dwc2: add endpoint allocation support.

[HiFiPhile]

Describe the PR Add endpoint buffer allocation support.

Also flush FIFO on bus reset, as incomplete iso transfers can cause some strange issues, seems flushing FIFO is a work around.

[HiFiPhile]

For dcd_edpt_close_all(), shouldn't it stop pending transfer and flush FIFO, just like dcd_edpt_close() does ? https://github.com/hathach/tinyusb/blob/f1898fef8c605843e1a783bf758949247caae90e/src/portable/synopsys/dwc2/dcd_dwc2.c#L632

[HiFiPhile]

Refactor done, maybe you want to apply the new coding style.

[HiFiPhile]

@kkitayam When you have time could you add ISO endpoint allocation support to UVC class ?

The idea is to avoid USB buffer alloc/free at runtime as it's hard to manage buffer on some devices.

It's pretty simple:

• Add usbd_edpt_iso_alloc in dirver opening to alloc maximum size needed: https://github.com/hathach/tinyusb/blob/67cd8349d614f7a981117ad85d6707e106cd6145/src/class/audio/audio_device.c#L1544
• In set interface, instead of usbd_edpt_close and usbd_edpt_open use usbd_edpt_iso_activate https://github.com/hathach/tinyusb/blob/67cd8349d614f7a981117ad85d6707e106cd6145/src/class/audio/audio_device.c#L1742

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Currently the main problem is in dwc2 driver, something is wrong with runtime buffer size adjustment, after ISO endpoint closing there is a chance that the device stop transferring packets.

Packets have been acked but no interrupt fired:

dwc2.zip

[HiFiPhile]

@hathach Could you take a look of my pending PRs when you have some time ? Especially this one is necessary to make audio class running reliably.

[hathach]

@hathach Could you take a look of my pending PRs when you have some time ? Especially this one is necessary to make audio class running reliably.

sorry, will review this asap.