On Thu, 01 Sep 2022 12:06:25 +0200,
chihhao chen wrote:
>
> Hi Takashi,
>
> I tested the patch and USB audio function works well.
> (Start and stop playback more than 20 times with Samsung USB C
> Earphone)
Great, thanks for quick testing!
Takashi
>
> Thanks
>
> On Thu, 2022-09-01 at 10:28 +0200, Takashi Iwai wrote:
> > On Thu, 01 Sep 2022 09:51:37 +0200,
> > Takashi Iwai wrote:
> > >
> > > On Thu, 01 Sep 2022 07:50:40 +0200,
> > > chihhao chen wrote:
> > > >
> > > > Hi Takashi,
> > > >
> > > > The patch fixes this problem.
> > > > I tried it with "Product: Samsung USB C Earphone" and missing
> > > > sound
> > > > problem cannot be reproduced.
> > >
> > > OK, it's a good news. I'm going to add more information to the
> > > patch
> > > description about the regression and submit the patch.
> >
> > Could you check whether the below cleanup patch on top of the
> > previous
> > one doesn't break things? I lightly tested on my devices and don't
> > believe it would change the actual behavior, but just to be sure.
> >
> >
> > Takashi
> >
> > -- 8< --
> > From: Takashi Iwai <tiwai@xxxxxxx>
> > Subject: [PATCH] ALSA: usb-audio: Clean up endpoint setups at PCM
> > prepare
> >
> > This patch cleans up the superfluous checks and calls for setting up
> > the endpoints at PCM prepare callback:
> >
> > - Drop stop_endpoints() and sync_pending_stops() calls; the stream is
> > guaranteed to have been already stopped and synced at each PCM
> > prepare call by ALSA PCM core
> >
> > - Call snd_usb_endpoint_prepare() unconditionally;
> > the check for endpoint->need_setup is done in
> > snd_pcm_hw_endpoint_prepare() itself
> >
> > - Apply snd_usb_set_format_quirk() only when the endpoint is actually
> > set up (i.e. the return code from snd_usb_endpoint_prepare() > 0)
> >
> > - Move a few lines back into snd_usb_pcm_prepare();
> > it's even easier to follow than a small useless function
> >
> > Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
> > ---
> > sound/usb/pcm.c | 40 ++++++++++------------------------------
> > 1 file changed, 10 insertions(+), 30 deletions(-)
> >
> > diff --git a/sound/usb/pcm.c b/sound/usb/pcm.c
> > index b604f7e95e82..4ed53a3dc922 100644
> > --- a/sound/usb/pcm.c
> > +++ b/sound/usb/pcm.c
> > @@ -433,35 +433,6 @@ static void close_endpoints(struct snd_usb_audio
> > *chip,
> > }
> > }
> >
> > -static int configure_endpoints(struct snd_usb_audio *chip,
> > - struct snd_usb_substream *subs)
> > -{
> > - int err;
> > -
> > - if (subs->data_endpoint->need_setup) {
> > - /* stop any running stream beforehand */
> > - if (stop_endpoints(subs, false))
> > - sync_pending_stops(subs);
> > - if (subs->sync_endpoint) {
> > - err = snd_usb_endpoint_prepare(chip, subs-
> > >sync_endpoint);
> > - if (err < 0)
> > - return err;
> > - }
> > - err = snd_usb_endpoint_prepare(chip, subs-
> > >data_endpoint);
> > - if (err < 0)
> > - return err;
> > - snd_usb_set_format_quirk(subs, subs->cur_audiofmt);
> > - } else {
> > - if (subs->sync_endpoint) {
> > - err = snd_usb_endpoint_prepare(chip, subs-
> > >sync_endpoint);
> > - if (err < 0)
> > - return err;
> > - }
> > - }
> > -
> > - return 0;
> > -}
> > -
> > /*
> > * hw_params callback
> > *
> > @@ -640,9 +611,18 @@ static int snd_usb_pcm_prepare(struct
> > snd_pcm_substream *substream)
> > goto unlock;
> > }
> >
> > - ret = configure_endpoints(chip, subs);
> > + if (subs->sync_endpoint) {
> > + ret = snd_usb_endpoint_prepare(chip, subs-
> > >sync_endpoint);
> > + if (ret < 0)
> > + goto unlock;
> > + }
> > +
> > + ret = snd_usb_endpoint_prepare(chip, subs->data_endpoint);
> > if (ret < 0)
> > goto unlock;
> > + else if (ret > 0)
> > + snd_usb_set_format_quirk(subs, subs->cur_audiofmt);
> > + ret = 0;
> >
> > /* reset the pointer */
> > subs->buffer_bytes = frames_to_bytes(runtime, runtime-
> > >buffer_size);
>
