Hack in support for other boards/microcontrollers, add GpioDriver

There's definitely plenty of cleanup work to be done (see:
"ifdefs").

firmware/Bsp/Drivers/GpioDriver.h

@@ -0,0 +1,101 @@
+/*
+ * Copyright (C) 2019  Max Regan
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#pragma once
+
+#include "Bsp/ReturnCode.h"
+#include "Bsp/TaskScheduler.h"
+
+#include "Mcu.h"
+
+namespace BSP {
+
+class GpioDriver {
+public:
+    GpioDriver(GPIO_TypeDef *gpio);
+
+    void init();
+    void enable();
+    void disable();
+
+    enum class output_mode_t {
+        PUSH_PULL,
+        OPEN_DRAIN,
+    };
+
+    enum class output_speed_t {
+        LOW,
+        MEDIUM,
+        HIGH,
+        VERY_HIGH,
+    };
+
+    enum class input_pull_t {
+        FLOATING,
+        PULL_UP,
+        PULL_DOWN,
+    };
+
+    friend class GpioPin;
+
+private:
+
+    enum class moder_t {
+        INPUT,
+        OUTPUT,
+        ALTERNATE_FUNCTION,
+    };
+
+    void set_pin_moder(uint32_t index, moder_t mode);
+    void set_pin_pupdr(uint32_t index, input_pull_t pull_mode);
+    void set_pin_otyper(uint32_t index, output_mode_t mode);
+    void set_pin_ospeedr(uint32_t index, output_speed_t speed);
+
+    void configure_pin_input(uint32_t index, input_pull_t pull_mode);
+    void configure_pin_output(uint32_t index, output_mode_t mode, output_speed_t speed);
+    void configure_pin_alternate_function(uint32_t index, uint32_t function);
+
+    void write_pin(uint32_t index, bool value);
+    bool read_pin(uint32_t index);
+
+    GPIO_TypeDef * const m_gpio;
+};
+
+class GpioPin {
+public:
+    GpioPin(GpioDriver &m_driver, uint32_t index);
+
+    void configure_input(GpioDriver::input_pull_t pull_mode);
+    void configure_output(GpioDriver::output_mode_t mode, GpioDriver::output_speed_t speed);
+    void configure_alternate_function(uint32_t function);
+
+    void write(bool value);
+    bool read();
+
+    GpioDriver &get_driver();
+    uint32_t get_index();
+
+private:
+    GpioDriver &m_gpio;
+    uint32_t const m_index;
+};
+
+}