From: Dinh Nguyen <dingu...@opensource.altera.com>

Hi Ming-Lei,

Thanks for your patch to enable the URB giveback in a tasklet context for
the EHCI driver. I found your patch to fix a USB webcam timeout/stutter
issue on the DWC2 HCD in the SOCFPGA platform.

However, I need your help trying to figure out why I need the 2nd patch to
get your URB giveback patch to fully work.

I enable tracepoints in the dwc2 dwc2_handle_hcd_intr for irq:irq_handler_entry
and irq:irq_handler_exit. However, I did not see any measurable differences
between enabling HCD_BH and no enabling HCD_BH. But I am able to get a full
image from a webcam with the following 2 patches, and timeouts/green screen
without the 2 patches.

I am using a Logitech HD C270 webcam.

Opening video decoder: [raw] RAW Uncompressed Video
Movie-Aspect is undefined - no prescaling applied.
VO: [sdl] 640x480 => 640x480 Packed YUY2 
Selected video codec: [rawyuy2] vfm: raw (RAW YUY2)

Can you provide any comments on the following issues:

1) Am I placing the tracepoints in the right place for this non-ehci hcd?
2) I don't quite understand why removing local_irq_save/local_irq_restore
   around the the complete makes the webcam work?

Thanks in advance for your comments.

Dinh



Dinh Nguyen (2):
  usb: dwc2: Enable HCD_BH in the dwc2 driver
  usb-core: Remove the local_irq_save/local_irq_restore around complete

 drivers/usb/core/hcd.c | 2 --
 drivers/usb/dwc2/hcd.c | 6 +-----
 2 files changed, 1 insertion(+), 7 deletions(-)

-- 
2.0.3

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