snapclient/components/esp_peripherals/lib/touch/touch.c

/*
 * ESPRESSIF MIT License
 *
 * Copyright (c) 2018 <ESPRESSIF SYSTEMS (SHANGHAI) PTE LTD>
 *
 * Permission is hereby granted for use on all ESPRESSIF SYSTEMS products, in
 * which case, it is 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 "touch.h"

#include <stdio.h>
#include <string.h>
#include <sys/time.h>

#include "audio_mem.h"
#include "driver/gpio.h"
#include "driver/touch_pad.h"
#include "esp_log.h"
#include "freertos/FreeRTOS.h"
#include "freertos/queue.h"
#include "freertos/task.h"
#include "sdkconfig.h"
#include "sys/queue.h"

#define TOUCHPAD_TRIGGER_THRESHOLD 100
#define TOUCHPAD_FILTER_PERIOD (30)
#define TOUCHPAD_READ_INTERVAL_MS (TOUCHPAD_FILTER_PERIOD * 4)
#define TOUCHPAD_INTIALIZE_TIME_MS 1000
#define UPDATE_THRESHOLD_PERIOD_MS 200

static const char *TAG = "TOUCH";

typedef struct esp_touch_item {
  int touch_num;
  long long last_tap_tick;
  long long update_threshold_tick;
  long long last_read_tick;
  uint16_t last_read_value;
  uint16_t untouch_value;
  uint16_t threshold_value;
  bool long_tapped;
  bool tapped;
  STAILQ_ENTRY(esp_touch_item) entry;
} esp_touch_item_t;

struct esp_touch {
  int long_tap_time_ms;
  int touch_mask;
  int tap_threshold_percent;
  touch_intr_handler intr_fn;
  void *intr_context;
  STAILQ_HEAD(esp_touch_list, esp_touch_item) touch_list;
};

#ifdef periph_tick_get
#define tick_get periph_tick_get
#else
static long long tick_get() {
  struct timeval te;
  gettimeofday(&te, NULL);  // get current time
  long long milliseconds =
      te.tv_sec * 1000LL + te.tv_usec / 1000;  // calculate milliseconds
  return milliseconds;
}
#endif

static void touch_pad_isr_handler(void *arg) {
  esp_touch_handle_t touch = (esp_touch_handle_t)arg;
#if CONFIG_IDF_TARGET_ESP32
  touch_pad_clear_status();
#endif
  if (touch->intr_fn) {
    touch->intr_fn(touch->intr_context);
  }
}

esp_touch_handle_t esp_touch_init(touch_config_t *config) {
  esp_touch_handle_t touch = audio_calloc(1, sizeof(struct esp_touch));
  AUDIO_MEM_CHECK(TAG, touch, return NULL);

  if (config->touch_mask <= 0) {
    ESP_LOGE(TAG, "required at least 1 touch");
    return NULL;
  }

  touch->touch_mask = config->touch_mask;
  touch->long_tap_time_ms = config->long_tap_time_ms;
  touch->tap_threshold_percent = config->tap_threshold_percent;

  if (touch->long_tap_time_ms == 0) {
    touch->long_tap_time_ms = DEFAULT_LONG_TAP_TIME_MS;
  }

  if (touch->tap_threshold_percent == 0) {
    touch->tap_threshold_percent = DEFAULT_TOUCH_THRESHOLD_PERCENT;
  }
  bool _success = (touch_pad_init() == ESP_OK);

  AUDIO_MEM_CHECK(TAG, _success, {
    audio_free(touch);
    return NULL;
  });

  int touch_mask = touch->touch_mask;
  int touch_num = 0;
  int touch_index = 0;
  STAILQ_INIT(&touch->touch_list);
  while (touch_mask) {
    if (touch_mask & 0x01) {
      ESP_LOGD(TAG, "Mask = %x, current_mask = %x, idx=%d", touch->touch_mask,
               touch_mask, touch_num);
      esp_touch_item_t *new_touch = audio_calloc(1, sizeof(esp_touch_item_t));
      AUDIO_MEM_CHECK(TAG, new_touch, {
        esp_touch_destroy(touch);
        audio_free(touch);
        return NULL;
      });
      new_touch->touch_num = touch_num;
      new_touch->last_read_tick = tick_get() + touch_index * 10;
#if CONFIG_IDF_TARGET_ESP32
      touch_pad_config(touch_num, 0);
#elif CONFIG_IDF_TARGET_ESP32S2
      touch_pad_config(touch_num);
#endif
      if (config->touch_intr_handler) {
        touch_pad_set_thresh(touch_num, TOUCHPAD_TRIGGER_THRESHOLD);
      }
      STAILQ_INSERT_TAIL(&touch->touch_list, new_touch, entry);
      touch_index++;
    }
    touch_mask >>= 1;
    touch_num++;
  }
  touch->intr_fn = config->touch_intr_handler;
  touch->intr_context = config->intr_context;

  if (config->touch_intr_handler) {
#if CONFIG_IDF_TARGET_ESP32
    touch_pad_isr_register(touch_pad_isr_handler, touch);
    touch_pad_intr_enable();
#elif CONFIG_IDF_TARGET_ESP32S2
    touch_pad_isr_register(touch_pad_isr_handler, touch,
                           TOUCH_PAD_INTR_MASK_ALL);
    touch_pad_intr_enable(TOUCH_PAD_INTR_MASK_ALL);
#endif
  }
#if CONFIG_IDF_TARGET_ESP32
  touch_pad_filter_start(TOUCHPAD_FILTER_PERIOD);
#endif
  return touch;
}

