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| author | Takashi Iwai <tiwai@suse.de> | 2022-09-20 20:11:26 +0200 |
|---|---|---|
| committer | Takashi Iwai <tiwai@suse.de> | 2022-09-20 20:12:50 +0200 |
| commit | 9a737e7f8b371e97eb649904276407cee2c9cf30 (patch) | |
| tree | eefff8ea3e026e9b0a2f421239b707ed057fb6d3 /sound | |
| parent | ALSA: usb-audio: Split endpoint setups for hw_params and prepare (take#2) (diff) | |
| download | linux-9a737e7f8b371e97eb649904276407cee2c9cf30.tar.xz linux-9a737e7f8b371e97eb649904276407cee2c9cf30.zip | |
ALSA: usb-audio: Properly refcounting clock rate
We fixed the bug introduced by the patch for managing the shared
clocks at the commit 809f44a0cc5a ("ALSA: usb-audio: Clear fixed clock
rate at closing EP"), but it was merely a workaround. By this change,
the clock reference rate is cleared at each EP close, hence the still
remaining EP may need a re-setup of rate unnecessarily.
This patch introduces the proper refcounting for the clock reference
object so that the clock setup is done only when needed.
Fixes: 809f44a0cc5a ("ALSA: usb-audio: Clear fixed clock rate at closing EP")
Fixes: c11117b634f4 ("ALSA: usb-audio: Refcount multiple accesses on the single clock")
Link: https://lore.kernel.org/r/20220920181126.4912-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Diffstat (limited to 'sound')
| -rw-r--r-- | sound/usb/endpoint.c | 11 |
1 files changed, 7 insertions, 4 deletions
diff --git a/sound/usb/endpoint.c b/sound/usb/endpoint.c index 0c94ebc98e90..b2d0b42b581f 100644 --- a/sound/usb/endpoint.c +++ b/sound/usb/endpoint.c @@ -39,6 +39,7 @@ struct snd_usb_iface_ref { struct snd_usb_clock_ref { unsigned char clock; atomic_t locked; + int opened; int rate; bool need_setup; struct list_head list; @@ -803,6 +804,7 @@ snd_usb_endpoint_open(struct snd_usb_audio *chip, ep = NULL; goto unlock; } + ep->clock_ref->opened++; } ep->cur_audiofmt = fp; @@ -926,8 +928,10 @@ void snd_usb_endpoint_close(struct snd_usb_audio *chip, endpoint_set_interface(chip, ep, false); if (!--ep->opened) { - if (ep->clock_ref && !atomic_read(&ep->clock_ref->locked)) - ep->clock_ref->rate = 0; + if (ep->clock_ref) { + if (!--ep->clock_ref->opened) + ep->clock_ref->rate = 0; + } ep->iface = 0; ep->altsetting = 0; ep->cur_audiofmt = NULL; @@ -1649,8 +1653,7 @@ void snd_usb_endpoint_stop(struct snd_usb_endpoint *ep, bool keep_pending) WRITE_ONCE(ep->sync_source->sync_sink, NULL); stop_urbs(ep, false, keep_pending); if (ep->clock_ref) - if (!atomic_dec_return(&ep->clock_ref->locked)) - ep->clock_ref->rate = 0; + atomic_dec(&ep->clock_ref->locked); } } |