dwc2/host: enable disconnect interrupt + handle it

[maximevince]

Describe the PR
On boards using the Synopsys DWC2 USB IP core, there were no disconnection events when a USB device was unplugged.
This PR enabled the GINTSTS_DISCINT flag, to get an interrupt on disconnection + handles it by calling hcd_event_device_remove().

Additional context
Tested on an STM32F7, but behavior should be identical on any device using the dwc2

[HiFiPhile]

Hi, I ended up with the same thing in #2960

I also removed hcd_event_device_remove(rhport, in_isr); from handle_hprt_irq() to prevent double remove event in some cases.

[maximevince]

Aha, nice!
Do you want me to remove hcd_event_device_remove in handle_hprt_irq as well, and merge this PR first?

It doesn't matter to me, whichever you can get merged first :)

[HiFiPhile]

Do you want me to remove hcd_event_device_remove in handle_hprt_irq as well

Yes please, just double checked ST's HAL code.

and merge this PR first ?

@hathach is busy atm, since dwc2 is widely used it's better wait for Espressif @roma-jam for a double check.
Personally I tested with ESP32-S3-DevKitM and NUCLEO-H7S3L8.

---

Out of topic: Have you experienced any bouncing issue doing quickly connection/disconnection like in #2960 ?

[maximevince]

@HiFiPhile

• I've updated the PR. I have also removed hcd_event_device_remove(rhport, in_isr); from handle_hprt_irq() now
• About the "bouncing": if I manually connect/disconnect very quickly, the USB port crashes indeed.
  It crashes in usbh.c in function process_enumeration() in case ENUM_ADDR0_DEVICE_DESC:

  TU_ASSERT(tuh_descriptor_get_device(addr0, _usbh_epbuf.ctrl, 8,
                                      process_enumeration, ENUM_SET_ADDR),);

  or in: hcd_dwc2.c, function hcd_edpt_xfer() at line 638:

  uint8_t ep_id = edpt_find_opened(dev_addr, ep_num, ep_dir);
  TU_ASSERT(ep_id < CFG_TUH_DWC2_ENDPOINT_MAX);

[maximevince]

Can we merge this? Is there any more action required from my side?
@hathach @HiFiPhile

[HiFiPhile]

It's reliable in my end, @hathach do you need more test ?

[hathach]

perfect, thank you