summaryrefslogtreecommitdiff
path: root/sound/usb
diff options
context:
space:
mode:
authorTakashi Iwai <tiwai@suse.de>2022-09-20 20:11:26 +0200
committerTakashi Iwai <tiwai@suse.de>2022-09-20 20:12:50 +0200
commit9a737e7f8b371e97eb649904276407cee2c9cf30 (patch)
treeeefff8ea3e026e9b0a2f421239b707ed057fb6d3 /sound/usb
parent2be79d58645465351af5320eb14c70a94724c5ef (diff)
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/usb')
-rw-r--r--sound/usb/endpoint.c11
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);
}
}