Commit c5379cf6 authored by Roger Quadros's avatar Roger Quadros Committed by Greg Kroah-Hartman

usb: xhci: bInterval quirk for TI TUSB73x0

commit 69307ccb upstream.

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.pdfSigned-off-by: default avatarRoger Quadros <rogerq@ti.com>
Signed-off-by: default avatarMathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent f9a45058
......@@ -1502,6 +1502,17 @@ 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);
......
......@@ -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");
......
......@@ -1818,6 +1818,7 @@ 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;
......
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