Re: [Qemu-trivial] [PATCH] ohci: set effectively usb frame rate to 1kHz

[Gerd Hoffmann]

On Thu, Sep 27, 2018 at 05:19:36PM +0200, Miguel GAIO wrote:
> USB frame rate is slightly lower than 1kHz: ie. ~950Hz.
> Thus usb-audio device is not able to perform a simple audio playback
> without underruns on audio backend.
> eg. "-device pci-ohci,id=ohci -device usb-audio,bus=ohci.0" vs PulseAudio
> backend. more than 50 underruns are observed per second.
> 
> Update ohci_sof_time computation, using QEMU_CLOCK_VIRTUAL in
> ohci_usb_start(), and increment by usb_frame_time in ohci_sof()
> makes USB frame rate close to 1kHz.
> This way, no audio underrun are observed during audio playback.

Added to usb patch queue.

thanks,
  Gerd