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Commit 5dae5fd24071319bb67d3375217d5b0b6d16cb0b

Authored by Eldad Zack
Committed by Takashi Iwai
1 parent 9f81410592
Exists in smarc-l5.0.0_1.0.0-ga and in 5 other branches imx_3.10.17_1.0.1_ga, imx_3.10.53_1.1.0_ga, imx_3.14.28_1.0.0_ga, smarc-imx_3.10.53_1.1.0_ga, smarc-imx_3.14.28_1.0.0_ga

ALSA: usb-audio: skip UAC2 EFFECT_UNIT 

Current code mishandles the case where the device is a UAC2
and the bDescriptorSubtype is a UAC2 Effect Unit (0x07).
It tries to parse it as a Processing Unit (which is similar to two
other UAC1 units with overlapping subtypes), but since the structure
is different (See: 4.7.2.10, 4.7.2.11 in UAC2 standard), the parsing
is done incorrectly and prevents the device from initializing.
For now, just ignore the unit.

Signed-off-by: Eldad Zack <eldad@fogrefinery.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

Showing 1 changed file with 12 additions and 1 deletions Side-by-side Diff

... ... @@ -723,8 +723,19 @@
723 723 return 0;
724 724 }
725 725 case UAC1_PROCESSING_UNIT:
726   - case UAC1_EXTENSION_UNIT: {
  726 + case UAC1_EXTENSION_UNIT:
  727 + /* UAC2_PROCESSING_UNIT_V2 */
  728 + /* UAC2_EFFECT_UNIT */ {
727 729 struct uac_processing_unit_descriptor *d = p1;
  730 +
  731 + if (state->mixer->protocol == UAC_VERSION_2 &&
  732 + hdr[2] == UAC2_EFFECT_UNIT) {
  733 + /* UAC2/UAC1 unit IDs overlap here in an
  734 + * uncompatible way. Ignore this unit for now.
  735 + */
  736 + return 0;
  737 + }
  738 +
728 739 if (d->bNrInPins) {
729 740 id = d->baSourceID[0];
730 741 break; /* continue to parse */