From b0f8b3742848106b58273fed91b1e7eab578258c Mon Sep 17 00:00:00 2001
From: Artur Gurgul <artur@gurgul.pro>
Date: Thu, 25 Sep 2025 19:22:00 +0200
Subject: [PATCH] init

---
 Cargo.toml  |  8 ++++++++
 src/main.rs | 57 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 65 insertions(+)
 create mode 100644 Cargo.toml
 create mode 100644 src/main.rs

diff --git a/Cargo.toml b/Cargo.toml
new file mode 100644
index 0000000..ff4c032
--- /dev/null
+++ b/Cargo.toml
@@ -0,0 +1,8 @@
+[package]
+name = "relay_control"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+gpio-cdev = "0.6"
+clap = { version = "4", features = ["derive"] }
diff --git a/src/main.rs b/src/main.rs
new file mode 100644
index 0000000..f9675d8
--- /dev/null
+++ b/src/main.rs
@@ -0,0 +1,57 @@
+use clap::{Parser, Subcommand};
+use gpio_cdev::{Chip, LineRequestFlags};
+use std::{thread, time::Duration};
+
+/// Banana Pi M5 relay controller (gpiochip0 line 68 = CON1-P11).
+#[derive(Parser, Debug)]
+#[command(author, version, about)]
+struct Cli {
+    #[command(subcommand)]
+    cmd: Command,
+}
+
+#[derive(Subcommand, Debug)]
+enum Command {
+    /// Turn relay ON (active-low → set line 0)
+    On,
+    /// Turn relay OFF (set line 1)
+    Off,
+    /// Pulse relay ON for N ms, then OFF
+    Pulse {
+        #[arg(long, default_value_t = 500)]
+        ms: u64,
+    },
+}
+
+fn main() -> anyhow::Result<()> {
+    let cli = Cli::parse();
+
+    // Open gpiochip0
+    let mut chip = Chip::new("/dev/gpiochip0")?;
+
+    // Request line 68 (CON1-P11) as output, default HIGH (relay OFF)
+    let handle = chip
+        .get_line(68)?
+        .request(LineRequestFlags::OUTPUT, 1, "relay_control")?;
+
+    match cli.cmd {
+        Command::On => {
+            println!("Relay ON");
+            handle.set_value(0)?;
+        }
+        Command::Off => {
+            println!("Relay OFF");
+            handle.set_value(1)?;
+        }
+        Command::Pulse { ms } => {
+            println!("Relay ON for {} ms", ms);
+            handle.set_value(0)?;
+            thread::sleep(Duration::from_millis(ms));
+            println!("Relay OFF");
+            handle.set_value(1)?;
+        }
+    }
+
+    Ok(())
+}
+ 
\ No newline at end of file