static touch_status_t touch_get_state(esp_touch_handle_t touch,
                                      esp_touch_item_t *touch_item,
                                      long long tick) {
  if (tick - touch_item->last_read_tick < TOUCHPAD_READ_INTERVAL_MS) {
    return TOUCH_UNCHANGE;
  }

  touch_item->last_read_tick = tick;
  esp_err_t err = ESP_OK;
#if CONFIG_IDF_TARGET_ESP32
  err = touch_pad_read_filtered(touch_item->touch_num,
                                &touch_item->last_read_value);
#elif CONFIG_IDF_TARGET_ESP32S2
  err = ESP_OK;
#endif

  if (err != ESP_OK) {
    return TOUCH_UNCHANGE;
  }
  if (touch_item->untouch_value == 0) {
    touch_item->untouch_value = touch_item->last_read_value;
    int threshold_value =
        touch_item->untouch_value * touch->tap_threshold_percent / 100;
    touch_item->threshold_value = threshold_value;
  }

  if (!touch_item->tapped &&
      touch_item->last_read_value < touch_item->threshold_value) {
    touch_item->tapped = true;

  } else if (touch_item->tapped &&
             touch_item->last_read_value > touch_item->threshold_value) {
    touch_item->tapped = false;
  }

  // Update touch threshold
  if (tick - touch_item->update_threshold_tick > UPDATE_THRESHOLD_PERIOD_MS &&
      !touch_item->tapped) {
    touch_item->update_threshold_tick = tick;
    touch_item->untouch_value += touch_item->last_read_value;
    touch_item->untouch_value /= 2;
    int threshold_value =
        touch_item->untouch_value * touch->tap_threshold_percent / 100;
    touch_item->threshold_value = threshold_value;
    // ESP_LOGD(TAG, "UPDATE THRESHOLD[%d]=%d", touch_item->touch_num,
    // threshold_value);
  }

  if (touch_item->last_tap_tick == 0 && touch_item->tapped) {
    touch_item->last_tap_tick = tick_get();
    touch_item->long_tapped = false;
    ESP_LOGD(TAG, "TOUCH_TAPPED[%d] %d, threshold %d", touch_item->touch_num,
             touch_item->last_read_value, touch_item->threshold_value);
    return TOUCH_TAP;
  }

  if (!touch_item->tapped && touch_item->last_tap_tick &&
      tick_get() - touch_item->last_tap_tick > touch->long_tap_time_ms) {
    touch_item->last_tap_tick = 0;
    touch_item->long_tapped = false;
    ESP_LOGD(TAG, "TOUCH_LONG_RELEASE[%d] %d, threshold %d",
             touch_item->touch_num, touch_item->last_read_value,
             touch_item->threshold_value);
    return TOUCH_LONG_RELEASE;
  }

  if (!touch_item->tapped && touch_item->last_tap_tick) {
    touch_item->last_tap_tick = 0;
    touch_item->long_tapped = false;
    ESP_LOGD(TAG, "TOUCH_RELEASE[%d] %d, threshold %d", touch_item->touch_num,
             touch_item->last_read_value, touch_item->threshold_value);
    return TOUCH_RELEASE;
  }

  if (touch_item->long_tapped == false && touch_item->tapped &&
      tick_get() - touch_item->last_tap_tick > touch->long_tap_time_ms) {
    touch_item->long_tapped = true;
    ESP_LOGD(TAG, "TOUCH_LONG_TAP[%d] %d, threshold %d", touch_item->touch_num,
             touch_item->last_read_value, touch_item->threshold_value);
    return TOUCH_LONG_TAP;
  }
  return TOUCH_UNCHANGE;
}

bool esp_touch_read(esp_touch_handle_t touch, touch_result_t *result) {
  esp_touch_item_t *touch_item;
  touch_status_t touch_status;
  bool changed = false;
  memset(result, 0, sizeof(touch_result_t));
  int tmp;
  long long tick = tick_get();
  STAILQ_FOREACH(touch_item, &touch->touch_list, entry) {
    touch_status = touch_get_state(touch, touch_item, tick);
    switch (touch_status) {
      case TOUCH_UNCHANGE:
        break;
      case TOUCH_TAP:
        changed = true;
        tmp = 0x01;
        tmp <<= touch_item->touch_num;
        result->tap_mask |= tmp;
        break;
      case TOUCH_RELEASE:
        changed = true;
        tmp = 0x01;
        tmp <<= touch_item->touch_num;
        result->release_mask |= tmp;
        break;
      case TOUCH_LONG_RELEASE:
        changed = true;
        tmp = 0x01;
        tmp <<= touch_item->touch_num;
        result->long_release_mask |= tmp;
        break;
      case TOUCH_LONG_TAP:
        changed = true;
        tmp = 0x01;
        tmp <<= touch_item->touch_num;
        result->long_tap_mask |= tmp;
        break;
    }
  }
  return changed;
}

esp_err_t esp_touch_destroy(esp_touch_handle_t touch) {
  esp_touch_item_t *touch_item, *tmp;
#if CONFIG_IDF_TARGET_ESP32
  touch_pad_filter_delete();
  touch_pad_intr_disable();
#elif CONFIG_IDF_TARGET_ESP32S2
  touch_pad_intr_disable(TOUCH_PAD_INTR_MASK_ALL);
#endif

  touch_pad_isr_deregister(touch_pad_isr_handler, touch);
  STAILQ_FOREACH_SAFE(touch_item, &touch->touch_list, entry, tmp) {
    STAILQ_REMOVE(&touch->touch_list, touch_item, esp_touch_item, entry);
    audio_free(touch_item);
  }
  touch_pad_deinit();
  audio_free(touch);
  return ESP_OK;
}