touch_gt911.h

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#pragma once
 
#include "roo_display/core/device.h"
#include "roo_display/driver/common/basic_touch.h"
#include "roo_display/driver/common/gpio_setter.h"
#include "roo_display/hal/i2c.h"
#include "roo_threads.h"
#include "roo_threads/atomic.h"
#include "roo_threads/thread.h"
 
namespace roo_display {
 
// Note: this driver doesn't support interrupt-driven read explicitly. You can
// still use interrupts, if you want to, by registering an interrupt handler on
// the pinIntr pin externally, and then reacting to the interrupt signal by
// calling readTouch().
//
// Even if you're not using interrupts, you should still provide the pinIntr to
// the driver - or, alternatively, pull it low (e.g. tie it to GND). This is
// necessary because the GT911 uses the pin to select between two I2C addresses
// during initialization. This driver always uses the 0x5D address, which is
// selected by pulling the pin low during reset.
class TouchGt911 : public BasicTouchDevice<5> {
 public:
  // Constructs the driver assuming the default I2C bus.
  // For GpioSetter, you can pass pin numbers, or a custom implementation.
  TouchGt911(GpioSetter pinIntr, GpioSetter pinRst, long reset_low_hold_ms = 1);
 
  // Constructs the driver using the specified I2C bus (passed as the first
  // argument).
  // When using Arduino, you can pass a Wire& object reference.
  // When using esp-idf, you can pass an i2c_port_num_t.
  // For GpioSetter, you can pass pin numbers, or a custom implementation.
  TouchGt911(I2cMasterBusHandle i2c, GpioSetter pinIntr, GpioSetter pinRst,
             long reset_low_hold_ms = 1);
 
  // Initializes the driver (performing GPIO setup and calling reset()).
  // Must be called once.
  void initTouch() override;
 
  int readTouch(TouchPoint* point) override;
 
  void reset();
 
 private:
  bool readByte(uint16_t reg, roo::byte& result);
  void writeByte(uint16_t reg, roo::byte val);
  void readBlock(roo::byte* buf, uint16_t reg, uint8_t size);
 
  int8_t addr_;
  GpioSetter pinIntr_;
  GpioSetter pinRst_;
  I2cSlaveDevice i2c_slave_;
  long reset_low_hold_ms_;
 
  roo::atomic<bool> ready_;
  roo::thread reset_thread_;
};
 
}  // namespace roo_display