Add CST816 touchscreen driver (#5941)

* Add CST816 touchscreen

CODEOWNERS

@@ -80,6 +80,7 @@ esphome/components/copy/* @OttoWinter
 esphome/components/cover/* @esphome/core
 esphome/components/cs5460a/* @balrog-kun
 esphome/components/cse7761/* @berfenger
+esphome/components/cst816/* @clydebarrow
 esphome/components/ct_clamp/* @jesserockz
 esphome/components/current_based/* @djwmarcx
 esphome/components/dac7678/* @NickB1

esphome/components/cst816/__init__.py

@@ -0,0 +1,6 @@
+import esphome.codegen as cg
+
+CODEOWNERS = ["@clydebarrow"]
+DEPENDENCIES = ["i2c"]
+
+cst816_ns = cg.esphome_ns.namespace("cst816")

esphome/components/cst816/binary_sensor/__init__.py

@@ -0,0 +1,28 @@
+import esphome.codegen as cg
+import esphome.config_validation as cv
+from esphome.components import binary_sensor
+
+from .. import cst816_ns
+from ..touchscreen import CST816Touchscreen, CST816ButtonListener
+
+CONF_CST816_ID = "cst816_id"
+
+CST816Button = cst816_ns.class_(
+    "CST816Button",
+    binary_sensor.BinarySensor,
+    cg.Component,
+    CST816ButtonListener,
+    cg.Parented.template(CST816Touchscreen),
+)
+
+CONFIG_SCHEMA = binary_sensor.binary_sensor_schema(CST816Button).extend(
+    {
+        cv.GenerateID(CONF_CST816_ID): cv.use_id(CST816Touchscreen),
+    }
+)
+
+
+async def to_code(config):
+    var = await binary_sensor.new_binary_sensor(config)
+    await cg.register_component(var, config)
+    await cg.register_parented(var, config[CONF_CST816_ID])

esphome/components/cst816/binary_sensor/cst816_button.h

@@ -0,0 +1,27 @@
+#pragma once
+
+#include "esphome/components/binary_sensor/binary_sensor.h"
+#include "esphome/components/cst816/touchscreen/cst816_touchscreen.h"
+#include "esphome/core/component.h"
+#include "esphome/core/helpers.h"
+
+namespace esphome {
+namespace cst816 {
+
+class CST816Button : public binary_sensor::BinarySensor,
+                     public Component,
+                     public CST816ButtonListener,
+                     public Parented<CST816Touchscreen> {
+ public:
+  void setup() override {
+    this->parent_->register_button_listener(this);
+    this->publish_initial_state(false);
+  }
+
+  void dump_config() override { LOG_BINARY_SENSOR("", "CST816 Button", this); }
+
+  void update_button(bool state) override { this->publish_state(state); }
+};
+
+}  // namespace cst816
+}  // namespace esphome

esphome/components/cst816/touchscreen/__init__.py

@@ -0,0 +1,34 @@
+import esphome.codegen as cg
+import esphome.config_validation as cv
+
+from esphome import pins
+from esphome.components import i2c, touchscreen
+from esphome.const import CONF_INTERRUPT_PIN, CONF_ID, CONF_RESET_PIN
+from .. import cst816_ns
+
+
+CST816Touchscreen = cst816_ns.class_(
+    "CST816Touchscreen",
+    touchscreen.Touchscreen,
+    i2c.I2CDevice,
+)
+
+CST816ButtonListener = cst816_ns.class_("CST816ButtonListener")
+CONFIG_SCHEMA = touchscreen.TOUCHSCREEN_SCHEMA.extend(
+    {
+        cv.GenerateID(): cv.declare_id(CST816Touchscreen),
+        cv.Optional(CONF_INTERRUPT_PIN): pins.internal_gpio_input_pin_schema,
+        cv.Optional(CONF_RESET_PIN): pins.gpio_output_pin_schema,
+    }
+).extend(i2c.i2c_device_schema(0x15))
+
+
+async def to_code(config):
+    var = cg.new_Pvariable(config[CONF_ID])
+    await touchscreen.register_touchscreen(var, config)
+    await i2c.register_i2c_device(var, config)
+
+    if interrupt_pin := config.get(CONF_INTERRUPT_PIN):
+        cg.add(var.set_interrupt_pin(await cg.gpio_pin_expression(interrupt_pin)))
+    if reset_pin := config.get(CONF_RESET_PIN):
+        cg.add(var.set_reset_pin(await cg.gpio_pin_expression(reset_pin)))

