Audio System + Drivers (#562)

Drivers/aw9523b-module/include/drivers/aw9523b.h

@@ -0,0 +1,26 @@
+// SPDX-License-Identifier: Apache-2.0
+#pragma once
+
+#include <stdint.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * @brief AW9523B GPIO expander device configuration.
+ *
+ * 16 pins total: P0_0..P0_7 map to GpioDescriptor pin numbers 0..7, P1_0..P1_7
+ * map to pin numbers 8..15. P0 defaults to open-drain per hardware reset; this
+ * driver switches P0 to push-pull mode on start (matches every known board's
+ * usage of this chip, since open-drain P0 cannot drive an active-high output
+ * without an external pull-up).
+ */
+struct Aw9523bConfig {
+    /** I2C address on the bus (typically 0x58) */
+    uint8_t address;
+};
+
+#ifdef __cplusplus
+}
+#endif