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authorChunfeng Yun <chunfeng.yun@mediatek.com>2015-12-04 15:53:43 +0200
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2016-01-31 11:23:35 -0800
commitabcbfda367d4eb2b17dc9c5b036c99431ed3ea3c (patch)
tree0cf73572d7249822b597fc9f127710ab41690584 /drivers
parent1f6a2cc39913518756d8b4dad4a10493d208f4c2 (diff)
usb: xhci: fix config fail of FS hub behind a HS hub with MTT
commit 096b110a3dd3c868e4610937c80d2e3f3357c1a9 upstream. if a full speed hub connects to a high speed hub which supports MTT, the MTT field of its slot context will be set to 1 when xHCI driver setups an xHCI virtual device in xhci_setup_addressable_virt_dev(); once usb core fetch its hub descriptor, and need to update the xHC's internal data structures for the device, the HUB field of its slot context will be set to 1 too, meanwhile MTT is also set before, this will cause configure endpoint command fail, so in the case, we should clear MTT to 0 for full speed hub according to section 6.2.2 Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com> Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers')
-rw-r--r--drivers/usb/host/xhci.c8
1 files changed, 8 insertions, 0 deletions
diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index 1e6d7579709e..471f73e151ae 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -4794,8 +4794,16 @@ int xhci_update_hub_device(struct usb_hcd *hcd, struct usb_device *hdev,
ctrl_ctx->add_flags |= cpu_to_le32(SLOT_FLAG);
slot_ctx = xhci_get_slot_ctx(xhci, config_cmd->in_ctx);
slot_ctx->dev_info |= cpu_to_le32(DEV_HUB);
+ /*
+ * refer to section 6.2.2: MTT should be 0 for full speed hub,
+ * but it may be already set to 1 when setup an xHCI virtual
+ * device, so clear it anyway.
+ */
if (tt->multi)
slot_ctx->dev_info |= cpu_to_le32(DEV_MTT);
+ else if (hdev->speed == USB_SPEED_FULL)
+ slot_ctx->dev_info &= cpu_to_le32(~DEV_MTT);
+
if (xhci->hci_version > 0x95) {
xhci_dbg(xhci, "xHCI version %x needs hub "
"TT think time and number of ports\n",