Don't work when MIDI Device re-plug

[oujianshen]

This is a great project, I can run it and all the functions are normal

When the MIDI Device is reinserted, it cannot be automatically recognized and needs to be restarted to function properly again
I see that the new device is defined in the function in usbhelp.hpp as void _cliend_event_callback (const usbhost_cliend_event_msg_t * event_msg, void * arg)
I guess this function was not called during the second insertion But my ability is limited and I can't change this code well Who can help fix this issue of reinsertion and rediscovery?
Thank you very much

[fastfourier666]

I made a hackjob fix here

The original does not do any cleanup when the device is unplugged - either in the sketch or the ESP USB Host library. I added a callback so usbhelp.hpp can call a function in the main sketch when the device is "gone".

I'm sure it is pretty janky, would love to hear some improvements. I know next to nothing about USB. Cheers.

[qa2080639]

~~ I spent a whole day looking for this problem and finally found the reason.

use usb_host_interface_release,usb_host_device_close can fix it
example code usbhhelp.hpp

case USB_HOST_CLIENT_EVENT_DEV_GONE:
    ESP_LOGI("", "Device Gone handle: %x", event_msg->dev_gone.dev_hdl);
    err = usb_host_interface_release(Client_Handle, event_msg->dev_gone.dev_hdl, 0);
    if (err != ESP_OK)
      ESP_LOGI("", "usb_host_interface_release: %x", err);
    err = usb_host_device_close(Client_Handle, event_msg->dev_gone.dev_hdl);
    if (err != ESP_OK)
      ESP_LOGI("", "usb_host_device_close: %x", err);
    break;

[01GOD]

case USB_HOST_CLIENT_EVENT_DEV_GONE:
ESP_LOGI("", "Device Gone handle: %x", event_msg->dev_gone.dev_hdl);
err = usb_host_interface_release(Client_Handle, event_msg->dev_gone.dev_hdl, 0);
if (err != ESP_OK)
ESP_LOGI("", "usb_host_interface_release: %x", err);
err = usb_host_device_close(Client_Handle, event_msg->dev_gone.dev_hdl);
if (err != ESP_OK)
ESP_LOGI("", "usb_host_device_close: %x", err);
break;

Can explain how? I tried it and I know of a skilled embedded engineer that also tried it.

When I flashed an ESP32-S3 dev kit clone with that in verbose mode, it simply flashes it and the transmit LED turns on, but no serial monitor messages sadly.

Recommended solutions? Thanks in advance!

[EParisot]

@fastfourier666 You did a great job thank you for sharing !