[alsa-devel] no reset_resume for driver snd-usb-audio for logitech headset H600

[Clemens Ladisch]

Takashi Iwai wrote:
>> On Tue, 8 Oct 2013 baumber at hotmail.com wrote:
>>> https://bugzilla.kernel.org/show_bug.cgi?id=62691
>>>
>>> Summary: no reset_resume for driver snd-usb-audio for logitech headset H600
>
> How about simply applying the same resume for reset_resume like below?
>
> ---
>
> diff --git a/sound/usb/card.c b/sound/usb/card.c
> index 9d9de8d..c591a83 100644
> --- a/sound/usb/card.c
> +++ b/sound/usb/card.c
> @@ -747,6 +747,7 @@ static struct usb_driver usb_audio_driver = {
>  	.disconnect =	usb_audio_disconnect,
>  	.suspend =	usb_audio_suspend,
>  	.resume =	usb_audio_resume,
> +	.reset_resume =	usb_audio_resume,
>  	.id_table =	usb_audio_ids,
>  	.supports_autosuspend = 1,
>  };

When the device was reset, the state of all mixer controls has been
lost.  Disconnecting the card (the default behaviour without
reset_resume) is the correct thing to do in this situation.

Userspace should pick up the USB device again when it reappears.
(But it doesn't.  Is this a PulseAudio or a KDE problem?)

And why does the kernel whine about the lack of a callback that is
documented as being optional?


Regards,
Clemens