ledcat 0.1.1

Control lots of LED's over lots of protocols
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54

use std::fs;
use std::os::unix::io::AsRawFd;
use std::path;
use regex;
use device::*;
use driver;


ioctl!(write_ptr spi_ioc_wr_mode with b'k', 1; u8);
ioctl!(write_ptr spi_ioc_wr_lsb_first with b'k', 2; u8);
ioctl!(write_ptr spi_ioc_wr_max_speed_hz with b'k', 4; u32);

#[allow(dead_code)]
#[derive(Copy, Clone, Debug)]
pub enum FirstBit {
    LSB,
    MSB,
}

#[derive(Copy, Clone, Debug)]
pub struct Config {
    pub clock_polarity: u8,
    pub clock_phase: u8,
    pub first_bit: FirstBit,
    pub speed_hz: u32,
}

pub fn open(path: &path::Path, dev: &Device) -> Result<fs::File, driver::Error> {
    let spidev = fs::OpenOptions::new().write(true).open(path)?;
    let fd = spidev.as_raw_fd();

    let conf = dev.spidev_config()
        .ok_or(driver::Error::DeviceNotSupported)?;

    let lsb_first: u8 = match conf.first_bit {
        FirstBit::MSB => 0,
        FirstBit::LSB => 1,
    };
    unsafe {
        spi_ioc_wr_mode(fd, &(conf.clock_polarity | (conf.clock_polarity << 1)))?;
        spi_ioc_wr_lsb_first(fd, &lsb_first)?;
        spi_ioc_wr_max_speed_hz(fd, &conf.speed_hz)?;
    }

    Ok(spidev)
}

pub fn is_spidev(path: &path::Path) -> bool {
    let devs = regex::RegexSet::new(&[r"^/dev/spidev\d+\.\d+$",
                                      r"^/sys/devices/.+/spi\d\.\d$",
                                      r"^/sys/class/devices/.+/spi\d\.\d$"])
        .unwrap();
    devs.is_match(path.to_str().unwrap())
}