
    if (internal_gnd) {
        adc_ll_rtc_disable_channel(adc_n);
        adc_ll_set_atten(adc_n, 0, atten);  // Note: when disable all channel, HW auto select channel0 atten param.
    } else {
        adc_ll_rtc_enable_channel(adc_n, channel);
        adc_ll_set_atten(adc_n, channel, atten);
    }
}

static uint32_t read_cal_channel(adc_ll_num_t adc_n, int channel)
{
    adc_ll_rtc_start_convert(adc_n, channel);
    while (adc_ll_rtc_convert_is_done(adc_n) != true);
    return (uint32_t)adc_ll_rtc_get_convert_value(adc_n);
}

//For those RTC controller not supported chips, they use digital controller to do the single read. e.g.: esp32c3
#elif SOC_ADC_DIG_CTRL_SUPPORTED && !SOC_ADC_RTC_CTRL_SUPPORTED
static void cal_setup(adc_ll_num_t adc_n, adc_channel_t channel, adc_atten_t atten, bool internal_gnd)
{
    adc_ll_onetime_sample_enable(ADC_NUM_1, false);
    adc_ll_onetime_sample_enable(ADC_NUM_2, false);
    /* Enable/disable internal connect GND (for calibration). */
    if (internal_gnd) {
        const int esp32c3_invalid_chan = (adc_n == ADC_NUM_1)? 0xF: 0x1;
        adc_ll_onetime_set_channel(adc_n, esp32c3_invalid_chan);
    } else {
        adc_ll_onetime_set_channel(adc_n, channel);
    }
    adc_ll_onetime_set_atten(atten);
    adc_ll_onetime_sample_enable(adc_n, true);
}

static uint32_t read_cal_channel(adc_ll_num_t adc_n, int channel)
{
    adc_ll_intr_clear(ADC_LL_INTR_ADC1_DONE | ADC_LL_INTR_ADC2_DONE);
    adc_ll_onetime_start(false);
    esp_rom_delay_us(5);
    adc_ll_onetime_start(true);

    while(!adc_ll_intr_get_raw(ADC_LL_INTR_ADC1_DONE | ADC_LL_INTR_ADC2_DONE));

    uint32_t read_val = -1;
    if (adc_n == ADC_NUM_1) {
        read_val = adc_ll_adc1_read();
    } else if (adc_n == ADC_NUM_2) {
        read_val = adc_ll_adc2_read();
        if (adc_ll_analysis_raw_data(adc_n, read_val)) {
            return -1;
        }
    }
    return read_val;
}
#endif //Do single read via DIGI controller or RTC controller

#define ADC_HAL_CAL_TIMES        (10)
#define ADC_HAL_CAL_OFFSET_RANGE (4096)

uint32_t adc_hal_self_calibration(adc_ll_num_t adc_n, adc_channel_t channel, adc_atten_t atten, bool internal_gnd)
{
    if (adc_n == ADC_NUM_2) {
        adc_arbiter_t config = ADC_ARBITER_CONFIG_DEFAULT();
        adc_hal_arbiter_config(&config);
    }

    cal_setup(adc_n, channel, atten, internal_gnd);

    adc_ll_calibration_prepare(adc_n, channel, internal_gnd);

    uint32_t code_list[ADC_HAL_CAL_TIMES] = {0};
    uint32_t code_sum = 0;
    uint32_t code_h = 0;
    uint32_t code_l = 0;
    uint32_t chk_code = 0;

    for (uint8_t rpt = 0 ; rpt < ADC_HAL_CAL_TIMES ; rpt ++) {
        code_h = ADC_HAL_CAL_OFFSET_RANGE;
        code_l = 0;
        chk_code = (code_h + code_l) / 2;
        adc_ll_set_calibration_param(adc_n, chk_code);
        uint32_t self_cal = read_cal_channel(adc_n, channel);
        while (code_h - code_l > 1) {
            if (self_cal == 0) {
                code_h = chk_code;
            } else {
                code_l = chk_code;
            }
            chk_code = (code_h + code_l) / 2;
            adc_ll_set_calibration_param(adc_n, chk_code);
            self_cal = read_cal_channel(adc_n, channel);
            if ((code_h - code_l == 1)) {
                chk_code += 1;
                adc_ll_set_calibration_param(adc_n, chk_code);
                self_cal = read_cal_channel(adc_n, channel);
            }
        }
        code_list[rpt] = chk_code;
        code_sum += chk_code;
    }

    code_l = code_list[0];
    code_h = code_list[0];
    for (uint8_t i = 0 ; i < ADC_HAL_CAL_TIMES ; i++) {
        code_l = MIN(code_l, code_list[i]);
        code_h = MAX(code_h, code_list[i]);
    }

    chk_code = code_h + code_l;
    uint32_t ret = ((code_sum - chk_code) % (ADC_HAL_CAL_TIMES - 2) < 4)
           ? (code_sum - chk_code) / (ADC_HAL_CAL_TIMES - 2)
           : (code_sum - chk_code) / (ADC_HAL_CAL_TIMES - 2) + 1;

    adc_ll_calibration_finish(adc_n);
    return ret;
}
#endif //SOC_ADC_CALIBRATION_V1_SUPPORTED