mbox series

[v11,0/2] usb: xhci: Add Clear_TT_Buffer

Message ID 1559559224-9845-1-git-send-email-jilin@nvidia.com (mailing list archive)
Headers show
Series usb: xhci: Add Clear_TT_Buffer | expand

Message

Jim Lin June 3, 2019, 10:53 a.m. UTC
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.
 
Signed-off-by: Jim Lin <jilin@nvidia.com>

Jim Lin (2):
  usb: Add devaddr in struct usb_device
  usb: xhci: Add Clear_TT_Buffer

 drivers/usb/core/hub.c       |  4 +++-
 drivers/usb/host/xhci-ring.c | 27 ++++++++++++++++++++++++++-
 drivers/usb/host/xhci.c      | 23 +++++++++++++++++++++++
 drivers/usb/host/xhci.h      |  5 +++++
 include/linux/usb.h          |  2 ++
 5 files changed, 59 insertions(+), 2 deletions(-)

Comments

Greg KH June 3, 2019, 12:23 p.m. UTC | #1
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?

> Signed-off-by: Jim Lin <jilin@nvidia.com>

There is nothing to sign off on a 0/X patch :)

thanks,

greg k-h
Jim Lin June 4, 2019, 8:53 a.m. UTC | #2
On 2019年06月03日 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
Greg KH June 4, 2019, 8:59 a.m. UTC | #3
On Tue, Jun 04, 2019 at 04:53:54PM +0800, Jim Lin wrote:
> 
> 
> On 2019年06月03日 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.

Please do, only resend if you do not get a response after 2 weeks.

thanks,

greg k-h
Alan Stern June 4, 2019, 2:22 p.m. UTC | #4
On Tue, 4 Jun 2019, Jim Lin wrote:

> On 2019年06月03日 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?

Did I not do this already?  Oh well, in any case:

Acked-by: Alan Stern <stern@rowland.harvard.edu>

Alan Stern