[BUG] Regression in v2.6.28 introduced by: 'USB: skip Set-Interface(0) if already in altsetting 0'

From: Jan Scholz
Date: Fri Jan 02 2009 - 06:35:17 EST


Hi,

In v2.6.28 my usb bluetooth device disappears after suspend to ram:

$ hcitool dev
Devices:
hci0 00:0D:93:15:D6:E8
$ echo mem > /sys/power/state
$ hcitool dev
Devices:
$

The problem does not occur with the (older) hci_usb.ko, but only with
btusb.ko.

This is the output of lsusb:
Bus 001 Device 003: ID 05ac:8203 Apple Computer, Inc. Bluetooth HCI

Bisecting finds commit 24c0996 (USB: skip Set-Interface(0) if already in
altsetting 0) as the first bad commit, and indeed if I use 2.6.28 with
24c0996 reverted, the bluetooth device survives suspend to ram.

If you need more information/test/etc please let me know.

Regards,
Jan

> commit 24c0996a6b73e2554104961afcc8659534503e0d
> Author: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>
> Date: Mon Dec 1 10:24:41 2008 -0500
>
> USB: skip Set-Interface(0) if already in altsetting 0
>
> When a driver unbinds from an interface, usbcore always sends a
> Set-Interface request to reinstall altsetting 0. Unforunately, quite
> a few devices have buggy firmware that crashes when it receives this
> request.
>
> To avoid such problems, this patch (as1180) arranges to send the
> Set-Interface request only when the interface is not already in
> altsetting 0.
>
> Signed-off-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>
> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>

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Jan Scholz ____ ____ __ ___
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