Re: [PATCH v11 0/2] usb: xhci: Add Clear_TT_Buffer

[Jim Lin]

On 2019å06æ03æ 20:23, Greg KH wrote:
> On Mon, Jun 03, 2019 at 06:53:42PM +0800, Jim Lin wrote:
> > USB 2.0 specification chapter 11.17.5 says "as part of endpoint halt
> > processing for full-/low-speed endpoints connected via a TT, the host
> > software must use the Clear_TT_Buffer request to the TT to ensure
> > that the buffer is not in the busy state".
> >
> > In our case, a full-speed speaker (ConferenceCam) is behind a high-
> > speed hub (ConferenceCam Connect), sometimes once we get STALL on a
> > request we may continue to get STALL with the folllowing requests,
> > like Set_Interface.
> >
> > Solution is to invoke usb_hub_clear_tt_buffer() to send
> > Clear_TT_Buffer request to the hub of the device for the following
> > Set_Interface requests to the device to get ACK successfully.
> >
> > The Clear_TT_Buffer request sent to the hub includes the address of
> > the LS/FS child device in wValue field. usb_hub_clear_tt_buffer()
> > uses udev->devnum to set the address wValue. This won't work for
> > devices connected to xHC.
> >
> > For other host controllers udev->devnum is the same as the address of
> > the usb device, chosen and set by usb core. With xHC the controller
> > hardware assigns the address, and won't be the same as devnum.
> >
> > Here we have two patches.
> > One is to add devaddr in struct usb_device for
> > usb_hub_clear_tt_buffer() to use.
> > Another is to invoke usb_hub_clear_tt_buffer() for halt processing.
> Why did you resend patch series 11?
Didn't get response in 2 or 3 days.
Will be more patient next time.

May I get patch v11 1/2 acked or reviewed by Alan?

Thanks,
Jim