1 // Copyright (c) 2018 The rust-gpio-cdev Project Developers.
2 //
3 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
4 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
5 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
6 // option. This file may not be copied, modified, or distributed
7 // except according to those terms.
8
9 use gpio_cdev::{Chip, EventRequestFlags, EventType, LineRequestFlags};
10 use quicli::prelude::*;
11 use std::thread::sleep;
12 use std::time::Duration;
13 use structopt::StructOpt;
14
15 #[derive(Debug, StructOpt)]
16 struct Cli {
17 /// The gpiochip device (e.g. /dev/gpiochip0)
18 chip: String,
19 /// The offset of the GPIO input line for the provided chip
20 inputline: u32,
21 /// The offset of the GPIO output line for the provided chip
22 outputline: u32,
23 /// Sleep time after each actuation in milliseconds
24 sleeptime: u64,
25 }
26
do_main(args: Cli) -> std::result::Result<(), gpio_cdev::Error>27 fn do_main(args: Cli) -> std::result::Result<(), gpio_cdev::Error> {
28 let mut chip = Chip::new(args.chip)?;
29 let input = chip.get_line(args.inputline)?;
30 let output = chip.get_line(args.outputline)?;
31 let output_handle = output.request(LineRequestFlags::OUTPUT, 0, "tit_for_tat")?;
32
33 // To show off the buffering characteristics of the new interface we introduce a delay
34 // after each change is handled. When we fall behind, we will "replay" the input
35 // events
36 for event in input.events(
37 LineRequestFlags::INPUT,
38 EventRequestFlags::BOTH_EDGES,
39 "tit_for_tat",
40 )? {
41 let evt = event?;
42 println!("{:?}", evt);
43 match evt.event_type() {
44 EventType::RisingEdge => {
45 output_handle.set_value(1)?;
46 sleep(Duration::from_millis(args.sleeptime));
47 }
48 EventType::FallingEdge => {
49 output_handle.set_value(0)?;
50 sleep(Duration::from_millis(args.sleeptime));
51 }
52 }
53 }
54
55 Ok(())
56 }
57
main() -> CliResult58 fn main() -> CliResult {
59 let args = Cli::from_args();
60 do_main(args).or_else(|e| {
61 error!("{:?}", e);
62 Ok(())
63 })
64 }
65