state() needs box software 0.29.0 or newer. Older boxes reject the action, and
the crate turns that specific rejection into Error::UnsupportedByBox with the
message
the 'state' action on /usb/command requires box software >= 0.29.0; update the box or use toggle/enable/disable.
Power the port off, wait, and power it on again. The box watches for the device to
re-enumerate. It requires box software 0.39.0 or later.
match port.cycle()? { Some(true) => println!("the DUT came back"), Some(false) => panic!("the DUT did not re-enumerate"), None => println!("the port was empty, or the hub cannot watch for the device"),}
The port is powered at the end on every path, including failures. The default off
time is 1 s. cycle_with_off_time(secs) takes another value from 0.5 to 10 s. When in
doubt, choose a longer time: a short one lets the DUT warm-start without a real reset.
Like cycle(), and the report also carries the box’s outcome (box 0.49.0 or later).
A UsbCycleReport has three fields: reconnected, the same value that cycle() returns;
outcome; and the box’s message.
The outcome tells an empty port apart from a port the box did not watch:
UsbCycleOutcome
Meaning
Reconnected
The device re-enumerated after power returned
NotReconnected
The device did not come back before the box’s timeout
NoDevice
Nothing on the port was on the bus when the cycle started
Force a DUT to re-enumerate and wait for it to come back
use lager::{LagerBox, UsbDeviceFilter};use std::time::{Duration, Instant};let lager = LagerBox::from_env()?;let port = lager.usb("usb3");port.disable()?;std::thread::sleep(Duration::from_millis(500));port.enable()?;// Poll the bus until the DUT reappears. usb_devices() is cheap and takes no// exclusive access, so this loop is safe.let filter = UsbDeviceFilter { vid: Some("0483".into()), ..Default::default() };let deadline = Instant::now() + Duration::from_secs(10);loop { if !lager.usb_devices_matching(&filter)?.is_empty() { break; } assert!(Instant::now() < deadline, "DUT did not re-enumerate"); std::thread::sleep(Duration::from_millis(200));}
On a Plugable dock, a device on a powered-off port stays listed on the bus until
power returns. The loop above can then match the old entry at once, before the DUT
re-enumerates. Use cycle() instead, which waits for the hub to report the
reconnect.
