Trait Handler

pub trait Handler {
    // Provided methods
    fn enabled(&mut self, _enabled: bool) { ... }
    fn reset(&mut self) { ... }
    fn addressed(&mut self, _addr: u8) { ... }
    fn configured(&mut self, _configured: bool) { ... }
    fn suspended(&mut self, _suspended: bool) { ... }
    fn remote_wakeup_enabled(&mut self, _enabled: bool) { ... }
    fn set_alternate_setting(
        &mut self,
        iface: InterfaceNumber,
        alternate_setting: u8,
    ) { ... }
    fn control_out(&mut self, req: Request, data: &[u8]) -> Option<OutResponse> { ... }
    fn control_in<'a>(
        &'a mut self,
        req: Request,
        buf: &'a mut [u8],
    ) -> Option<InResponse<'a>> { ... }
    fn get_string(&mut self, index: StringIndex, lang_id: u16) -> Option<&str> { ... }
}

Handler for device events and control requests.

All methods are optional callbacks that will be called by UsbDevice::run()

Provided Methods

fn enabled(&mut self, _enabled: bool)

Called when the USB device has been enabled or disabled.

fn reset(&mut self)

Called after a USB reset after the bus reset sequence is complete.

fn addressed(&mut self, _addr: u8)

Called when the host has set the address of the device to addr.

fn configured(&mut self, _configured: bool)

Called when the host has enabled or disabled the configuration of the device.

fn suspended(&mut self, _suspended: bool)

Called when the bus has entered or exited the suspend state.

fn remote_wakeup_enabled(&mut self, _enabled: bool)

Called when remote wakeup feature is enabled or disabled.

fn set_alternate_setting( &mut self, iface: InterfaceNumber, alternate_setting: u8, )

Called when a “set alternate setting” control request is done on the interface.

fn control_out(&mut self, req: Request, data: &[u8]) -> Option<OutResponse>

Called when a control request is received with direction HostToDevice.

Arguments

• req - The request from the SETUP packet.
• data - The data from the request.

Returns

If you didn’t handle this request (for example if it’s for the wrong interface), return None. In this case, the the USB stack will continue calling the other handlers, to see if another handles it.

If you did, return Some with either Accepted or Rejected. This will make the USB stack respond to the control request, and stop calling other handlers.

fn control_in<'a>( &'a mut self, req: Request, buf: &'a mut [u8], ) -> Option<InResponse<'a>>

Called when a control request is received with direction DeviceToHost.

You should write the response somewhere (usually to buf, but you may use another buffer owned by yourself, or a static buffer), then return InResponse::Accepted(data).

Arguments

• req - The request from the SETUP packet.

Returns

If you didn’t handle this request (for example if it’s for the wrong interface), return None. In this case, the the USB stack will continue calling the other handlers, to see if another handles it.

If you did, return Some with either Accepted or Rejected. This will make the USB stack respond to the control request, and stop calling other handlers.

fn get_string(&mut self, index: StringIndex, lang_id: u16) -> Option<&str>

Called when a GET_DESCRIPTOR STRING control request is received.

Implementors