4.20-stable review patch. If anyone has any objections, please let me know.
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From: Manuel Reinhardt manuel.rhdt@gmail.com
commit 2bc16b9f3223d049b57202ee702fcb5b9b507019 upstream.
The commit a60945fd08e4 ("ALSA: usb-audio: move implicit fb quirks to separate function") introduced an error in the handling of quirks for implicit feedback endpoints. This commit fixes this.
If a quirk successfully sets up an implicit feedback endpoint, usb-audio no longer tries to find the implicit fb endpoint itself.
Fixes: a60945fd08e4 ("ALSA: usb-audio: move implicit fb quirks to separate function") Signed-off-by: Manuel Reinhardt manuel.rhdt@gmail.com Cc: stable@vger.kernel.org Signed-off-by: Takashi Iwai tiwai@suse.de Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- sound/usb/pcm.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-)
--- a/sound/usb/pcm.c +++ b/sound/usb/pcm.c @@ -314,6 +314,9 @@ static int search_roland_implicit_fb(str return 0; }
+/* Setup an implicit feedback endpoint from a quirk. Returns 0 if no quirk + * applies. Returns 1 if a quirk was found. + */ static int set_sync_ep_implicit_fb_quirk(struct snd_usb_substream *subs, struct usb_device *dev, struct usb_interface_descriptor *altsd, @@ -384,7 +387,7 @@ add_sync_ep:
subs->data_endpoint->sync_master = subs->sync_endpoint;
- return 0; + return 1; }
static int set_sync_endpoint(struct snd_usb_substream *subs, @@ -423,6 +426,10 @@ static int set_sync_endpoint(struct snd_ if (err < 0) return err;
+ /* endpoint set by quirk */ + if (err > 0) + return 0; + if (altsd->bNumEndpoints < 2) return 0;