2 files changed, 61 insertions, 1 deletions
diff --git a/src/drivers/include/i2c.hpp b/src/drivers/include/i2c.hpp
index dbdd8a11..811c9333 100644
--- a/src/drivers/include/i2c.hpp
+++ b/src/drivers/include/i2c.hpp
@@ -35,7 +35,7 @@ class I2CTransaction {
    * ESP_ERR_INVALID_STATE I2C driver not installed or not in master mode.
    * ESP_ERR_TIMEOUT Operation timeout because the bus is busy.
    */
-  esp_err_t Execute();
+  esp_err_t Execute(uint8_t port = I2C_NUM_0);
 
   /*
    * Enqueues a start condition. May also be used for repeated start
diff --git a/src/drivers/include/touchwheel.hpp b/src/drivers/include/touchwheel.hpp
new file mode 100644
index 00000000..14215acd
--- /dev/null
+++ b/src/drivers/include/touchwheel.hpp
@@ -0,0 +1,60 @@
+#pragma once
+
+
+#include <functional>
+#include <stdint.h>
+
+#include "esp_err.h"
+#include "result.hpp"
+
+#include "gpio_expander.hpp"
+
+namespace drivers {
+
+struct TouchWheelData {
+  bool is_touched = false;
+  uint8_t wheel_position = -1;
+};
+
+class TouchWheel {
+ public:
+  enum Error {
+    FAILED_TO_BOOT,
+    FAILED_TO_CONFIGURE,
+  };
+  static auto create(GpioExpander* expander)
+      -> cpp::result<std::unique_ptr<TouchWheel>, Error>;
+
+  TouchWheel(GpioExpander* gpio);
+  ~TouchWheel();
+
+  // Not copyable or movable.
+  TouchWheel(const TouchWheel&) = delete;
+  TouchWheel& operator=(const TouchWheel&) = delete;
+
+  auto Update() -> void;
+  auto GetTouchWheelData() const -> TouchWheelData;
+
+ private:
+  GpioExpander* gpio_;
+  TouchWheelData data_;
+  
+  enum Register {
+    FIRMWARE_VERSION = 0x1,
+    DETECTION_STATUS = 0x2,
+    KEY_STATUS_A     = 0x3,
+    KEY_STATUS_B     = 0x4,
+    SLIDER_POSITION  = 0x5,
+    CALIBRATE        = 0x6,
+    RESET            = 0x7,
+    LOW_POWER        = 0x8,
+    SLIDER_OPTIONS   = 0x14,
+  };
+
+
+  void WriteRegister(uint8_t reg, uint8_t val);
+  void ReadRegister(uint8_t reg, uint8_t* data, uint8_t count);
+
+};
+
+}  // namespace drivers