From 0d58273be0b9c3cec3be5488ca37f6ddbaf13cf0 Mon Sep 17 00:00:00 2001 From: "Geoffrey D. Bennett" Date: Sat, 21 Feb 2026 02:36:56 +1030 Subject: [PATCH] ALSA: usb-audio: Skip clock selector for Focusrite devices Add QUIRK_FLAG_SKIP_CLOCK_SELECTOR for Focusrite devices. During interface parsing, snd_usb_clock_find_source() reads the clock selector value then writes it back unchanged. On Focusrite devices this redundant write results in a ~300ms delay per altsetting, adding ~1.8s to probe time on a typical device with 6 altsettings. Enabling SKIP_CLOCK_SELECTOR skips the redundant write-back. Signed-off-by: Geoffrey D. Bennett Signed-off-by: Takashi Iwai Link: https://patch.msgid.link/00e53ae0a508b41516b41833daa17823381a649c.1771594828.git.g@b4.vu --- sound/usb/quirks.c | 1 + 1 file changed, 1 insertion(+) diff --git a/sound/usb/quirks.c b/sound/usb/quirks.c index b13d0f4d25ac..fbceed8e8d36 100644 --- a/sound/usb/quirks.c +++ b/sound/usb/quirks.c @@ -2424,6 +2424,7 @@ static const struct usb_audio_quirk_flags_table quirk_flags_table[] = { VENDOR_FLG(0x07fd, /* MOTU */ QUIRK_FLAG_VALIDATE_RATES), VENDOR_FLG(0x1235, /* Focusrite Novation */ + QUIRK_FLAG_SKIP_CLOCK_SELECTOR | QUIRK_FLAG_SKIP_IFACE_SETUP), VENDOR_FLG(0x1511, /* AURALiC */ QUIRK_FLAG_DSD_RAW),