setup basic file structure

kernel/src/peripherals/keyboard.rs

@@ -0,0 +1,59 @@
+use crate::peripherals::PERIPHERAL_BUS;
+pub use shared::keyboard::{KeyCode, KeyEvent, KeyState, Modifiers};
+
+const REG_ID_KEY: u8 = 0x04;
+const REG_ID_FIF: u8 = 0x09;
+
+const KEY_CAPSLOCK: u8 = 1 << 5;
+const KEY_NUMLOCK: u8 = 1 << 6;
+const KEY_COUNT_MASK: u8 = 0x1F; // 0x1F == 31
+
+pub async fn read_keyboard_fifo() -> Option<KeyEvent> {
+    let mut i2c = PERIPHERAL_BUS.get().lock().await;
+    let i2c = i2c.as_mut().unwrap();
+
+    let mut key_status = [0_u8; 1];
+
+    if i2c
+        .write_read_async(super::MCU_ADDR, [REG_ID_KEY], &mut key_status)
+        .await
+        .is_ok()
+    {
+        let _caps = key_status[0] & KEY_CAPSLOCK == KEY_CAPSLOCK;
+        let _num = key_status[0] & KEY_NUMLOCK == KEY_NUMLOCK;
+        let fifo_count = key_status[0] & KEY_COUNT_MASK;
+
+        if fifo_count >= 1 {
+            let mut event = [0_u8; 2];
+
+            if i2c
+                .write_read_async(super::MCU_ADDR, [REG_ID_FIF], &mut event)
+                .await
+                .is_ok()
+            {
+                return Some(KeyEvent {
+                    state: KeyState::from(event[0]),
+                    key: KeyCode::from(event[1]),
+                    mods: Modifiers::NONE,
+                });
+            }
+        }
+    }
+    None
+}
+
+const REG_ID_DEB: u8 = 0x06;
+const REG_ID_FRQ: u8 = 0x07;
+
+pub async fn configure_keyboard(debounce: u8, poll_freq: u8) {
+    let mut i2c = PERIPHERAL_BUS.get().lock().await;
+    let i2c = i2c.as_mut().unwrap();
+
+    let _ = i2c
+        .write_read_async(super::MCU_ADDR, [REG_ID_DEB], &mut [debounce])
+        .await;
+
+    let _ = i2c
+        .write_read_async(super::MCU_ADDR, [REG_ID_FRQ], &mut [poll_freq])
+        .await;
+}