[PATCH v4 1/1] usb: xhci: Add Clear_TT_Buffer
From: Jim Lin
Date: Mon May 06 2019 - 11:11:04 EST
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.
Originally usb_hub_clear_tt_buffer uses urb->dev->devnum as device
address while sending Clear_TT_Buffer command, but this doesn't work
for XHCI.
We have to extend usb_hub_clear_tt_buffer parameter to specify device
number that will have the TT state of its hub cleared.
Signed-off-by: Jim Lin <jilin@xxxxxxxxxx>
---
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
drivers/usb/core/hub.c | 5 +++--
drivers/usb/dwc2/hcd_intr.c | 2 +-
drivers/usb/host/ehci-q.c | 2 +-
drivers/usb/host/fotg210-hcd.c | 2 +-
drivers/usb/host/xhci-ring.c | 22 ++++++++++++++++++++++
drivers/usb/isp1760/isp1760-hcd.c | 5 +++--
include/linux/usb/hcd.h | 2 +-
7 files changed, 32 insertions(+), 8 deletions(-)
diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index 15a2934dc29d..4dec054c9776 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -840,6 +840,7 @@ int usb_hub_set_port_power(struct usb_device *hdev, struct usb_hub *hub,
/**
* usb_hub_clear_tt_buffer - clear control/bulk TT state in high speed hub
* @urb: an URB associated with the failed or incomplete split transaction
+ * @devnum : device number that will have the TT state of its hub cleared
*
* High speed HCDs use this to tell the hub driver that some split control or
* bulk transaction failed in a way that requires clearing internal state of
@@ -851,7 +852,7 @@ int usb_hub_set_port_power(struct usb_device *hdev, struct usb_hub *hub,
*
* Return: 0 if successful. A negative error code otherwise.
*/
-int usb_hub_clear_tt_buffer(struct urb *urb)
+int usb_hub_clear_tt_buffer(struct urb *urb, int devnum)
{
struct usb_device *udev = urb->dev;
int pipe = urb->pipe;
@@ -873,7 +874,7 @@ int usb_hub_clear_tt_buffer(struct urb *urb)
/* info that CLEAR_TT_BUFFER needs */
clear->tt = tt->multi ? udev->ttport : 1;
clear->devinfo = usb_pipeendpoint (pipe);
- clear->devinfo |= udev->devnum << 4;
+ clear->devinfo |= devnum << 4;
clear->devinfo |= usb_pipecontrol(pipe)
? (USB_ENDPOINT_XFER_CONTROL << 11)
: (USB_ENDPOINT_XFER_BULK << 11);
diff --git a/drivers/usb/dwc2/hcd_intr.c b/drivers/usb/dwc2/hcd_intr.c
index 88b5dcf3aefc..a3bb6911a62a 100644
--- a/drivers/usb/dwc2/hcd_intr.c
+++ b/drivers/usb/dwc2/hcd_intr.c
@@ -125,7 +125,7 @@ static void dwc2_hc_handle_tt_clear(struct dwc2_hsotg *hsotg,
if (qtd->urb->status != -EPIPE && qtd->urb->status != -EREMOTEIO) {
chan->qh->tt_buffer_dirty = 1;
- if (usb_hub_clear_tt_buffer(usb_urb))
+ if (usb_hub_clear_tt_buffer(usb_urb, usb_urb->dev->devnum))
/* Clear failed; let's hope things work anyway */
chan->qh->tt_buffer_dirty = 0;
}
diff --git a/drivers/usb/host/ehci-q.c b/drivers/usb/host/ehci-q.c
index aa2f77f1506d..9f64c260239e 100644
--- a/drivers/usb/host/ehci-q.c
+++ b/drivers/usb/host/ehci-q.c
@@ -169,7 +169,7 @@ static void ehci_clear_tt_buffer(struct ehci_hcd *ehci, struct ehci_qh *qh,
if (!ehci_is_TDI(ehci)
|| urb->dev->tt->hub !=
ehci_to_hcd(ehci)->self.root_hub) {
- if (usb_hub_clear_tt_buffer(urb) == 0)
+ if (!usb_hub_clear_tt_buffer(urb, urb->dev->devnum))
qh->clearing_tt = 1;
} else {
diff --git a/drivers/usb/host/fotg210-hcd.c b/drivers/usb/host/fotg210-hcd.c
index 0da68df259c8..bd29ed0fbd46 100644
--- a/drivers/usb/host/fotg210-hcd.c
+++ b/drivers/usb/host/fotg210-hcd.c
@@ -2123,7 +2123,7 @@ static void fotg210_clear_tt_buffer(struct fotg210_hcd *fotg210,
if (urb->dev->tt->hub !=
fotg210_to_hcd(fotg210)->self.root_hub) {
- if (usb_hub_clear_tt_buffer(urb) == 0)
+ if (!usb_hub_clear_tt_buffer(urb, urb->dev->devnum))
qh->clearing_tt = 1;
}
}
diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index 9215a28dad40..aa2a21e6cde3 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -1786,6 +1786,27 @@ 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 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)) {
+ dev = xhci->devs[slot_id];
+ slot_ctx = xhci_get_slot_ctx(xhci, dev->out_ctx);
+ devnum = (int) le32_to_cpu(slot_ctx->dev_state) &
+ DEV_ADDR_MASK;
+ usb_hub_clear_tt_buffer(td->urb, 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 +1825,7 @@ 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/isp1760/isp1760-hcd.c b/drivers/usb/isp1760/isp1760-hcd.c
index 8142c6b4c4cf..f1d68092becb 100644
--- a/drivers/usb/isp1760/isp1760-hcd.c
+++ b/drivers/usb/isp1760/isp1760-hcd.c
@@ -1166,7 +1166,8 @@ static void handle_done_ptds(struct usb_hcd *hcd)
(qtd->urb->status != -EPIPE) &&
(qtd->urb->status != -EREMOTEIO)) {
qh->tt_buffer_dirty = 1;
- if (usb_hub_clear_tt_buffer(qtd->urb))
+ if (usb_hub_clear_tt_buffer(qtd->urb,
+ qtd->urb->dev->devnum))
/* Clear failed; let's hope things work
anyway */
qh->tt_buffer_dirty = 0;
@@ -1633,7 +1634,7 @@ static void dequeue_urb_from_qtd(struct usb_hcd *hcd, struct isp1760_qh *qh,
if ((urb->dev->speed != USB_SPEED_HIGH) && urb_was_running) {
qh->tt_buffer_dirty = 1;
- if (usb_hub_clear_tt_buffer(urb))
+ if (usb_hub_clear_tt_buffer(urb, urb->dev->devnum))
/* Clear failed; let's hope things work anyway */
qh->tt_buffer_dirty = 0;
}
diff --git a/include/linux/usb/hcd.h b/include/linux/usb/hcd.h
index 695931b03684..01720f1f7d62 100644
--- a/include/linux/usb/hcd.h
+++ b/include/linux/usb/hcd.h
@@ -559,7 +559,7 @@ struct usb_tt_clear {
struct usb_host_endpoint *ep;
};
-extern int usb_hub_clear_tt_buffer(struct urb *urb);
+extern int usb_hub_clear_tt_buffer(struct urb *urb, int devnum);
extern void usb_ep0_reinit(struct usb_device *);
/* (shifted) direction/type/recipient from the USB 2.0 spec, table 9.2 */
--
2.1.4