[29/40] xhci: Properly handle COMP_2ND_BW_ERR

[Greg KH]

3.0-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Hans de Goede <hdegoede@xxxxxxxxxx>

commit 71d85724bdd947a3b42a88d08af79f290a1a767b upstream.

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@xxxxxxxxxx>
Signed-off-by: Sarah Sharp <sarah.a.sharp@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>

---
 drivers/usb/host/xhci.c |    1 +
 drivers/usb/host/xhci.h |    1 -
 2 files changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -1568,6 +1568,7 @@ static int xhci_configure_endpoint_resul
 		/* 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;
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -900,7 +900,6 @@ 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


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