Darian Leung ff4e4f4c80 hal: Fix USB DWC HAL host channel halt race condition ...

This commit fixes a race condtion bug with usb_dwc_hal_chan_request_halt()
where a channel the channel is halted if it has just completed a transfer
(i.e., finished processing a QTD with the "HOC" flag set) but the channel is
still pending interrupt handling. In this case...

- usb_dwc_hal_chan_request_halt() would simply read the channel's underlying
register, determine it is not active, not set the "halt_requested" flag, and
simply return true.
- The caller assumes of usb_dwc_hal_chan_request_halt() will assume that the
channel has halted, and may proceed to reconfigure the pipe/port
- When usb_dwc_hal_chan_decode_intr() comes to process the pending interrupt
it will simply return USB_DWC_HAL_CHAN_EVENT_CPLT not knowing a halt has been
requested.

This commit updates the implementation of usb_dwc_hal_chan_request_halt() so
that a halt is properly requested even if the underlying channel has already
physically halted.

2023-01-09 17:55:48 +08:00

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