Merge tag 'omap-for-v3.8-rc4/fixes-signed' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap into fixes

From Tony Lindgren:
Minimal omap fixes for the -rc series:

- A build fix for recently merged omap DRM changes

- Regression fixes from the common clock framework conversion
  for omap4 audio and omap2 reboot

- Regression fix for pandaboard WLAN control UART muxing caused by
  u-boot only muxing essential pins nowadays

- Timer iteration fix for CONFIG_OF_DYNAMIC

- A section mismatch fix for ocp2scp init

* tag 'omap-for-v3.8-rc4/fixes-signed' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap: (306 commits)
  ARM: OMAP2+: omap4-panda: add UART2 muxing for WiLink shared transport
  ARM: OMAP2+: DT node Timer iteration fix
  ARM: OMAP2+: Fix section warning for omap_init_ocp2scp()
  ARM: OMAP2+: fix build break for omapdrm
  ARM: OMAP2: Fix missing omap2xxx_clkt_vps_late_init function calls
  ARM: OMAP4: hwmod_data: Correct IDLEMODE for McPDM
  ARM: OMAP4: clock data: Lock ABE DPLL on all revisions
  + Linux 3.8-rc4

Signed-off-by: Olof Johansson <olof@lixom.net>

1 files changed, 16 insertions, 3 deletions

diff --git a/sound/usb/quirks.c b/sound/usb/quirks.c
index acc12f004c23..2c971858d6b7 100644
--- a/sound/usb/quirks.c
+++ b/sound/usb/quirks.c
@@ -387,11 +387,13 @@ static int snd_usb_fasttrackpro_boot_quirk(struct usb_device *dev)
 		 * rules
 		 */
 		err = usb_driver_set_configuration(dev, 2);
-		if (err < 0) {
+		if (err < 0)
 			snd_printdd("error usb_driver_set_configuration: %d\n",
 				    err);
-			return -ENODEV;
-		}
+		/* Always return an error, so that we stop creating a device
+		   that will just be destroyed and recreated with a new
+		   configuration */
+		return -ENODEV;
 	} else
 		snd_printk(KERN_INFO "usb-audio: Fast Track Pro config OK\n");
 
@@ -859,6 +861,17 @@ void snd_usb_endpoint_start_quirk(struct snd_usb_endpoint *ep)
 	if ((le16_to_cpu(ep->chip->dev->descriptor.idVendor) == 0x23ba) &&
 	    ep->type == SND_USB_ENDPOINT_TYPE_SYNC)
 		ep->skip_packets = 4;
+
+	/*
+	 * M-Audio Fast Track C400 - when packets are not skipped, real world
+	 * latency varies by approx. +/- 50 frames (at 96KHz) each time the
+	 * stream is (re)started. When skipping packets 16 at endpoint start
+	 * up, the real world latency is stable within +/- 1 frame (also
+	 * across power cycles).
+	 */
+	if (ep->chip->usb_id == USB_ID(0x0763, 0x2030) &&
+	    ep->type == SND_USB_ENDPOINT_TYPE_DATA)
+		ep->skip_packets = 16;
 }
 
 void snd_usb_ctl_msg_quirk(struct usb_device *dev, unsigned int pipe,