1 files changed, 95 insertions, 0 deletions
diff --git a/src/drivers/touchwheel.cpp b/src/drivers/touchwheel.cpp
new file mode 100644
index 00000000..51a67187
--- /dev/null
+++ b/src/drivers/touchwheel.cpp
@@ -0,0 +1,95 @@
+#include "touchwheel.hpp"
+#include <stdint.h>
+
+#include <cstdint>
+
+#include "assert.h"
+#include "driver/gpio.h"
+#include "driver/i2c.h"
+#include "esp_err.h"
+#include "esp_log.h"
+#include "freertos/projdefs.h"
+#include "hal/gpio_types.h"
+#include "hal/i2c_types.h"
+
+#include "i2c.hpp"
+
+namespace drivers {
+
+static const char* kTag = "TOUCHWHEEL";
+static const uint8_t kTouchWheelAddress = 0x1C;
+static const gpio_num_t kIntPin = GPIO_NUM_25;
+
+TouchWheel::TouchWheel() {
+  gpio_config_t int_config{
+      .pin_bit_mask = 1ULL << kIntPin,
+      .mode = GPIO_MODE_INPUT,
+      .pull_up_en = GPIO_PULLUP_ENABLE,
+      .pull_down_en = GPIO_PULLDOWN_DISABLE,
+      .intr_type = GPIO_INTR_DISABLE,
+  };
+  gpio_config(&int_config);
+
+  WriteRegister(Register::RESET, 1);
+  // TODO(daniel): do we need this? how long does reset take?
+  vTaskDelay(pdMS_TO_TICKS(1));
+  WriteRegister(Register::SLIDER_OPTIONS, 0b11000000);
+  WriteRegister(Register::CALIBRATE, 1);
+}
+
+TouchWheel::~TouchWheel() {}
+
+void TouchWheel::WriteRegister(uint8_t reg, uint8_t val) {
+  // uint8_t maskedReg = reg | kWriteMask;
+  uint8_t maskedReg = reg;
+  I2CTransaction transaction;
+  transaction.start()
+      .write_addr(kTouchWheelAddress, I2C_MASTER_WRITE)
+      .write_ack(maskedReg, val)
+      .stop();
+  transaction.Execute();
+  // TODO(jacqueline): check for errors again when i find where all the ffc
+  // cables went q.q
+  // ESP_ERROR_CHECK(transaction.Execute());
+}
+
+uint8_t TouchWheel::ReadRegister(uint8_t reg) {
+  uint8_t res;
+  I2CTransaction transaction;
+  transaction.start()
+      .write_addr(kTouchWheelAddress, I2C_MASTER_WRITE)
+      .write_ack(reg)
+      .start()
+      .write_addr(kTouchWheelAddress, I2C_MASTER_READ)
+      .read(&res, I2C_MASTER_NACK)
+      .stop();
+  ESP_ERROR_CHECK(transaction.Execute());
+  return res;
+}
+
+void TouchWheel::Update() {
+  // Read data from device into member struct
+  bool has_data = !gpio_get_level(GPIO_NUM_25);
+  if (!has_data) {
+    return;
+  }
+  uint8_t status = ReadRegister(Register::DETECTION_STATUS);
+  if (status & 0b10000000) {
+    // Still calibrating.
+    return;
+  }
+  if (status & 0b10) {
+    // Slider detect.
+    data_.wheel_position = ReadRegister(Register::SLIDER_POSITION);
+  }
+  if (status & 0b1) {
+    // Key detect.
+    // TODO(daniel): implement me
+  }
+}
+
+TouchWheelData TouchWheel::GetTouchWheelData() const {
+  return data_;
+}
+
+}  // namespace drivers