| Message ID | 1557491070-24715-3-git-send-email-jilin@nvidia.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | usb: xhci: Add Clear_TT_Buffer | expand |
On Fri, 10 May 2019, 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. > > Here we update udev->devaddr in address_device callback function > (this USB device address is assigned by XHCI controller) and 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. > > Signed-off-by: Jim Lin <jilin@nvidia.com> > --- > v2: xhci_clear_tt_buffer_complete: add static, shorter indentation > , remove its claiming in xhci.h > v3: Add description for clearing_tt (xhci.h) > v4: Remove clearing_tt flag because hub_tt_work has hub->tt.lock > to protect for Clear_TT_Buffer to be run serially. > Remove xhci_clear_tt_buffer_complete as it's not necessary. > Same reason as the above. > Extend usb_hub_clear_tt_buffer parameter > v5: Not extending usb_hub_clear_tt_buffer parameter > Add description. > v6: Remove unused parameter slot_id from xhci_clear_hub_tt_buffer > v7: Add devaddr field in "struct usb_device" > v8: split as two patches > v9: no change > > drivers/usb/host/xhci-ring.c | 12 ++++++++++++ > drivers/usb/host/xhci.c | 1 + > 2 files changed, 13 insertions(+) > > diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c > index 9215a28dad40..739737faf752 100644 > --- a/drivers/usb/host/xhci-ring.c > +++ b/drivers/usb/host/xhci-ring.c > @@ -1786,6 +1786,17 @@ struct xhci_segment *trb_in_td(struct xhci_hcd *xhci, > return NULL; > } > > +static void xhci_clear_hub_tt_buffer(struct xhci_hcd *xhci, struct xhci_td *td) > +{ > + /* > + * As part of low/full-speed endpoint-halt processing > + * we must clear the TT buffer (USB 2.0 specification 11.17.5). > + */ > + if (td->urb->dev->tt && !usb_pipeint(td->urb->pipe) && > + (td->urb->dev->tt->hub != xhci_to_hcd(xhci)->self.root_hub)) > + usb_hub_clear_tt_buffer(td->urb); > +} > + > static void xhci_cleanup_halted_endpoint(struct xhci_hcd *xhci, > unsigned int slot_id, unsigned int ep_index, > unsigned int stream_id, struct xhci_td *td, > @@ -1804,6 +1815,7 @@ static void xhci_cleanup_halted_endpoint(struct xhci_hcd *xhci, > if (reset_type == EP_HARD_RESET) { > ep->ep_state |= EP_HARD_CLEAR_TOGGLE; > xhci_cleanup_stalled_ring(xhci, ep_index, stream_id, td); > + xhci_clear_hub_tt_buffer(xhci, td); > } > xhci_ring_cmd_db(xhci); > } How come there's no clear_tt_buffer_complete() callback? Without it, xhci-hcd won't know when the TT buffer has been cleared, and so it won't know when to restart the endpoint ring for the halted endpoint. Note: Restarting the endpoint ring before the TT buffer has been cleared is not safe. Alan Stern > diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c > index 7fa58c99f126..68b393e5a453 100644 > --- a/drivers/usb/host/xhci.c > +++ b/drivers/usb/host/xhci.c > @@ -4096,6 +4096,7 @@ static int xhci_setup_device(struct usb_hcd *hcd, struct usb_device *udev, > /* Zero the input context control for later use */ > ctrl_ctx->add_flags = 0; > ctrl_ctx->drop_flags = 0; > + udev->devaddr = (u8)(le32_to_cpu(slot_ctx->dev_state) & DEV_ADDR_MASK); > > xhci_dbg_trace(xhci, trace_xhci_dbg_address, > "Internal device address = %d", >
diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c index 9215a28dad40..739737faf752 100644 --- a/drivers/usb/host/xhci-ring.c +++ b/drivers/usb/host/xhci-ring.c @@ -1786,6 +1786,17 @@ struct xhci_segment *trb_in_td(struct xhci_hcd *xhci, return NULL; } +static void xhci_clear_hub_tt_buffer(struct xhci_hcd *xhci, struct xhci_td *td) +{ + /* + * As part of low/full-speed endpoint-halt processing + * we must clear the TT buffer (USB 2.0 specification 11.17.5). + */ + if (td->urb->dev->tt && !usb_pipeint(td->urb->pipe) && + (td->urb->dev->tt->hub != xhci_to_hcd(xhci)->self.root_hub)) + usb_hub_clear_tt_buffer(td->urb); +} + static void xhci_cleanup_halted_endpoint(struct xhci_hcd *xhci, unsigned int slot_id, unsigned int ep_index, unsigned int stream_id, struct xhci_td *td, @@ -1804,6 +1815,7 @@ static void xhci_cleanup_halted_endpoint(struct xhci_hcd *xhci, if (reset_type == EP_HARD_RESET) { ep->ep_state |= EP_HARD_CLEAR_TOGGLE; xhci_cleanup_stalled_ring(xhci, ep_index, stream_id, td); + xhci_clear_hub_tt_buffer(xhci, td); } xhci_ring_cmd_db(xhci); } diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c index 7fa58c99f126..68b393e5a453 100644 --- a/drivers/usb/host/xhci.c +++ b/drivers/usb/host/xhci.c @@ -4096,6 +4096,7 @@ static int xhci_setup_device(struct usb_hcd *hcd, struct usb_device *udev, /* Zero the input context control for later use */ ctrl_ctx->add_flags = 0; ctrl_ctx->drop_flags = 0; + udev->devaddr = (u8)(le32_to_cpu(slot_ctx->dev_state) & DEV_ADDR_MASK); xhci_dbg_trace(xhci, trace_xhci_dbg_address, "Internal device address = %d",
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. Here we update udev->devaddr in address_device callback function (this USB device address is assigned by XHCI controller) and 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. Signed-off-by: Jim Lin <jilin@nvidia.com> --- v2: xhci_clear_tt_buffer_complete: add static, shorter indentation , remove its claiming in xhci.h v3: Add description for clearing_tt (xhci.h) v4: Remove clearing_tt flag because hub_tt_work has hub->tt.lock to protect for Clear_TT_Buffer to be run serially. Remove xhci_clear_tt_buffer_complete as it's not necessary. Same reason as the above. Extend usb_hub_clear_tt_buffer parameter v5: Not extending usb_hub_clear_tt_buffer parameter Add description. v6: Remove unused parameter slot_id from xhci_clear_hub_tt_buffer v7: Add devaddr field in "struct usb_device" v8: split as two patches v9: no change drivers/usb/host/xhci-ring.c | 12 ++++++++++++ drivers/usb/host/xhci.c | 1 + 2 files changed, 13 insertions(+)