esphome/components/cst816/touchscreen/cst816_touchscreen.cpp

@@ -0,0 +1,113 @@
+#include "cst816_touchscreen.h"
+
+namespace esphome {
+namespace cst816 {
+
+void CST816Touchscreen::continue_setup_() {
+  if (this->interrupt_pin_ != nullptr) {
+    this->interrupt_pin_->setup();
+    this->attach_interrupt_(this->interrupt_pin_, gpio::INTERRUPT_FALLING_EDGE);
+  }
+  if (!this->read_byte(REG_CHIP_ID, &this->chip_id_)) {
+    this->mark_failed();
+    esph_log_e(TAG, "Failed to read chip id");
+    return;
+  }
+  switch (this->chip_id_) {
+    case CST820_CHIP_ID:
+    case CST716_CHIP_ID:
+    case CST816S_CHIP_ID:
+    case CST816D_CHIP_ID:
+    case CST816T_CHIP_ID:
+      break;
+    default:
+      this->mark_failed();
+      esph_log_e(TAG, "Unknown chip ID 0x%02X", this->chip_id_);
+      return;
+  }
+  this->write_byte(REG_IRQ_CTL, IRQ_EN_MOTION);
+  if (this->x_raw_max_ == this->x_raw_min_) {
+    this->x_raw_max_ = this->display_->get_native_width();
+  }
+  if (this->y_raw_max_ == this->y_raw_min_) {
+    this->y_raw_max_ = this->display_->get_native_height();
+  }
+  esph_log_config(TAG, "CST816 Touchscreen setup complete");
+}
+
+void CST816Touchscreen::update_button_state_(bool state) {
+  if (this->button_touched_ == state)
+    return;
+  this->button_touched_ = state;
+  for (auto *listener : this->button_listeners_)
+    listener->update_button(state);
+}
+
+void CST816Touchscreen::setup() {
+  esph_log_config(TAG, "Setting up CST816 Touchscreen...");
+  if (this->reset_pin_ != nullptr) {
+    this->reset_pin_->setup();
+    this->reset_pin_->digital_write(true);
+    delay(5);
+    this->reset_pin_->digital_write(false);
+    delay(5);
+    this->reset_pin_->digital_write(true);
+    this->set_timeout(30, [this] { this->continue_setup_(); });
+  } else {
+    this->continue_setup_();
+  }
+}
+
+void CST816Touchscreen::update_touches() {
+  uint8_t data[13];
+  if (!this->read_bytes(REG_STATUS, data, sizeof data)) {
+    this->status_set_warning();
+    return;
+  }
+  uint8_t num_of_touches = data[REG_TOUCH_NUM] & 3;
+  if (num_of_touches == 0) {
+    this->update_button_state_(false);
+    return;
+  }
+
+  uint16_t x = encode_uint16(data[REG_XPOS_HIGH] & 0xF, data[REG_XPOS_LOW]);
+  uint16_t y = encode_uint16(data[REG_YPOS_HIGH] & 0xF, data[REG_YPOS_LOW]);
+  esph_log_v(TAG, "Read touch %d/%d", x, y);
+  if (x >= this->x_raw_max_) {
+    this->update_button_state_(true);
+  } else {
+    this->add_raw_touch_position_(0, x, y);
+  }
+}
+
+void CST816Touchscreen::dump_config() {
+  ESP_LOGCONFIG(TAG, "CST816 Touchscreen:");
+  LOG_I2C_DEVICE(this);
+  LOG_PIN("  Interrupt Pin: ", this->interrupt_pin_);
+  LOG_PIN("  Reset Pin: ", this->reset_pin_);
+  const char *name;
+  switch (this->chip_id_) {
+    case CST820_CHIP_ID:
+      name = "CST820";
+      break;
+    case CST816S_CHIP_ID:
+      name = "CST816S";
+      break;
+    case CST816D_CHIP_ID:
+      name = "CST816D";
+      break;
+    case CST716_CHIP_ID:
+      name = "CST716";
+      break;
+    case CST816T_CHIP_ID:
+      name = "CST816T";
+      break;
+    default:
+      name = "Unknown";
+      break;
+  }
+  ESP_LOGCONFIG(TAG, "  Chip type: %s", name);
+}
+
+}  // namespace cst816
+}  // namespace esphome

