| Message ID | 1556593592-3078-1-git-send-email-jilin@nvidia.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [v3,1/1] usb: xhci: Add Clear_TT_Buffer | expand |
On 30.4.2019 6.06, 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". Good point, xhci isn't making sure TT buffers get cleared when they should. > > 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 add Clear_TT_Buffer for the following Set_Interface requests > 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) > > drivers/usb/host/xhci-ring.c | 28 ++++++++++++++++++++++++++++ > drivers/usb/host/xhci.c | 7 +++++++ > drivers/usb/host/xhci.h | 2 ++ > 3 files changed, 37 insertions(+) > > diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c > index 9215a28dad40..02b1ebad81e7 100644 > --- a/drivers/usb/host/xhci-ring.c > +++ b/drivers/usb/host/xhci-ring.c > @@ -1786,6 +1786,33 @@ struct xhci_segment *trb_in_td(struct xhci_hcd *xhci, > return NULL; > } > > +static void xhci_clear_hub_tt_buffer(struct xhci_hcd *xhci, > + unsigned int slot_id, struct xhci_td *td) > +{ > + struct xhci_virt_device *dev; > + struct xhci_slot_ctx *slot_ctx; > + int saved_devnum; > + > + /* > + * 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) && > + !xhci->clearing_tt) { > + xhci->clearing_tt = 1; one xhci->clearing_tt under is not enough, there might be several HS hubs, or multi TT hubs with halted endpoints at the same time that need TT clearing. How about a flag per endpoint? For example Aadding a EP_CLEARING_TT flag for ep_state in struct xhci_virt_ep? just like EP_STOP_CMD_PENDING, or EP_HALTED > + dev = xhci->devs[slot_id]; > + slot_ctx = xhci_get_slot_ctx(xhci, dev->out_ctx); > + /* Update devnum temporarily for usb_hub_clear_tt_buffer */ > + saved_devnum = td->urb->dev->devnum; > + td->urb->dev->devnum = (int) le32_to_cpu(slot_ctx->dev_state) & > + DEV_ADDR_MASK; Changing the struct usb_device devnum on the fly seems like a bit of a hack, and probably causes issues elsewhere. Devnum is tied to uevents, usbfs, sysfs etc. We need another solution, some options: - Let usb_hub_clear_tt_buffer() figure out address and not just use devnum if host == xhci. - Add address to struct usb_device, (would have both address and devnum), use it when needed. - Provide address as parameter to usb_clear_tt_buffer() (api change, changes other host drivers) - Force devnum to be same as address, usb core can't choose address for xhci devices. -Mathias
On 2019年05月02日 18:56, Mathias Nyman wrote: > On 30.4.2019 6.06, 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". > > Good point, xhci isn't making sure TT buffers get cleared when they > should. > >> >> 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 add Clear_TT_Buffer for the following Set_Interface requests >> 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) >> >> drivers/usb/host/xhci-ring.c | 28 ++++++++++++++++++++++++++++ >> drivers/usb/host/xhci.c | 7 +++++++ >> drivers/usb/host/xhci.h | 2 ++ >> 3 files changed, 37 insertions(+) >> >> diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c >> index 9215a28dad40..02b1ebad81e7 100644 >> --- a/drivers/usb/host/xhci-ring.c >> +++ b/drivers/usb/host/xhci-ring.c >> @@ -1786,6 +1786,33 @@ struct xhci_segment *trb_in_td(struct xhci_hcd >> *xhci, >> return NULL; >> } >> +static void xhci_clear_hub_tt_buffer(struct xhci_hcd *xhci, >> + unsigned int slot_id, struct xhci_td *td) >> +{ >> + struct xhci_virt_device *dev; >> + struct xhci_slot_ctx *slot_ctx; >> + int saved_devnum; >> + >> + /* >> + * 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) && >> + !xhci->clearing_tt) { >> + xhci->clearing_tt = 1; > > one xhci->clearing_tt under is not enough, there might be several HS > hubs, or > multi TT hubs with halted endpoints at the same time that need TT > clearing. > > How about a flag per endpoint? > > For example