svn commit: r241988 - head/sys/dev/sound/usb

[Hans Petter Selasky]

Author: hselasky
Date: Wed Oct 24 08:00:01 2012
New Revision: 241988
URL: http://svn.freebsd.org/changeset/base/241988

Log:
  Fix USB audio specification compliance by filtering which descriptors can
  appear on which interface. This fixes detection of some USB audio adapters.
  Also increase the channel limit for FULL speed devices to 4 channels.
  
  Tested by:	gavin
  MFC after:	1 week

Modified:
  head/sys/dev/sound/usb/uaudio.c

Modified: head/sys/dev/sound/usb/uaudio.c
==============================================================================
--- head/sys/dev/sound/usb/uaudio.c	Wed Oct 24 07:23:29 2012	(r241987)
+++ head/sys/dev/sound/usb/uaudio.c	Wed Oct 24 08:00:01 2012	(r241988)
@@ -1054,13 +1054,20 @@ uaudio_chan_fill_info_sub(struct uaudio_
 			sed.v1 = NULL;
 		}
 
-		if ((acdp == NULL) &&
-		    (desc->bDescriptorType == UDESC_CS_INTERFACE) &&
-		    (desc->bDescriptorSubtype == AS_GENERAL) &&
-		    (desc->bDescriptorSubtype == UDESCSUB_AC_HEADER) &&
-		    (desc->bLength >= sizeof(*acdp))) {
-			acdp = (void *)desc;
-			audio_rev = UGETW(acdp->bcdADC);
+		if (audio_if == 0) {
+			if ((acdp == NULL) &&
+			    (desc->bDescriptorType == UDESC_CS_INTERFACE) &&
+			    (desc->bDescriptorSubtype == UDESCSUB_AC_HEADER) &&
+			    (desc->bLength >= sizeof(*acdp))) {
+				acdp = (void *)desc;
+				audio_rev = UGETW(acdp->bcdADC);
+			}
+
+			/*
+			 * Don't collect any USB audio descriptors if
+			 * this is not an USB audio stream interface.
+			 */
+			continue;
 		}
 
 		if ((acdp != NULL) &&
@@ -1132,9 +1139,8 @@ uaudio_chan_fill_info_sub(struct uaudio_
 					sed.v1 = (void *)desc;
 			}
 		}
-		if (audio_if == 0 || asid.v1 == NULL ||
-		    asf1d.v1 == NULL || ed1 == NULL ||
-		    sed.v1 == NULL) {
+		if (asid.v1 == NULL || asf1d.v1 == NULL ||
+		    ed1 == NULL || sed.v1 == NULL) {
 			/* need more descriptors */
 			continue;
 		}
@@ -1349,7 +1355,7 @@ uaudio_chan_fill_info(struct uaudio_soft
 			 * disable surround setups on FULL-speed USB
 			 * by default
 			 */
-			channels = 2;
+			channels = 4;
 			break;
 		default:
 			channels = 16;