The recently introduced sample rate validation code seems causing a problem on some devices; namely, after performing this, the bus gets screwed and it influences even on other USB devices. As a quick workaround, perform it only for the necessary devices; currently MOTU devices are known to need the valid altset checks, so filter out other devices.

Fixes: 93db51d06b32 ("ALSA: usb-audio: Check valid altsetting at parsing rates for UAC2/3") Reported-by: Jamie Heilman jamie@audible.transient.net BugLink: https://bugzilla.suse.com/show_bug.cgi?id=1178203 Signed-off-by: Takashi Iwai tiwai@suse.de --- sound/usb/format.c | 11 +++++++++++ 1 file changed, 11 insertions(+)

diff --git a/sound/usb/format.c b/sound/usb/format.c index 9ebc5d202c87..e6ff317a6785 100644 --- a/sound/usb/format.c +++ b/sound/usb/format.c @@ -466,6 +466,17 @@ static int validate_sample_rate_table_v2v3(struct snd_usb_audio *chip, unsigned int nr_rates; int i, err;

+ /* performing the rate verification may lead to unexpected USB bus + * behavior afterwards by some unknown reason. Do this only for the + * known devices. + */ + switch (USB_ID_VENDOR(chip->usb_id)) { + case 0x07fd: /* MOTU */ + break; + default: + return 0; /* don't perform the validation as default */ + } + table = kcalloc(fp->nr_rates, sizeof(*table), GFP_KERNEL); if (!table) return -ENOMEM;