[alsa-devel] [PATCH] ALSA: usb-audio: add implicit fb quirk for MOTU M Series

[Alexander Tsoy]

This fixes crackling sound during playback.

Signed-off-by: Alexander Tsoy <alexander at tsoy.me>
---

MOTU is known for reusing Product IDs for different devices or different
generations of the device (e.g. MicroBook I/II/IIc shares a single Product
ID). This patch was only tested with M4 audio interface, but the same
Product ID is also used by M2. Hope it will work for M2 as well.

 sound/usb/pcm.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/sound/usb/pcm.c b/sound/usb/pcm.c
index a11c8150af58..4f1c00615d94 100644
--- a/sound/usb/pcm.c
+++ b/sound/usb/pcm.c
@@ -348,6 +348,10 @@ static int set_sync_ep_implicit_fb_quirk(struct snd_usb_substream *subs,
 		ep = 0x84;
 		ifnum = 0;
 		goto add_sync_ep_from_ifnum;
+	case USB_ID(0x07fd, 0x0008): /* MOTU M Series */
+		ep = 0x81;
+		ifnum = 2;
+		goto add_sync_ep_from_ifnum;
 	case USB_ID(0x0582, 0x01d8): /* BOSS Katana */
 		/* BOSS Katana amplifiers do not need quirks */
 		return 0;
-- 
2.24.1