circuitpython/ports/esp32s2/common-hal/alarm/touch/TouchAlarm.c

/*
 * This file is part of the MicroPython project, http://micropython.org/
 *
 * The MIT License (MIT)
 *
 * Copyright (c) 2020 microDev
 *
 * 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 "shared-bindings/alarm/touch/TouchAlarm.h"
#include "shared-bindings/microcontroller/__init__.h"

#include "esp_sleep.h"
#include "peripherals/touch.h"
#include "supervisor/esp_port.h"

static uint16_t touch_channel_mask;
static volatile bool woke_up = false;

void common_hal_alarm_touch_touchalarm_construct(alarm_touch_touchalarm_obj_t *self, const mcu_pin_obj_t *pin) {
    if (pin->touch_channel == TOUCH_PAD_MAX) {
        mp_raise_ValueError(translate("Invalid pin"));
    }
    claim_pin(pin);
    self->pin = pin;
}

mp_obj_t alarm_touch_touchalarm_get_wakeup_alarm(const size_t n_alarms, const mp_obj_t *alarms) {
    // First, check to see if we match any given alarms.
    for (size_t i = 0; i < n_alarms; i++) {
        if (mp_obj_is_type(alarms[i], &alarm_touch_touchalarm_type)) {
            return alarms[i];
        }
    }

    // Create TouchAlarm object.
    alarm_touch_touchalarm_obj_t *alarm = m_new_obj(alarm_touch_touchalarm_obj_t);
    alarm->base.type = &alarm_touch_touchalarm_type;
    alarm->pin = NULL;

    touch_pad_t wake_channel = touch_pad_get_current_meas_channel();
    if (wake_channel == TOUCH_PAD_MAX) {
        return alarm;
    }

    // Map the pin number back to a pin object.
    for (size_t i = 0; i < mcu_pin_globals.map.used; i++) {
        const mcu_pin_obj_t *pin_obj = MP_OBJ_TO_PTR(mcu_pin_globals.map.table[i].value);
        if (pin_obj->touch_channel == wake_channel) {
            alarm->pin = mcu_pin_globals.map.table[i].value;
            break;
        }
    }

    return alarm;
}

// This is used to wake the main CircuitPython task.
void touch_interrupt(void *arg) {
    (void)arg;
    woke_up = true;
    BaseType_t task_wakeup;
    vTaskNotifyGiveFromISR(circuitpython_task, &task_wakeup);
    if (task_wakeup) {
        portYIELD_FROM_ISR();
    }
}

void alarm_touch_touchalarm_set_alarm(const bool deep_sleep, const size_t n_alarms, const mp_obj_t *alarms) {
    bool touch_alarm_set = false;
    alarm_touch_touchalarm_obj_t *touch_alarm = MP_OBJ_NULL;

    for (size_t i = 0; i < n_alarms; i++) {
        if (mp_obj_is_type(alarms[i], &alarm_touch_touchalarm_type)) {
            if (deep_sleep && touch_alarm_set) {
                mp_raise_ValueError(translate("Only one TouchAlarm can be set in deep sleep."));
            }
            touch_alarm = MP_OBJ_TO_PTR(alarms[i]);
            touch_channel_mask |= 1 << touch_alarm->pin->number;
            touch_alarm_set = true;
        }
    }

    if (!touch_alarm_set) {
        return;
    }

    // configure interrupt for pretend to deep sleep
    // this will be disabled if we actually deep sleep

    // reset touch peripheral
    peripherals_touch_reset();
    peripherals_touch_never_reset(true);

    for (uint8_t i = 1; i <= 14; i++) {
        if ((touch_channel_mask & 1 << i) != 0) {
            touch_pad_t touch_channel = (touch_pad_t)i;
            // intialize touchpad
            peripherals_touch_init(touch_channel);

            // wait for touch data to reset
            mp_hal_delay_ms(10);

            // configure trigger threshold
            uint32_t touch_value;
            touch_pad_read_benchmark(touch_channel, &touch_value);
            touch_pad_set_thresh(touch_channel, touch_value * 0.1); // 10%
        }
    }

    // configure touch interrupt
    touch_pad_timeout_set(true, SOC_TOUCH_PAD_THRESHOLD_MAX);
    touch_pad_isr_register(touch_interrupt, NULL, TOUCH_PAD_INTR_MASK_ALL);
    touch_pad_intr_enable(TOUCH_PAD_INTR_MASK_ACTIVE | TOUCH_PAD_INTR_MASK_INACTIVE);
}

void alarm_touch_touchalarm_prepare_for_deep_sleep(void) {
    if (!touch_channel_mask) {
        return;
    }

    touch_pad_t touch_channel = TOUCH_PAD_MAX;
    for (uint8_t i = 1; i <= 14; i++) {
        if ((touch_channel_mask & 1 << i) != 0) {
            touch_channel = (touch_pad_t)i;
            break;
        }
    }

    // reset touch peripheral
    peripherals_touch_never_reset(false);
    peripherals_touch_reset();

    // intialize touchpad
    peripherals_touch_init(touch_channel);

    // configure touchpad for sleep
    touch_pad_sleep_channel_enable(touch_channel, true);
    touch_pad_sleep_channel_enable_proximity(touch_channel, false);

    // wait for touch data to reset
    mp_hal_delay_ms(10);

    // configure trigger threshold
    uint32_t touch_value;
    touch_pad_sleep_channel_read_smooth(touch_channel, &touch_value);
    touch_pad_sleep_set_threshold(touch_channel, touch_value * 0.1); // 10%

    // enable touchpad wakeup
    esp_sleep_enable_touchpad_wakeup();
    esp_sleep_pd_config(ESP_PD_DOMAIN_RTC_PERIPH, ESP_PD_OPTION_ON);
}

bool alarm_touch_touchalarm_woke_us_up(void) {
    return woke_up;
}

void alarm_touch_touchalarm_reset(void) {
    woke_up = false;
    touch_channel_mask = 0;
    peripherals_touch_never_reset(false);
}