sdmmc: add DeviceDetector, gpio: implement client api

libraries/libvapours/include/vapours/device_code.hpp

@@ -0,0 +1,49 @@
+/*
+ * Copyright (c) 2018-2020 Atmosphère-NX
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+#include <vapours/common.hpp>
+#include <vapours/assert.hpp>
+
+namespace ams {
+
+    namespace impl {
+
+        using DeviceCodeType = u32;
+
+    }
+
+    /* TODO: Better understand device code components. */
+    class DeviceCode {
+        private:
+            impl::DeviceCodeType inner_value;
+        public:
+            constexpr DeviceCode(impl::DeviceCodeType v) : inner_value(v) { /* ... */ }
+
+            constexpr impl::DeviceCodeType GetInternalValue() const { return this->inner_value; }
+
+            constexpr bool operator==(const DeviceCode &rhs) const {
+                return this->GetInternalValue() == rhs.GetInternalValue();
+            }
+
+            constexpr bool operator!=(const DeviceCode &rhs) const {
+                return !(*this == rhs);
+            }
+    };
+
+    constexpr inline const DeviceCode InvalidDeviceCode(0);
+
+}