This is a note to let you know that I've just added the patch titled ALSA: usb-audio: Optimize TEAC clock quirk to the 5.18-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: alsa-usb-audio-optimize-teac-clock-quirk.patch and it can be found in the queue-5.18 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 3753fcc22974affa26160ce1c46a6ebaaaa86758 Mon Sep 17 00:00:00 2001 From: Takashi Iwai <tiwai@xxxxxxx> Date: Tue, 31 May 2022 15:07:49 +0200 Subject: ALSA: usb-audio: Optimize TEAC clock quirk From: Takashi Iwai <tiwai@xxxxxxx> commit 3753fcc22974affa26160ce1c46a6ebaaaa86758 upstream. Maris found out that the quirk for TEAC devices to work around the clock setup is needed to apply only when the base clock is changed, e.g. from 48000-based clocks (48000, 96000, 192000, 384000) to 44100-based clocks (44100, 88200, 176400, 352800), or vice versa, while switching to another clock with the same base clock doesn't need the (forcible) interface setup. This patch implements the optimization for the TEAC clock quirk to avoid the unnecessary interface re-setup. Fixes: 5ce0b06ae5e6 ("ALSA: usb-audio: Workaround for clock setup on TEAC devices") Reported-by: Maris Abele <maris7abele@xxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20220531130749.30357-1-tiwai@xxxxxxx Signed-off-by: Takashi Iwai <tiwai@xxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- sound/usb/clock.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) --- a/sound/usb/clock.c +++ b/sound/usb/clock.c @@ -573,10 +573,14 @@ static int set_sample_rate_v2v3(struct s } /* FIXME - TEAC devices require the immediate interface setup */ - if (rate != prev_rate && USB_ID_VENDOR(chip->usb_id) == 0x0644) { - usb_set_interface(chip->dev, fmt->iface, fmt->altsetting); - if (chip->quirk_flags & QUIRK_FLAG_IFACE_DELAY) - msleep(50); + if (USB_ID_VENDOR(chip->usb_id) == 0x0644) { + bool cur_base_48k = (rate % 48000 == 0); + bool prev_base_48k = (prev_rate % 48000 == 0); + if (cur_base_48k != prev_base_48k) { + usb_set_interface(chip->dev, fmt->iface, fmt->altsetting); + if (chip->quirk_flags & QUIRK_FLAG_IFACE_DELAY) + msleep(50); + } } validation: Patches currently in stable-queue which might be from tiwai@xxxxxxx are queue-5.18/alsa-usb-audio-add-missing-ep_idx-in-fixed-ep-quirks.patch queue-5.18/alsa-usb-audio-workaround-for-clock-setup-on-teac-devices.patch queue-5.18/alsa-usb-audio-optimize-teac-clock-quirk.patch queue-5.18/alsa-usb-audio-configure-sync-endpoints-before-data.patch