rp/gpio: implement Input

embassy-rp-examples/src/example_common.rs

@@ -0,0 +1,16 @@
+use core::sync::atomic::{AtomicUsize, Ordering};
+use defmt_rtt as _;
+use panic_probe as _;
+
+#[link_section = ".boot2"]
+#[used]
+pub static BOOT2: [u8; 256] = rp2040_boot2::BOOT_LOADER;
+
+defmt::timestamp! {"{=u64}", {
+    static COUNT: AtomicUsize = AtomicUsize::new(0);
+    // NOTE(no-CAS) `timestamps` runs with interrupts disabled
+    let n = COUNT.load(Ordering::Relaxed);
+    COUNT.store(n + 1, Ordering::Relaxed);
+    n as u64
+}
+}