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Date:   Mon, 05 Sep 2022 15:00:20 +0200
Message-ID: <87ilm2j7rv.wl-tiwai@suse.de>
From:   Takashi Iwai <tiwai@suse.de>
To:     Thomas Zimmermann <tzimmermann@suse.de>
Cc:     Takashi Iwai <tiwai@suse.de>, linux-kernel@vger.kernel.org,
        dri-devel@lists.freedesktop.org
Subject: Re: [PATCH 12/12] drm/udl: Sync pending URBs at the end of suspend
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References: <20220816153655.27526-1-tiwai@suse.de>
        <20220816153655.27526-13-tiwai@suse.de>
        <d3a0faf3-14ae-04a7-affe-4cd64570855f@suse.de>
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On Mon, 05 Sep 2022 10:44:25 +0200,
Thomas Zimmermann wrote:
> 
> Hi
> 
> Am 16.08.22 um 17:36 schrieb Takashi Iwai:
> > It's better to perform the sync at the very last of the suspend
> > instead of the pipe-disable function, so that we can catch all pending
> > URBs (if any).
> > 
> > While we're at it, drop the error code from udl_sync_pending_urb()
> > since we basically ignore it; instead, give a clear error message
> > indicating a problem.
> 
> But if we fail, shouldn't we report that error to the caller of the
> suspend function?

It's an open question.  We may fail the suspend, but OTOH, the sync
error is likely nothing we can recover from at any time later, either;
that is, even if we return an error and abort the suspend, it wouldn't
help so much from the practical POV.  So for now -- and just for this
URL device handling -- I'm inclined to continue suspending.  But if
anyone has more strong argument against it, I'm all ears.


thanks,

Takashi