dect
/
linux-2.6
Archived
13
0
Fork 0
Code Releases Activity

xhci: Properly handle COMP_2ND_BW_ERR 

I encountered a result of COMP_2ND_BW_ERR while improving how the pwc
webcam driver handles not having the full usb1 bandwidth available to
itself.

I created the following test setup, a NEC xhci controller with a
single TT USB 2 hub plugged into it, with a usb keyboard and a pwc webcam
plugged into the usb2 hub. This caused the following to show up in dmesg
when trying to stream from the pwc camera at its highest alt setting:

xhci_hcd 0000:01:00.0: ERROR: unexpected command completion code 0x23.
usb 6-2.1: Not enough bandwidth for altsetting 9

And usb_set_interface returned -EINVAL, which caused my pwc code to not
do the right thing as it expected -ENOSPC.

This patch makes the xhci driver properly handle COMP_2ND_BW_ERR and makes
usb_set_interface return -ENOSPC as expected.

This should be backported to stable kernels as old as 2.6.32.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable@vger.kernel.org
This commit is contained in:
Hans de Goede 2012-01-04 23:29:18 +01:00 committed by Sarah Sharp
parent e78832cdca
commit 71d85724bd
2 changed files with 1 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

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

@ -1623,6 +1623,7 @@ static int xhci_configure_endpoint_result(struct xhci_hcd *xhci,
/* FIXME: can we allocate more resources for the HC? */
break;
case COMP_BW_ERR:
case COMP_2ND_BW_ERR:
dev_warn(&udev->dev, "Not enough bandwidth "
"for new device state.\n");
ret = -ENOSPC;

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

@ -1033,7 +1033,6 @@ struct xhci_transfer_event {
/* Invalid Stream ID Error */
#define COMP_STRID_ERR 34
/* Secondary Bandwidth Error - may be returned by a Configure Endpoint cmd */
/* FIXME - check for this */
#define COMP_2ND_BW_ERR 35
/* Split Transaction Error */
#define COMP_SPLIT_ERR 36