Aadding a EP_CLEARING_TT flag for ep_state in struct > xhci_virt_ep? > just like EP_STOP_CMD_PENDING, or EP_HALTED > >> + dev = xhci->devs[slot_id]; >> + slot_ctx = xhci_get_slot_ctx(xhci, dev->out_ctx); >> + /* Update devnum temporarily for usb_hub_clear_tt_buffer */ >> + saved_devnum = td->urb->dev->devnum; >> + td->urb->dev->devnum = (int) le32_to_cpu(slot_ctx->dev_state) & >> + DEV_ADDR_MASK; > > Changing the struct usb_device devnum on the fly seems like a bit of a > hack, and probably > causes issues elsewhere. Devnum is tied to uevents, usbfs, sysfs etc. > > We need another solution, some options: > > - Let usb_hub_clear_tt_buffer() figure out address and not just use > devnum if host == xhci. > - Add address to struct usb_device, (would have both address and > devnum), use it when needed. > - Provide address as parameter to usb_clear_tt_buffer() (api change, > changes other host drivers) > - Force devnum to be same as address, usb core can't choose address > for xhci devices. > > -Mathias Thanks for review. Will try. --nvpublic
diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c index 9215a28dad40..02b1ebad81e7 100644 --- a/drivers/usb/host/xhci-ring.c +++ b/drivers/usb/host/xhci-ring.c @@ -1786,6 +1786,33 @@ struct xhci_segment *trb_in_td(struct xhci_hcd *xhci, return NULL; } +static void xhci_clear_hub_tt_buffer(struct xhci_hcd *xhci, + unsigned int slot_id, struct xhci_td *td) +{ + struct xhci_virt_device *dev; + struct xhci_slot_ctx *slot_ctx; + int saved_devnum; + + /* + * 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) && + !xhci->clearing_tt) { + xhci->clearing_tt = 1; + dev = xhci->devs[slot_id]; + slot_ctx = xhci_get_slot_ctx(xhci, dev->out_ctx); + /* Update devnum temporarily for usb_hub_clear_tt_buffer */ + saved_devnum = td->urb->dev->devnum; + td->urb->dev->devnum = (int) le32_to_cpu(slot_ctx->dev_state) & + DEV_ADDR_MASK; + if (usb_hub_clear_tt_buffer(td->urb)) + xhci->clearing_tt = 0; + td->urb->dev->devnum = saved_devnum; + } +} + 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 +1831,7 @@ 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, slot_id, td); } xhci_ring_cmd_db(xhci); } diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c index 7fa58c99f126..4890c3518aa3 100644 --- a/drivers/usb/host/xhci.c +++ b/drivers/usb/host/xhci.c @@ -5132,6 +5132,12 @@ int xhci_gen_setup(struct usb_hcd *hcd, xhci_get_quirks_t get_quirks) } EXPORT_SYMBOL_GPL(xhci_gen_setup); +static void xhci_clear_tt_buffer_complete(struct usb_hcd *hcd, + struct usb_host_endpoint *ep) +{ + hcd_to_xhci(hcd)->clearing_tt = 0; +} + static const struct hc_driver xhci_hc_driver = { .description = "xhci-hcd", .product_desc = "xHCI Host Controller", @@ -5192,6 +5198,7 @@ static const struct hc_driver xhci_hc_driver = { .enable_usb3_lpm_timeout = xhci_enable_usb3_lpm_timeout, .disable_usb3_lpm_timeout = xhci_disable_usb3_lpm_timeout, .find_raw_port_number = xhci_find_raw_port_number, + .clear_tt_buffer_complete = xhci_clear_tt_buffer_complete, }; void xhci_init_driver(struct hc_driver *drv, diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h index 9334cdee382a..dab1476e5bdf 100644 --- a/drivers/usb/host/xhci.h +++ b/drivers/usb/host/xhci.h @@ -1864,6 +1864,8 @@ struct xhci_hcd { unsigned hw_lpm_support:1; /* Broken Suspend flag for SNPS Suspend resume issue */ unsigned broken_suspend:1; + /* Clear_TT_Buffer in progress */ + unsigned clearing_tt:1; /* cached usb2 extened protocol capabilites */ u32 *ext_caps; unsigned int num_ext_caps;
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 add Clear_TT_Buffer for the following Set_Interface requests 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) drivers/usb/host/xhci-ring.c | 28 ++++++++++++++++++++++++++++ drivers/usb/host/xhci.c | 7 +++++++ drivers/usb/host/xhci.h | 2 ++ 3 files changed, 37 insertions(+)