esphome/components/cst816/touchscreen/cst816_touchscreen.h

@@ -0,0 +1,60 @@
+#pragma once
+
+#include "esphome/components/i2c/i2c.h"
+#include "esphome/components/touchscreen/touchscreen.h"
+#include "esphome/core/component.h"
+#include "esphome/core/hal.h"
+#include "esphome/core/log.h"
+
+namespace esphome {
+namespace cst816 {
+
+static const char *const TAG = "cst816.touchscreen";
+
+static const uint8_t REG_STATUS = 0x00;
+static const uint8_t REG_TOUCH_NUM = 0x02;
+static const uint8_t REG_XPOS_HIGH = 0x03;
+static const uint8_t REG_XPOS_LOW = 0x04;
+static const uint8_t REG_YPOS_HIGH = 0x05;
+static const uint8_t REG_YPOS_LOW = 0x06;
+static const uint8_t REG_DIS_AUTOSLEEP = 0xFE;
+static const uint8_t REG_CHIP_ID = 0xA7;
+static const uint8_t REG_FW_VERSION = 0xA9;
+static const uint8_t REG_SLEEP = 0xE5;
+static const uint8_t REG_IRQ_CTL = 0xFA;
+static const uint8_t IRQ_EN_MOTION = 0x70;
+
+static const uint8_t CST820_CHIP_ID = 0xB7;
+static const uint8_t CST816S_CHIP_ID = 0xB4;
+static const uint8_t CST816D_CHIP_ID = 0xB6;
+static const uint8_t CST816T_CHIP_ID = 0xB5;
+static const uint8_t CST716_CHIP_ID = 0x20;
+
+class CST816ButtonListener {
+ public:
+  virtual void update_button(bool state) = 0;
+};
+
+class CST816Touchscreen : public touchscreen::Touchscreen, public i2c::I2CDevice {
+ public:
+  void setup() override;
+  void update_touches() override;
+  void register_button_listener(CST816ButtonListener *listener) { this->button_listeners_.push_back(listener); }
+  void dump_config() override;
+
+  void set_interrupt_pin(InternalGPIOPin *pin) { this->interrupt_pin_ = pin; }
+  void set_reset_pin(GPIOPin *pin) { this->reset_pin_ = pin; }
+
+ protected:
+  void continue_setup_();
+  void update_button_state_(bool state);
+
+  InternalGPIOPin *interrupt_pin_{};
+  GPIOPin *reset_pin_{};
+  uint8_t chip_id_{};
+  std::vector<CST816ButtonListener *> button_listeners_;
+  bool button_touched_{};
+};
+
+}  // namespace cst816
+}  // namespace esphome

tests/components/cst816/test.esp32.yaml

@@ -0,0 +1,36 @@
+touchscreen:
+  - platform: cst816
+    id: my_touchscreen
+    interrupt_pin:
+      number: 21
+    reset_pin: GPIO16
+    transform:
+      mirror_x: false
+      mirror_y: false
+      swap_xy: false
+
+i2c:
+  sda: 3
+  scl: 2
+
+display:
+  - id: my_display
+    platform: ili9xxx
+    dimensions: 480x320
+    model: ST7796
+    cs_pin: 15
+    dc_pin: 20
+    reset_pin: 22
+    transform:
+      swap_xy: true
+      mirror_x: true
+      mirror_y: true
+    auto_clear_enabled: false
+
+spi:
+  clk_pin: 14
+  mosi_pin: 13
+
+binary_sensor:
+  - platform: cst816
+    name: Home Button