Add HAL GPIO pin implementation

include/sta/hal/gpio_pin.hpp

@@ -0,0 +1,45 @@
+/**
+ * @brief Wrapper for HAL GPIO pins.
+ *
+ * Defined STA_HAL_GPIO_ENABLE in <sta/config.hpp> to enable.
+ */
+#ifndef STA_HAL_GPIO_PIN_HPP
+#define STA_HAL_GPIO_PIN_HPP
+
+#include <sta/config.hpp>
+#ifdef STA_HAL_GPIO_ENABLE
+
+#include <sta/gpio_pin.hpp>
+
+#include <main.h>
+
+
+namespace sta
+{
+	/**
+	 * @brief Container for HAL GPIO Pin objects.
+	 */
+	class HalGpioPin : public GpioPin
+	{
+	public:
+		HalGpioPin(GPIO_TypeDef * port, uint16_t pin);
+
+		void setState(GpioPinState state) override;
+
+	private:
+		GPIO_TypeDef * port_;   /**< GPIO port */
+		uint16_t pin_;          /**< GPIO pin */
+	};
+}
+
+/**
+ * @brief Create HalGpioPin object from pin label.
+ *
+ * @param label     Pin label
+ */
+#define STA_HAL_GPIO_PIN(label) sta::HalGpioPin{label##_GPIO_Port, label##_Pin}
+
+
+#endif // STA_HAL_GPIO_ENABLE
+
+#endif // STA_HAL_GPIO_PIN_HPP