From: Alexander Tsoy Date: Tue, 21 Apr 2020 19:09:08 +0000 (+0300) Subject: ALSA: usb-audio: Apply async workaround for Scarlett 2i4 2nd gen X-Git-Tag: v5.7-rc3~28^2~5 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=cf9fb7b8737694818e783fc61e8fe220b7eaaf60;p=thirdparty%2Fkernel%2Flinux.git ALSA: usb-audio: Apply async workaround for Scarlett 2i4 2nd gen Due to rounding error driver sometimes incorrectly calculate next packet size, which results in audible clicks on devices with synchronous playback endpoints. For example on a high speed bus and a sample rate 44.1 kHz it loses one sample every ~40.9 seconds. Fortunately playback interface on Scarlett 2i4 2nd gen has a working explicit feedback endpoint, so we can switch playback data endpoint to asynchronous mode as a workaround. Signed-off-by: Alexander Tsoy Link: https://lore.kernel.org/r/20200421190908.462860-1-alexander@tsoy.me Signed-off-by: Takashi Iwai --- diff --git a/sound/usb/quirks.c b/sound/usb/quirks.c index 6c2dfd3bfcbf5..351ba214a9d3f 100644 --- a/sound/usb/quirks.c +++ b/sound/usb/quirks.c @@ -1806,6 +1806,7 @@ void snd_usb_audioformat_attributes_quirk(struct snd_usb_audio *chip, */ fp->attributes &= ~UAC_EP_CS_ATTR_FILL_MAX; break; + case USB_ID(0x1235, 0x8200): /* Focusrite Scarlett 2i4 2nd gen */ case USB_ID(0x1235, 0x8202): /* Focusrite Scarlett 2i2 2nd gen */ case USB_ID(0x1235, 0x8205): /* Focusrite Scarlett Solo 2nd gen */ /*