Add mozc double sided version.

Change-Id: I3c50b5c3435c3c01c79bfc14c5d605701a423356
Co-authored-by: Takashi Toyoshima <toyoshim@google.com>
Co-authored-by: Shun Ikejima <ikejima@google.com>
Reviewed-by: Eliot Courtney <edcourtney@google.com>

mozc-doublesided/firmware/Core/Inc/hid.h

@@ -0,0 +1,14 @@
+// Copyright 2024 Google Inc.
+// Use of this source code is governed by an Apache License that can be found in
+// the LICENSE file.
+
+#ifndef HID_H_
+#define HID_H_
+
+#include <stdint.h>
+
+void hid_init(void);
+void hid_update(const uint8_t* keys);
+void hid_deinit(void);
+
+#endif  // HID_H_

mozc-doublesided/firmware/Core/Inc/i2c.h

@@ -0,0 +1,15 @@
+// Copyright 2024 Google Inc.
+// Use of this source code is governed by an Apache License that can be found in
+// the LICENSE file.
+
+#ifndef I2C_H_
+#define I2C_H_
+
+#include <stdbool.h>
+
+void i2c_init(void);
+bool i2c_is_host(void);
+void i2c_activate_host(void);
+void i2c_maybe_listen(void);
+
+#endif  // I2C_H_

mozc-doublesided/firmware/Core/Inc/led.h

@@ -0,0 +1,13 @@
+// Copyright 2024 Google Inc.
+// Use of this source code is governed by an Apache License that can be found in
+// the LICENSE file.
+
+#ifndef LED_H_
+#define LED_H_
+
+#include <stdint.h>
+
+void led_set(uint8_t index, uint8_t r, uint8_t g, uint8_t b);
+void led_flush(void);
+
+#endif  // LED_H_

mozc-doublesided/firmware/Core/Inc/mozc.h

@@ -0,0 +1,11 @@
+// Copyright 2024 Google Inc.
+// Use of this source code is governed by an Apache License that can be found in
+// the LICENSE file.
+
+#ifndef MOZC_H_
+#define MOZC_H_
+
+void mozc_init(void);
+void mozc_loop(void);
+
+#endif  // MOZC_H_