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usb: xhci: bInterval quirk for TI TUSB73x0

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As per [1] issue #4,
"The periodic EP scheduler always tries to schedule the EPs
that have large intervals (interval equal to or greater than
128 microframes) into different microframes. So it maintains
an internal counter and increments for each large interval
EP added. When the counter is greater than 128, the scheduler
rejects the new EP. So when the hub re-enumerated 128 times,
it triggers this condition."

This results in Bandwidth error when devices with periodic
endpoints (ISO/INT) having bInterval > 7 are plugged and
unplugged several times on a TUSB73x0 XHCI host.

Workaround this issue by limiting the bInterval to 7
(i.e. interval to 6) for High-speed or faster periodic endpoints.

[1] - http://www.ti.com/lit/er/sllz076/sllz076.pdf

Cc: stable <stable@vger.kernel.org>
Signed-off-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Roger Quadros 2017-04-07 17:57:12 +03:00 committed by Greg Kroah-Hartman
parent d2561626b9
commit 69307ccb9a
3 changed files with 15 additions and 0 deletions
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11
drivers/usb/host/xhci-mem.c
View File

@ -1503,6 +1503,17 @@ int xhci_endpoint_init(struct xhci_hcd *xhci,
*/
max_esit_payload = xhci_get_max_esit_payload(udev, ep);
interval = xhci_get_endpoint_interval(udev, ep);
/* Periodic endpoint bInterval limit quirk */
if (usb_endpoint_xfer_int(&ep->desc) ||
usb_endpoint_xfer_isoc(&ep->desc)) {
if ((xhci->quirks & XHCI_LIMIT_ENDPOINT_INTERVAL_7) &&
udev->speed >= USB_SPEED_HIGH &&
interval >= 7) {
interval = 6;
}
}
mult = xhci_get_endpoint_mult(udev, ep);
max_packet = usb_endpoint_maxp(&ep->desc);
max_burst = xhci_get_endpoint_max_burst(udev, ep);

3
drivers/usb/host/xhci-pci.c
View File

@ -199,6 +199,9 @@ static void xhci_pci_quirks(struct device *dev, struct xhci_hcd *xhci)
pdev->device == 0x1042)
xhci->quirks |= XHCI_BROKEN_STREAMS;
if (pdev->vendor == PCI_VENDOR_ID_TI && pdev->device == 0x8241)
xhci->quirks |= XHCI_LIMIT_ENDPOINT_INTERVAL_7;
if (xhci->quirks & XHCI_RESET_ON_RESUME)
xhci_dbg_trace(xhci, trace_xhci_dbg_quirks,
"QUIRK: Resetting on resume");

1
drivers/usb/host/xhci.h
View File

@ -1820,6 +1820,7 @@ struct xhci_hcd {
#define XHCI_MISSING_CAS (1 << 24)
/* For controller with a broken Port Disable implementation */
#define XHCI_BROKEN_PORT_PED (1 << 25)
#define XHCI_LIMIT_ENDPOINT_INTERVAL_7 (1 << 26)
unsigned int num_active_eps;
unsigned int limit_active_eps;