From: Daniel Mack daniel@zonque.org
[ Upstream commit 191227d99a281333b50aaf82ab4152fbfa249c19 ]
miniDSP USBStreamer UAC2 devices send clock validity changes with the control field set to zero. The current interrupt handler ignores all packets if the control field does not match the mixer element's, but it really should only do that in case that field is needed to distinguish multiple elements with the same ID.
This patch implements a logic that lets notifications packets pass if the element ID is unique for a given device.
Signed-off-by: Daniel Mack daniel@zonque.org Signed-off-by: Takashi Iwai tiwai@suse.de Signed-off-by: Sasha Levin sashal@kernel.org --- sound/usb/mixer.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-)
diff --git a/sound/usb/mixer.c b/sound/usb/mixer.c index a2a9712bd6fa7..eb98e60e57335 100644 --- a/sound/usb/mixer.c +++ b/sound/usb/mixer.c @@ -2391,6 +2391,7 @@ static void snd_usb_mixer_interrupt_v2(struct usb_mixer_interface *mixer, __u8 unitid = (index >> 8) & 0xff; __u8 control = (value >> 8) & 0xff; __u8 channel = value & 0xff; + unsigned int count = 0;
if (channel >= MAX_CHANNELS) { usb_audio_dbg(mixer->chip, @@ -2399,6 +2400,12 @@ static void snd_usb_mixer_interrupt_v2(struct usb_mixer_interface *mixer, return; }
+ for (list = mixer->id_elems[unitid]; list; list = list->next_id_elem) + count++; + + if (count == 0) + return; + for (list = mixer->id_elems[unitid]; list; list = list->next_id_elem) { struct usb_mixer_elem_info *info;
@@ -2406,7 +2413,7 @@ static void snd_usb_mixer_interrupt_v2(struct usb_mixer_interface *mixer, continue;
info = (struct usb_mixer_elem_info *)list; - if (info->control != control) + if (count > 1 && info->control != control) continue;
switch (attribute) {