Merge remote-tracking branch 'lsk/v3.10/topic/gator' into linux-linaro-lsk

[firefly-linux-kernel-4.4.55.git] / sound / usb / endpoint.c

diff --git a/sound/usb/endpoint.c b/sound/usb/endpoint.c
index 659950e5b94f6b411577a84821f1a1c4d93b4593..308c02b2a59746d0dfa9afceca53b1b85990f92a 100644 (file)
--- a/sound/usb/endpoint.c
+++ b/sound/usb/endpoint.c
@@ -467,6 +467,10 @@ struct snd_usb_endpoint *snd_usb_add_endpoint(struct snd_usb_audio *chip,
                        ep->syncinterval = 3;
 
                ep->syncmaxsize = le16_to_cpu(get_endpoint(alts, 1)->wMaxPacketSize);
+
+               if (chip->usb_id == USB_ID(0x0644, 0x8038) /* TEAC UD-H01 */ &&
+                   ep->syncmaxsize == 4)
+                       ep->udh01_fb_quirk = 1;
        }
 
        list_add_tail(&ep->list, &chip->ep_list);
@@ -1075,7 +1079,16 @@ void snd_usb_handle_sync_urb(struct snd_usb_endpoint *ep,
        if (f == 0)
                return;
 
-       if (unlikely(ep->freqshift == INT_MIN)) {
+       if (unlikely(sender->udh01_fb_quirk)) {
+               /*
+                * The TEAC UD-H01 firmware sometimes changes the feedback value
+                * by +/- 0x1.0000.
+                */
+               if (f < ep->freqn - 0x8000)
+                       f += 0x10000;
+               else if (f > ep->freqn + 0x8000)
+                       f -= 0x10000;
+       } else if (unlikely(ep->freqshift == INT_MIN)) {
                /*
                 * The first time we see a feedback value, determine its format
                 * by shifting it left or right until it matches the nominal